Examination 8
case 01
(a) Gallbladder. The gallbladder stores about 50 ml of bile. Its blood supply is from
the cystic artery, a branch of the right hepatic artery. It drains into segment 5 of the
liver where it also receives a collateral blood supply. There are folds in the mucous
membrane of the cystic duct (spiral valve of Heister) which together with underlying
smooth muscle serve to regulate the flow of bile.
(b) Portal vein. It forms at the confluence of the splenic and superior mesenteric vein
at L1/L2 level, posterior to the neck of the pancreas.
The portal vein provides 75% of the liver's inflow with the common hepatic artery
supplying the remainder. Of note however, if there is a malignancy within the liver
(primary or secondary) its blood supply is invariably arterial in origin.
(c) Right hemidiaphragm. The lung above the diaphragm is not seen as air
conducts the ultrasound poorly. If there is a plural effusion however, it will be
apparent in this region.
(d) Common hepatic artery. The region of the liver containing the common hepatic
artery, common hepatic duct and portal vein is known as the porta hepatis.
(e) Common bile duct. This becomes the common bile duct (CBD) after the confluence
with the cystic duct. The normal diameter of the CBD is variable but more than 8 mm
can be pathological, though it dilates with increasing age. Generally 1 mm per decade
gives a useful approximation.
case 02
(a) Vastus medialis muscle.
(b) Vastus lateralis muscle.
(c) Anterior cruciate ligament. There is an aide memoire for remembering the orientation
of the cruciate ligaments.
The anterior cruciate ligament is extrasynovial, intracapsular and arises from the
intercondylar notch in the tibia and rises towards the anterior aspect of the lateral
femoral condyle. Anterior – Backwards, Upwards and Laterally (ABUL).
The posterior cruciate ligament is intrasynovial, extracapsular and arises from the
posterior tibial plateau and rises towards the posterior aspect of the medial femoral
condyle. Posterior – Upwards, Medially and Forwards (PUMF).
(d) Conjoined tendon. The conjoined tendon is the combination of the lateral collateral
ligament and biceps femoris tendon inserting onto the fibular head. The lateral
stabilizing ligaments comprise:
Superficial layer – iliotibial band anteriorly merging with the biceps femoris tendon
posteriorly
Intermediate layer – postero-lateral collateral ligament
Deep layer – popliteus tendon.
(e) Hyaline cartilage of lateral femoral condyle.
case 03
(a) Right vestibule. This communicates posteriorly with the three semicircular canals
and anteriorly with the cochlear.
(b) Right cochlear. This contains the cell bodies of the cochlear nerve within the
modiolus.
(c) Right head of malleus. The handle of the malleus is attached to the tympanic
membrane whilst the head articulates with the body of the incus.
(d) Right body of incus. The body of the incus articulates with the malleus at the
incudomallear joint. The long process of the incus articulates with the head of the
stapes.
(e) Right mastoid air cells. These communicate with the attic via the aditus ad
antrum.
case 04
(a) Valve in left basilic vein.
(b) Left cephalic vein. The cephalic vein, in the forearm and at the elbow, is the
primary vein utilized in fashioning arteriovenous fistulae (AVF) for haemodialysis.
The arrowed segment is known as the terminal arch and is notorious for developing
stenoses secondary to distal AVF.
(c) Left subclavian vein. This is a continuation of the axillary vein at the outer border
of the first rib and combines with the jugular vein at the sternal end of the clavicle.
(d) Left brachiocephalic vein.
(e) Superior vena cava (SVC).
case 05
(a) Posterior junction line. The posterior junction line is seen in about 30% of PA chest
radiographs and is formed when the x-ray beam is tangential to the apposition of the
postero-medial portion of both upper lobes posteriorly. On the PA radiograph it runs
from above the clavicles to the arch of the aorta and is projected through the trachea.
The line comprises four layers – two parietal and two visceral pleural layers. The line
may become a stripe if there is a significant amount of mediastinal fat in between the
two lungs.
Abnormal bulging of this line suggests mass lesions of the oesophagus, lymphadenopathy
or neurogenic masses.
