Glossary of Terms for Thoracic Radiology: Recommendations of the

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Glossary of Terms for Thoracic Radiology:
Recommendations
of the Nomenclature
Committee
Fleischner Society1
The Fleischner
Society was founded in 1969 by a group of
radiologists
to honor the memory
of Felix Fleischner
and to
promote the exchange
of information
between
basic scientists
and clinical investigators
interested
in chest disease.
Today
this multidisciplinary
group is best known for the Symposia
on Chest Disease that it conducts
annually, but it has sought,
in the words
of its motto,
“to advance
knowledge
of the
normal and diseased
chest” in various other ways. The Glossary presented
here represents
one such effort.
The Glossary
was originally
proposed
at the first general
meeting of the Society of 1 971 in the belief that standardization
of terms
with
respect
to the
description
of radiographic
findings would facilitate
the exchange
of information.
Various
members
of the Society have contributed
to its development
over the intervening
years, and though such an undertaking
is never truly completed,
the Glossary
is now judged
to be
sufficiently
inclusive
to be of general
interest.
The Society,
therefore,
authorized
its publication
as a report of the Nomenclature Committee
in May 1983.
The development
of a glossary
is a process that casts light
on both the meaning
of words and on the basics of human
behavior.
The use of words, it appears,
is a highly personal
attribute
of the individual,
and any disagreement
with that
usage is instinctively
viewed as a personal assault: A nomenclature
committee
does not need a chairman;
it needs a
“peace-keeping
force”! It is, therefore,
a great tribute to those
who participated
that they were ultimately
able to put personal
bias and national linguistic
differences
aside and to agree on
the definitions
presented
here.
The Committee,
comprising
more “splitters”
than “lumpers,”
has sought
to identify
nuances
of meaning
that distinguish
words of similar connotation
and has systematically
rejected
the argument
that “everyone
says it that way” as a justification
for the misuse of a word. It has also attempted
to indicate
whether
specific
terms are truly descriptors
or are, in fact,
diagnostic
conclusions;
and if the latter, whether
or not they
can appropriately
be based solely on radiographic
evidence.
It is hoped that publication
of this Glossary
will stimulate
interest
in the standardization
of descriptive
terminology
in
chest radiology,
that some will adhere to the definitions
pre-
1
Address reprint requests to W. J. Tuddenham,
AJR
143:509-517,
September
Department
1984 0361-803X/84/1433-0509
of Radiology.
0 American
of the
sented here, and that those who do not will, at least, become
more thoughtful
in their choice of words.
Thanks
are due to those members
of the Society
who
launched
this effort: Gordon
Cumming
(Midhurst,
England)
and E. Robert Heitzman
(Syracuse,
NY); to those who sustamed it: John J. Fennessy
(Chicago,
IL), Paul J. Friedman
(San Diego, CA), Ronald Grainger(Sheffield,
England), William
H. Northway,
Jr. (Palo Alto, CA), and the late George Jacobson (Los Angeles,
CA); and most particularly
to those on
whom fell the burden
of bringing
it to fruition:
John H. M.
Austin (New York, NY), Robert G. Fraser (Birmingham,
AL),
David H. Trapnell (London,
England) and Morris Simon (Boston, MA).
William
J. Tuddenham
Chairman,
Editor’s
Nomenclature
Committee
The Fleischner
Society
Note
At its recent meeting
in Santa Fe, the Fleischner
Society
reaffirmed
its hope this Glossary
will prove helpful in refining
the radiographic
vocabulary
for describing
and thinking about
thoracic
disease.
The Society also realizes these definitions
and comments
on their usage (evaluations)
may not satisfy
all readers.
A certain
dogmatism
has been required
to reach
final statements
about terms that may be used differently
by
others. To achieve a wider consensus
on the acceptance
of
controversial
terms, the Society invites comments,
criticisms,
and suggested
additions.
These may be directed
to the AJR
Editorial
Office
or to Dr. Robert
Fraser
(Department
of
Radiology,
University
of Alabama
Medical Center, 619 5. 19th
St., Birmingham,
AL 35233). Dr. Fraser is the new chairman
of the
Nomenclature
Committee;
the
committee
will
synthesize
constructive
suggestions
into revisions
in the
Glossary.
Readers are urged to respond to this invitation
and
to help the Society reduce imprecision
in our vocabulary
so
the complexities
of thoracic disease may be better understood
and communicated.
MMF
Pennsylvania
Roentgen
Hospital, 8th and Spruce Sts., Philadelphia,
Ray Society
PA 19107.
510
FLEISCHNER
A
abscess,
but including
n, -es. 1. Pathol. An inflammatory mass
lung parenchyma,
the central part of which
within
has undergone
purulent
liquefaction
necrosis.
It
may communicate
with the bronchial tree. 2.
Radio!. A mass within lung parenchyma which, if
it communicates
with the bronchial tree, contains
a cavity. Otherwise,
a pulmonary
mass can be
considered
to represent an abscess in the morphologic
sense only by inference. -Qualifiers:
Expressing clinical course: acute, chronic. Expressing etiology: bacterial, fungal, etc. Expressing site of involvement:
lung, mediastinal,
etc. Evaluation:
An inferred conclusion,
the use of
which as a radiobogic diagnosis is appropriate
only with reference
to masses
of presumed
infec-
tious origin; cf. cavity.
absorber,
n, -s. Radio!phys.
Any object that atten-
uates an x-ray beam.
pattern,
n, -a. Radio!. A collection of round,
poorly defined, discrete or partly confluent opacities in the lung, each 4-8 mm in diameter and
together producing an extended, inhomogeneous
shadow. -Synonyms:
rosette pattem,
acinonodose pattem (used specifically with reference to
acinar
endobronchial
spread of tuberculosis),
alveolar
pattem
(inaccurate
descriptor;
not
recommended).
-Evaluation:
An inferred
conclusion
usually used as a descriptor.
An acceptable
term.
acinar shadow,
n, -a. Radio!. A round or ovoid,
poorly
defined
pulmonary
opacity
4-8 mm in
diameter,
presumed
to represent
an anatomic
acinus renderedopaque
by consolidation. Usually
used only in the presence ofmany
such opacities;
cf. acinar pattern.
-Evaluation:
An inferred conclusion
applicable as a radiobogic de-
sometimes
scriptor.
acinus,
n, -I. Anat. The part of the lung distal to a
terminal
bronchiole.
It consists
of respiratory
bronchioles,
alveolar ducts, alveolar sacs, alveoli,
and their blood vessels, lymphatics, and supporting tissues.
aerate, v. 1. To fill with air. 2. To expose to air. 3.
To oxygenate.
aerated,
adj. 1. Inflated, filled wtih air (lungs). 2.
Air-containing
(paranasal
sinuses).
3. Exposed to
air (blood).
aeration,
n. Physiol/radiol.
1. The state of containing air. 2. The state or process of admitting or of
being filled or inflated with air. 3. The state or
process
of being exposed to air. -Qualifiers:
over- (preferred) or hyper- ; under- (preferred)
or
hypo-. -Synonyms:
inflation.
See also vanillaoxygenation.
-Evaluation:
Acceptable
term with reference
to inspiratory
phase of respiration. Inflation is preferred
in sense 2.
air, n. Radio!. Gas within the body, regardless of its
composition
or site. -Synonym:
gas. -Evaluation: The word air should be used to refer only to
inspired atmospheric
gas. With reference
to
hen,
pneumothoraces,
subcutaneous
emphysema
or
etc., gas is
the content
of the stomach,
colon,
the preferred
term.
air bronchogram,
n, -a. Radio!. The radiographic
shadow of an air-filled bronchus peripheral
to the
hilum and surrounded
by airless lung (whether by
virtue of absorption
of air, replacement of air or
both);
a finding
generally
regarded
as evidence
of the patency
of the more proximal airway;
hence, any bandlike
tapering and/or branching
lucency within opacafled lung corresponding
in
size and distribution
to a bronchus or bronchi
and presumed to represent
an air-filled segment
of the bronchial
tree. -Evaluation:
A specific
feature of radiobogic anatomy whose identity is
often
inferred. A useful and recommended
term.
level, n, -s. Radio!. See fluid level.
airspace,
n. Anat. The gas-containing
part of the
air-fluid
lung exclusive of the
purely
conducting
airways,
SOCIETY
the respiratory
GLOSSARY
bronchioles.
monic window.
-adj. Pathol/Physiol/Radiol.
Of or pertaining to
any process believed to be confined to the anatomic airspace or to a part thereof(e.g., airspace
consolidation).
-Synonyms:
acinar, alveolar. Evaluation:
Inferred
conclusion
appropriately
based
on radiologic
evidence
and an acceptable
descriptor.
air trapping, n. 1. Pathophysiol.
The retention
of
excess air in all or part of the lung as a result of
airway closure during the expiratory maneuver;
classically implies an increasing amount of retamed air at equivalent
expiratory
positions
in
successive
expiratory maneuvers. 2. Radio!. The
retention of excess air in all or in some part of
the lung at any stage of expiration. -Evaluation:
2. A specific radiologic statement to be used only
if excess air retention is demonstrated
by a dynamic study (e.g. , inspiration-expiration
radiography or fluoroscopy). Not to be used with reference to ovennflation
of the lung at full inspiration
(total lung capacity).
airway, n. Anat. 1. A collective
term for the airconducting
passages from the larynx to and induding the terminal bronchioles. 2. Any air-conducting tube or passage.
-adj. Pathol/Physiol/Radiol.
Of or pertaining
to
the anatomic airway
or a part thereof (e.g.. dostructive
airway disease). -Evaluation:
Inferred
conclusion
appropriately
based on radiobogic cvidance. An acceptable
descriptor.
alveolarizatlon,
n. Radio!. The opacification
of clusters of minute airways (presumed to be alveoli)
by a contrast
agent. -Evaluation:
Excessive
fill-
ing of peripheral airways by a contrast agent
usually used for bronchography may opacity respiratory bronchioles,
but seldom alveoli. Thus,
the correct term is bronchiolar
filling orbronchiolar opacification.
alveolar pore, n, -s. Anat/Physiol.
A microscopic
communication between
alveoli. Together with
the canals of Lambert
and direct airway anastomoses, the alveolar pores provide for the collateral passage of gas or liquid from one pulmonary
unit to another;
of. collateral
ventilation.
-Synonym: pore of Kohn.
anterior
junction
line, n. Radio!. A vertically
oriented linear or curvilinear opacity about 1 mm
wide and commonly
projected
on the tracheal air
shadow. It is produced by the shadows of the
right and left pleurae in intimate contact between
the aerated
lungs anterior
to the great vessels
and sometimes
the heart; hence, it never extends
above the suprastemal
notch. -Synonyms:
anterior mediastinal
septum, anterior mediastinal
line. -Evaluation:
A specific feature of radiologic
anatomy;
preferred
to cited synonyms.
sortie knob, n. RadiO!. That part of the aortic arch
that is seen end-on in a frontal radiograph.
In the
normal, it is characterized by a sharply defined,
arcuate superolateral border and lies to the left
of the trachea above the main pulmonary artery.
-Synonyms:
aortic
knuckle.
