ER measurements / Ddx/Things mamma didn’t tell you etc…
Please keep in mind the saying: “One of the most dangerous things in
medicine is a radiologist with a ruler” when using this document.
Thanks to everyone who help make this possible!!!
“Ctrl + F” to search this document
Phone numbers
ER: 5705
MRI (1.5T-afterhours, basement): 7408 (3T, neuro/MR building): 3510
CT 64 slice: 8019, GE single slice (no-recons): 6581, PET-CT in nuc med (64
slice):6150, Siemens 16 slice (neuroCT)
Fileroom/Tech room/Core: 5513, 5332
US: 5450
ER Greaseboard: Login through QuestSunrise Acute CarePatient ListStatus
Board
IT helpdesk: 3333
Code: 6123
StatRad: 858-626-8106
Environmental services (make bed): 5491, pager 6842
Loan pager: go to hospital operator room on floor 1 of Douglas Hospital to get pager,
call 1-877-474-3428, say UCIMC, stay on phone until you get test page
Karen Eckl (TalkTech): x6847, pager 7383
Eric Devries (PACS): pager 2869
David Duffey (PACS): pager 8183
VA AGFA problems: 877-777-2432 Joe Calderon: H:951-223-3503 C:408-775-4552
VA PO contrast for inpatients: 5657
VA ER: 3556, 3557, 3558
Contents:
US/inc. ObGyne (non-ultrasound)
Neuro (inc. all spine, head and neck)
Chest/Cardiac
MSK
GI
GU
Nucs
Peds
Other
USinc. ObGyne (non-ultrasound), and some GI
Pregnancy
Always get the BHCG. BHCG > 2000, should see GS (TV), sac size grows about 1mm a
day after 4-5 weeks until about week 9
Please refer to the following images for “pseudosac” sign seen in ectopic, and “double
decidual sign” or “intradecidual sign”universally present when MSD ≥10mm, is one of
the earliest signs of nl pregnancy
http://radiology.rsna.org/content/245/2/385.full
http://radiopaedia.org/articles/double_decidual_sign
Transvaginal
MSD ≥ 8mm = yolk sac
MSD ≥ 16mm = fetal pole = embryo
CRL ≥ 5 mm = heat beat, heart beat may be seen as early as 1.5mm
Transabdominal
MSD ≥ 20mm = YS
MSD ≥ 25mm = fetal pole
Should be able to obtain FHR around 5 weeks
(Bolded criteria above are most reliable and most important)
Fetal heart rate (average nl120-160bpm), but is based on fetal age, measured on M-mode
ultrasound, the lower limit of normal may be 90 bpm at 6 weeks or less, and 110bpm at
greater then 6weeks, from 5 to 9 weeks the heart rate rapidly increases from 110 to 175
bpm then gradually decreased to 160-170bpm. Nl heart beat at 6 weeks is about 90113bpm.
Fetal demise after T1 bradycardia most often occurs within the first week after detection
of the brady; F/U recommended at 1 week; about 25% of T1 bradycardia will go on to
demise
http://radiology.rsna.org/content/236/2/643.full
http://www.jultrasoundmed.org/cgi/content/abstract/14/6/431
Chart of nl fetal heart rates best on GA
http://www.i-am-pregnant.com/encyclopedia/F/Fetal-Heart-Rate/
Minimum FHR based on fetal pole:
2mm embryo: 75 beats per minute
5 mm embryo: 100 beats per minute
10 mm embryo: 120 beats per minute
15 mm embryo: 130 beats per minute
Coulam CB, Britten S, Soenksen DM. Early (34-56 days from last menstrual period)
ultrasonographic measurements in normal pregnancies. Hum Reprod. 1996
Aug;11(8):1771-4.
FYI: Note that nl heart rate for children 1-10yo is 70-120bpm, and HR may be 10bpm
faster in women than men
B-HCGafter 1 month, HCG doubles Q2d, peaks at 10-12w, then decreases to 22w, then
increases again. BHCG 5000embryonic pole, 7000yolk sac, 10,000heart beat
FYI only (not reliable):
Week from the Last Menstrual Period Amount of HCG in mIU/ml
3
5 -50
4
3 - 426
5
19 - 7,340
6
1,080 - 56,500
7-8
7,650 - 229,000
9 - 12
25,700 - 288,000
13 - 16
13,300 - 254,000
17 - 24
4,060 - 165,400
25 - 40
3,640 - 117,000
Because of the wide variation in values, the test is not useful in establishing the gestational age of
a pregnancy.
http://www.obfocus.com/questions/qanda7.htm
If an echogenic intracardiac focus (>90% in LV) is detected on fetal US, there is about a
1% risk for chromosomal abnormality, but this % is somewhat debatable, and most
centers will recommend amniocentesis
Echogenic fetal bowel when the bowel is brighter than the liver and as bright as bone
in T2, worrisome for CF or chromosomal abn/aneuploidy (ex. Down’s)recommend
amnio, T3 echogenic bowel is a common finding and of uncertain significance
<20w GA, cannot reliably dx placenta previa, highest incidence during T2, many partial
previas will resolve, but complete rarely does, overdistended bladder and myometrial
contractions may give false positives, obtain post-void images; note a full bladder may
under-dx cervical incompetence
http://emedicine.medscape.com/article/404639-media
Placental abnormalities (increase w/ C-sx, often seen w/ previa)
Percretia(5%, worst, placenta penetrates entire uterine wall), incretia, accretia(75%)
Pregnancy/Breastfeeding and Contrast
Non-trauma pregnant patients need to sign a consent form for CT. IV iodine and IV
gadolinium effects in humans are not fully understood, both cross the placenta, and
should be avoided if possible. There is concern IV iodinated contrast may suppress
neonatal thyroid function, and some recommend checking thyroid function in neonate in
first week post-partum if iodinated contrast was given during pregnancy. The fetal
thyroid starts trapping iodine by around 10-12w.
http://www.ajronline.org/cgi/content/full/191/1/268
For both iodinated contrast and gadolinium based media in breast-feeding—it is thought
to be generally safe to resume breast feeding right after the study due to the extremely
low absorbed infant dose, but if the patient has any concerns, they may abstain for 24hrs
http://www.acr.org/SecondaryMainMenuCategories/quality_safety/contrast_manual/Full
Manual.aspx#page=65
Most important reference: ACR Contrast Manual (latest as on Oct. 2010 is V7):
http://www.acr.org/SecondaryMainMenuCategories/quality_safety/contrast_manua
l.aspx
Four main recommendations for documentation in the radiology report for both iodinated
and gad-based contrast per this manual in pregnant patients:
1. That information requested from the study cannot be acquired without the use of IV
contrast or by using other imaging modalities.
2. That the information needed affects the care of the patient and fetus during the
pregnancy.
3. That the referring physician is of the opinion that it is not prudent to wait to obtain this
information until after the patient is no longer pregnant.
4. Obtain informed consent from patient if possible
“Blighted ovum” = failed pregnancy
Transcranial ultrasound after stroke for vasospasm: Lindegard ratio: MCA/ICA velocity
Hyperemia 1.7 to 3, vasospasm >3
Nl non-pregnant US uterus(VA chart):
8 x 5 x 4cm
Subchorionic hemorrhage
Most is small, should be followed as is assoc. w/ high risk fetal loss, but is usually
insignificant when small
Important to ddx placental cotyleydons, chorionic plate indentations, myometrial
contractions and venous lakes vs placental abruption which presents as an area of
decreased placental enhancement “True placental abruptions were characterized by large,
contiguous, and retroplacental and/or full-thickness areas of low enhancement that form
acute angles with myometrium”. Especially look for this in trauma patients.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2716448/
Endometrium (VA Chart):
Premenopausal
Immediate postmenstrual 1-4mm
Proliferative 4-8mm
Secretory 8-14mm
Postmenopausal
Asymptomatic nl ≤ 8mm
w/ hemorrhage nl ≤ 4mm
w/ Tamoxifen and HRT stripe can be ≤ 8mm normally, but depends on type of HRT
Ovary
A dominant follicle in an ovulating woman is normally <3cm
Suggestive of malignancyNodular soft tissue component, septal wall thickening,
RI<0.4, pulsatility index <1
Asymptomatic ovarian cysts SRU 2009 Guidelines
http://radiology.rsna.org/content/256/3/943.full
Simple Unilocular cysts (inc. paraovarian, and cysts w/ a single <3mm septation or
small wall calcification)
In women of reproductive age:
≤3 cm: Normal physiologic findings; at the discretion of the interpreting physician
whether or not to describe them in the imaging report; do not need follow-up.
