Examination 2
case 01
(a) Ligamentum teres. This strong ligament inserts into the fovea centralis of the
femoral head along with important nutrient vessels.
(b) Acetabular labrum. This incomplete fibrocartilaginous ring contributes to hip
joint stability. It may undergo traumatic or degenerative tearing leading to hip pain,
instability and mechanical symptoms such as clicking.
(c) Gluteus medius tendon. This is an important abductor and lateral rotator of the
hip that inserts upon the lateral and posterior facets of the greater trochanter.
(d) Iliotibial band (ITB) or tract. This long dense fascial band is a continuation of the
tensor fascia lata muscle. It may undergo friction with resultant thickening and
inflammation as it passes over the greater trochanter, producing painful, proximal
ITB friction syndrome.
(e) Transverse part of the ilio-femoral ligament. The ilio-femoral ligament is a
thickening of the joint capsule and is the strongest of the three hip ligaments, the
other two being the ischio-femoral and pubo-femoral ligaments.
case 02
(a) Right sacroiliac joint.
(b) Right anterior inferior iliac spine.
(c) Right superior pubic ramus.
(d) Left obturator foramen.
(e) Contrast in bladder.
Cystograms are performed by either hand injecting, or running in a contrast infusion
through either a urethral or suprapubic catheter. Both antero-posterior (AP) and
lateral views should be taken, and the bladder should be filled as much as a patient
can tolerate.
Bladder rupture can be either intraperitoneal or extraperitoneal. Extraperitoneal
ruptures occur with fractures of the pelvis, due to the rigid fixture of the bladder neck.
Intraperitoneal ruptures tend to occur in blunt trauma when the bladder is full. The
tear is usually at the junction of the loose and fixed peritoneum at the posterior part of
the bladder. Intraperitoneal ruptures are treated surgically, extraperitoneal ruptures
are usually managed conservatively. If there is trauma, both retrograde and antegrade
imaging should be performed to ensure that no ureteric trauma has occurred.
case 03
anterior fontanelle
(a) Fourth ventricle.
(b) Cerebellum.
(c) Choroid plexus.
(d) Cingulate gyrus.
(e) Corpus callosum.
The sagittal midline ultrasound of the neonatal brain allows assessment of the midline
structures of the brain that are frequently affected by congenital anomalies.
The choroid plexus should be smooth in outline, uniformly echogenic and
should not extend anterior to the caudo-thalamic groove. The caudo-thalamic
groove is a useful landmark adjacent to the lateral ventricle where the caudate
lobe and the thalamus abut each other. It is important to identify this because any
echogenic structure anterior to this even if it is apparently continuous with the
choroid plexus represents haemorrhage within the ventricle. An oblique sagittal
scan angled through the lateral ventricle along the choroid plexus will demonstrate
the caudo-thalamic groove, which can also be demonstrated scanning in the
coronal plane.
case 04
(a) Right upper lobe bronchus.
(b) Bronchus intermedius.
(c) Left main bronchus.
(d) Left lower lobe bronchus.
(e) Left T11 pedicle.
Bronchograms are performed in an intubated but spontaneously breathing patient to
assess the patency of the large respiratory airways throughout the respiratory cycle.
In cases of bronchomalacia the airway will collapse during expiration resulting in
airtrapping.
External compression of the airways or displacement related to congenital cardiac
and large vessels anomalies can also be apparent.
The trachea splits into the right and left main bronchi at the carina forming a ridge
between the openings of the bronchi. The right main bronchus has a shorter and more
vertical course than the left; it also has a larger calibre. The right main bronchus then
splits into the right upper lobe bronchus and the bronchus intermedius. The right
upper lobe is divided into three segments, the apical, posterior and anterior. The
bronchus intermedius divides into the short right middle lobe bronchus that supplies
the two segments of the right middle lobe: the lateral and medial segments. The right
lower lobe bronchus has five segmental branches: the apical, medial, anterior, lateral
and posterior segments. The left main bronchus has a horizontal and long course. It
divides into the left upper lobe and left lower lobe bronchi. The upper lobe bronchus
supplies five segments: the apical, posterior, anterior and the two lingular segments,
the superior and inferior. The left lower lobe bronchus supplies the apical, medial,
anterior, lateral and posterior segments.
There are several common large airway congenital anomalies, the commonest being
the pig bronchus with the right upper lobe bronchus arising directly from the trachea.