-Evaluation:
A
specific
feature
of radiobogic anatomy. An ac-
ceptable term.
window,
n. 1. Anat. A mediastirtal
space bounded anteriorly by the ascending aorta;
posteriorly
by the descending aorta; superiorly
by the aortic arch; inferiorly by the left pulmonary
artery; medially by the left side of the trachea,
left main bronchus, and esophagus; and laterally
by the left lung. Within it are situated the ductus
ligament. the left recurrent laryngeal nerve, lymph
nodes, and fat. 2. Radio!. A zone of relative
lucency in the mediastinal
shadow, which is best
seen in the left anterior oblique projection and
which correspondstothe
anatomic space defined
above. On a frontal chest radiograph,
the lateral
aortopulmonary
margin
of this
monary window
space constitutes
the
interface.
-Synonym:
AJR:143,
aortopulaortopul-
of radiologic
arterlovenous
September
1984
-Evaluation:
2. A specific feature
anatomy.
An acceptable
term.
flstUla,
n, -ae. 1. Pathol anat. A
direct communication
between an artery and a
vein that bypasses the capillary bed. 2. Radio!. A
shadow complex, comprising
a nodular pulmonary opacity
associated
with dilated
vascular
shadows,
that is presumed to represent an arteriovenous
fistula in the anatomic
sense. (Such
lesions are often multiple.) -Synonyms:
arteriovenous aneurysm, arteriovenous
malformation.
Arteriovenous fistula or aneurysm
refers to a
lesion of congenital
or traumatic
origin; arteriovenous
malformation
should be reserved for le-
sions ofcongenital
origin. -Qualifiers:
traumatic,
congenital.
-Evaluation:
In conventional
radiographs, an inferred conclusion
sometimes justifled by the radiographic evidence alone. In pubmonary
arteriography,
an explicit
radiographic
diagnosis.
atelectasis,
n. 1. Pathol phys. Less than normal
kiflation ofall or part ofthe lung with corresponding diminution
in lung volume. 2. Radio!. Radiologic evidence of diminished
volume affecting
all
or part of a lung, which may or may not include
bss ofnormal
lucency in the affected part of lung.
(This finding is not to be confused with diminished
volume produced by resection of pulmonary
tissue.) -Qualifiers:
Expressing
mechanism:
resorption
(obstructive),
secondary
to airway obstruction; relaxation
(passive, compression),
secondary to the effect of an adjacent space-occupying process; surfactant
deficit; cicatrization
(scar), secondary
to fibrotic contraction. Expressing distribution:
total pulmonary,
bobar, segmental, subsegmental,
platelike,
discoid,
platter, bin-
ear. Expressing severity: minor (mild), moderate,
marked (severe), total (complete). -Synonyms:
anectasis,
loss of volume, collapse. Anectasis is
usually used in reference to failure of lung expan.
sion
ume
and
can
in the newborn;
atelectasis
and loss of vol-
refer to acquired diminution in lung volume
do not connote severity. Collapse, in Ameri-
usage, refers to total atelectasis;
in British
collapse has the more general meaning of
atelectasis
(2, above). -Evaluation:
A conclusion
conceming
pathophysiobogy
that is appropriately
based on radiographic
evidence alone.
attenuate,
v. Radio!phys.
To reduce the energy of
an x-ray beam.
attenuation, n. Radio! phys. A collective term for
the processes
(absorption
and scattering) by
which the energy of an x-ray beam is diminished
In its passage
through matter.
azygoesophageal
recess,
n. 1. Anat. A space or
recess in the right side of the mediastinum
into
which the medial edge of the right bower lobe
(crista pulmonis) extends.
It is limited superiorly
by the arch of the azygos vein, posteriorly by the
azygos vein in front of the vertebral column, and
usage,
medially by the esophagus and its adjacent structures. (The exact relation
between the medial
edge of the lung and the mediastinal structures
varies.) 2. Radio!. In a frontal chest radiograph,
a
vertically
oriented
interface between
air in the
right lower lung and the adjacent mediastinum
that represents
the medial limit of the anatomic
azygoesophageal
recess. -Evaluation:
2. A spacific feature of radiologic
anatomy.
The use of the
term recess to identify a linear shadow is mappropriate;
medial boundary or limit or azygoesophageal recess is preferred.
azygos vein, n. Radio!. A slight, ovoid prominence
of the mediastinal
shadow
commonly
seen in
frontal
chest radiographs
in the angle formed by
the right main bronchus and the trachea. The
shadow is produced principally
by the azygos
veln projected end-on, but azygos lymph nodes
may contribute to it. -Evaluation:
A feature of
radiobogic anatomy of some descriptive value rel-
MR:143,
FLEISCHNER
September1984
ative to the status of the systemic venous volume
and pressure
and azygos vain flow volume;
an
term.
B
cated, thin-walled lucency contiguous with the
pleura, usually at the lung apex. -Synonyms:
type I bubla(Reid), bulla, air cyst. -Evaluation:
2.
conclusion,
seldom
justified
by the
radiograph alone. Bulla or air cyst is preferred.
belle, n, -as. 1. Patho! anat. a. A sharply demarcated region of emphysema 1 cm or more in
diameter. b. An abnormal space within the lung
1 cm or more in diameter that may contain only
gas (type II of Reid), or may contain, in addition,
blood
vessels
and ruptured
alveolar
walls
(type
Ill of Reid). Aform ofpulmonary
aircyst. 2. Radio!.
lucency 1 cm or more in
Any sharply demarcated
diameter within the lung, the wall of which is less
than 1 mm thick. -Qualifiers:
small, medium,
large. -Synonyms:
blab, air cyst; pneumatocele
is not a proper synonym. -Evaluation:
2. An
inferred conclusion.
usually justified by the radiographic findings. An acceptable
term.
butterfly
distribution,
n. Radio!. See batwing
disthbutlon.
(To be distinguished
from the use of
this term in general
medicine
to describe
the
distribution
of certain cutaneous
lesions.)
C
calcific,
adj. 1. Of or pertaining to deposits of
insoluble
calcium
salts. 2. Radio! [said of a
shadow). a. Significantly
moreopaquethan
shad-
ows of soft tissues of comparable
therefore,
thickness and,
presumed
to represent
a calcified
tissue. b. Similar in opacity to shadows of structures
of comparable thickness that are known to be
calcified.
calcification,
n, -S. 1. The state or process of being
rendered calcareous by the deposition of calcium
salts. 2. A calcified structure.
Specifically:
pulmonary calcification,
n. 1. Pathophysiol. a. The
process
by which one or more deposits
of calcsum salts are formed within lung tissue or within
a pulmonary lesion. b. Such a deposit of calcium
salts. 2. Radio!. A calcific opacity within the lung
that may be organized in the sense of concentric
lamination,
for example,
but which does not display the trabecular
organization
of true bone. Qualifiers:
eggshell,
popcorn,
etc. (q.v.) -Evaluation: An explicit statement; may be used as a
descriptor. A useful term. To be distinguished
from pulmonary
ossification
(q.v.).
calcified,
adj. 1. Having undergone
calcification;
containing
calcium
safts. 2. Radio!.
Containing
calcific shadows.
calcify,
v. To make or to become stony or calcareous by the deposition or secretion of calcium
salts.
cardiac
rncisura,
n. Radio!. The concavity
in the
511
GLOSSARY
left heart border seen in the frontal (or right
anterior oblique) chest radiograph just below the
left hilum and representing
the junction between
the main pulmonary
artery and the left ventricular
myocardium.
The tip of the left atilal appendage
may underlie the rncisura. -Evaluation:
A feature
of radiobogic anatomy. An acceptable
band shadow,
n, -s. Radio!. See linear opacity.
batwlng
distribution,
n. RadiO!. A spatial arrangement of radiographic
opacities
in a frontal radiograph that bears a vague resemblance
to the
shape of a bat in flight; said of coalescent, poorly
defined opacities
that are nearly bilaterally symmetric and that are confined to the central oneto two-thirds of the lungs. (Lesions that produce
such shadows
are not necessarily peripheral
or
central in location.) -Synonym:
butterfly distribution. -Evaluation:
A radiologic
descriptor
of
limited usefulness.
blab, n, -a. 1. Patho! anat. A gas-containing
space
within the visceral pleura of the lung. A form of
pulmonary
air cyst. 2. RadiO!. A sharply demar-
An inferred
SOCIETY
term.
sa#{241}nslangle,
n. Anal/Radio!. The angle formed
between the right and left main bronchi in a frontal
chest radiograph. -Synonyms:
bifurcation
angb, angle of tracheal bifurcation. -Evaluation:
A
definitive anatomic
and radiologic
measurement.
cavIty, n, -lea. 1. PatPiol ens!. A gas-filled space
within a zone ofpulmonary
consolidation
or within
a mass or nodule, produced by the expulsion of
a necrotic part of the lesion via the brOnchial tree.
2. RadiO!. A lucency within a zone of pulmonary
consolidation,
a mass. or a nodule;
hence,
a
lucent area within the lung that may or may not
contain a fluid level and that is surrounded
by a
wall, usually of varied thickness.
-Evaluation:
2.
An inferred conclusion often used as a descriptor.
The term expresses
pathologic
anatomy without
causative
connotation.
It is a useful radiobogic
descriptor; it is not synonymous with abscess,
which may exist without cavitation.
circumscribed,
adj. Radio!.
Possessing
a cornpletely or nearly completely
visible border.
Evaluation:
An acceptable descriptor: cf. defined.
coalescent,
adj. Radio!. Joined together;
said of
multiple opacities joined to form a single opacity,
but stlH individually
identifiable;
cf. confluent,
composite.
-Evaluation:
An acceptable descrip-
with or without evidence of enlargeheart chambers
occurring
in
association
with evidence
of chronic lung disease. -Qualifiers:
acute, chronic. -Evaluation:
2. An inferred radiologic conclusion that depends
on radiographic
signs that are usually,
but not
invariably,
reliable; an acceptable
descriptor.
Dcspite pathology
def. 1, radiologic
evidence
of
cardiornegaly
need not be present.
cyst, n, -S. 1. Patho! anat. A circumscribed
space,
1 cm ormore in diameter, containing gas or liquid,
whose wall is generally
thin, weN defined.
and
composed
of a variety of ceflular elements.
2.
Radio!. A circumscribed lucency or opacity within
the lung or mediastinurn,
1 cm or more in diameter, that is presumed to represent a cyst in the
pathologic
sense. -Qualifiers:
1. foregut (bronchogenic.
esophageal
duplication);
postinfection.
2. air. -Evaluation:
2. This term is appropriate
for the description
of any thin-walled,
gas-contaming
pulmonary
space
of uncertain cause
whose wall is more than 1 mm thick. The term is
entirely nonspecific
and, if possible,
a more spacific term(bleb,
bul!a,pneumatocele)
is preferred.
hypertension
mont
of the right
D
condemned.
The term coin may be descriptive
of
the shadow,
but certainly not of the lesion producing it.
composite,
adj. Radio!. Comprising
more than one
element;
said of a shadow
complex made up of
multiple
contiguous
or superimposed
elements
that may or may not be separately
identifiable.
consolidate,
V. 1. To become
firm or hard (as by
solidifying).