>3 and ≤5 cm: Should be described in the imaging report with a statement that they are
almost certainly benign; do not need follow-up.
>5 and ≤7 cm: Should be described in the imaging report with a statement that they are
almost certainly benign; yearly follow-up with US recommended.
>7 cm: Since these may be difficult to assess completely with US, further imaging with
magnetic resonance (MR) or surgical evaluation should be considered.
In postmenopausal women:
≤1 cm: Are clinically inconsequential; at the discretion of the interpreting physician
whether or not to describe them in the imaging report; do not need follow-up.
>1 and ≤7 cm: Should be described in the imaging report with statement that they are
almost certainly benign; yearly follow-up, at least initially, with US recommended.
Some practices may opt to increase the lower size threshold for follow-up from 1 cm to
as high as 3 cm. One may opt to continue follow-up annually or to decrease the frequency
of follow-up once stability or decrease in size has been confirmed. Cysts in the larger end
of this range should still generally be followed on a regular basis.
>7 cm: Since these may be difficult to assess completely with US, further imaging with
MR or surgical evaluation should be considered.
Hemorrhagic cysts (normally resolve in 8w):
In women of reproductive age:
1. Cysts ≤3 cm: At the discretion of the interpreting physician whether or not to describe
them in the imaging report; do not need follow-up.
2. Cysts >3 and ≤5 cm: Should be described in the imaging report; do not need follow-up.
3. Cysts >5 cm: Should be described in the imaging report; short-interval follow-up (6–
12 weeks) with US recommended to ensure resolution. While imaging in the follicular
phase, on days 3–10 of the menstrual cycle, is optimal, the panel recognized that this is
sometimes difficult to coordinate in clinical practice.
Early post-menopausal (may still ovulate)
Any hemorrhagic cyst early short-interval (6-12w follow-up)
Late post-menopausal
Any hemorrhagic cystsurgical exploration
Ovary volume = 0.523 x width x length x thickness, normal average volume = 10mL
If one ovary is 1.75 times larger than the other, think ovarian torsion, also look for
peripheral follicles
Stein-Leventhal (PCOD)—classic findings--numerous small (<1cm) peripheral cortical
follicles (at least 5 in each ovary) w/ hyperechoic ovarian stroma, prominent fibrous
capsule, both ovaries are enlarged
Spleen size ≤ 13cm
Common bile duct= measured at porta hepatis, 6mm max up to age 60, then add 1mm
for each decade thereafter for upper limit of normal (ex. 7mm at 70yo) Brant and Helms
Carotid Doppler for carotid artery stenosis
Nl Doppler angle 40-60 degrees
VA chart 2003
To detect slow flow:
Decrease the PRF, use low wall filter, decrease Doppler angle, increase sampling area,
lower frequency transducer
Renal Doppler/Renal artery stenosis
RI less than 0.8, elevated > 0.9
Main renal artery less than 200cm/sec, some say 150cm/s
Nl RAR <3.5, if >, then stenosis may be >60%
In RAS may see spectral broadening w/ or w/o flow reversal, absent diastolic flow may
indicate stenosis >50%
RI is not elevated is RAS, more commonly obstruction, ATN, etc… May be elevated in
chronic RAS with CRI
Liver length on ultrasound is measured saggittal R10length of the right lobe (VA),
should be ≤ 15.5cm
Caudate lobe is between IVC and portal vein on sagg ultrasound
Left hepatic vein is seen on sagg US of left lobe
90% hemangiomas are hyperechoic w/o halo, most of the rest (“atypical hemangioma”)
are hypo with hyper rim
Gallbladder
Fasting for at least 6hrs is recommended before exam, often can’t fast in ER cases
Two major criteria: gallstones and sonographic Murphy’s
Gallbladder wall thickness should be ≤ 3mm
Common bile duct measured at porta hepatis should be ≤6mm up to 60yo, and thereafter
increase by 1mm per decade (For example, upper limit of normal, in a 70yo is 7mm).
Brant and Helms
Main pancreatic duct ≤3mm
Kidneys (L>R) (VA chart)
Female:9.5-12cm
Male: 10-12.5cm
Pyloric Stenosis (CHLA measurements)
Recent literature suggests an “olive” is palpable less than 50% of the time, and maybe
this is generous (before reported as 80%)
Baby is fed glucose water, and imaged w/ US. If pylorus is not seen due to overdistended
antrum, place NGT
Normal pylorus opens Q15min
Post-operative pylorus is difficult to eval.
Normal values
Muscle wall thickness ≤3.5mm
Pyloric channel length ≤16mm
Pylorospasm: Muscle wall thickness or pyloric length measurements may overlap those
accepted as positive for hypertrophic pyloric stenosis, to differentiate, image over a long
period of time
Journal of Ultrasound in Medicine, Vol 17, Issue 11 705-711, 1998
If there is suspicion for pyloric stenosis and the measurement values are at the upper
limits of normal and close follow-up is usually recommended (us. w/in a few days)
Germinal matrix/intraventricular hemorrhage in neonates
I - subependymal and/or GM (less than 10% vent. volume), seen in caudothalamic groove
II- intraventricular, less than 50% vent. volume (normal sized vent), overall good prog.
III - IV, w/ > 50% of vent. volume (vent enlarged), 20% mortality
IV-(some say this is now better termed hemorrhagic venous infarction, is Grade III w/
extent into cerebral hemispheres, 90% mortality
Upper limits of normal abdominal/limb vasculature (VA chart)
Abdominal aorta: 3cm
Common iliac artery: 2cm
Femoral artery:1.5cm
Popliteal artery:1.0cm
TIPS malfunction (VA chart)
Peak shunt velocity <60cm/s or >200cm/s
Change in peak shunt velocity >50cm/s
MPV velocity <30cm/s
Renal transplant rejection
Donor ureter usually implanted to superolateral wall of bladder, donor renal vessels us.
anastomosted to native iliac vessels
Hypertrophy and increased C/M differentiation are normal findings, Dilatation confined
to the renal pelvis/mild hydronephrosis may not be clinically significant, but should be
followed and an etiology should be sought
Lymphocoeles at 4-8 weeks after Sx, in 15% of Txs
Urine Leak/urinoma often presents w/in 3w at UVJ, no septations unless infected
Normal main renal artery velocity < 200cm/s
Arteries have low resistance w/ brisk upstroke and nl RI from 0.6 to 0.8
ATN occurs in some extent in all cadaveric Txs, most common need for dialysis 2 weeks
post transplant, non-specific imaging, may have increased RI
Acute rejection-occurs in up to 40% in first few weeks
Chronic rejection-occurs after 3 mos, most common cause of late graft loss
Obstruction is rare, but when it occurs it is likely due to ischemic fibrosis at UVJ
Renal artery thrombosis, very rare, seen in first month, most common from acute
rejection w/ retrograde thrombosis, no renal flow on US
Renal artery stenosis-most common vascular complication in up to 10% in first year,
may be segmental w/ chronic rejection, PSV >200cm/s w/ turbulence, parvus tardus
distally
Venous thrombosis-acute pain, renal swelling, oliguria in first week, absent venous flow
and reversal of flow in the renal artery
Renal vein stenosis-spectral Doppler w/ 3-4X increased velocity across a select region
indicates a hemodynamically significant stenosis
http://www.learningradiology.com/lectures/facultylectures/usrenaltransplantppt_files/fra
me.htm
Hepatic transplant rejection
Rejection in 50-70% of patients at some point after Tx
Nl in first few days post-op: rapid upward systolic stroke but no diastolic flow
Acute rejection-often nl imaging, may be heterogenous or decreased liver echotexture
Conversion of hepatic vein waveform from triphasic to monophasic (not specific), but
concerning
Chronic rejection-increased periportal echogenicity
Biliary complications as well as vascular thrombosis/stenosis-most w/in 3 months
Often biliary strictures are at the anastomotic site
HA thrombosis (#1 vascular comp.)—no flow at porta hepatic, hypoechoic blotchy
infarcts seen at liver edges, may cause biliary ischemic strictures, the bile ducts in a Tx’d
liver depend solely on HA blood, impending thrombosis may be seen with absence of
diastolic flow, then dampened diastolic peak, then total loss of waveform
HA stenosis-at anastomotic site-flow w/ spectral broadening/turbulence, distal tardus
parvus, flow ≥ 2m/s at anastomosis (abn), look for pseudoaneurysm at anast. site
Nl waveforms in right and left hepatic arteries = patent proper HA
Biloma most common at anastomotic site. Biloma may also be caused by HA thrombosis.