They are rarely of clinical relevance unless cardiothoracic surgery is required. The pig
bronchus can result in a persistently collapsed right upper lobe of the lung when
the patient is intubated. This is because the tip of the endotracheal tube can be distal to
the origin of the upper lobe bronchus and so can occlude it despite the tip of the
endotracheal tube being in an apparent satisfactory position on plain radiographs.
case 05
the base of the penis
(a) Urinary bladder.
(b) Corpus cavernosum.
(c) Corpus spongiosum.
(d) Left testis. Normal testis is high signal on T2 MRI and intermediate on T1. The
epididymis is isointense or hypointense relative to testis on T1 and hypointense on T2-
weighted images.
(e) Left pubic bone.
There are paired dorsal corpora cavernosa, and a single ventral corpus spongiosum,
which surrounds the penile urethra. These can be seen easily on MRI or
ultrasound.
Arterial supply to the penis is from the internal pudendal arteries. Paired cavernosal
arteries run in the corpora cavernosa. Paired deep dorsal arteries lie external to the
tunica albuginea and run laterally to the deep dorsal vein, supplying skin and glans
penis.
Penile carcinoma, although relatively uncommon, can be well visualized on MRI
using T2 and post-contrast T1 sequences. Primary tumours are usually solitary,
ill-defined lesions that are of low signal relative to the corpora on both T1- and
T2-weighted images. Tumours enhance following contrast, but to a lesser degree than
the corpora cavernosa.
case 06
(a) Post cricoid venous plexus.
(b) First rib.
(c) Clavicle.
(d) Left lamina of C5.
(e) Trachea.
case 07
(a) Haustra. The muscularis propria is condensed into three narrow longitudinal
bands, the taeniae coli. The taeniae shorten the colon and act as anchorage for the
circular muscle. This effect causes the haustral pattern seen on barium enema.
(b) Sigmoid colon. This is entirely surrounded by peritoneum and thus has a posterior
mesentery named the sigmoid mesocolon. This allows it considerable freedom of
movement within the lower abdomen.
(c) Valves of Houston, or transverse folds of rectum, are formed by fusion of taeniae
and support the weight of faecal matter, preventing a constant defaecation urge. They
are typically less than 5 mm thick.
(d) Appendix. Its relationship to the caecum is variable. It is retrocaecal in 15% and
longer than 9 cm in 25% of individuals.
(e) Splenic flexure. This is the junction between superior and inferior mesenteric
arteries at the splenic flexure seen in 80% of individuals. This is the most commonly
affected segment in ischaemic colitis since this region is a watershed region between
the vascular territories of the inferior and superior mesenteric arteries.
case 08
(a) Common extensor origin. This is made up of the common origin of the extensor
digitorum communis, extensor carpi ulnaris and extensor carpi radialis brevis
tendons. Tendinopathy and partial tearing of this structure is seen with chronic
microtrauma (overuse) in a condition referred to as ‘tennis elbow’.
(b) Olecranon process. This is the olecranon recess, which is occupied by the olecranon
process when the elbow is extended. It is a common location for intra-articular
bodies which may result in a block to extension.
(c) Medial epicondyle. This bony prominence of the humerus bears the attachment of
the common flexor origin. The ulnar nerve courses over its posterior surface within
the ulnar tunnel.
(d) Ulnar (or medial) collateral ligament (UCL). This is an important ligament complex,
composed of three bundles that act to stabilize the elbow joint and resist valgus
stress. Tears of the UCL are associated with throwing sports such as cricket and
baseball.
(e) Radial head. This articulates with the capitellum. Fractures of the radial head and
neck are common following falls onto the outstretched arm.
case 09
(a) Liver segment 2.
(b) Liver segment 3. The commonest classification used was first proposed by Couinaud
in 1957. This partitions the liver into segments divided by the left and right branch
of the portal vein and the three hepatic veins. The caudate lobe is named as segment 1.
(c) Common hepatic artery, arises from the coeliac artery into the lesser omentum
ascending in front of the portal vein.
(d) Left gastric artery. This arises from the coeliac artery and passes upwards and left
to reach the oesophagus. It ascends along the lesser curve of the stomach, supplying
the lower third of the oesophagus and upper part of stomach.
