Examination 3
case 01
(a) Lesser trochanter of the right femur. The iliopsoas tendon attaches here. This is a
powerful flexor of the hip.
(b) Greater trochanter of the right femur. Gluteus medius and gluteus minimis attach
here. These tendons act to perform hip abduction and lateral rotation. They can
produce avulsion fractures of the greater trochanter in trauma.
(c) Left L5 transverse process. The ilio-lumbar ligament attaches here. Traction of this
ligament in pelvic trauma can cause an avulsion fracture of the transverse process. It
also acts as an anatomical landmark on MRI for identifying the L5 vertebral body.
(d) Pubic symphysis. It is a secondary cartilaginous joint.
(e) Left inferior pubic ramus. Adductor magnus and adductor brevis attach here
acting to adduct the hip.
case 02
(a) Left L5 nerve. At the level of the L5/S1 disc, the L5 nerve has already left the neural exit
foramen. It may become compromised by a far lateral L5 disc herniation in this position.
(b) Nucleus pulposus of L5/S1disc. This soft central component of the disc is surrounded
by the tough outer annulus fibrosus. Annular defects result in herniation of the nucleus
pulposus referred to as protrusions or extrusions, based upon their morphology. On
T2-weighted images the nucleus pulposus is of high signal and the annulus fibrosus is of
low signal intensity.
(c) Left lamina of L5 vertebra. Each lamina fuses in the midline to form the spinous
process. The lamina is partly or completely resected (laminectomy) during lumbar
disc surgery to facilitate access to the disc.
(d) Right psoas major muscle. This is a powerful hip flexor. In the clinical setting of
lumbar discitis it is common to see infection tracking from the disc space into the
psoas muscle to form a psoas abscess.
(e) Right S1 nerve.
case 03
(a) Internal carotid artery.
(b) Posterior communicating artery.
(c) Ophthalmic artery.
(d) Anterior cerebral artery.
(e) Middle cerebral artery.
There are four segments of the internal carotid artery:
1. cervical
2. petrous
3. lacerum
4. cavernous.
The circle of Willis is a ring of arteries in the suprasellar fossa that allows collateral
supply to the brain. It is made up of the anterior communicating artery, anterior
cerebral arteries, middle cerebral arteries, posterior communicating arteries and the posterior cerebral arteries. The circle is often susceptible to congenital anomalies and
has a variable degree of completeness, demonstrating conventional anatomy in
approximately one third of people.
case 04
(a) Right maxillary sinus. The maxillary sinus is one of the paranasal sinuses.
Opacification of the maxillary sinus on a plain radiograph may indicate an occult
facial bone fracture following trauma; however, it can also be opacified as a consequence
of other sinus diseases that result in loss of the normal sinus aeration.
(b) Left coronoid process (mandible). The coronoid process of the mandible is a site of
attachment of several muscles. Temporalis muscle attaches to its internal surface and
the tip while the masseter muscle is attached to the external surface.
(c) Left temporal styloid process. The styloid process of the temporal bone is a needlelike
bony structure that provides the attachment sites of several ligaments and muscles:
Stylohyoid ligament
Stylomandibular ligament
Styloglossus muscle
Stylohyoid muscle
Stylopharyngeus muscle.
(d) Left vertebral artery. The vertebral artery arises from the subclavian artery and
passes upwards through the vertebral foramina in the transverse process of the upper
six cervical vertebra. The artery enters the skull through the foramen magnum and, at
the level of the pons, the vertebral arteries from either side fuse to form the basilar
artery. Within the skull the vertebral artery gives off the posterior inferior cerebellar
artery and the anterior spinal artery.
The single basilar artery gives off many branches, the paired anterior inferior
cerebellar arteries, multiple bilateral pontine arteries, superior cerebellar arteries.
The basilar artery then bifurcates to form the posterior cerebral arteries often with
one being dominant and the main supply to the occipital lobe of the brain.
(e) Odontoid peg. The odontoid peg is embryologically the body of the C1 vertebra that
has fused to the body of C2 to form a prominence that facilitates rotation of the head.
case 05
(a) Right psoas muscle. The psoas shadow is blurred in 19% of the population and is
an insensitive sign of retroperitoneal pathology.
(b) Left kidney. The perinephric fat surrounding the kidney makes it visible.
(c) Right properitoneal fat line. This will not be visible in 18% of the population.
(d) Spleen. The outline cannot be identified in 42% of the population.
(e) Bladder outline. Like the kidneys, the distended bladder is visualized due to
surrounding perivesical fat.
case 06
(a) Left external iliac artery (not the common iliac artery as the internal iliac artery has
already branched off).
(b) Right internal iliac artery.
(c) Left common femoral artery (CFA). For arterial puncture in angiogram the
CFA needs to be targeted. With a puncture above (external iliac artery) or below
(superficial femoral artery) this, manual compression to secure haemostasis cannot be
performed adequately as the vessel cannot be compressed against bone. Furthermore,
arterial closure devices are only licensed for use in the CFA.
(d) Left deep artery of the thigh (profunda femoris artery (PFA)). This artery supplies
mainly the thigh while the superficial femoral artery (SFA) supplies the calf and foot.