2. To cause to become firm or hard.
consolidated,
adj. Having
become
firm or solid;
having undergone
consolidation.
consolidation,
n, -S. 1. Pathophysiol.
a. The proness by which air in the lung is replaced by the
products
of disease rendering the lung solid (as
in pneumonia). b. The state of pulmonary
tissue
so Solidified. 2. Radio!. An essentially homogefocus opacity
in the lung characterized
by little
or no loss of volume, effacement
of blood vessel
shadows,
and sometimes
by the presence
of an
air bronchogram
(q.v.). Applicable only in an
appropriate
clinical setting when the opacity can
with reasonablecertainty
beattributed
to replacement of alveolar air by exudate, transudate, or
tissue. -Evaluation:
2. An inferred conclusion.
A
useful term when used in strict accord with the
definitiOn above. Not to be used with reference
to any homogeneous
opacity.
contrast medium, n, -Ia. RadiO!. An agent administered to render the lumen of a hollow structure,
vessel. or viscus more or less opaque than its
surroundforthe
purposeof radiographic
imaging.
-Synonyms:
contrast agent, opaque medium,
opaque. -Evaluation:
The use of contrast or dye
adj. Radio!. Possessing
density
(q.v.). Usually used in describing
or comparing
radiographs
or radiographic
shadows
with respect
to their
light transmission.
-Synonyms:
black, heavily
exposed.
-Evaluation:
A recommended term ,ri
the context
defined. Should not be used in referring to the opacity of an absorber to x-radiation.
See opaque,
opacity.
density,
n, -Isa. 1. Photom/Radiol.
a. The property
of an exposedand
processed
photographic
emulsion thatdetermines
itslight absorptlon/transmissiori characteristics;
hence: b. The opacity
of a
radiographic
shadow
to visible bight; film blackening. 2. RadiO!. A qualitative
expression of the
degree of film blackening usually expressed
in
terms of the blackening
of one film or shadow
relative
to another. 3. Photom. A quantitative
expression
of the degree of film blackening
defined as: density
=
bogio X intensity
(incident
light)[intensity (transmitted
light); optical density.
4. RadiO!. The shadow
of an absorber
more
opaque to x-rays than its surround; an opacity or
radiopacity:
5. The degree of opacity
of an absorber to x-rays, usually expressed
in terms of
the nature of the absorber
(e.g., bone density).
6. Phys. The mass of a substance per unit volume. -Synonyms:
1. light absorption.
film blackening. 4. opacity.
radiopacity.
-Qualifiers:
2.
increased,
decreased.
3. increased, decreased,
maximum. 5. air, water, metal, soft tissue, bone,
fat; increased,
decreased,
etc. -Evaluation:
In
dots. 1-3, the term refers to a fundamental
characteristic
of the radiograph. This use is recornmended.
In dots. 4 and 5, the term refers to the
character
of an absorber and has an exactly
opposite
connotation
with respect to film blackening. Because
of this potential
confusion,
the
term should never be used to mean an opacity
(radiopacity).
diffuse,
adj.
1. Widespread.
2. Pathophysioi.
Widely distributed
through an organ or type of
tissue.
3. Radio!. Widespread
and continuous
Lsaid of shadows and, by inference, of the states
or processes producing them). -Synonyms:
dis-
to refer to a contrast medium is to be condemned,
as is the use of the plural form, contrast
media,
to refer to a single contrast agent.
cor pulmonale,
n. 1. Patho! anat/Clin.
Right ventricular hypertrophy
and/or dilatation occurring as a
result of an abnormality
of lung structure or function. 2. Radio!. Evidence of pulmonary arterial
the context
of chest radiology,
diffuse connotes
widespread,
anatomically
continuous, but not
necessarily
complete
involvement
of the lung or
other thoracic
structure or tissue; disseminated
connotes
widespread
but anatomically
discontinuous involvement;
generalized
connotes
corn-
tor.
coin lesion, n. Radio!. A sharply defined, circular
opacity
within the lung. suggestive
of the appearance
of a coin and usually representing
a
spherical
or nodular
lesion. -Synonyms:
pulmonary nodule, pulmonary
mass. -Evaluation:
A radiologic descriptor,
the use of which is to be
dense,
seminated, generalized,
systemic, widespread.
In
FLEISCHNER
512
plete or nearly complete
involvement,
whereas
systemic
connotes
involvement
of a thoracic
structure
or tissue as part of a process involving
the entire body. -Evaluation:
3. A useful and
acceptable
term.
-v.
To spread, to extend in continuity in all
directions.
dirty chest, n. Radio!. An appearance of the lungs
characterized
by acompbex ofabnormal
shadows
of wide distribution and varying form and character. -Synonym:
dirty lung. -Evaluation:
A
colloquial
descriptor
so indefinite
as to defy
ac-
curate definition. To be rejected in favor of more
precise descriptors.
disseminate,
v. To spread, as seed.
dissemInated,
adj. 1. Widespread; sown as seed.
2. Pathophysiol.
Widely but discontinuously
distributed
through an organ or type of tissue. 3.
Radio!. Widespread
but anatomically discontinuous
[said of shadows
and, by inference,
of the
states or processes producing them]. -Eva!uation: 3. A useful and acceptable term.
doubling
time, n, -a. Radio!. The time in which a
pulmonary nodule or mass doubles in volume
(increases
in diameter
by a factor of 1 .25): a
semiquantitative expression of the growth rate of
a lesion. -Evaluation:
An acceptable term. The
concept of growth rate is of very limited value as
a criterion for distinguishing benign from malignant nodules.
E
eggshell
calcification,
n. Radio!. Thin, sharply dofined, curvilinear,
calcific opacities
occurring
in
the periphery
of a lesion or anatomic structure
such as a lymph node. -Synonym:
curvilinear
calcification.
-Evaluation:
An acceptable radiologic descriptor.
embolism,
n. 1. Pathol. The complete
or partial
destruction ofthe lumen ofa blood vessel, usually
an artery, by the sudden impaction
of foreign
material carried in the blood stream; cf. infarclion. 2. Radio!. A complex of radiographic and/or
scintigraphic
abnormalities presumed to represent embolism
in the pathologic
sense. -Evaluation: An inferred conclusion
that in some cases
can be based on radiographic
or scintigraphic
evidence alone.
embolizatlon,
n. Pathol. The pathologic
process by
which the lumen of a blood vessel is suddenly
obstructed
by blood clot or foreign material carried out in the bloodstream. -Qualifiers:
thera-
peutic, referring to the technique by which the
lumen of a blood vessel is deliberately
occluded
by the introduction
offoreign
objects or materials.
embolus,
n. -i. 1. Patho!. A blood clot or mass of
foreign
material that has been carried in the
bloodstream
and that partly or completely
ccciudes the lumen of a blood vessel; Cf. thrombus.
2. Radio!. A lucent defect or obstruction
within
an opacifled
vessel presumed
to represent
an
embolus
in the pathologic
Expressing
sense.
clinical course:
-Qualifiers:
acute, chronic.
Ex-
pressing nature of embolic material: air, fat, amniotic fluid, parasitic,
neoplastic.
tissue, foreign
materials (e.g., iodized oil, mercury,
talc). Miscellaneous:
septic, therapeutic,
paradoxic.
-Eva!uation: 2. A radiologic conclusion
that may appro-
priately
be based
on arteriographic
evidence
alone.
emphysema,
n. 1. Pathol anat. a. A morbid condition of the lung characterized by abnormally cxpanded air spaces distal to the terminal bronchicle with or without destruction
of the air-space
walls (per Ciba Conference, 1959). b. As above,
but “with destruction
of the walls of involved air
spaces
specified
tion,
1961 , and
(per World
American
Health OrganizaThoracic
Society
SOCIETY
GLOSSARY
[ATS], 1962). 2. Radio!. Hyperinflatlon
(q.v.) of
all or part of one or both lungs. with or without
associated
alteration
in pulmonary
vascular
pattem, presumed to represent morphologic
emphyserna; applicable
only in an appropriate clinical
sethng
and,
in the sense
not applicable to spasmodic
of
the
ATS
definition,
asthma or cornpen-
satory hyperinflation.
-Qualifiers:
Morpho!. contribobular, panlobular,
paraseptal,
focal-dust,
alveolar duct, paracicatricial,
etc.; Clin. local, genoral, bobar, segmental, senile, compensatory,
surgical; mild, moderate,
severe, etc. -Synonyms:
None; overinflation
and hyperaeration
are not
strictly
synonymous
with emphysema;
emphysematous
lungs are invariably overinflated, but
overmnflated
lungs are not invariably
emphysematous. -Evaluation:
2. An inferred conclusion
acceptable
only if used in strict accordance with
the definition
above.
exudate,
n, -S. 1. Pathophysiol. a. Highly protelna000us fluid that may or may not contain inflam-
matory cells, is derived from the blood, is elaborated as part of the inflammatory response
of the
lung. pleura, or other tissues, and is deposited in
extravascular
tissue spaces and on tissue surfaces. b. An accumulation ofsuch fluid. 2. Radio!.
A poorly defined opacity in the lung that neither
destroys
nor displaces its gross architecture; applicable only to an opacity that, on the basis of
clinical or other evidence, can be attributed with
reasonable
certainty
to a pulmonary
infection
or
other inflammatory process. -Evaluation:
2. An
inferred conclusion
usually used as a descriptor.
A useful and acceptable
term when used in accordance
with the definition
above. To be distinguished from transudate.
exudation,
n. The process by which exudate
(vs.)
is formed.
exudative,
adj. Of or pertaining
to an exudate.
F
fibrocalcific,
adj. Radio!. Of or pertaining
to sharply
defined, linear, and/or nodular opacities
containing cabclficalion(s)(q.v.),
usually occurring in the
upper lobes and presumed
to represent old granubornatous
lesions-Evaluation:
A widely used
and acceptable
radiobogic descriptor.
flbronodular,adj.
Radio!. Oforpertainingto
sharply
defined, approximately
circular opacities, occurring singly or in dusters,
usually in the upper
lobes of the lungs and associated with linear
opacities
and distortion
(retraction)
of adjacent
structures.
A finding usually presumed
to represent old granubomatous
disease, but no inference
concerning
the activity of such a lesion is justified
on the basis of a single radiograph-Evaluation:
An inferred conclusion
usually used as a radiologic descriptor. Its use is not recommended.
fibrosis,
n. 1. PotPie!. a. Cellular fibrous tissue or
dense
acellular
collagenous
tissue.
b. The
process of proliferation
of fibroblasts
leading to
the formation
of fibrous or collagenous
tissue. 2.
Radio!. Any opacity presumed to represent
fibrous or collagenous
tissue;
applicable
to linear,
nodular,
or stellate opacities that are sharply
defined, that are associated
with evidence of loss
of volume in the affected part of the lung and/or
with deformity
of adjacent structures, and that
show no change
over a period of months or
years. Also applicable
with caution to a diffuse
pattem of opacity if there is evidence of progressiveboss oflung volumeor
ifthe pattern of opacity
is unchanged
over time, with or without compensatory overmnflation.-Evaluation:
2. An inferred
conclusion
often used as a radiobogic descriptor.
An acceptable
term if used in strict accordance
with the criteria cited.
fIbrotic,
adj. 1. Pathol. Of or pertaining to fIbrosis
AJR:143,
September 1984
(vs.). 2. Radio!.