Portal Vein/IVC thrombosis/stenosis-rare, focal narrowing at anastomosis is nl
Clinical sonography, a practical guide, Sanders et. al. 2006
http://radiographics.rsna.org/content/23/5/1093.full.pdf
Nl portal vein diameter 8-12mm
Portal vein thrombosis cavernous transformation
Normal hepatic duct diameter3-6mm (some say 4mm is ULN), right and left hepatic
ducts should be ≤2mm
DVT
The veins should be compressible to 2mm or less (each vein wall counts for 1mm), tech
must perform compression if able, be careful w/ augmentation maneuvers in patients w/ a
known DVT
Normal testis measures about 5x3cm
Thyroid
Nl each lobe: 4x2x2 cm
Isthmus: 4-6mm
10-40% of adult population has thyroid nodules
Increased size of thyroid lesion does not correlate w/ increasing prob. of malignancy
4-33% of thyroid CA undergoes cystic degeneration
Ultrasound may detect 2-3mm lesions
Most often benign: eggshell calcification and a thin echolucent halo
Features suggestive of malignancy: solid, hypoechoic, irregular margins, fine punctuate
calcifications (papillary), note that although cancer is hypoechoic in >70% of cases, a
hypoechoic nodule is statistically more likely to be benign
A cold nodule with hypervascular periphery and hypovascular center suggests benignity
except in Hashimoto’s thyroiditis, when a cold nodule is internally hypervascular, the
chance of malignancy increases
Only about 4% of thyroid cancers are hot
85% of thyroid nodules are cold, and 85% of cold nodules are benign
Papillary carcinoma is more often less vascular than normal thyroid tissue
Mets can be diffuse or focal. Focal mets often go to the lower pole and appear as solid
hypoechoic well-defined non-calcified nodule, most cancer presents as a solid nodule
Caution should be taken as to not rely on ultrasound features alone for malignancy
http://emedicine.medscape.com/article/385301-imaging
Pediatric hip
Alpha angle normally >60o
Graf Ultrasound Classification of Acetabula:
Type I
Normal acetabular morphology. Alpha angle greater than 60 degrees.
Type II a Child less than three months of age with borderline acetabular
morphology and nondisplaced femoral head.
Alpha angle is 50 to 60 degrees, consistent with immature acetabulum.
Vast majority of these children progress to normal by three months of age
(96%).
Repeat scanning at three months of age may be done to confirm this
expected progression to normal.
Type II b Same as II a, but child is greater than three months of age. These children
need intervention, since by three months, immature acetabulum should no
longer be present.
Type II c Acetabulum is deficient with nondisplaced femoral head (becomes II d
when decentering femoral head is present).
Type III
Type IV
Alpha angle is less than 49 degrees. Intervention is required regardless of
age.
Acetabulum is deficient.
Alpha angle is less than 49 degrees with subluxation of femoral head.
Intervention is required regardless of age.
Dislocated hip. Intervention warranted.
A. The normal anatomy visualized on a pediatric hip ultrasound should include the
following:
1. Cartilaginous femoral head.
2. Bony acetabulum.
3. Ilium, ischium, and pubic bones
4. Labrum.
5. Femoral head ossification centers if child is older.
B. The abnormal anatomy visualized on a pediatric hip ultrasound could include the
following:
1. Subluxation or dislocation of the femoral head.
2. Abnormal alpha angle.
3. Abnormal thickness of labrum.
4. Presence of pulvinar.
5. Asymmetry of the ossification centers.
http://uvmrads.org/protocols/31-ultrasound/29-pediatric-hip-ultrasound-protocol-ddh
Vesicoureteral Reflux VUR





Grade I – reflux into non-dilated ureter
Grade II – reflux into the renal pelvis and calyces without dilatation
Grade III – mild/moderate dilatation of the ureter, renal pelvis and calyces with
minimal blunting of the fornices
Grade IV – dilation of the renal pelvis and calyces with moderate ureteral
tortuosity
Grade V – gross dilatation of the ureter, pelvis and calyces; ureteral tortuosity;
loss of papillary impressions
The younger the age of the patient and the lower the grade at presentation the higher
the chance of spontaneous resolution. Most (approx. 85%) of grade I & II cases of
VUR will resolve spontaneously. Approximately 50% of grade III cases and a lower
percentage of higher grades will also resolve spontaneously
http://en.wikipedia.org/wiki/Vesicoureteral_reflux,
http://radiographics.rsna.org/content/20/1/155/F10.expansion.html (pictures)
Neuro (inc. all spine, head and neck)
(inc. all spine, head and neck)
UCI MRI acute stroke technique:
Most common (LASH/non-LASH, MRA head, MRA neck): the head and MRA head are
done without contrast. Axial images are termed “the partitions.” Then a bolus of gad is
given and the MRA neck is done. Then the 3D reconstructions with gadolinium are made.
From the neck images, the MRA head 3D reconstructions are made, and added back to
the MRA head study. So the second set of MRA head images are with gadolinium and
reconstructed from the MRA of the neck. Please note if MR perfusion (uses gad) for
stroke is to be performed, you cannot do MRA of the neck with gad, and you cannot do a
contrast brain MRI (if the ordering clinician is on a “seek and destroy” mission, and not
necessarily looking for stroke). You can do the MRA neck without gad, but it is often
very noisy. However, I have seen a few turn out very well.
>6 hrs ischemia bright on FLAIR
Enhancement with high T2 in stroke pt suggests infarction less than 2w old
Some NIR believe that if the stroke is not yet bright on FLAIR the brain is salvageable
and not yet infarcted
Predental space 3mm adult, 5 mm child
Note normal pseudosubluxation of the cervical spine in a child (C2/C3 (40% of children),
less at C3/4)—anterior displacement of C2 on C3 of ≤4mm, occurs in flexion only,
reduces in extension
http://www.wheelessonline.com/ortho/pseudosubluxation_of_the_c_spine
http://www.orthobullets.com/spine/2048/pseudosubluxation-of-the-cervical-spine
Prevertebral soft tissue normal values (get inspiratory extension views-unless severe
trauma)
≤ 3mm at C3, be concerned if ≥ 5mm
Adult: ≤ 7mm at C2, and ≤ 22mm at C6
Child: ≤ 14mm at C6
Note SCIWORA in a child (us. less than 8yo) (abn. not seen on plain films or CT)
SCIWORA is due to the ligamentous flexibility and elasticity of the immature spine,
greatest in C-spine, often will not present w/ deficit (maybe just initial tingling) until
48hrs later, get MRI
http://www.wheelessonline.com/ortho/sciwora_syndrome_spinal_cord_injury_w_o_radio
logic_abnormality
Best temporal bone anatomy (I found e-anatomy to not be that great):
http://headneckbrainspine.com (images a bit grainy)
http://www.radsmd.com/coronalCTatlas3.htm (slow)
Transtentorial herniation (3 types):
Uncal-dilated pupil, duret, ips hemip, later eye down and out, C/L homo hemianop
Central-suprasellar cistern
Upward cerebellar-quadrigeminal cistern, us. from cerebellar mass/edema
Flexion injury Narrowed disc space above involved vertebral body
“Basal cisterns” (4)
-suprasellar
-paramesencephalic
-ambient
-prepontine
Epiglottis
Imaging may be false negative early in disease
Obtain an extension radiograph w/ mouth closed
Adult, normal thickness 3-5mm, >7mm is 100% sens/spec for epiglottitis, aryepiglottic
fold > 4.5mm suspicious
For all age patients highly specific and sensitive for epiglottitis:
Epiglottic width/C3 vertebral body width > 0.5
Epiglottic width/epiglottic height > 0.6
Radiologic diagnosis of epiglottitis: Objective criteria for all ages. Rothrock et al. Ann
Emerg Med. Sept.1990
Lateral radiograph of the neck demonstrates and enlarged epiglottis (red arrow) and
thickening of the aryepiglottic folds (yellow arrow). There is also reversal of the normal
lordotic curve in the cervical spine and slight dilatation of the hypopharynx.