Of these the former is more important because if the SFA is occluded the calf can be
supplied by collaterals from the PFA, whereas the opposite is not true.
(e) Right superficial femoral artery. This vessel is the continuation of the CFA after
the deep artery of the thigh (profunda femoris artery) has branched off. At the inferior
border of the femoral triangle it passes into the adductor canal (Hunter's or subsartorial
canal). It emerges distally in an opening in the adductor magnus known as the
adductor hiatus to become the popliteal artery.
case 07
(a) Vallecula. The valleculae are paired depressions situated either side of the median
glossoepiglottic fold. They separate the epiglottis from the base of the tongue and
serve to hold saliva before the swallowing reflex commences.
(b) Piriform fossa. This is a recess bounded medially by the aryepiglottic fold and
laterally by the thyroid cartilage. The internal branch of the superior laryngeal nerve is
located immediately deep to the mucosa in this region. Fish bones can become lodged
in this area.
(c) Laryngeal vestibule. This forms the opening into the larynx and is located above
the vestibular folds (false cords).
(d) Air in the trachea. The trachea extends from the lower part of the larynx, level
with the sixth cervical vertebra, to the upper border of the fifth thoracic vertebra. It is a
midline structure but passes inferiorly to lie just to the right of midline at the level of
the aortic arch (T4).
(e) Aortic arch impression.
There are three sites of natural oesophageal indentation which include the aortic arch
(T4 level), the left main bronchus (T5 level) where the indentation is left-sided and the
left atrium. Caustic strictures tend to occur at sites of oesophageal indentation since
transit of solids and liquids is slowed at these sites.
case 08
precession sequence)
(a) Left ventricle.
(b) Right ventricular outflow tract.
(c) Aortic root.
(d) Mitral valve.
(e) Papillary muscle. One of the two left ventricular papillary muscles is seen in this
image. The postero-medial and antero-lateral papillary muscles are each attached to
both leaflets of the mitral valve via the chordae tendinae and prevent mitral valve
prolapse during ventricular systole.
This image is a single frame from a cardiac MR white blood cine (steady state free
precession) examination. This 3-chamber view of the left ventricular outflow tract
(LVOT) when viewed as a cine is good for visual assessment of the aortic valve and
LVOT, and can also demonstrate mitral valve pathology.
case 09
(a) Ascending colon.
(b) Right gluteus medius muscle.
(c) Urinary bladder.
(d) Spleen.
(e) Left duplex kidney.
CTU is now a widely accepted modality used for the investigation of haematuria.
Depending on local policy, different phases of imaging are obtained, which must
include a urographic phase.
Images should be interpreted using axial, sagittal and coronal planes to ensure both
ureters have been adequately assessed in their entirety.
The commonest anomaly of the kidney is duplication of the collecting system,
which occurs in 1% of the population. This is more common in females than males
and varies from a bifid renal pelvis to complete duplication of the ureter. In this case,
the ureter draining the upper pole moiety inserts lower into the bladder than that
draining the lower moiety. The upper ureter is more likely to obstruct and the lower
pole ureter more likely to reflux.
When evaluating CTU, look carefully for any anomaly in ureteric anatomy as one
ureter may be involved in tumour or with renal calculi, and the other may be normal.
case 10
(a) Triangular fibrocartilage. This fibrocartilaginous disc contributes to stability of the
distal radio-ulnar joint (DRUJ). Degenerative and traumatic tears of this structure are
common causes of mechanical ulnar sided wrist pain.
(b) Scapho-lunate (SL) ligament. This short ligament is made up of volar, central and
dorsal components, which contribute to stability of the proximal carpal row. Tears of
the SL ligament lead to volar-flexion of the scaphoid and dorsi-flexion of the lunate
producing a dorsal intercalated segment instability (DISI) appearance on lateral
radiographs.
(c) Hamate. This bone occupies the distal carpal row, articulating with the fourth
and fifth metacarpals. It possesses a hook-shaped process on its volar surface
which bears an attachment of the flexor retinaculum. The hook may become
fractured following falls onto the palm, particularly whilst holding racket
handles.
(d) Carpo-metacarpal joint of the thumb. This is a synovial saddle joint which is a
common site for early osteoarthrosis in the hand.
(e) Capitate. This is the largest carpal bone and the first to ossify.
case 11
(a) Crista galli. This is a median ridge of bone that projects from the cribriform plate
of the ethmoid bone.
(b) Left maxillary ostium. This is the opening of the maxillary sinus, located in the
middle meatus of the lateral nasal cavity.
(c) Left uncinate process. This is a bony projection, formed from the medial wall of
the maxillary sinus.
(d) Left infundibulum. This is the channel which drains the maxillary sinus.
(e) Right lamina papyracea. This is the paper-thin bony wall between the orbits and
the ethmoid sinuses.
case 12
(a) Myometrium of uterus.
(b) Amniotic fluid.
(c) Endometrium of uterus.
(d) Urinary bladder.
(e) Crown–rump length (CRL).