Of or pertaining
to any opacity
or pattern of opacities
presumed
to represent
fibrous tissue-Evaluation:
2. An inferred conclusion usually used as a radiobogic descriptor.
Acceptable
if used in strict accordance
with the
criteria cited under fibrosis
(vs.).
fIlm, n, -a. RSdiOL 1. The generic term for a radiahon-recording
medium
consisting
of a photonsensitive emulsion
coated on a flexible cellulose
acetate or Mylar support. 2. A specific radiationrecording medium coated with an identified emulsion and having particular,
predictable
imaging
properties.
(This
film is more sensitive than
that.”) 3. A unit or sheet of such a radiation
recording medium. 4. A processed
radiograph
(col!oq).-Evaluation:
Film properly refers to the
unexposed,
unprocessed
raw material
of radi-
ographic
recordings;
radiograph
properly
refers
to the exposed,
processed
product
of radiographic recording.
The use of film as a synonym
for radiograph
in referring
to an exposed and
processed
diagnostic recording is not recoinmended.
-v,
-ad, -ing. Radio!.
To record or examine
radiographically;
to expose a radlograph.-Syn-
onyms: to x-ray, to radiograph, to expose a radiograph, to record a radiograph-Evaluation:
Film in this sense is usually used in contradistinction to screen, to distinguish a radiographic from
a fluoroscopic
procedure. Its use is acceptable
(particularly
in British usage), but to expose a
radiograph
is preferred.
film contrast
factor,
n. Radio! phys. The slope of
the film characteristic curve (a plot of density vs.
bog relative exposure); hence, the rate of change
of film blackening (optical density) as a function
of exposure-Synonyms:
film gamma, film gradent; these terms are not strictly synonymous
with film contrast factor, but are closely related
to it in meaning-Evaluation:
A fundamental
characteristic
of a radiographic emulsion.
filter, n, -s. 1. Radiolphys. A device (usually sheet
aluminum or copper) placed in the primary x-ray
beam for the purpose of preferentially absorbing
low-energy
photons that otherwise
would be absorbed by the patient. 2. A shaped metallic absorber placed in the primary x-ray beam to attenuate certain areas of the beam preferentially. See
trough filter-Qualifiers:
1. primary, secondary,
mherent, added; 2. trough, wedge.
filtration,
n. RadiO! phys. The process of attenuatrng the x-ray beam preferentially
with respect to
photon energy and/or spatial distribution-Qua!ifiers: inherent,
added, total-Evaluation:
A fundamental concept
of radiation physics of clinical
iniportance
in radiation
protection.
fissure, n, -S. 1. Mat. Any cleft or infolding of the
surface of a structure; hence, in the lungs, the
mfolding of visceral pleura that separates
one
lobe or part of a lobe from another. a. Interlobar
fissures are produced
by two layers of visceral
pleura. b. Anomalous
fissures may be complete
or incomplete, usually separate segments rather
than lobes and, in the case of the azygos fissure,
may be formed by two layers of visceral and
parietal pleura. 2. Radio!. A linear opacity normally
1 mm or less in width that corresponds
in position
and extent to the anatomic separation of pulmonary lobes or segments-Qualifiers:
minor, major, horizontal,
oblique,
accessory,
anomalous,
azygos, inferior accessory-Synonym:
la. interlobar septa.-Eva!uation:
2. A specific feature of
radiobogic
anatomy; an appropriate and useful
term.
Flelschner line, n, -a. Radio!. A straight, curved, or
rregular
linear opacity that is Visible in multiple
projections;
is usually situated in the lower half
of the lung; is usually approximately
horizontal,
but may be oriented in any direction; and may or
may not appear to extend to the pleural surface.
AJR:143,
FLEISCHNER
September1984
Such lines vary markedly
in length and width;
their exact pathologic significance
is unknown.Qualifiers:
In radiologic description, the location,
length. width, and orientation of such a line
should
be specified-Synonyms:
None; platelike, discoid, and platter atelectasis
should not be
used as synonyms. In the absence
of clear histologic evidence
of the significance
of F. lines,
this inferred
identification
of such lines with a
form of atelectasis is unwarranted-Evaluation:
An acceptable term. The term linearopacity
properlyqualified with respectto location, dimensions,
and orientation
is to be preferred, however.
fluffy, adj. Radio![said of opacities]. Poorly defined,
lacking clear-cut
margins;
resembling
down or
fluff. -Synonyms:
shaggy,
poorly defined.
Evaluation: An imprecisedescriptoroflimited
usefulness.
fluid bevel, n. Radio!. The shadow complex
produced by a horizontal x-ray beam traversing
a
space containing
both gas and liquid or, less
often, two liquids of different
attenuation
char-
acteristics.
Hence, a horizontal
interface between
zones of relative lucency above and opacity be-
low. -Synonyms:
air-fluid level (fluid level is proferred), gas-fluid level, gas-liquid level. -Evaluation: A useful and acceptable descriptor.
G
gas shadow,
n. 1. Pathophysiol/Clin.
A shadow of
such exceptional lucency relative to adjacent anatomic shadows and to the inferred thickness of
the absorber
as to exclude
the possibility
of its
representing
a solid or liquid absorber. -Evaluation: An inferred conclusion
appropriately based
on radiographic
descriptor.
ground-glass,
evidence alone and useful as a
adj.
Radio!
ance]. Any extended,
[usually
with
appear-
finely granular pattem
of
pulmonary
opacity within which normal anatomic
details are partly obscured;
from a fancied resemblance to etched or abraded glass. -Evaluation:
A nonspecific
radiologic descriptor oflimited usefulness.
H
heart failure, n. 1. Pathophysio!/Cin.
Inability of the
heart to satisfy the circulatory needs of the tissues of the body without raising ventricular enddiastolic pressure above 1 2 mm Hg, even though
filling pressures
may be adequate. 2. Radio!. The
presence
within the thorax of a complex of signs
of pulmonary
or systemic
venous hypertension
pul-
including,
but not limited to, cardiomegaly,
monary bboodflow
redistribution,
interstitial
and/
or alveolar edema, generalized decrease in pubmonary volume, and, in the case of right ventricular failure only, generalized systemic venous
distension.
-Qualifiers:
Expressing course of
development:
acute, chronic. Expressing nature
of involvement:
left, right, biventricular.
-Synonyms: cardiac decompensation,
cardiac failure,
congestive
heart failure. -Evaluation:
1. An acceptabbe term used in the clinical and pathophysiobogic sense. 2. An inferred conclusion justified
by the presence of cited radiographic findings in
an appropriate clinical setting. Cardiac decompensation or congestive heart failure are the proferred terms.
hernia,
herniation,
n. Clin/Patho! anat/Radio!.
The
protrusion
of all or part of an organ or tissue
through
an abnormal opening. -Evaluation:
An
inferred
conclusion
to be used only within the
precise terms of the definition.
Thus, the word is
appropriate
in relation to a diaphragmatic
hernia,
SOCIETY
513
GLOSSARY
but should not be used with reference to pulmonary overinflation with mediastinal
displacement.
hilum, n, -a. 1. Anat. A depression or pit in that part
of an organ where the vessels and nerves enter.
2. Radio!. The composite shadow at the root of
each lung produced
by bronchi, arteries and
veins, lymph nodes, nerves, brOnChial vessels,
and associated areolar tissue.
-Synonyms:
hilus, -I, lung root. -Evaluation:
2. A specific
element ofradiologic
anatomy.
Hilum and hila are
preferred to hilus and hili. -adj.
hilar.
homogeneous,
adj. Radio!. Of uniform opacity and
texture
throughout.
-Antonyms:
inhornogeneous,
nonhomogeneous,
heterogeneous. Evaluation: An acceptable radiologic descriptor.
lnhomogeneous
is the preferred
antonym
as a
descriptor
of radiographic shadows. -n. homey.
honeycomb
pattern.
n. 1. Patho!. A multitude of
irregular cystic spaces in pulmonary
tissue that
are generally lined with bronchiolar
epithelium
and have thickened
walls composed
of dense
fibrous tissue, with or without areas of chronic
inflammation.
2. Radio!. A number of closely ap-
proximated ring shadows representing air spaces
5-10 mm in diameter with walls 2-3 mm thick
that resemble a true honeycomb;
a finding whose
occurrence
implies
“end-stage
lung. -Synonyms: None; coarse reticular pattern and coarse
reticulonodular
pattem are sometimes
used as
synonyms,
but are inaccurate
descriptors
in this
context and are not recommended.
-Evaluation:
A radiobogic desctiptorthat
has been loosely used
in the past and, therefore,
with imprecise
meaning. It is recommended
that it be used strictly in
accordance
with the dimensional
limits cited
above, in which case it will have specific significanoe.
Hounsfield
unit, n, -a. Radio!phys.
The unit (‘/ooo)
of an arbitrary scale on which the x-ray attenuahon of air, water, and compact bone are defined
to be -1000,
0, and +1000, respectively. Each
such unit represents 0.1% difference
in attenuation with respect to that of water. Abbr: H.
hyperemia,
n. 1. Patho!. An excess of blood in a
part of the body; engorgement.
2. Physiol. Increased
blood flow as part of the inflammatory
response.
3. Radio!. Apparent
increase in number
or caliber of small vessels secondary to an inflammatory process.
ynonym: pleonemia.
-Eva!uation: An inferred conclusion
appropriately
used
as a descriptor only in arteriography.
adj.
hyperemic.
hypertension,
n. Clin. Greater than normal systolic
and/or diastolic
pressure
within the systemic
or
pulmonary
vascular bed. Generally accepted empirical boundary
levels are as follows: systemic
arterial
h., >1 40 mm Hg systolic, >90 mm Hg
diastolic; systemic
venous h., >12 mm Hg; pul-
monary arterial h., >30 mm Hg systolic, >15
mm Hg diastolic; pulmonary
venous h., >1 2 mm
Hg. -Evaluation:
An inferred conclusion, but oxcept in the case of systemic arterial hypertension,
it can be approximated
the basis of radiologic
with
useful
accuracy
on
evidence.
infarct, n, -S. 1. Patholanat.
a. A region of ischemic
necrosis surrounded
by hyperemic tissue resultmeg from occlusion
of the region’s feeding vessel,
usually by an embolus;
a complete
infarct. b. A
region of tissue injury and hemorrhage
resulting
from occlusion
usually
Radio!.
of the region’s
temporal development
sidered
feeding vessel,
by an embolus;
an incomplete infarct. 2.
A pulmonary
opacity that by virtue of its
to result
and clinical setting is con-
from thromboembolic
occlusion
of a feeding vessel. Such an opacity is commonly,
but not exclusively,
hump-shaped
and pleuralbased when seen in profile; poorly defined and
round when viewed en face. (Subsequent
events
may establish that the opacity was the result of
either hemorrhage
or tissue necrosis.)
-Synonym: infarction.
-Evaluation:
1. Infarct is proferred to infarction in this sense. 2. An inferred
conclusion,
which, in the proper clinical sethng,
may be based
on the radiograph.
The word
should not be used in the absenceof
a pulmonary
opacity.
-V.