From learningradiology.com
There is no completely reliable approach to the injured cervical spine
http://www.ajnr.org/cgi/content/full/28/9/1819
Atlantooccipital dissociation (more common in children) --avoid C-spine flexion-Atlanto occipital condyle distance should be less than 5mm (some say 4mm or less)
regardless of age
Wackenheim’s Clival Line (picture below)
The odontoid should be tangential to or below the line that extends along the dorsal
clivus
Harris Method
Line along the posterior C2 body should be less than 12mm from basion and the basion to
the tip of the dens should be less than 12mm (this is the BDI, basion to dens interval)
http://w3.cns.org/university/pediatrics/Spinks_chapter_figures73108_Page_07.jpg
Powers Ratio
BC/OA
If >1, then anterior subluxation, Ratio<0.55 is posterior translation
http://www.wheelessonline.com/ortho/atlantooccipital_disassociation
http://4.bp.blogspot.com/_zmXoIvqjSJw/TFb1TkM1SII/AAAAAAAAAKM/20bxSBgC
S10/s400/%E5%9C%96%E7%89%871.jpg
ICA dissection is most common in the cervical portion, 2cm from bifurcation (35-50yo)
In intracranial ICA dissection, most patients are less than 30yo
PAC-man/crescent sign—best seen on axial T1W The dark part is flow, bright part is the
dissection intramural hematoma
http://radiographics.rsna.org/content/28/6/1711/F29.expansion
http://radiographics.rsna.org/content/28/6/1711.full
Spinal enhancement
Fibrosis in the spine enhances. A recurrent disc does not, unless it is imaged late. There
may be enhancement around a synovial cyst (us. at facet) and type I Modic changes
Spinal infection sparing the disc space = TB
Disc space biggest at L4/5
Lines for determining basilar invagination
Chamberlain’s (line from posterior hard palate to posterior lip of foramen magnum,
abnormal if dens >3mm above line)
http://www.raddaily.com/data/articles/neuro/skullchamberlain.jpg
MacGregors (easier to use, line from posterior hard palate to base of occiput, abnormal if
dens is >4.5mm above line)
http://www.raddaily.com/whitepaperarticle.php?articleTitle=Lines+of+the+Skull+Base
Pathologic spinal fracture—pathologic(met) vs non-path Paravertebral soft-tissue
masses and infiltration of posterior elements are the most reliable signs of a malignant
fracture. Pathologic fractures show more homogeneous replacement of the bone marrow.
“Fluid sign” rarely occurs in metastatic fractures, in addition intravertebral air w/in the
compressed vertebrae is more often associated with avascular necrosis benign
compression, osteolytic mets (low T1, high T2) blastic (low T1, low T2).
“Pseudocapsule” may be seen post-gap w/ spinal met
http://radiology.rsna.org/content/225/3/730.full
Bright on SWI phase images = iron/blood, dark=calcium, this is only good for small
lesions and is unreliable in the basal ganglia. Also look for clot, on SWI phase or MAG
images particularly in the Sylvian fissure.
Make sure to check the coronal images for any extra-axial bleed in trauma patients.
Best sequences for cord lesion: axial GRE and sagittal PD
Measure neural foramina in L-spine on saggittal and C-spine on axial. Use GRE and/or
T2. Note GRE artifacts often cause measurements to be incorrect.
Subdural hematoma W/L: 90/40 or 90/50
Internal capsule blood supply
Largest supply-> MCA M1 lenticulostriate (LTS)
Anterior--LTS, recurrent Huebner off ACA (inf. half)
Genu--LTS
Posterior--LTS, ant choroidal off ICA (inf. half)
Cerebellar tonsils > 5mm below the foramen magnum (ectopic tonsils) and/or
pointedChiari I
Sella turcica
AP Length of 17mm
Depth 13mm
Width 15mm
Investigate if depth exceeds length
Cranial arteries/Circle of Willis segments—some segments are variable and there is
disagreement on the number of segments for certain arteries
ICA (4, some give up to 7)
http://www.meddean.luc.edu/lumen/MedEd/neuro/neurovasc/navigation/iccerv.htm
C1-cervical
C2-petrous
C3-cavernous
C4-supraclinoid (gives rise to ophthalmic a., pcomm, ant. Choroidal
MCA (3 or 4) (MCA is not part of COW)
M1-horizontal (sphenoidal)
M2-insular (Sylvian)
M3-opercular
M4-cortical (terminal)
Some sources state there is no M4, and then the M3 is termed the “cortical” segment
(M2/M3 segment more commonly bifurcates than trifurcates into main trunks (middle
trunk not always present)
ACA (5)
A1-from ICA to AComm
A2-from Acomm to bifurcation into pericallosal and callosamarginal, or to junction of
rostrum and genu of CC, ascending
A3-pericallosal (may anastomose w/ PCA), ascending, extends around genu until sharp
posterior turn
A4- horizontal, above CC, A4 and A5 separated by plane of coronal fissure
A5- horizontal, above CC
Practical neuroangiography. Pearse Morris, 2007.
(Pericallosal)
http://www.meddean.luc.edu/lumen/MedEd/neuro/neurovasc/navigation/peri.htm
Callosomarginal often branches off of pericollasal
(8=pericallosal, 9= callosomarginal)
http://www.mdconsult.com/das/book/body/222994964-2/0/1611/59.html
Best seen on a coronal view-the paired pericallosal arteries are midline, and give rise to
the callosomarginals which deviate laterally then run anteriorly and are more dorsal than
the pericallosal
Recurrent a. of Huebner is variable in origin, most commonly off proximal A2, lateral A
Comm or distal A1 segment
PCA (3 or 4)
P1-from basilar tip to PComm (part of COW)
P2- courses laterally around midbrain to junction w/ post. choroidal a.
P3-runs through lateral quadrigeminal cistern and divides into P4
P4-cortical branches
P1 and P2 strokes cause infarcts in thalamus and midbrain. P3 and P4 cause cortical
strokes (some sources say there is no P4, just P3)
Some call P4 “cortical branches”
Vertebral artery (4)
V1-take off of subclavian to transverse foramen at C5 or C6
V2- from foramen transversarum of C5 or C6 to C2
V3- from C2 foramen transversarum, loops around posterior arch of C1, passes between
atlas and occiput
V4-intracranial segment from where is enters the dura to basilar a.
Vertebral artery most commonly dissects at C1/C2 region (Segment 3), us. in young
healthy individuals following minor trauma or spontaneous
Most common neurological symptoms correlate w/ Wallenberg (lateral medullary
syndrome), also HA, nuchal pain etc…
Watershed infarct—most commoncortical border zone infarcts) between ACA and
MCA, also MCA and PCA, less common“internal watershed” involves corona
radiate/centrum semiovale (poorer prognosis)
Us. from severe unilateral carotid stenosis, prolonged hypotension (bilateral), or carotid
dissection (unilateral), aortic dissection (bilateral)
http://www.radiologyassistant.nl/en/484b8328cb6b2
Internal Watershed—us. bilateral from hypotension, sometimes looks like “rosary/string
of pearls” configuration
http://radiopaedia.org/cases/iwi01
http://jnnp.bmj.com/content/78/8/907/F1.large.jpg
http://missinglink.ucsf.edu/lm/ids_104_cns_injury/response%20_to_injury/Watershed.ht
m
Chronic watershed ACA/MCA and MCA/PCA
http://www.mdconsult.com/das/article/body/2229908052/jorg=journal&source=&sp=21537242&sid=0/N/672988/1.html#f08001175005
Usually unilateral watershed is from severe carotid stenosis
Flexion/extension plain film: Translation greater than 3mm in either flex or ext =
considered unstable
Cavernoma,= cavernous hemangioma, popcorn, dark ring
Blood stages on MRI (T1/T2)
Hyperacute --hours oxyHgb (low/high)
Acute --days deoxy (low/low) w edema
Subacute early --days4-7 IC metHgb (high/low)
Subacute late --weeks EC metHgb (high/high)
Chronic--years hemosiderin (low/low) slit, or greater than 2 weeks
Blood is not bright on T1 until after one week
Modic
T1 T2
I
low high (edema)
II high high (fat)
III low low (sclerosis)
Klippel-Feil Syndrome (3 things)-short neck, low dorsal hairline, restricted neck
mobility from segmentation anomaly w/ synostosis of cervical vertebrae often w/ block
cervical vertebrae, decreased number cervical vertebrae. Often w/ other congenital
anomalies and Sprengel’s deformity of scapula. K-F deformity only involves C-spine abn.
#1parotid tumor is benign mixed/pleomorphic adenoma, #1 malignant is mucoepidermoid
#1 submandibular is Warthin tumor
Normal pressure hydrocephalus is a clinical diagnosis, may see narrow convexity
sulci, transependymal edema, dilatation of temporal horns/atria/ventricles out of
proportion to atrophy, T2 aqueductal flow void “flow void sign/hyperdynamic/pulsatile
flow” = dark signal on T2 in the aqueduct
http://emedicine.medscape.com/article/342827-imaging
http://radiopaedia.org/articles/normal-pressure-hydrocephalus
Hydrocephalus look for bowing/dilatation of the recesses of the third ventricle
DVA was formerly “venous angioma”, see DVA look for associated cavernomathis is
what causes problems (bleeds etc.)