(e) Superior mesenteric artery. This arises below the coeliac artery and descends over
the uncinate process of the pancreas. It enters the root of the mesentery supplying the
small intestine.
case 10
(a) Left ventricle.
(b) Aortic root.
(c) Right coronary artery (RCA). The RCA arises from the right coronary cusp
(anterior sinus of Valsalva) and runs in the right atrio-ventricular (AV) groove. The
proximal segment gives rise to a conal branch supplying the right ventricular outflow
tract and a sino-atrial (SA) branch supplying the SA node in about 65% of individuals.
The mid segment gives rise to an acute marginal branch supplying the right ventricle
wall. The distal RCA continues in the right AV groove where a branch supplies the
AV node, before continuing to the inferior surface of the heart.
(d) Posterior descending artery (PDA). In a right dominant system, the RCA supplies
the PDA running in the inferior interventricular groove but in a small number
individuals it is a branch of the left circumflex artery.
(e) Posterior left ventricle wall branch. This artery is a continuation of the RCA.
case 11
(a) Right renal pelvis.
(b) Right upper pole pyramid.
(c) L5 right transverse process.
(d) Left ureter.
(e) Left duplex kidney. This is also known as ureteric duplication, which occurs when
there are two pelvicalyceal collecting systems draining one kidney. It is present in
about 1% of the population and is the most common renal anomaly. If the two ureters
fuse prior to entering the bladder it is called a partial duplication and is largely an
incidental finding.
If the two ureters drain independently into the bladder then this becomes a complete
duplication. There is an increased incidence of urinary tract infections and vesicoureteric
reflux in the latter cases.
Intravenous urography has been replaced by CT urography (CTU) in many centres,
but was previously an important investigation in urinary tract imaging. Contrast was
injected intravenously and a series of images taken to look at function and anatomyof the
renal tract. The ureters may not be completely seen due to peristalsis, and prone views
can aid filling.
Remember to look at the remainder of the image for other abnormalities, including
bone lesions, bowel gas pattern and any lesions seen at the lung bases.
case 12
(a) Coeliac axis. This artery arises from the anterior of the aorta at a level between the
T12 and L1 vertebral bodies. In 65–75% of individuals it divides into the left gastric
artery, splenic and common hepatic arteries, 1–2 cm from its origin.
(b) Gastroduodenal artery. This artery lies immediately behind the first part of the
duodenum and therefore ulcers in the posterior wall of the duodenal bulb can result
in life-threatening haemorrhage. The first line treatment for this remains endoscopy
although embolization with interventional radiology using coils or gelfoam provides
a valuable alternative strategy.
(c) Superior pancreatico-duodenal artery.
(d) Right hepatic artery. The common hepatic artery arises from the coeliac axis in
75% of the population. Other common variants to be aware of include an aberrant
origin of the right hepatic artery from the superior mesenteric artery (SMA) (replaced
right hepatic artery in 10–12% of the population) and a replaced left hepatic artery (off
the left gastric artery) in 11–12% of the population.
The blood supply to the liver is divided, with 75% supplied by the portal vein and
25% by the hepatic artery. Interestingly, however, any primary or secondary tumours
in the liver invariably have an arterial supply.
(e) Right ureter.
During angiography of the gastrointestinal tract the bladder often fills with contrast
and it is therefore customary and advisable to cannulate the inferior mesenteric artery
first, so that views of the sigmoid colon are not obscured by an opacified bladder.
case 13
(a) Right anterior cerebral artery.
(b) Rightmiddle cerebral artery.Thelargest branches of the internal carotid artery (ICA)are
the middle cerebral arteries, which supply the majority of the brain including the sensory
andmotor cortices of the head and upper limb, as well as Broca's expressive speech area.
(c) Right posterior cerebral artery.
(d) Left lentiform nucleus (part of the basal ganglia). This is a triangular area of grey
matter between the internal and external capsules. Infarcts aremost frequently seen in the
basal gangliawhich are supplied by the lenticulostriate branches fromthemiddle cerebral
artery and the resultant infarcts are called lacunar infarcts (lacuna¼pond or lake. Latin).
(e) Left frontal lobe.
The vascular territories are significant if there are recent or acute infarcts inmore than one
territory, which imply embolic disease rather than occlusive stenosis within the carotid.