-ad. Pathol. To produce an infarct, def. 1
above.
infarction,
n, -a. 1. Pathol physiol. The process of
infarct formation.
2. Patho! anat. An infarct.
bnflhtrate, n, -a. 1. Pathophysiol.
a. Any substance
or type of cell that occurs within or spreads
through the interstices (interstitium
and/or alveoli)
of the lung, that is foreign to the lung, or that
accumulates
in greater
than normal
quantity
within it. b. An accumulation
of such a substance
or type of cell. 2. Radio!. a. A poorly defined
opacity in the lung that neither destroys
nor displaces the gross morphology
of the lung and is
presumed
to represent an infiltrate in the pathophysiologic
sense. b. Any poorly defined opacity
in the lung. -Evaluation:
Majority:
An inferred
and often unwarranted
conclusion
used as a
descriptor. The term is almost invariably used in
sense 2b, in which it serves no useful purpose,
and lacking a specific connotation
is so variably
used as to cause great confusion. Its use as a
descriptor
is to be condemned.
Minority:
Were
the term to be used in strict accordance
with
definition
2a, it would be a useful descriptor
to
distinguish
processes
that do not distort lung
architecture
from expanding
processes
that do.
-v.
1. To penetrate
the interstices
of. 2. To
spread or cause to spread by infiltration.
infiltrated,
adj. 1. Having entered
or spread
by
penetration
of the interstices of a tissue. 2. Hayrng undergone
infiltration.
infiltration,
n. 1. The process by which substances
and/or cells spread through lung tissue via its
mterstices
without
destroying or displacing its
normal architecture.
2. See infiltrate.
def. lb.
inflate, v. To expand, to swell with gas.
inflated,
adj. Expanded
or filled with gas. -Qualitiers: See below.
inflation,
n. Ptiysio!/Radio!.
The state or process of
being expanded
or filled with gas; used specifically with reference to the expansion
of the lungs
with air. -Qualifiers:
over- (preferred) or hyper-;
under- (preferred) or hypo-.
ynonyms: aeraton, inhalation,
inspiration,
ventilation.
Inflation
connotes expansion
with gas or air. Aeration
connotes
the admission
of air, exposure to air.
Inhalation refers specifically
to the act of drawing
air into the lungs in the process of breathing (as
opposed
to exhalation); and inspiration with reference to breathing, is similar in connotation.
Ventilation
connotes both the intake and expubsin of air from the lungs. -Evaluation:
The word
inflation avoids the confusion that surrounds the
meanings
of aeration
and ventilation
as a result
of common
misusage.
It is the preferred
term.
interface, n. Radio!. The boundary
between
the
shadows of two juxtaposed
structures or tissues
of different texture or opacity. -Synonyms:
edge. border, silhouette,
junction.
-Evaluation:
A useful radiologic descriptor.
interstitlum,
n. l.Anat/Radio!.
Acontinuum
of loose
connective
tissue throughout the lung comprising
three subdivisions:
(i)
the bronchovascular
(ax-
lab), surrounding
the bronchi, arteries, and veins
from the lung root to the level of the respiratory
bronchiole;
(2) the parenchymal
(acinar). situated
between alveolar and capillary basement
mombranes; and (3) the subpleural,
situated
beneath
514
FLEISCHNER
the pleura as well as in the interlobar
septa. Synonym: interstitial
space. -Evaluation:
A useful anatomic term. The interstitium
of the lung is
not normally visible radiographically;
it becomes
visible only when disease(e.g., edema) increases
its volume and attenuation. -adj.
Interstitial.
K
Kerley
line,
A septal
depending
n, -5 [usually in the plural]. Radio!. a.
line (q.v.). b. A linear opacity, which,
on its location,
extent,
and orientation,
may be further classified as follows: K. A line: An
essentially straight linear opacity 2-6 cm long
and 1 -3 mm wide, usually situated in an upper
lung zone, that points toward the hilum centrally
and is directed
toward, but does not extend to,
the pleural
surface
peripherally.
K. B line: A
straight linear opacity 1 .5-2 cm long and 1-2mm
wide, usually situated at the lung base and orb-
ented at right angles to the pleural surface with
which it is usually in contact
peripherally. K. C
lines [always in the plural]:
linear opacities
producing
A group
of branching,
the appearance of a
fine net, situated at the lung base and representing K. B lines seen en face. -Synonyms:
septal
lines, lymphatic
lines.
Except
when
it is essential
to distinguish A, B, and C lines, the term seota!
line is to be preferred. Lymphatic line is anatomically inaccurate
and should never be used. Evaluation: A specific feature of pathologic/radiologic anatomy. An acceptable but not preferred
term.
L
line, n. Radio!. An extended longitudinal
shadow (in
the lung or mediastinum, an opacity) no greater
than 2 mm in width; cf. stripe. -Evaluation:
A
useful term appropriately used in the description
of radiographic shadows within the mediastinum
(e.g., anteriorjunction
line)orlung(e.g.,
interlobar
fissures).
linear opacIty,
bling a line;
Radio!. A shadow resemany elongated
opacity
of
approximately uniform width. -Qualifiers:
The
length, width, anatomic
location,
and orientation
of such a shadow
should be specified.
-Synonyms: line, line shadow,
linear shadow,
band
shadow.
Band shadow
and line shadow
have
been used by some to identity elongated shadows more than 5 mm wide and less than 5 mm
wide, respectively.
Linear opacity qualified
by a
statement
of specific dimensions
is to be proferred. -Evaluation:
Ageneric
radiologicdescnptor of great usefulness. The term includes a variety of linear shadows whose anatomic
location,
orientation,
and dimensions
imply their specific
anatomic or pathologic significance
(e.g., septal
lines). Unear opacity is to be preferred to more
specific anatomic or pathologic
terms (e.g., discold atelectasis),
unless the true nature of the
SOCIETY
GLOSSARY
The terminal unit of an acinus; the part
of the lung distal to the terminal respiratory
bronchiole. It comprises alveolar ducts, alveolar sacs,
Primary:
alveoli, and their accompanying
blood vessels,
lymphatics,
and supporting tissues. 2. Secondary: A variable
number of acini (usually 3-5)
bounded, in mostcases,
bythin connective tissue
septa. -Evaluation:
1. Acinus is the preferred
anatomic/physiologic
unit of lung structure.
2.
The word lobule when unmodified
refers to a
secondary
lobule. The concept
of the primary
lobule as defined has been largely abandoned.
bocal, adj. Radio!. Occupying orconfined
toa limited
space within a defined
structure;
cf. circumscribed.
-Synonyms:
localized,
focal. -Mtonyms: generalized,
general, widespread.
-Evaluation: An acceptable
descriptor.
lucency.
n, -lee. Radio!. 1. The capacity to transmit
light (translucency);
hence, by extension,
the capacity to transmit x-radiation. 2. The degree of x-
AJR:143,
discrete pulmonary
opacities
that are generally
uniform in size and widespread
in distribution
and
each of which is 2 mm or less in diameter. Synonym: micronodular
pattern. -Evaluation:
An
acceptable
descriptor
without
causative
connotation.
mucold impaction,
n. Pathol/Radiol.
A broad linear
and/or branching
opacity
(I-, Y-, or V-shaped)
caused by the presence
of thick, tenacious mucus within a proximal airway (bobar, segmental,
or subsegmental
bronchus)
and usually associated with airway dilatation. -Evaluation:
An inferred conclusion
without precise causative connotation. A useful descriptor.
MiiIer
maneuver,
n. Physiol. Inspiration against a
closed glottis, usually, but not necessarily, from
a position of residual volume, for the purpose of
producing transient decrease in intrathoracic
pressure.
ray transmission of an object, usually expressed
in terms of transmission of one object relative to
another.
3. The shadow of an absorber that
attenuates
the primary
x-ray beam less effectively than do surrounding
absorbers.
Hence, in
a radiograph, any circumscribed area that appears more nearly black (of greater photometric
density) than its surround. Usually applied to the
shadows
of air or fat when surrounded by more
effective absorbers such as muscle, exudate, etc.
ynonyms:
translucency,
transradiancy.
Evaluation: This term, used by analogywith opecity, is acceptable in American
usage, although
it
is etymobogically
indefensible.
In British usage,
transradiancy
is preferred.
lucent, adj. Radio!. Capable of transmitting
radiant
energy; specifically, x-radiation.
lymphadenopathy,
n. Clin/Patho! anat/Radiol.
Any
abnormality
of lymph nodes; by common usage,
usually restricted
to enlargement oflymph nodes.
-Synonyms:
lymph
node enlargement
(proferred), adenopathy.
-Evaluation:
Lymph nodes
are not glands. Lymphadenopathy
and adonopathy are, therefore,
inappropriate
terms and
any reference to lymph glands is to be condamned.
N
nodular pattern,
n. Radio!. A cOllection of innumerable, small, roughly circular, discrete
pulmonary
opacities
ranging in diameter
from 2 to 10 mm,
generally uniform in size, widespread
in distribution, and without marginal spiculation;
cf. reticubonodular
pattern.
-Evaluation:
An acceptable
radiologic
descriptor
without
specific
pathologic
or causative implications. The size of the nodules
should be specified,
either as a range or as an
average.
nodule,
n, -s. 1. Morphol/Gen’l
med. Any small,
nearly spherical
collections
of differentiated tis-
sue. 2. Radio!. Any pulmonary
is incomplete.
2. Radio!. One of the principal
divisions of the lungs (usually three on the right,
two on the left) that are separated in whole or in
part by pleural fissures.
lobular,
adj. Anat. Of or pertaining to a pulmonary
lobule.
lobule,
n, -a. Mat.
A unit of lung structure. 1.
or pleural lesion
represented
in a radiograph
by a sharply defined,
discrete,
nearly circular opacity 2-30 mm in diameter. - Qualifiers: Should always be qualified
with respect to size, location, border characteristics, number,
and opacity.
-Synonym:
coin
lesion (q.v.); cf. mass.
-Evaluation:
A useful
and recommended
descriptor to be used in preference to coin lesion.
n, -*5.
hence,
shadow is known or can be inferred with reasonable certainty.
bobar, adj. Anat/Radiol. Of or pertaining to a lobe.
lobe, n, -5. 1. Mat/Radio!.
One of the principal
divisions of the lungs (usually three on the right,
two on the left) each of which is enveloped by
visceral pleura except at the lung root and in any
area of developmental
deficiency
where a fissure
September1984
0
M
n. 1. Physio!. Less than normal blood flow
to the lungs or a part thereof. 2. Radio!. General
or local decrease
in the apparent width of visible
pulmonary
vessels, suggesting less than normal
blood flow. -Qualifiers:
acute, chronic, local,
general.
-Synonym:
reduced
blood flow. Evaluation: An inferred conclusion appropriately
based on the radiographic
appearance
and usually used as a descriptor. An acceptable term. adj.OligemiC.
opacIty.
n. -bee. Radio!. 1. ImpervIousness
to raoligemia,
n, -S [usually in the plural]. Radio!. A
descriptor
variously
used with reference
to: (1) the shadows produced
by normal pulmonary blood vessels; (2) the shadows produced by
a combination of normal pulmonary
structures
(blood vessels,
bronchi,
etc.), or (3) abnormal
pulmonary
shadows
of no specific characteristics
of significance. -Synonyms:
opacity,
[usually]
linear opacity. Qualifiers: The type, dimensions, and anatomicdistribut,on
of such shadows
should be specified
(e.g., bronchovascular,
trabecular). The term should not be used without
qualification. -Evaluation:
When used alone, a
vague descriptor
of no value; not recommended.
