Radiological features of the Heart

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Radiological features of
the Heart
Dr. Nivin Sharaf MD
LMCC
Objectives
 This lecture will cover the ILO: Delineate the surface,
and radiological anatomy of the heart
 By the end of this lecture we should be able to:
 Recognize the importance of the surface anatomy of
the heart
 Differentiate between PA and AP views of the heart
 Recognize the different anatomical structures viewed in
the AP/ PA and lateral views of the chest
Surface Anatomy
Surface Anatomy Cont.
Important points to remember
 Apex: Left 5th intercostal space, mid clavicular line
 Aortic
 Pulmonary
 Tricuspid
 Mitral
 “AParTment M”
Surface Anatomy Cont.
PA View
 1. Chest radiograph PA projection
 In a PA chest film of diagnostic quality the medial ends
of the clavicles are equidistant from the spinous
process of the adjacent thoracic vertebra. This
indicates that it was taken with a truly sagittal X-ray
beam. The hemidiaphragm should project at the level
of the posterior portion of the tenth rib, or lower. This
indicates that the exposure was made during deep
inspiration.
PA View Cont.
 In adults the heart and major vessels attached to it cast almost all
of the mediastinal soft-tissue density shadow between the two
radiolucent lung fields. (The vertebral column and sternum also
contribute to the mediastinal shadow.) The right border of the
mediastinum is composed of the following set of structures (listed
from superior to inferior):
 brachiocephalic artery and R. brachiocephalic vein superimposed
 superior vena cava and aorta superimposed
 R. atrium
 inferior vena cava
PA View Cont.
 The left border of the mediastinum is composed of the following set of
structures (also listed from superior to inferior):
 L. subclavian artery and L. brachiocephalic vein superimposed
 posterior part of the aortic arch (the aortic knob)
 pulmonary trunk
 auricle of the L. atrium (atrial appendage)
 L. ventricle
 Even though the diaphragm is one continuous sheet of muscle it
radiographs as two distinct hemidiaphragm silhouettes.
Notice the patient is standing!
Positioning
Machine
AP View
Portable X Ray Machine
Lateral View
 In this view the tracheal lumen appears as an almost
vertical radiolucent band which ends just behind the superior
aspect of the posterior border of the cardiac shadow. The
radiodensities of the two hila are superimposed at the
inferior end of the trachea.
 The radiolucent area bounded by the sternum anteriorly and
the cardiac shadow and ascending aorta posteriorly is called
the retrosternal area. The radiolucent area directly posterior
to the lower part of the cardiac shadow is called the
retrocardiac area.
 As in the PA projection, the diaphragm images as two
separate hemidiaphragms in the lateral projection.
References
 http://ect.downstate.edu/courseware/radatlas/Thorax/1chestra.html
 http://www.usfca.edu/fac_staff/ritter/chestxra.htm
 http://www.fmh.org/blank.cfm?print=yes&id=176
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