Ultrasound is the main imaging modality used for assessment of the fetus. If there are
concerns following ultrasound, MRI can be useful for further evaluation.
The role of ultrasound in the first trimester is to confirm a viable intrauterine
pregnancy, determine fetal number and date the pregnancy. Nuchal thickness scanning
can also be performed where increased thickness (>3 mm) is associated with
chromosomal abnormalities, cardiac anomalies and skeletal dysplasia.
The CRL is measured to ascertain estimated due date. If CRL is more than or equal
to 5 mm, a fetal heart beat should always be detectable. Absence of cardiac activity in
embryos >5 mm is indicative of a non-viable fetus.
case 13
(a) Opisthion. This is the midpoint of the posterior aspect of the foramen magnum. Its
anterior counterpoint is the basion.
(b) Anterior arch of C1 (or atlas). The C1 (atlas), C2 (axis) and C7 vertebrae are
atypical.
C1 is a ring of bone with no body; the odontoid peg of C2 (dens) represents the body
of C1. The articulation between C1 and C2 at the dens is called the atlanto-axial joint
and is where rotation of the skull occurs. The articulation between the lateral masses
of C1 and occipital condyles of the skull base is where nodding and lateral flexion
occur.
(c) Odontoid peg (or dens).
(d) Posterior arch of C7.
(e) Spinous process of C7.
The C8 is a nerve root with no vertebral body. It exits the spinal canal between C7 and
T1 vertebrae. Therefore, cervical roots exit above pedicles of the same numbered
body. In the thoracic and lumbar spine, nerve roots exit below the pedicles of the
same numbered body.
case 14
(a) Right fibular (or common peroneal) artery.
(b) Right posterior tibial artery. This artery lies deep to soleus as it runs inferiorly,
becoming superficial close to the ankle joint where it it can be palpated behind the
medial malleolus.
(c) Left anterior tibial artery. This is the first terminal branch of the popliteal artery. It
passes forward through an opening in the intraosseus membrane and continues
inferiorly. It passes anteriorly across the ankle joint beneath the extensor retinaculum
to become the dorsalis pedis artery of the foot.
These three vessels (A, B and C) constitute the ‘run-off’ when talking about peripheral
vascular disease. ‘In-line flow’ means at least one vessel is patent from the origin
to the ankle without reliance on collateral vessels. Recent evidence suggests the
longevity for below knee intervention depends upon the total number of patent
vessels.
(d) Right lateral plantar artery. This together with the other branch from the dorsalis
pedis, the medial plantar artery, feed into the deep plantar arch.
(e) Left dorsalis pedis artery.
case 15
(a) Rhomboid fossa.
(b) Medial border of the right scapula.
(c) Right atrium.
(d) Spine of left scapula.
(e) Right-sided aortic arch. A right-sided aortic arch results from persistence of the
right fourth branchial arch. It is more commonly seen in conjunction with an aberrant
left subclavian artery. When right aortic arch is present with mirror image branching
pattern (left brachiocephalic trunk, right common carotid and subclavian arteries) it is
almost always associated with congenital heart disease, especially the cyanotic type.
case 16
(a) Posterior pituitary. The pituitary gland has a distinct appearance on T1-weighted
sagittal MRI images. The anterior gland is isointense with white matter. The posterior
pituitary signal is high because of the presence of neuropeptides in this part of the
gland.
(b) Clivus. The clivus has high signal on all sequences because of bone marrow.
(c) Opisthion. This is the posterior cortical margin of the foramen magnum.
(d) Adenoidal tissue.
(e) Optic chiasm.
case 17
(a) Uncinate process of the pancreas.
(b) Inferior vena cava.
(c) Left renal vein.
(d) Splenic vein.
(e) Duodenum (D1/D2).
case 18
(a) Left pterygopalatine fossa. This communicates laterally with the infratemporal
fossa, and superiorly with the orbit and middle cranial fossa. Therefore, it may
facilitate spread of pathology between these spaces.
(b) The maxillary division of the V cranial (trigeminal) nerve. This runs through the
foramen rotundum and into the orbit via the inferior orbital fissure.
(c) Left carotid canal. This contains the internal carotid artery.
(d) Right jugular foramen. This contains the internal jugular vein, IX, X, XI cranial
nerves, inferior petrosal sinus and branches of the ascending occipital and pharyngeal
arteries.
(e) Right foramen lacerum. The internal carotid artery runs through its posterior
aspect after emerging from the carotid canal.
case 19
(a) Right internal thoracic (mammary) artery. The internal thoracic artery arises from
the inferior subclavian artery and descends deep to the internal intercostal muscles and
costal cartilages to supply the anterior chest wall and breasts, and divides at the level of
the sixth intercostal space into the superior epigastric and musculophrenic arteries.
(b) Right internal thoracic (mammary) vein. This vein lies medial to the artery.
(c) Right main pulmonary artery.
(d) Left infraspinatus muscle.
(e) Left latissimus dorsi muscle.
case 20
(a) Appendix.
(b) Terminal ileum.
(c) Ilio-pectineal line.
(d) Sigmoid colon.
(e) Ileo-caecal valve.
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