With proper qualifIcation,
the term is acceptable,
but opacity or shadow is usually to be preferred.
mass, n, -es. 1. Morpho!/Gen’lmed.
Any cOllection
of tissue differentiated from surrounding tissues.
2. Radio!. Any pulmonary or pleural lesion reprosented
in a radiograph by a discrete opacity
greater than 30 mm in diameter
(without
regard
marking,
vague
to contour, border characteristics,
or homogeneity). but explicitly
shown or presumed
to be cxtended
in all three dimensions. -Qualifiers:
Should always be qualified with respect to size,
location, contour,
definition,
homogeneity,
opacity, and number. -Synonyms:
None; of. nodule.
-Evaluation:
2. A useful and recommended
doscriptor.
mlliary
pattern,
n, -a. Radio!. A collection
of tiny
dent energy; specifically,
x-rays; the capacity to
attenuate
an x-ray beam. 2. The degree of x-ray
attenuation
produced
by an absorber, usually
expressed in terms of the attenuation
of one
absorber
relative to another. 3. The shadow of
an absorber that attenuates the x-ray beam more
effectively
than do surrounding
absorbers.
Hence, in a radiograph, any circumscribed
area
that appears more nearly white (of lesser photometric density) than its surround. Usually applied
to the shadows
of nonspecific
pulmonary
colbections of fluid, tissue, etc., whose attenuation
cxcoeds that of the surrounding aerated lung. Synonym: 3. radiopacity;
cf. density.
-Evaluation: 3. An essential and recommended
radiobogic
descriptor. In the context of radiologic reporting,
radiopaque
is acceptable but appears redundant,
particularly
since radio- does not serve to distinguish between
the opacity of an absorber
to xrays and opacity
of a radiographic shadow to
AJR:143,
September
FLEISCHNER
1984
visible light rays. Radiopaque is preferred in Butish usage, nevertheless.
Density
(q.v.) should
never be used in this context.
opaque,
n, -S. Radio!. That which is opaque (Webster). Specifically,
a contrast
medium
that is
opaque
to x-rays. -Synonyms:
contrast
mediem, contrast
agent, contrast material. -Evaluation: A concise and acceptable
term. Contrast
medium, agent, and material are preferred, however. NB.: The terms contrast
and contrast media (when referring
to a single agent) are colboquial, grammatically
incorrect,
and should not be
used. -adj.
Radio!. Impervious
to x-rays. Synonym:
radlopaque. -Evaluation:
Opaque and
radiopaque
are both acceptable terms; opaque is
preferred.
See opacity.
ossific,
adj. Of or pertaining to bone.
ossification,
n, -5. The state or process
of being
ossified. Specifically:
pulmonary
ossification,
n.
1. Pathophysiol.
a. The process
by which trabecubar bone is formed within lung tissue. b. The
state in which trabeCUlar bone exists within the
lung tissue. c. A mass orfocus of trabecular bone
occurring
in lung tissue. 2. Radio!. Cabciflc opac.
ities within the lung that represent
trabecular
bone; applicable to disseminated
calcific opacities
that (1) display
morphologic
characteristics
of
frabectiar
bone (i.e., trabeculation and a defined
cortex) or, more often, (2) occur in association
with a lesion known histologically
to produce
trabectilar
bone within lung (e.g., mitral stenosis).
-Synonyms:
ossific
nodulation,
ossific
nodube(s). -Evaluation:
2(i). A primary radiobogic
diagnosis.
2(2). An inferred conclusion.
In either
case, a useful radiobogic term; to be distinguished
from pulmonary calcification.
ossified,
adj. Having been changed into bone.
ossify, v. To change into or form bone.
p
parasplnal
line, n, -s. Radio!. A vertically oriented
interface
usually
seen in a frontal chest radiograph to the left and rarely to the right of the
thoracic
vertebral
column.
It extends from the
aortic arch to the diaphragm and represents contact between
aerated lung (of a lower lobe) and
adjacent mediastinal
tissues. On the left, the
anatomic
interface
is situated
posterior
to the
descending
aorta, and its radiographic shadow is
usually seen between the left lateral margins of
the aorta and spine. -Synonyms:
left paraspinal
pleural
reflection,
left paraspinal interface. Evaluation: A specific feature in radiobogic anat-
omy. Either of the synonyms cited is preferred to
paraspinalline,
inasmuch
as the shadow, in fact,
represents
an interface,
not a line.
parenchyma,
n. 1. Anat. The gas-exchanging
part
of the lung consisting
of the alveoli and their
capillaries,
estimated to constitute about 90% of
total lung volume. 2. Radio!. The lung exclusive
of visible pulmonary vessels and airways. Evaluation: A useful anatomic concept.
An acceptable
radiologic
descriptor.
-adj.
parenchymatous.
phantom
tumor,
n, -s. Radio!. The shadow
produced by a local COlleCtiOn of fluid in one of the
interbobarfissures,
usually possessing an elliptical
configuration
in one projection
(e.g.. the lateral)
and a round configuration
in the other (e.g.. the
frontal view). It is commonly caused by cardiac
decompensation
and usually disappears
after appropriate therapy. -Synonyms:
vanishing tumor,
pseudotumor.
-Evaluation:
A diagnostic
conclusion that can only be inferred from a single radiograph, but may be explicit by the presence of
serial radiographs.
In the latter case, it is an
acceptable
radiobogic descriptor.
plateilke
atelectasls,
n. Radio!. A linear or planar
SOCIETY
GLOSSARY
opacity
of uncertain significance,
presumed
to
represent
diminished
volume in part of the lung
seen end-on. -Synonyms:
platter, linear, or discold atelectasis. -Evaluation:
An inferred conclusion,
usually not subject
to proof and often
unwarranted.
Its use as a descriptor is not recommended.
Linear opacity,
planar opacity,
etc.
are preferred.
pleonemla,
n. 1. Physiol.
Increased blood flow to
the lungs or a part thereof. 2. Radio!. General or
local increase
in the apparent
width of visible
pulmonary vessels, suggesting
greater than nor-
mel blood flow. -Synonyms:
hyperemia, increased
blood flow. -Evaluation:
An inferred
conclusion
appropriately
based
on the radiographic
findings alone. Because
pleonemia
serves
to distinguish
increased
blood flow of
other causes from increased
blood flow resulting
from inflammation
(hyperemia),
it is the preferred
term in this sense. -adj.
pbeon.mlc.
pneumatocele,
n, -s. 1. Pathol anat. a. A thinwalled. gas-filled
space within the lung, usually
occurring
in association
with acute pneumonia
(most commonly
of staphybococcal
origin) and
almost invariably transient. b. A form of pulmonary air cyst. 2. Radio!. An approximately round,
transient
lucency within the lung that is usually
associated with, arid adjacent to, a zone of resolving pulmonary
consolidation
that is presumed
to represent a pneumatocele in the pathologic
sense. -Evaluation:
2. An inferred conclusion.
An acceptable descriptor only if used in accordance with the precise definition.
pneumomedlastlnum,
n. 1. Patho!. A state characterized
by the presence
of gas in mediastinal
tissues outside the esophagus
and tracheobronchial tree. 2. Radio!. The presence ofone or more
gas shadows within the mediastinum that do not
correspond
in position
and contour
with gas in
the esophagus
or tracheobronchial
tree. -Qua!ifiers:
spontaneous,
traumatic,
diagnostic.
Synonym: mediastinal
emphysema.
-Evaluation: A diagnostic conclusion
appropriately
based
on radiologic findings alone. Pneumomediastinum
is preferred to mediastinal
emphysema.
pneumonia.
n, -s. 1. Pathol. Infection
of lung parenchyma
and/or interstitium.
2. Radio!. COnSOIidation or any ofvarious otherforms
of pulmonary
opacification
presumed
to represent pneumonia
in the pathologic
sense. -Synonym:
pneumonitis. -Qualifiers:
Expressing
temporal
course:
acute, chronic. Expressing type of pulmonary
involvement: airspace, bobar, interstitial, broncho(pneumonia
plus bronchitis).
Expressing
cause:
bacterial,
viral, fungal.
mycoplasma.
-Evaluation: An inferred conclusion; pneumonia
is the
preferredgeneric term.
pneumoperlcardium,
ni. Pathol. A state characterized by the presence of gas within the pericardial space. 2. Radio!. The presence of gas within
the pericardium;
visible only where the gas
shadow
is seen in profile: laterally in the frontal
view, anteriorly
or posteriorly
in the lateral projection. -Evaluation:
A diagnostic conclusion
appropriately
based on radiobogic findings alone.
pneumothorax,
n, -aces. 1. Pathol. A state characterized
by the presence
of gas within the
pleural space. 2. Radio!. The presence
of a gas
shadow
between
the peripheral
margin of the
lung (visceral
pleura) and the chest wall, ciaphragm, or mediastinum(parietal
pleura). -Qualifiers: spontaneous,
traumatic, diagnostic,
tension. -Evaluation:
A diagnostic
conclusion
appropriately
based on radiobogic evidence alone.
popcorn
calcification,
n. Radio!.
A cluster of
sharply
defined,
irregularly
lobulated,
calcific
opacities suggesting
the appearance
of popcorn.
-Evaluation:
An acceptable
descriptor.
posterior
junction
line, n. Radio!. A vertically
oilented, linear or curvilinear opacity about 2 mm
515
wide, commonly
projected
shadow and usuaNy slightly
on the
concave
tracheal
air
to the right.
it is produced by the shadows of the right and
left pleurae in intimate contact between
the aeratod lungs. It represents the plane of contact
between
the lungs posterior
to the esophagus
and anterior
to the spine; hence, in contrast to
the anterior
junction
line, it may extend
both
above and below the suprastemal
notch and may
be seen above and/or
below the azygos
and
aortic arches. -Synonyms:
posterior
mediastinal
septum, posterior
mediastinal
line. -Evaluation:
A specific feature of radlologic
anatomy.
to be
preferred
to the synonyms.
posterior
tracheal
stripe,
n. Radio!. A vertically
oriented, linear opacity ranging in width from 2 to
5 mm, extending from the thoracic inlet to the
bifurcation
ofthetrachea
and visible only in lateral
radiographs
of the chest. It is situated between
the air shadows
of the trachea and the right lung
and is formed by the posterior
tracheal wall and
contiguous
mediastinal
interstitial
tissue. -Synonym: posterior tracheal band. -Evaluation:
A
specific feature of radiologic
anatomy.
Posterior
tracheal stripe is preferred
to posterior
tracheal
band.
primary
complex,
n. 1. Pathol. The combination
of
a focus of pneumonia produced by a primary
mfection
(e.g., tuberculosis or histoplasmosis)
with granubomas
in the dralnrng hilar or mediastinal lymph nodes. 2. Radio!. a. The combination
of one or more irregular pulmonary
parenchymal
opacities of variable extent and location assumed
to represent
consolidation
with enlargement
of
the draining hilar or mediastinal
lymph nodes; an
appearance
assumed
to represent an active infection.
b. The combination
of a small, sharply
defined parenchymal
opacity(often calcified) with
calcification
of the &alning hilar or mediastinal
lymph nodes; an appearance
usually regarded
as
evidence
of an inactive process. -Synonyms:
Rankecomplex.