(b) Left main pulmonary artery. The left main pulmonary artery is more cranial in
position than the right main pulmonary artery since it is superior to the left main
bronchus just prior to its bifurcation.
(c) Left axillary fold.
(d) Right lateral border of the sternum.
(e) Right sternoclavicular joint. The sternoclavicular joint is a synovial joint separated
by a flat articular disc. There are four strong ligaments (anterior and posterior
sternoclavicular, interclavicular and costoclavicular) and a strong fibrous capsule.
As a result trauma to the joint rarely causes disruption but instead is associated with
clavicular fracture.
case 06
(a) Aortic root.
(b) Right coronary artery (RCA).
(c) Left atrial appendage.
(d) Left anterior descending artery.
(e) Aberrant left circumflex artery (LCX). In this case the anomalous LCX arises from
the right sinus of Valsalva and shares a common origin with the RCA. It then runs
behind the aortic root to reach the left atrioventricular groove and supply the lateral
left ventricular wall. The anomalous LCX may have a separate origin from the RCA in
the right sinus of Valsalva.
Anomalous coronary arteries are seen in 0.6–1.5% of catheter angiograms and
an anomalous LCX is the commonest normal variant of coronary artery
anatomy. CT coronary angiography is the examination of choice if anomalous
coronary artery anatomy is suspected, and it is essential to know the variant
anatomy if percutaneous coronary intervention or aortic root surgery is being
considered.
case 07
(a) Right femoral vein.
(b) Right ovary.
(c) Rectum.
(d) Left ovary.
(e) Left femoral artery.
MRI is commonly used in assessing both the male and the female pelvis. Fat saturation
techniques can enable the pelvic organs to be well visualized. Ovarian cysts can
be seen, which are often small and multiple in pre-menopausal females.
case 08
(a) Left caudate nucleus.
(b) Left lentiform nucleus. This consists of two components – the lateral putamen and
medial globus pallidus.
Together the lentiform and caudate nuclei are known as the corpus striatum. They
are part of the extrapyramidal system of the motor system, involved in the coordination
of reflexes and posture.
(c) Splenium of the corpus callosum. The corpus callosum connects both cerebral
hemispheres. The splenium is the bulky posterior part, anterior to which lies the body,
genu and rostrum respectively.
(d) Right thalamus.
(e) Anterior limb of the right internal capsule.
case 09
(a) First metatarso-phalangeal joint. A common place to look for primary osteoarthritis
which results clinically in hallux rigidus. If rheumatoid arthritis affects this joint
then the result is hallux valgus. Gout also has a predilection for this joint although is
now rarely seen on imaging due to the efficacy of medical management.
(b) Base of the second metatarsal. This is held in place by a mortice made by the
medial, middle and lateral cuneiform bones and is informally referred to as the
Lisfranc joint. It is important to verify alignment on trauma films to rule out a midfoot
(Lisfranc) dislocation:
On the AP view the medial margin of the base of the second metatarsal should
align with the medial margin of the middle cuneiform.
On the oblique view the medial margin of the base of the third metatarsal should
align with the medial margin of the lateral cunieform.
(c) Tuberosity of the fifth metatarsal. A common place of avulsion fractures due to
inversion injuries. If the fracture line lies within the proximal diaphysis (distal to the
joint line of the fourth tarsometatarsal joint), then this fracture is known as a Jones’
fracture, which notoriously results in delayed or non-union. It is not an avulsion
fracture. The Jones’ fracture is named after Sir Robert Jones (1857–1933), Professor of
Orthopaedic Surgery at Liverpool University.
(d) Calcaneum.
(e) Os tibiale externum. This can lie entirely separately within the tendon of tibialis
posterior (type 1) or have a cartilaginous (type II) or osseous (type III) connection with
the medial aspect of the navicular bone.
case 10
(a) Right vertebral artery.
(b) Left common carotid artery. The left internal carotid artery just superior to this is
seen to be occluded on this study.
(c) Brachiocephalic trunk (innominate artery).
(d) Left subclavian artery.
(e) Left vertebral artery arising directly from the arch of the aorta. This occurs in 6%
of the population, with the most frequent location for its origin being between the left
common carotid and subclavian arteries.
case 11
(a) Azygos vein.