Sinovertebral nerve—cause of pain from annular tear
Conus ends at L1/2 us. by 3 months of age
Axial midbrain: Cerebral peduncles antcollici post to thisquad plate cistern post to
this
All holoprosencephaly have absent septum pellucidum
TB of spine affects body>disc
Spinal stenosisAP diameter cervical spine <12mm, <11.5 mm lumbar—these mm are
debatable, a canal <10mm is usually considered stenosis. Some say AP diameter 1115mm=relative stenosis, less than 10mm on saggittal absolute stenosis
ALL rupturesag MRI, look at anterior disc annulus, and for STS
“Mastoid antrum” is largest mastoid air cell
Aditus ad antrum is from the epitympanic recess or attic to the mastoid antrum
Branchial cleft cyst, type 2 is most common
Pharyngeal tonsils = adenoids, most
superiorhttp://en.academic.ru/pictures/enwiki/71/Gray994-adenoid.png
Palatine tonsil at level of uvula
http://www.aafp.org/afp/2002/0101/p93.html
BVORVOG + ISS = SS
SOV is medial to superior rectus
Dermoid/epidermoid most common congenital orbital lesion
Holoprosencephaly(cortical mantle, no thalamic cleavage = fused thalami) vs
hydrancephaly(no cortex) vs severe hydro (interhemispheric fissure)
Toxo= diffuse parenchymal calcs
Chest/Cardiac
Pneumothorax increases with expiratory views
Traumatic pseudoaneurysm vs normal ductus bump
Ductus bump is smooth and convex w/o acute margins, both at isthmus region
Aortic Dissection
Stanford Type A = ascending only
Stanford Type B = descending only
DeBakey Type I = ascending + descending
DeBakey Type II = ascending only
DeBakey Type IIIa = descending only
DeBakey Type IIIb = descending, including abdominal
***Asc. Requires surgical repair, asc. only is 60% of total
Thoracic Aortic Aneurysm
Recommendations, elective repair of asc aorta ≥ 5.5cm and desc at ≥6.5cm, and possibly
at smaller size if other comorbidity (bicuspid valve, Marfan’s etc..). Generally, for both
asc. and desc. ≥4cm = aneurysm
The main pulmonary artery diameter should be <3cm on CT. Pulmonary artery
diameter ≥ 3.5cm,95% chance of pulmonary HTN, mean pulmonary artery pressure for
HTN is around 20mmHg
Right lung segments (10 bronchopulmonary segments)
A PALM Seed Makes Another Little Palm
UPPER LOBE
o
o
o
apical
posterior
anterior
MIDDLE LOBE
o
o
lateral
medial
LOWER LOBE
o
o
o
o
o
superior
medial basal
anterior basal
lateral basal
posterior basal
Left lung segments remember, the lingual is part of the left upper lobe (us. 8
bronchopulmonary segments-somewhat debated)
ASIA ALPS (upper/lower)
UPPER LOBE
o
o
o
o
apical posterior
anterior
superior lingular
inferior lingular
LOWER LOBE
o
o
o
o
superior
posterior basal
lateral basal
anterior medial basal
Lung collapse LOBAR COLLAPSE
Right-->
Upper—superior medially, Golden S
Middle--over right heart border, triangle on lateral
Lower--over right hemiD, posterior triangle over posterior sulcus on lateral
Left-->
Upper--anteriorly, luftschikle, may look like UL haziness, look for volume loss
(lingulamedially/heart border, ant. triangle above oblique fissure):
Lower--medial posterior behind heart, posterior triangle over posterior sulcus on lateral
http://emedicine.medscape.com/article/353833-imaging (pics)
http://www.radiology.co.uk/srs-x/tutors/collapse/left.htm
Centrilobular pattern often spares the lung periphery
Stages of sarcoid
Chest films in sarcoidosis have been classified into four stages:
1.
2.
3.
4.
Bilateral hilar lymphadenopathy
Bilateral hilar lymphadenopathy + pulmonary disease
Only pulmonary disease
Irreversible fibrosis
1-2-3- lymph node sign, small nodules along fissures (specific), small perilymphatic
nodules in mid and upper lung
Persistent peripheral lung consolidationCOP/BOOP, eosinophilic pneumonia
BOOP is COP when there is no known cause
UIP—fatal, progressive, extensive fibrosis, IPF accounts for more than 60% of cases,
UIP is IPF when there us no known cause
Hypersensitivity pneumonitis
Mosaic pattern, spares lung bases, centrilobular nodules
http://www.radiologyassistant.nl/en/46b480a6e4bdc
Upper lobes
Cystic fibrosis
EG
Ankylosing spondylitis
Allergic alveolitis/chronic extrinsic alveolitis
Sarcoid
Berylliosis
Granulomatous disease (post-primary TB), histoplasmosis, sarcoid
granulomas/micronodules
Radiation Rx (dep. on site)
Pneumoconiosis
PMF
Lower Lobes
Mets
LAM
Scleroderma
RA
Dermatomyositis
Lymphangitic spread
Asbestosis
IPF
Tuberculosis
Primary TB: Initial infection with consolidation, adenopathy and pleural effusion.
Secondary TB: Post-primary or reactivation TB.
This is the reactivation of the original infection.
Usually located in the apical segments of upper lobes with cavitation
Endobronchial spread: May occur in both primary and secondary TB, when the
infection is not contained.
Hematogenous spread (miliary TB): May occur in both primary and secondary TB,
when the infection is not contained.
http://www.radiologyassistant.nl/en/46b480a6e4bdc
Miliary pattern--cocci, tb, thyroid mets
Radiation pneumonitis seen 4-12w post therapy
Radiation fibrosis after 6-12months post-therapy, stabilizes at 2yrs
http://radiographics.rsna.org/content/20/1/83.full
Post-pneumonectomy lung
First 24hrs after sxair only
Fills with fluid at rate of 2 rib spaces/day
Hemithorax is 80-90% filled w/ fluid at end of 2w
Should be completely opacified at around 4mo
Maximum shift toward pneumonectomy side at 6-8mo, return to midline of previously
shifted mediastinum is highly sensitive for late complication
Air w/ in resection cavity after prior opacification suggests bronchopleural fistula
(drop in fluid level by >2cm) or infection
From learningradiology.com
The right paratracheal stripe should be less than 4mm. If enlarged is most often due to
regional adenopathy.
#1 aortic arch anomaly is nl left arch w aberrant right subclavian
#1 right aortic arch anomaly is right arch with aberrant left subclavian, both can cause
dysphagia
Fleischner criteria for pulmonary nodules
Good to remember-->less than 4mmonly high risk for primary needs a FU at 12mo
Fleischner Criteria
Nodule Size
(mm)
Low risk patients
High risk patients
Less than or
equal to 4
No follow-up needed.
Follow-up at 12 months. If no
change, no further imaging
needed.
>4 - 6
Follow-up at 12 months. If no change,
no further imaging needed.
Initial follow-up CT at 6 -12
months and then at 18 - 24 months
if no change.
>6 - 8
Initial follow-up CT at 6 -12 months and
then at 18 - 24 months if no change.
Initial follow-up CT at 3 - 6
months and then at 9 -12 and 24
months if no change.
>8
Follow-up CTs at around 3, 9, and 24
months. Dynamic contrast enhanced CT,
PET, and/or biopsy
Same at for low risk patients
Note.—Newly detected indeterminate nodule in persons 35 years of age or older.
Low risk patients: Minimal or absent history of smoking and of other known risk factor.
High risk patients: History of smoking or of other known risk factors.