Ghon complex. Primary complex
is to be preferred
to Ranke complex,
which is
acceptable
but rarely used, and Ghon complex,
which represents
an inappropriate
use of the
eponym
and is unacceptable. -Evaluation:
A
useful inferred conclusion.
profusion,
n. Radio!. I. A qualitative
expression
of
the number
of small opacities
per unit area or
zone of lung. 2. In the ILO/1980
classification
of
radiographs
of the pneumoconioses.
the quaIlflora 0 through 3 subdIvide
the profusion
of small
rounded
and small irregular opacities into four
major categories.
These may be further subdivided to provide a 12 point scale: -/0,0/0,0/1;
1/0,1/1,1/2;2/1, 2/2, 2/3; 3/2, 3/3, 3/k.
pseudocavlty,
n, -lee. Radio!. Any shadow cornplex that has the appearance
of a gas-containing
spacewithin
a zoneofconsolidation,
a pulmonary
mass, or a nodule when, in fact, no such space
exists; hence: 1. A central lucency within a nodule
or mass that is proved by computed tomography
or pathologic
examination
to represent lipid. 2.
An apparently
circumscribed lucency created by
the confluence
of shadows of normal anatomic
structures,
most commonly ribs and pulmonary
vessels, that does not, in fact, represent a cavity.
-Synonyms:
2. composite
shadow,
spurious
cavity. -Evaluation:
1. An inferred
conclusion,
sometimes
used as a descriptor.
The term is
without causative connotation.
Its use is not rec-
ommended.
pulmonary
blood flow resthbution,
n. 1. Physiol.
Any departure
from the normal distribution of
blood flow in the lungs, whether
physiologic or
pathologic.
2. RadiO!. Narrowing
and reduction
in
the number of visible pulmonary vascular
shadows in one or more lung regions associated
with
corresponding
widening
and increase in the numbar of Visible pulmonary
vascular shadows in the
516
FLEISCHNER
remaining lung regions. -Evaluation:
An inferred
conclusion,
often used as a descriptor and appropriately based on radiographic
evidence alone.
pulmonary
edema,
n. 1. Pathophysiol.
The accumulation of fluid in the interstitial compartment
of
the lung with or without associated
alveolar filling.
Specifically, the accumulation
of water, protein,
and solutes (transudate) usually due to (1) ricreased
pressure in the microvascular bed; (2)
increased
microvascular permeability;
or (3) impaired lymphatic drainage. Also, the accumulation of water, protein, solutes, and inflammatory
cells(exudate)in
response to inflammation
of any
type (e.g., infection,
hypersensitivity,
trauma. or
circulating
toxins). 2. Radio!. An inferred conclusion applicable
to a pattern of opacity (often
bilaterally
symmetric
and perihibar in distribution)
believed to represent
alveolar filling and/or interstitial thickening
when associated
findings
and/
or history suggest one of the processes enumerated above.
ualifiers: I. Interstitial
edema:
pulmonary
edema confined to the interstitial cornpartments
of the lung; initially the bronchovascuber interstitial space and its continuum,
subsequently the alveolar wall interstitial space. Alveolar edema: pulmonary edema involving the alveoli
as well as the interstitial space. Synonyms:
2.
Wet lung, boggy lung. moist lung. drowned lung.
-Evaluation:
An inferred conclusion
often used
as a descriptor. A useful and acceptable
term
when used in an appropriate
clinical setting. The
synonymous
terms
are colloquialisms
to be
avoided.
pulmonary
perfusion,
n. 1. Physiol. The passage
of blood through the vessels of the lung or a part
thereof.
2. Radio!. Any radiologic evidence of
pulmonary
blood flow in the physiologic
sense. It
may be explicit (in the case of pulmonary angiography) or inferred (in the case of conventional
radiography). -Synonym:
pulmonary
blood flow.
-Evaluation:
a physiologic conclusion
that can
properly be based on, or inferred from, radiobogic
evidence
alone.
A useful and recommended
term.
R
radiographic
contrast,
n. Radio! phys. 1. The difference in optical density between two specified
shadows (usually adjacent) in a processed
radiograph.
2. The resultant of film contrast and
subject
contrast.
-Evaluation:
A fundamental
concept of radiologic physics,
useful in a clinical
context as one determinant
of radiographic
qualIty.
radiographic
quality,
n. 1. Radio!. An expression
of the acceptability
of a diagnostic
radiograph
to
the interpreter;
a subjective
evaluation.
2. Radio!
phys. An expression of the correspondence
between the physical characteristics
of a radiograph
and some predefined
standards,
usually with respect to contrast,
resolution,
and density;
an
objective
evaluation.
-Synonym:
film quality. Evaluation: A useful concept, but only in a loose,
qualitative sense. The term defies precise quantitative definition
and is not in either sense an
expression
diograph.
of the diagnostic
usefulness
of a ra-
radlologic
sign, n, -s. Radio!. A shadow or shadow
complex said to be reliable evidence of a specific
pathologic
state, process, or relation. A list (in-
complete) of specific signs, their reputed significance, and their reliability is as follows: broken
bough 5.: peripheral
bronchial
occlusion
(highly
unreliable).
camabote
5.: echinococcus
cy5t (reliabbe). continuous
diaphragm
s.: pneumomediastinum (usually reliable). crescent
5.: intracavitary
mass; hydatid cyst, fungus ball, etc. (reliable cvidence of an intracavitary mass but not specific
with respect to cause). gloved
finger
s.: bron-
SOCIETY
GLOSSARY
chiectasis
(usually reliable). hibar bifurcation 5.:
vascular vs. extravascubar hilar enlargement
(urnited usefulness).
hllum overlay
5.: cardiomegaly
vs. antenormediastinal
mass(limited
usefulness).
melting
Ice s.: pulmonary
infarction
(limited usefulness).
moon
5.: see crescent
a. 1-2-3 s.:
pulmonary
sarcoidosis
(unreliable;
misleading).
rabbit ear s.: bronchioboalveolar
cell carcinoma
(unreliable).
scimitar s.: partial anomalous pubmonary
venous
return (reliable). sIlhouette
s.:
presence
and localization
of intrathoracic
lesion
(reliable).
tall 5.: see rabbit ear s. (unreliable).
water lily 5.: see camabote
s. (reliable). Westermark s.: pulmonary
embolus(usually
reliable). Evaluation: Signs are seldom as specific as their
authors believe, and their meanings
are often
confused through frequent misuse. Many are unreliable(e.g.,
rabbit ear)or totally erroneous
(e.g.,
1-2-3 sign of sarcoidosis). With the exception of
a few generally recognized and usually reliable
signs (scimitar,
silhouette, Westermark), the use
of signs as
descriptors
is not recommended.
description
of the individual finding
Specific
is
preferred.
residual,
n. Radio!. Any nonspecific
opacity of uncertain cause believed
to represent
an inactive
process.
-Synonym:
scar. -Evaluation:
An intermed conclusion.
The term is vague, grammatically incorrect (residuum
is the noun), and should
be rejected in favor of more precise diagnostic
statements.
-adj.
Of or pertaining
to a residue or remainder.
resolution,
n. 1. Radio.! phys. a. A quantitative
expression
of the number of punctate or linear
absorbers
that can be recorded
as perceptibly
discrete shadows per unit distance across a radiographic
receptor; usually expressed
in line
pairs per millimeter.
(Metallic
wires are usually
used as test objects for such measurements.)
b.
The characteristic
of a radiographic receptor systern that expresses
its ability to record closely
approximated
absorbers
as discrete shadows. c.
The spatial frequency
response of a radiographic
system, usually expressed
in terms of its moduladen transfer function
(MTF). d. A measure
of
the “fidelity
of the imaging system. -Synonym:
resolving
power. -Evaluation:
Resolving power
is technically
the correct
term, but by virtue of
bong usage, resolution
is acceptable
in this sense.
2. Pathol/Radiol.
The process by which a lesion,
specifically
aconsolidation,
clears. It may becomplete or partial. -Evaluation:
An explicit diagnostic statement
appropriately
based on serial radiographs.
respiratory
failure,
n. Physic!. A pathologic
state
resulting
from impaired
respiratory
function
and
characterized
by an arterial Po below 60 mm Hg
or an arterial Pco above 49 mm Hg, in a subject
at rest at sea level. -Qualifiers:
acute, chronic.
-Synonym:
pulmonary
insufficiency.
-Evaluation: A useful term in its clinical and physiologic
usage that should never be used as a radiobogic
descriptor.
It is preferred to pulmonary
insufficiency.
retbcular
pattern,
n, -s [usually
in the singular].
Radio!. A collection
of innumerable
small linear
opacities that together produce an appearance
resembling
a net. -Qualifiers:
fine, medium,
coarse. -Synonym:
Small irregular opacities (in
the lLO/1980
classification
of pneumoconioses).
-Evaluation:
A recommended
descriptor.
It has
no pathologic
connotation
and should
not be
used as a synonym
for interstitial disease of the
lung. The synonymous
term smallirregular
opecities should be restricted
to the radiographic characterization
of pneumoconiosis.
reticubonodular
pattern.
n, -s [usually in singular].
Radio!. A collection
of innumerable small, linear
and micronodularopacities
that together produce
a composite
appearance
resembling
a net with
AJR:143,
September
1984
small superimposed
the reticular
and
sionally of similar
nodules. In common
usage,
nodular
elements
are dimenmagnitude.
-Qualifiers:
fine,
medium,
-Evaluation:
coarse.
An acceptable
radiobogic descriptor
without
specific pathologic
wnplications.
righttracheal
stripe. n. Radio!. A vertically oriented
linear opacity
2-3 mm wide that extends
from
the thoracic
inlet to the right tracheobronchial
angle in the frontal radiograph.
It is situated between the air shadow of the trachea and the right
lung and is formed by the right tracheal wall and
contiguous
mediastinal
interstitial tissue and adjacent
pleura.
-Synonyms:
right paratracheal
stripe or band. -Evaluation:
A specific feature of
radiographic
anatomy.
S
segment,
n, -s. Anat/Radiol.
One of the Principal
anatomic
subdivisions
of the lobes of the lung
(usually 10 on the right and 9 on the left); a lobar
subdivision
served by a major branch of the bobar
bronchus.
-Qualifier:
bronchopulmonary.
segmental,
adj. Mat/Radio!. Of or pertaining to a
segment.
septal line, n, -s [usually in the plural]. Radio!. A
generic term for fine, linear opacities
of varied
distribution produced by the interstitium between
pulmonary
lobules when the interstitium
is thickened by fluid, dust deposition, cellular material,
etc. -Synonyms:
Kerley lines (q.v.), lymphatic
lines; of. interlobar
septum.
Septa! lines is the
preferred term; Kerley lines is acceptable,
particularly when one seeks to identity a particular type
of septal line (e.g., Kerley B lines). Lymphatic
lines is anatomically
an inaccurate
term and
should not be used in this context. -Evaluation:
A specific feature of pathologic radiobogic anatomy. often inferred. A recommended
term.
shadow,
n, -s. Radio!.