(b) Bronchus intermedius.
(c) Right interlobar pulmonary artery. The right interlobar and upper lobe pulmonary
arteries both lie anterior to bronchus intermedius. (On the left side the pulmonary
artery lies posterior to the left main bronchus.)
(d) Right inferior pulmonary vein.
(e) Right superior pulmonary vein. The right pulmonary veins lie anterior to the
pulmonary arteries.
case 12
(a) Antero-inferior glenoid rim. This is an important region as it bears the attachment
of the anterior band of the inferior glenohumeral ligament (AIGHL). This is the
site of avulsion fracture sustained during anterior glenohumeral dislocation known
as a bony Bankart lesion. The classic Bankart lesion refers to avulsion of the anteroinferior
glenoid labrum along with the AIGHL and thus cannot be seen on
radiographs.
(b) Acromion process. The deltoid origin is broad and curved and extends around the
entire border of the acromion. Bony avulsion of the acromion is rare following trauma
though enthesopathy at the deltoid origin is a common degenerative feature on
radiographs.
(c) Coraco-acromial ligament (CAL). The CAL is a narrow but tough ligament that
arises from the anterior tip of the acromial undersurface. Its origin may form a bony
enthesophyte that has been implicated in the aetiology of supraspinatus tendon tears.
The CAL is thought to contribute to the clinical condition of sub-acromial impingement
and it is routinely divided during a sub-acromial decompression procedure.
(d) Coracoid process. The coracobrachialis is a long muscle that arises from the
coracoid process and inserts distally on the antero-medial surface of the humeral
diaphysis.
(e) Subscapularis. As its name suggests the subscapularis is a broad multi-pennate
muscle that lies beneath the scapula. It becomes narrower laterally, as does the shape
of the scapula, to form a broad tendon that inserts on the lesser tuberosity of the
humerus which acts to internally rotate the shoulder.
case 13
(a) Right thyroid lobe.
(b) Left common carotid artery.
(c) Brachiocephalic trunk.
(d) Left pulmonary artery.
(e) Left atrium.
case 14
(a) Inferior vena cava.
(b) Gastric antrum.
(c) Splenic artery.
(d) Crus of the right hemidiaphragm.
(e) Lateral limb of the right adrenal gland.
case 14
(a) Left pectoralis minor muscle.
(b) Superior vena cava.
(c) Left superior intercostal vein.
(d) Right erector spinae muscle.
(e) Aberrant right subclavian artery.
case 16
(a) Occipital bone.
(b) Anterior arch of the atlas (C1).
(c) Spinous process of C2.
(d) Dens (odontoid peg).
(e) Right lateral mass of C1.
case 17
(a) Condylar head. The temporomandibular joint is a synovial joint between the
condyle of the mandible and the articular fossa of the temporal bone.
(b) Articular fossa. The head of the mandible sits in the fossa at rest.
(c) Lateral pterygoid muscle. This attaches to the anterior band of the articular
disc.
(d) Anterior band of the articular disc. The articular disc has an anterior and posterior
band with a thin zone in the middle. The disc is attached to the joint capsule. The joint
space is divided into upper and lower compartments by the disc.
(e) Articular eminence. The head of the condyle moves anteriorly against the
eminence on jaw opening.
case 18
(a) Radial styloid epiphysis.
(b) Base of thumb epiphysis.
(c) Hook of hamate.
(d) Capitate.
(e) Trapezoid.
case 19
(a) Right temporalis muscle.
(b) Septum pellucidum.
(c) Falx cerebri.
(d) Superior sagittal sinus.
(e) Cavum septum pellucidum. Cavum septum pellucidum (CSP) is a potential space
filled with cerebrospinal fluid that occurs between the leaflets of the septum pellucidum.
It is limited posteriorly by the fornix, unlike cavum vergae, which extends as far
back as the splenium of the corpus callosum. It is present in 100% of fetuses with
approximately 85% fusing by 6 months.
case 20
(a) Odontoid peg.
(b) Left superior orbital fissure.
(c) Sagittal suture.
(d) Right greater wing of sphenoid.
(e) Right mastoid process.
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