Information taken from www.radswiki.net
Emphysema
Centrilobular (#1)-proximal bronchioles, upper zones, smoking
Panlobar-lower zones, @1AT exac by smoking
Paraseptal-adjacent to pleural surface and fissures, smoking, subpleural blebs
Giant cell looks similar to Takayasu
Polyarteritis nodosa and aneurysms of renal a's
Reverse bat wing: COP, chronic eosinophilic PNA, vasculitis, aspiration, contusion,
infarction
MSK
Transcapular view is the “Y view”
“Rim sign”-seen in posterior shoulder dislocation, distance from anterior glenoid to
medial border of humeral head >6mm
Normal AC joint 3-8mm with smooth continguous border inferiorly (<5mm vertical
step-off), widening usually from FOOSH
Normal coracoclavicular distance 11-13mm
Acromioclavicular Joint Separation Grades
Type
Anatomy
Radiographic findings
Prognosis
Stretching of AC
ligament
I
AC joint is stable
Only seen on stress views of
injured and uninjured
shoulders=widening of AC
joint
No instability
Widening of AC joint but a
normal coracoclavicular
distance
May require
arthroplasty
Sprain
CC ligament intact
Partial or complete
rupture of AC ligament
II
Subluxation
III
IV
Posterior
V
Inferior
Partial, but not
complete, disruption of
CC ligament
Stress films may still be
required to demonstrate
widening of both AC joint
and CC space
Disruption of both AC
and CC ligaments
Widening of both the AC and
CC spaces on routine erect
film
AC and CC ligaments
disrupted but
coracoacromial
ligament remains intact
Distal end of clavicle lies
inferior and posterior to
acromion seen best on
axillary view
AC and CC ligaments
disrupted
Coracoacromial
ligament remains intact
Sternoclavicular
separation occurs as
well
Marked widening of both the
AC and CC space
Sternoclavicular dislocation
Internal fixation
VI
Distal end of clavicle
displaced inferiorly and
lodges in biceps and
coracobrachialis
m.muscles
Distal end of clavicle comes
to lie inferior to acromion
This is chart is from learningradiology.com
Normal scapholunate interval is less than or equal to 2mm, >2mm-suspicious, if ≥
4mm, most would call scapholunate dissociation
Physis closed-giant cell, chondroblastoma
Fibrous dysphasia “ground glass” with bowing/other deformity
Erosive osteoarthritis- gull wing, osteopenia
Always say chondrmyxoid fibroma w/ NOF
ACL runs lateral to medial
Exostosis--rule of 10's
PVNS--> knee, hip, elbow, ankle
The sustentaculum tali is a projection off the calcaneus
Foot fractures often missed:
Anterior process of calcaneous and cuboid
Myositis ossificans hot on bone scan, zonal phenomenon w/ peripheral rim calcification
to help ddx from malignancy
Malignant ST tumor--MFH/fibrosarc (#1), then liposarc
JRAcarpal erosions, capitate the most
MRI knee
Look at saggittal PD and T2 are best for ligament and meninscal tears
Medial knee-tibia is like a golf tee, lateral tibia is like a hockey stick
Posterior meniscus should be bigger than anterior portion
Tear should extent to articular surface
Magic angle = when a structure is oriented 55 degrees to main magnetic field, T2 times
increase 100X (increase bright signal artifact mainly seen in inf. patellar tendon and
rotator cuff, ankle)
Hip columns
Most common injury is isolated posterior column
Least common is isolated anterior column
Line a–a1 establishes anterior (AC) and posterior (PC) columns. Anterior (AW) and
posterior (PW) walls lie lateral to line b–b1
http://www.ajronline.org/cgi/content/full/182/6/1367
Calcaneal fracture
Bohler’s angle is normally greater than 20 degrees, and less than 20 suspect calcaneal
fracture
http://www.joint-pain-expert.net/images/calcaneus_fracture2.jpg
Salter Harris (SALTR = slipped, above, lower, through, raised)
I- epiphyseal separation, physeal widening, ex. SCIFE
II- metaphyseal + epiphyseal, most common SH fracture
III – physis and epiphysis, ex. Tillaux, intra-articular
IV – epiphysis, physis, metaphysic, intra-articular
V – epiphysis crushed, us. NOT detected acutely
AVN stages (2 diff’t classifications):
Ficat femoral head AVN Stages
Stage
Clinical Features
Early
0 Preclinical
0
I Preradiographic
+
II Precollapse
+
Transition:
Radiographs
0
0
Diffuse Porosis, Sclerosis, Cysts
Flattening, Crescent Sign
III Collapse
IV Osteoarthritis
++
+++
Broken Contour of Head Certain
Sequestrum, Joint Space Normal
Flattened Contour Decreased Joint Space
Collapse of Head
Enneking Osteonecrosis stages
Stage
I
II
III
IV
V
VI
Pain
None
None
Occasional
Limp
Continuous
Severe
Radiographs
Slight increased density
Reactive rim
Crescent sign
Step off flattening
Collapse
Deformed
Calcaneus is epiphyseal equivalent, intraosseus lipoma or unicameral bone cyst (common
at metaphysis)
Patella is largest sesamoid
Pes anserinus (anteromedial proximal tibia)
“Say Grace before SupTer”
(Sartorius, gracilus, semitendinosis)
Hand w sublaxation distally, think SLE or Jacoud (post RF)
Hair on end skull-Thalessemia
Cotton wool skull with thickening of iliopectineal line (ant column) is Pagets
Chronic villonodular synovitis is giant cell tumor of tendon sheath
Hemophilia-cystic changes on both sides of joint
Malignant ST tumor--retroperitoneal, large, heterog T2 signal
Fibrous histiocytoma is second most common ST tumor after lipoma
T score < -2.5 = osteoporosis
>2cm=NOF, <2cm fibrous cortical defect
Morton neuroma darkT1 and T2, enhances brightly
Hardware lucency = 2mm or more
Adamantinoms/osseous fibrous dysplasia
Hemophiliac arthropathy, sclerotic joint sn w no osteopenia, pseudotumor of hemophilia
You do not need gadolinium for MRI in osteomyelitis
Nidus (lucent area w/ surrounding reactive sclerosis)osteoid osteoma, osteoblastoma,
LCH(EG), osteomyelitis (inc.Brodie’s)
Fallen fragment unicameral bone cyst with pathological fracture, may be confused
w/ sequestrum
Sequestrum osteomyelitis (inc.Brodie’s) LCH (EG), metastases, radiation necrosis,
fibrosarcoma, or FILE (Fibrosarcoma, Infection, Lymphoma, EG), may mimic osteoid
osteoma, “button” in skull w/ difft differential
Fluid/fluid level ABC, telangiectatic osteosarcoma, giant cell, chondroblastoma,
fractured simple bone cyst, myositis ossificans, synovial sarcoma, mets (renal/lung)
The following link offers a very good list of MSK differentials:
http://home.caregroup.harvard.edu/departments/radiology/residency/teaching/differential/MSKDD
x.doc
GI
Appendicitis
Normal appendix in adult diameter ≤6mm, wall ≤3mm
Look for inflamed adjacent fat, fluid, appendecolith
Portal venous gas/air vs pnemobiliapneumobilia is normally > 2cm central from liver
capsule, portal venous gas is usually more fine, linear, branching, may extend to liver
capsule
Liver Segments (8, 4a/b)
http://www.radiologyassistant.nl/en/4375bb8dc241d
ABDOMINAL TRAUMA INJURY GRADING SCALE ( from AAST)-inc. kidneys
Spleen (either/or)—SPLENIC TRAUMA GRADING SCALE-Grade 1
-subcapsular hematoma <10% of surface area
-capsular tear <1cm deep
Grade 2
-Subcapsular hematoma 10-50% SA
-intraparenchymal hematoma <5cm diameter
-laceration 1-3 cm deep, not involving vessels
Grade 3
-Subcapsular hematoma >50% SA or expanding and ruptured
-subcapsular or parenchymal hematoma
-Intraparenchymal hematoma >5cm or expanding
-Laceration >3cm deep, or involving vessels
Grade 4
-involves hilar vessels with devascularization >25% of spleen
Grade 5
-shattered hilar vascular injury
Liver---HEPATIC TRAUMA GRADING SCALE
Grade 1 (either/or)
-Subcapsular hematoma (SH) <1cm
-Liver Laceration (LL) <1cm deep
Grade 2
-SH or LL 1-3 cm
Grade 3
-SH or LL >3cm
Grade 4
-LL or SH >10cm Lobar destruction devascularization
Grade 5
-Global destruction or devascularization
Grade 6
-Hepatic avulsion
Pancreas---PANCREATIC TRAUMA GRADING SCALE
Grade 1 (either/or)
-Minor contusion/hematoma w/o ductal injury
-Superficial laceration w/o ductal injury
Grade 2 (either/or)
-Major contusion/hematoma w/o ductal injury or tissue loss
-Major laceration w/o ductal injury or tissue loss
Grade 3
-Laceration w/ distal transection or parenchymal injury w/ ductal injury
Grade 4
-Proximal (to right of the SMV) transection or parenchymal injury, not involving the
ampulla
Grade 5
-Massive disruption of the pancreatic head
-Advance one grade for multiple injuries up to Grade III
Kidney (either/or)---RENAL TRAUMA GRADING SCALE
Grade 1
-Hematuria with normal imaging studies
-Contusions
-Nonexpanding subcapsular hematomas
Grade 2
-Nonexpanding perinephric hematomas confined to the retroperitoneum
-Superficial cortical lacerations less than 1 cm in depth without collecting system injury
Grade 3
-Renal lacerations greater than 1 cm in depth that do not involve the collecting system
Grade 4
-Renal lacerations extending through the kidney into the collecting system
-Injuries involving the main renal artery or vein with contained hemorrhage
-Segmental infarctions without associated lacerations
-Expanding subcapsular hematomas compressing the kidney
Grade 5
-Shattered or devascularized kidney
-Ureteropelvic avulsions
-Complete laceration or thrombus of the main renal artery or vein
http://radiographics.rsna.org/content/21/suppl_1/S201.figures-only
In the groin region, the iliac vein is medial to the artery
Upper limits of normal for adult lymph node stations (short axis)-non-thoracic
specific
Short gastric 6mm
Retrocrural 6mm
Retrocaval 6mm
Paracardiac 8mm
Mediastinal 10mm
Gastrohepatic ligament 8mm
Upper paraoartic 9mm
Portocaval 8-10mm
Portahepatic 7mm
Lower paraaortic 11mm
Axillary, neck, groin 15mm
Please note that there is some discrepancy regarding these measurements, but the more
important is to note which stations have the lower cut-offs (retrocrural, etc..)