Between the vascular territories lie watershed zones where transient global hypoperfusion
(cardiac arrest, general anaesthesia, systemic shock) can result in impaired
flow to one or both parent vessels thereby compromising circulation to a critical level
in these border zones.
case 14
(a) Right first costo-transverse joint.
(b) Coracoid process of right scapula.
(c) Spine of right scapula.
(d) Tubercle of left third rib.
(e) Companion shadow of right clavicle. The companion shadow is formed by the
skin and subcutaneous tissue that lies superficial to the clavicle. As the x-ray beam
tangentially hits the interface between the skin and the air in the supraclavicular fossa,
it produces the so-called companion shadow.
case 15
(a) Right common carotid artery.
(b) Left subclavian artery.
(c) Oesophagus.
(d) Trachea.
(e) Aberrant right subclavian artery (ARSCA). In approximately 0.5–1% of individuals
the right subclavian artery arises from the aortic arch distal to the origin of the left
subclavian artery. It courses posterior to the oesophagus as it crosses obliquely to the
right side. When the origin is aneurysmal (Kommerell diverticulum) it may cause
dysphagia (dysphagia lusoria).
Note: in patients with a normal right subclavian artery position the brachiocephalic
trunk (BCT) usually has a larger diameter than both the left common
carotid and left subclavian arteries. This is because it carries arterial blood to
the right common carotid and right subclavian arteries. However, in the case of
an ARSCA, the artery to the right of the left common carotid artery is the right
common carotid artery. This has a diameter equal to the other great vessels,
unlike the BCT.
An ARSCA will cause posterior indentation of the barium column in the oesophagus
during a barium swallow.
case 16
(a) Superior cerebral veins.
(b) Superior sagittal sinus. There are ten named dural venous sinuses. The brain
drains centrifugally into the superficial system and centripetally towards the deep
cerebral system.
Thrombus in the sinus system is diagnosed with either CT or MR; the abnormal
thrombus can be discerned from the adjacent flowing blood giving rise to the ‘empty
delta’ sign on contrast-enhanced images.
(c) Confluence of sinuses (or torcular herophili).
(d) Sigmoid sinus. These empty into the jugular vein on each side. usually the right
jugular vein is more dominant and therefore larger.
The straight and superior sagittal sinuses join at the torcula to form the transverse
sinus on each side which run antero-laterally to become the sigmoid sinuses.
(e) Basal vein of Rosenthal. The deep cerebral system consists most centrally of the
two internal cerebral veins, which run posteriorly in the roof of the third ventricle
inferior to the corpus callosum and join the basal vein of Rosenthal, as well as
posterior fossa veins to form the deep cerebral vein (of Galen). This ascends for a
short distance to join the inferior sagittal sinus and form the straight sinus (which are
only faintly seen on this study).
case 17
(a) Right interlobar pulmonary artery. The right interlobar artery lies lateral to
bronchus intermedius. This is useful in the recognition of these structures on a PA
chest radiograph.
(b) Left subclavian artery.
(c) Bronchus intermedius.
(d) Azygos vein. Note the right paratracheal stripe which lies superior to the azygos
vein.
(e) Left main pulmonary artery.
case 18
(a) Left pectoralis major muscle.
(b) Subareolar area.
(c) Nipple.
(d) Infra-mammary fold.
(e) Medio-lateral oblique (MLO) view of the left breast. With a properly positioned
MLO view the pectoralis muscle is seen obliquely across the top of the film extending
inferiorly to the level of a line drawn perpendicularly through the nipple to the muscle
(the posterior nipple line). The nipple should be in profile so the subareolar tissue is
adequately imaged. The infra-mammary fold should be visible so the inferior breast
has been adequately imaged.
The other view utilized in breast imaging is the cranio-caudal (CC) view.
MRI of the breast has gained widespread acceptance for the purposes of breast
imaging in screening, staging in primary and recurrent cancer, biopsy, treatment
response and evaluating breast augmentation.
case 19
(a) Acromion.
(b) Intertubercular groove.
(c) Lesser tuberosity.
(d) Coracoid process.
(e) Clavicle.
case 20
aorta
(a) Coeliac artery.
(b) Left renal vein. The left renal vein is situated inferior to the superior mesenteric
artery, anterior to the aorta.
(c) Gastric antrum. The gastric antrum is located anteriorly in contrast to the fundus,
which lies more posteriorly.
(d) Head of pancreas.
(e) Left lobe of liver.
Comments
Post a Comment