1. In clinical radiography,
any perceptible
discontinuity
in film blackening
ascribable
to the attenuation of the x-ray beam
by a specific anatomic absorber or lesion on or
within the body of the patient. An opacity
or
bucency. 2. A similar discontinuity
in any other
diagnostic
visual representation
of the remnant
energy in an x-ray beam after its passage through
the body of the patient (e.g.. a fluoroscopic image, a CAT display, etc). -Qualifiers:
The term
should always be qualified as precisely as possible with respect to size, contour, location, opacity
(lucency),
etc. -Evaluation:
A useful and recommended
descriptorto
be used only when more
specific identifiCatiOn
is not possible.
shaggy heart, n. Radio!. A heart whose border is
partially effaced by multiple small, irregularly distributed
opacities
produced
by any of several
pathologic
processes
affecting
the paracardiac
parts of the lungs and/or pleura. -Evaluation:
This term is an imprecise radiologic
descriptor,
to
be used with caution.
sIlhouette
sign, n. Radio!. 1. The effacement
of an
anatomic soft-tissue border by consolidation
of
the adjacent lung or accumulation
of fluid in the
contiguous
pleural space. 2. A sign of the conformity and, hence, of the probable adjacency
of
a pathologic opacity to a known structure; useful
in detecting
and localizing
a consolidation
along
the axisofthe x-ray beam. -Evaluation:
A widely
accepted
and useful
radiologic
descriptor.
It
should be noted that the finding, in fact, involves
the loss of a silhouette.
small irregular
opacity,
n, -lee [usually used in the
plural]. Radio!. 1. Small pulmonary opacities that
defy classification in terms of simple geometric
descriptors, that are often poorly defined, and
that in large numbers produce an appearance
AJA:143,
FLEISCHNER
September1984
resembling
a
net. 2. In the ILO/1980 classification
of radiographs
of the pneumoconioses,
the qualiflers s, t, and u subdivide
such opacities
into
three categories
on the basis of their greatest
thickness:
s, up to 1.5 mm; t, I .5-3 mm; and u,
3-10 mm. -Synonym:
reticular pattern. -Evaluation: A term to be used specifically
to describe
radiographic
manifestations
of the pneumoconioses. Reticular pattern is preferred when referring to nonpneumoconiotic
disease.
small rounded
opacity,
n, -lee [usually used in the
plural]. Radio!. 1. Innumerable small pulmonary
nodules ranging in diameter from bare visibllity
up to 10 mm. 2. In the lLO/1980
classification
of
radiographs
of the pneumoconioses.
the quailflersp, q, and r subdivide
the predominant
opacIties into three diameter ranges: p. up to 1 .5 mm;
q, 1 .5-3 mm; and r, 3-1 0 mm. -Synonym:
nodular pattern. -Evaluation: A term to be used
specifically
to describe
radiographic manifestotions of the pneumoconioses.
Nodular pattern is
preferred
when referring
to nonpneumoconiotic
disease.
stripe, n, -S. Radio!. An extended
longitudinal,
cornposite
opacity
2-5 mm wide; cf. line, band
shadow,
linear opacity. -Evaluation:
An acceptable descriptor
when used with reference
to
radiographic
shadows within the mediastinum.
subject
contrast,
n. Radio! phys. 1. Quantitative:
The ratio of the intensities
of the remnant radia-
(q.v.). -Evaluation:
differences
in
lesser order than a segmental
bronchus,
but
which islarger than a lobule.
subsegmental,
adj. 1. Anat/Radiol. Of or pertaining
to a subsegment. 2. Radio!. Of or pertaining to
any pulmonary shadow, smaller than a segment
and larger than a lobule, presumed
to represent
a subsegment in the anatomic sense. -Evaluation: An acceptable
radiologic
descriptor.
the
beam that will traverse the lungs of the patient in
ically unless thickened;
arterial walls, unless cal-
These qualifiers
are, therefore,
sential to their description.
-Synonyms:
A common
from
descriptor,
the exposure
of a frontal chest radiograph.
tubular shadow,
n, -s. Radio!. 1. Paired, parallel or
slightly convergent
linear opacities
presumed
to
represent
the walls of a tubular structure or dovice (e.g., a bronchus, vessel. or chest tube, seen
in profile). 2. An approximately
circular opacity
presumed to represent
the wall of a tubular structure or device seen en face. -Qualifiers:
Bronchial walls are usually not identifiable
radiograph-
ferent
resulting
A radiologic
use of which is not recommended.
Linear opacities properly qualified
with respect to size, location, and Orientation
5 tO be preferred.
trough
filter, n. 1. Radio! phys. Any x-ray filter
traversed
by a longitudinal zone of diminished
thickness.
2. Radio!. An x-ray filter designed to
attenuate
preferentially
those parts ofthe primary
cified.
absorbers
517
GLOSSARY
tramline
shadow,
n, -s [usually
in plural]. Radio!.
Parallel or slightly convergent
linear opacities that
suggest the planar projections of tubular structures and that correspond
in location and oriontation to elements of the brOnchial tree. They are
generally
assumed
to represent thickened bronchial walls. (Such shadows are of possible pathobogic significance
only when they occur outside
the limits of the hilar shadows where bronchial
walls may be seen in the normaL) -Synonyms:
thickened
bronchial
wails,
tubular
shadows
ben, including scatter, emerging from two spoolfled absorbers
in the path of an x-ray beam. 2.
Qualitative: The difference
in attenuation
of diftheir physical densities,
effective
atomic numbars, and path lengths. -Evaluation:
A fundamental concept of radiologic physics.
subse9ment,
n, -s. Anat/Radiol.
A unit of pulmonary tissue that is supplied
by a bronchus of
SOCIETY
shadow, thickened
almost es-
tramline
bronchial wall. -Evaluation:
radiobogic
descriptor, but dearly a
misnomer
to be avoided.
Shadow of a tubular
structure
is acceptable
if the anatornic
significance of a shadow is truly obscure;
otherwise,
thickened
bronchial
wail or Calcified arterial wail
is to be preferred.
turner. n, -s. 1. A swelling or morbid enlargement.
2. Pathol anat/Radio!.
Literally,
a mass. -.Synonym: mass. -Evaluation:
A useful descriptor.
Mass is preferred. The term does not differentiate
between a neoplastic
and a nonneoplastic
mass;
its use as a synonym
for neoplasm
is to be
condemned.
T
V
tension,
adj. 1. The state of being stretched
or
strained.
2. Physiol/Med. A state characterized
by
cardiorespiratory
functional
impairment
caused
by pneumoor hydrothorax.
3. Radio!.
The accumulation
of gas or fluid in a pleural space
in an amount sufficient
to cause compression
of
the ipsilateral lung, markedly enlarge the hernithorax, depress the hemidiaphragm,
and displace
the medistinum
to the opposite
side; applicable
only in the presence
of clinical cardiorespiratory
embarrassment.
-Evaluation:
An inferred conclusion to be used only as specified
in the definition. In fact, tension in relation to pneumothorax
Valsalva
maneuver,
n. Physiol. Forced expiration
against a closed glottis, usually but not necessarily from a position
of total lung capacity. A
maneuver
used to produce
transient
increase
in
intrathoracic
pressure.
vascular
prominence,
n. Radio!. Real or apparent
increase in the caliber and/or number of pubmonary vessels beyond the expected
range, which,
in view of the wide range of normal,
does not
necessarily
imply a pathologic
departure
from
normal.
ynonyms: increased vascularity,
vascular engorgement,
pulmonary
hyperemia,
putmonary
plethora,
pulmonary
pleonemia.
These
terms all represent
inferred conclusions
and are
not, therefore, strictly synonymous
with vascular
prominence. Each is applicable only in specified
circumstances
and each must be used with care.
-Evaluation:
The term vascular prominence is
exists only during the expiratory phase of the
respiratory
cycle, since pleural pressure
on inspiration
is usually
subatmospheric. The word
should not be used in the term tension cyst, which
does not satisfy the criteria cited above.
an acceptable
radiologic
descriptor.
vasoconstrictlon,
n. 1. Physio!. The narrowing of a
muscular
blood vessel by contraction
of its musole layer. 2. Radio!. Local or general reduction
in
the caliber of visible pulmonary
vessels
that is
presumed
to result from decreased
blood flow
produced
by contraction
of muscular
pulmonary
arteries.
-Qualifiers:
hypoxic,
reflex.
-Antonym: vasodilation.
-Evaluation:
In the interprotation of conventional
radiographs,
an inferred
conclusion
appropriately
based on radiographic
signs that are usually reliable. In the interpretation
of angiograms,
an explicit
radiographic
conclusion. The term is not synonymous
with oligernia.
Oligerniais
a sign ofvasoconstriction,
a functional
and potentially reversible
process;
it also applies
to wreversible
vessel narrowing.
as in emphysome.
vasodllatatbon,
n. 1. Physiol. The widening
of the
lumen of a muscular
blood vessel by relaxation
of its muscle layer. 2. Radio!. The local or general
increase in the width ofvisibbe pulmonary
vessels
resulting
from increased
pulmonary
blood flow
-Synonym:
vasodilation.
-Evaluation:
In the
interpretation
of conventional
radiographs,
an inferred conclusion to be expressed
with caution,
since apparent
widening
of pulmonary
vascular
shadows
may. in fact, be due to perivascular
edema, neoplasm,
etc. In the interpretation of
angiograms,
an explicit conclusion.
ventilate,
v. Physiol. I. To circulate air into and out
of any closed space. 2. Specifically,
to introduce
fresh air and expel stale air from the lungs by
physiologic
or mechanical
means. 3. To provide
with a patubous opernng for the circulation
of air.
-Qualifiers:
hyper-; hypo-.
ventilated,
adj. 1. Having had fresh air admitted
and stale air expelled
by physiologic or mechanical means. -Qualifiers:
hyper-; hype-.
ventilation,
n. Physio!/Radio!.
1. The dynamic acts
of inhaling fresh air and exhaling stale air. 2. The
movement
of air into and out of the lungs. 3.
Inspiration
and expiration.
-Qualifiers:
hyper(preferred)
or over- ; hype. (preferred) or under-.
-Synonyms:
breathing. respiration; cf. aeration,
inflation.
4. Physic!. Oxygenation
of the blood,
specifically
in the act ofrespiration.
-Evaluation:
A useful term if properly used. The term always
wnplies a blphasic dynamic process of admission
and expulsion;
hence, cannot be assessed
from
a single static image. Not to be used synonyrnously with aeration and inflation.
x
x-ray quality,
n. Radio! phys. The effective
energy
or spectral distribution
of an x-ray beam. 1. Usually expressed
in terms of half-value
layer (HVL)
in mm of aluminum.
2. Often implied,
but not
explicitly
defined,
by a statement
of the peak
voltage applied to the x-ray tube. -Synonym:
xray beam quality.
-Evaluation:
A fundamental
physical measurement
useful clinically in spool-
lying and comparing
radiographic
systems
and
techniques.
The practice
of expressing x-ray
quality
in terms of beam hardness
is to be
avoided.
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