Malignant nodes may appear more round as opposed to oval and have loss of the normal
fatty hilum
Check out RECIST v1.1
http://radiology.ucsd.edu/radres/Education/journal_club/RECIST%201_1%20nodes.pdf
http://radiology.rsna.org/content/180/2/319.full.pdf+html
Duodenal ulcers>%w/ H. pylori, anterior and superolateral duodenal bulb
Gastric ulcerslesser curvature/antrum, benign ulcers us. on posterior wall
Distal left posterior wall of esophagusmost common location for Boerhaave
syndrome
Gastrografin (not used in babies/children) often given for esophageal perforation
suspicion due to rapid absorption, however if it gets in lungs causes necrotizing
pneumonia due to high osmolarity (barium can cause fibrosis), if Gastrografin study is
negative but suspicion remains a barium swallow is then indicated, if barium gets into
peritoneal cavity may cause peritonitis/granulomatous rxn , that is why Gastrografin is
used in cases of suspect bowel perforation
Fatty Liver CT
HU difference of less than 18 between liver and spleen equals fatty liver w IV contrast
Normal liver 50-75 HU non con
Liver HU on non-con less than 40 mod/severe hepatic steatosis
Large caudate
PBC, PSC, Budd-Chiari, caudate is generally large in cirrhosis
Ciliated hepatic foregut cyst--bright on T1, segment 4 only, <3cm
Epithelial hemangioepthelioma
Retroperitoneal fibrosis-autoimmune
Sprue increase risk of SB lymphoma
Tuberus sclerosis lymphangioma
Infarction of bowl--lack of enhancement
Carcinoid- TI, rectum
Type 1 choledochal cyst, most common, ALL are at risk of developing cholangioCA
Type III = choledochocoele
Ameboema right colon
BsC cholangitis and cancer
PSC mild IHBD dilatation
Santorini seal for symptomatic panc divisum
Normal alpha fetal protein (AFP) level is <10mg/ml. 40% w/ liver cancer have normal
AFP
GU
Adrenal adenoma, fast washout, greater than 50% at 10 min
Size > 4cm usually cancer, also can do MR chemical shift
#1cause of adrenal hemorrhage is septicemia, w/ AH, insufficiency is rare
Urethral Injury
Anterior urethra=bulbar and penile,
Posterior = Memb-UG, P
DIAGNOSED BY RGU
Type 1- puboprostatic ligament rupture, prostate and bladder apex displaced superiorly,
post urethra stretched/intact,
Type 2-above UGD in prostatic segment, contrast in extraperitoeneal pelvis
Type 3-membranous disrupted, most common type, tear extends down through the
UGD, may include proximal bulbous, contrast in extraperitoeneal pelvis and
perineum (contrast extrav us. at or above AND below UGD)
Type 4-bladder neck injury extending to the anterior urethra
Type 4A- bladder base injury with periurethral extravasation
Type 5-Pure anterior urethral
*CT does not allow distinction between Type II and III injuries, but may be suggestive
drawing from http://myradnotes.wordpress.com/category/trauma/
Bulbous urethra is from external sphincter to penoscrotal junction
Extraperitoneal bladder injury is most common
Beware that sometimes extraperitoneal can look like intraperitoneal and sometimes there
is a component of both (intra req. sx repair)
Bladder injury
Type 1- contusion (pt may have hematuria, but nl CT)
Type 2- intraperitoneal rupture, sx emergency, direct blow to distended bladder ruptures
dome
Type 3- interstitial bladder injury, serosa intact, no extrav
Type 4- Extraperitoneal rupture (80-90%); more common w/ pelvic fxs, rupture is us. due
to laceration by bone fx frag, contrast into perivesicle space so called “molar tooth
appearance”
4A-simple
4B-complex
Type 5- Combined bladder injury
http://radiographics.rsna.org/content/20/5/1373.full
Prostate
Nl dimension (StatDx)
3cm craniocaudal
4cm wide
2cm AP
More precise = volume = 0.523 x length x width x thickness (1cc prostate tissue = 1g)
Normal is about 20g in young man, enlargement is >40g StatDx
Prostate CA is us.T2 low signal//hypoehoic in peripheral posterior prostate, but not
always
Prostate Specific Antigen
There is no specific normal or abnormal PSA level, and there is no optimal level
recommended for biopsy. It is nonspecific and may be elevated in BPH, UTI’s,
prostatitis, etc.. However, the higher the PSA or if there is high velocity (increase by
>0.75ng/ml in one year), or a low percent free PSA (<10%), the more likely the chance of
cancer. Historically, 4ng/ml has been the upper limits of normal for PSA, but a lower
cutoff (2.5ng/ml) should be used in younger patients. From published reports: normal
prostate on exam + PSA <4 = 15% chance of cancer, PSA from 4-10 = 25% chance, and
PSA >10 = 67%. Many believe that in prostate cancer patients with a PSA <10, there is
less likelihood of capsular penetration or skeletal metastases
http://www.webmd.com/prostate-cancer/guide/psa
http://radiology.rsna.org/content/243/1/28.full
Some use age-specifc PSA cut-offs:
Age 40-50: 0-2.5 ng/ml
Age 50-60: 0-3.5
Age 60-70: 0-4.5
Age 70-80: 0-6.5
Most common seminal vesicle lesion is a cyst
Bosniak
1-simple, water density
2-thin septa, fine wall calc, <3cm, 18% chance of CA
2F- min enh of thin septa, min septal thickening, modular calc, totally intrarenal <3cm
high density non-enh well-marginated
3- thickened irregular wall/septal enh, 33%
4-enhancing ST component, 92%
A renal/ureteral stone/calculus >4mm is more unlikely to pass on its own. 90% of stones
4mm or less will pass on their own.
The normal urinary bladder wall is ≤3mm when the bladder is well-distended
The nl testis is 5 by 3 cm
Nuclear Medicine
HIDA
Conjugated Bili should be less than 4 mg/dL, may give more radiopharm if jaundiced
Patient should have fasted for at least 4hrs and less than 24hrs. If patient fasted <4hr or
>24hr may not see GB
Fasting >12 (or some say > 24hrs) and no GB seen, can give CCK
Once radiotracer is seen in the bowel, morphine (0.04mg/kg/IV)can be given to aid in
GB visualization
Not seeing the GB on HIDA at 60 min-#1 cause= acute chole, other causes: improper
fasting as above, acute acalculous chole, chronic chole, hepatic insuff.,
hyperalimentation, alcoholism, pancreatitis, hyperbilirubinemia, opioid abuse
Nl study:
Clear blood pool:15min
EH bile ducts at:10-15min
SB: 30-60min
GB: <1hr
Acute chole- non-visualization of the GB by 60 min. when bowel is seen
Acalculous chole (10%) High M &M, failure to visualize GB, along w/ low EF (<35%)
post-CCK
Low EF post-CCK, high PPV for chronic acalculous chole, persistent GB activity w/o
washout, us. see GB if wait long enough
Chronic acalc> acute acalc
Acute-Non-vis of GB at 1hr w/ vis of SB, morphine mat help in dx by decreasing false +
Chronic alcalculous cholecystitis-GB EF <40%, high PPV
Please note that HIDA cannot reliably distinguish calculous vs. acalculous and
correlation is needed w/ ultrasound or CT
Note sphincter of Oddi spasm/dysfunction
Rim sign: complicated/gangrenous chole
DDx’ing neonatal hepatitis vs biliary atresia-> may want to pre-treat with phenobarbital
(5mg/kg/24h PO for 5 days prior to study)
V/Q
Perfusion imaging may be done first, and if no abnormalities are seen, the ventilation
portion may be cancelled in some instances (ex. pregnancy)
Modified PIOPED Criteria




HIGH PROBABILITY SCAN ≥80% chance of PE
o 2 or more large mismatched segmental defects or equivalent
moderate/large defects with a normal x-ray
o Any perfusion defect substantially larger than radiographic abnormality
INTERMEDIATE PROBABILITY SCAN 20-79%
o Multiple perfusion defects with associated radiographic opacities
o Greater than 25% of a segment and less than 2 mismatched segmental
perfusion defects with
 Normal radiograph.
 One moderate segmental
 One large or two moderate segmental
 One large and one moderate segmental
 Three moderate segmental
o Difficult to characterize as high probability or low probability
LOW PROBABILITY SCAN <20%
o Nonsegmental defects-small effusion blunting costophrenic angle,
cardiomegaly, elevated diaphragm, ectatic aorta
o Any perfusion defect with substantially larger radiographic abnormality
o Matched ventilation and perfusion defects with normal chest radiograph
o Small subsegmental perfusion defects
NORMAL
o No perfusion defects
*"Segmental Equivalent" Sizing: The moderate segmental defect is counted as 0.5 of a
large segmental defect (two moderate sized segmental defects are therefore equivalent to
one large segmental defect). All moderate and large defects can be than added up to result
in total segmental equivalent units. (Example: 3 moderate segmental defects and 1 large =
2.5 segmental equivalents)
*Note a solitary triple match in the mid or upper lung zone has a very low likelihood,
while one in the lower lobe is intermediate
*“Stripe sign” –very low probability
*Pleural effusion w/ no other defect-very low probability
*One moderate mismatch w/ no CXR abn. may be placed in high group if patient has
cancer (controversial)
Excellent resource:
http://www.svhrad.com/DigLib/Pulmonary/Lung%20Scan/Interpretation%20of%20VQ%
20Scans%20for%20PE.htm
GI bleed
Most commonly use tagged RBC (other choice is SC—faster, but a little less sensitive)
No patient prep
Image 1min/frame for 1-2hrs
False + = free tech, varices/hemangioma on blood pool, penile/uterine blush
False - = low bleeding rate, venous bleed, tech. failure, cessation of bleed
Nuclear cardiac stress test (VA)
Stress images are over rest
http://tomography.files.wordpress.com/2007/10/unlabelledmedyaleedu.gif
Look at perfusion defects, wall motion, EDV, EF and raw data for artifacts (motion, gut)
due to filtered backprojection
Most commonly use sestamibi (have to use high stress dose/low rest dose) or thallium
(more radiation, but different energies that don’t overlap with Tc-99, (so don’t need the
high/low)
Nl LVEDV is us. less than 120mL, but based on height/weight, Nl EF is about 50-75%
Transient ischemic dilatation (TID), seen in stress images in patient’s with 3-vessel
disease
Ga> Indium for discitis
Indium WBC don't see kidney, see bones. Octreotide see kidneys
Peds—for more complete info please see the Cleveland Clinic training
modules https://www.cchs.net/pediatricradiology/
Congenital heart disease (CHLA)
Left atrial enlargement-mitral stenosis >regurg
Width of main PA should equal supraaortic tracheal width
Sinus venosus asd, papvc, vein must be redirected to left atrium
ASD increased pulmonary vascularity, most close by 2-3mos
VSD most common shunt defect assoc with syndromes and trisomies
AV canal = endocardial cushion defect, in complete there is primum ASD, inlet VSD and
common AV valve
VSDs and hyperinflation
PDAs increase size of LA and LV
LA enlargement in VSD not ASD
VSD in first few weeks, ASD in childhood or adolescence
Coarctation more common in adults, short segment juxtaductal type
Bicuspid aortic v in 85% of coarcts, often w poststenotic dilatation of asc aorta
Intercostals #1-3 from thyrocervical trunk from the carotids
HLHS has PDA and ASD and 75% w coarctation, does not present for a few days (3-5),
right heart is dilated, Norwood (first stage is BT shunt-right subclavian artery to right
PA), Glenn shunt (cavopulmonary), Fontan (fenestration between IVC and RA-later
closed
Round pna --> S. Pneumonia
Neuroblastoma calcs, but no fat, Wilms can have fat, Nb more often goes to bones, from
adrenal, ages 2-4
Wilma goes to lungs, renal vein to right atrium, Beyond 10 yrs old wilms=RCC
NEC seen after 72hrs
Submucosal->bubbly pneumatosis, subserosal->linear
Blount’smedial depression of tibia
Duodenal hematoma is child abuse
Hutch diverticulum needs repair
PIE = barotrauma, first 2-3day in neonate with ARDS
Lymphangiomatosis/asia goes to bone/lung
Chylothorax
Big heart first few days = Ebsteins , tricuspid atresia
Newborn kidney upper limit is 4cm
MCDK look for UPJ obst on other side
Discoid miniscus easily tears, seen in child
Hepatoblastoma (tumor thrombus in kids is Wilma or hepatoblastoma) vs
hemangioendothelioma (vascular)
Permeative bone lesionEwing, LCH, lymphoma, osteosarcoma
Peribronchial cuffing interstitial edema
Surfactant deficiency/ARDS is babies less than 36 weeks and less than 2.5 kg
TTN peaks at 24hrs higher w/ c-section or precipitous vag delivery, clears from periphery
to center and top to bottom, treatment is CPAP
Intussusceptions between 6 mo and 2 yrs, small bowel intussusception is surgical only
Meconium aspiration, air block phenomenonPTX
Ileal duplication is #1 duplication cyst
Resect esophageal duplication due to ectopic gastric mucosa and higher risk of cancer
Only tubular duplication cysts communicate with lumen
Intralobar sequestration is 75%, venous drainage is through pulmonary system to LA,
m=f, diagnosed after 20 yrs, hemoptysis, pneumonia
Extralobar left CPA, males, can present as an adrenal mass, most symptomatic in first 6
months, 60% have other congenital anomalies
Most sequestration ix excised to decrease infection rate
Normal thymic echotexture=liver
Valves and coronary arteries go with ventricles in transposition
Other
Outpatient contrast reaction prophylaxis (2 main protocols)
ONE
1. Prednisone 50mg PO at 13hr, 7hr, and 1hr before exam plus
2. Diphenhydramine (Benadryl) 50mg IV, IM, or PO 1 hr before exam
-ORTWO
1. Methylprednisolone (Medrol) 32mg PO at 12hr and 1hr before exam plus
2. Diphenhydramine (Benadryl) 50mg IV, IM, or PO 1 hr before exam
Emergency Premedication
IV steroids are NOT EFFECTIVE when administered less than 6hrs before exam
Chose ONE of the following 3 protocols. Listed in order of decreasing desirability
1. Methylprednisolone sodium succinate (Solu-Medrol) 40mg OR hydrocortisone
sodium succinate (Solu-Cortef) 200mg IVq4h until contrast study required plus
diphenhydramine 50 mg IV 1hr prior to contrast injection*** most desired protocol
2. Dexamethasone sodium sulfate (Decadron) 7.5 mg or betamethasone 6.0 mg IV q4h
until contrast study must be done in patent with known allergy to methylprednisolone,
aspirin, or non-steroidal anti-inflammatory drugs, especially if asthmatic. Also
diphenhydramine 50 mg IV 1 hour prior to contrast injection.
3. Omit steroids entirely and give diphenhydramine 50 mg IV.
http://www.acr.org/SecondaryMainMenuCategories/quality_safety/contrast_manual/Full
Manual.aspx#page=9
Contrast extravasation
Inflammatory response may not peak until 1-2d after extravasation
Be careful in patients with atherosclerotic disease and children
Monitor extravasation in dorsum of hand or feet even more carefully
Always monitor for compartment syndrome (#1), and skin ulceration
Raise limb to level of heart and may use cold or warm compressNote that these have
not been associated w/ any type of more rapid recovery
Keep patient in radiology dept. until you are satisfied, no further reaction with occur
If severe reaction, ER or emergent surgical consult
http://www.acr.org/SecondaryMainMenuCategories/quality_safety/contrast_manual/Full
Manual.aspx#page=17
PD long TR short TE
MRI gad stays in system for 7hrs
Frequency:readout:chemical shift
The following is an excellent chart developed by Dr. Wu at the VA for the order of
optimal imaging modalities for endocrine tumor/disorders