RANZCR Anatomy flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Posterior limb internal capsule

Contains corticospinal and corticobulbar tracts plus sensory thalamocortical fibres; lacunar infarction here causes dense contralateral hemiparesis and is a classic hypertensive small-vessel lesion site.

Foramen ovale contents

Transmits the mandibular division of the trigeminal nerve (V3) and the accessory meningeal artery; it lies in the greater wing of the sphenoid, posterolateral to the foramen rotundum.

Cavernous sinus contents

Contains the internal carotid artery and cranial nerves III, IV, V1, V2 and VI; nerve VI lies most laterally within the sinus and is therefore often affected first by cavernous pathology.

Cerebellopontine angle masses

Vestibular schwannoma is the commonest, broadening the internal auditory canal; meningioma typically has a dural tail and calcification; epidermoid is CSF-density and restricts diffusion.

Circle of Willis components

Formed by anterior communicating, paired anterior cerebral, paired internal carotid, paired posterior communicating and paired posterior cerebral arteries; the basilar artery supplies the posterior circulation.

Tracheal bifurcation level

The carina lies at approximately the T4–T5 level in adults, at the level of the aortic arch and the azygos vein arching over the right main bronchus.

Azygos fissure

A normal variant where the azygos vein invaginates pleura, creating a teardrop-shaped azygos lobe at the right lung apex with a visible fissure line.

Porta hepatis contents

Transmits the portal vein posteriorly, proper hepatic artery anteromedially and common bile duct anterolaterally; the portal triad is enveloped by the hepatoduodenal ligament.

Renal artery relations

The right renal artery passes posterior to the inferior vena cava; the left renal vein crosses anterior to the aorta between the superior mesenteric artery and aorta, where it may be compressed.

Inguinal canal boundaries

Anterior wall is aponeurosis of external oblique; posterior wall is transversalis fascia and conjoint tendon; floor is inguinal ligament; roof is internal oblique and transversus abdominis.

Scapholunate interval

Normal scapholunate interval is under 3 mm; widening with a Terry Thomas sign indicates scapholunate ligament injury and risks dorsal intercalated segment instability.

Ankle mortise radiograph

Assesses medial, lateral and posterior malleoli plus talar dome; the medial clear space should be under 4 mm and equal to the superior clear space.

Hounsfield unit references

Water is 0 HU, air about −1000 HU, fat −100 to −50 HU, acute blood 50–80 HU, bone over 400 HU; these anchors permit density characterisation on unenhanced CT.

MRI T1 versus T2 weighting

Short TR and TE gives T1 weighting (fat bright, fluid dark); long TR and TE gives T2 weighting (fluid bright); FLAIR suppresses CSF to reveal periventricular lesions.

Doppler spectral waveform

High-resistance arteries show sharp systolic peaks with low diastolic flow (external carotid); low-resistance vessels show broad systolic peaks and continuous diastolic flow (internal carotid, renal).

ALARA principle

Dose optimisation principle requiring exposures to be as low as reasonably achievable, achieved through collimation, shielding, appropriate kVp/mAs selection and minimising repeat examinations.

ASPECTS score

Ten-point scoring system on unenhanced CT in middle cerebral artery stroke; one point subtracted per region of early ischaemic change, with ≤6 indicating large infarct.

CT pulmonary angiography timing

Bolus tracking with threshold in the main pulmonary artery; adequate study shows dense contrast in pulmonary arteries with minimal artefact from dense superior vena cava contrast.

Aortic dissection classification

Stanford A involves the ascending aorta and requires urgent surgery; Stanford B spares the ascending aorta and is usually managed medically or with endovascular repair.

Bowel ischaemia CT signs

Findings include bowel wall thickening or thinning, pneumatosis intestinalis, portal venous gas, reduced mural enhancement and mesenteric stranding; pneumatosis with portal gas implies transmural infarction.

Ovarian torsion imaging

Enlarged oedematous ovary with peripherally displaced follicles, twisted vascular pedicle (whirlpool sign) and reduced or absent Doppler flow; normal Doppler does not exclude torsion.

Ectopic pregnancy diagnosis

Positive pregnancy test with empty uterus, adnexal mass and free fluid; discriminatory human chorionic gonadotropin level guides whether transvaginal ultrasound should show an intrauterine sac.

Bosniak cyst classification

Bosniak I and II are benign simple cysts; IIF requires follow-up; III needs surgery or surveillance; IV is clearly malignant with enhancing solid components.

Pulmonary nodule follow-up

Fleischner guidance uses nodule size and solid versus subsolid morphology plus patient risk; solid nodules under 6 mm in low-risk patients generally need no follow-up.

LI-RADS major features

Arterial phase hyperenhancement, non-peripheral washout, enhancing capsule, size and threshold growth; these features assign categories from LR-1 to LR-5 in at-risk livers.

Hydrocephalus versus atrophy

Hydrocephalus shows enlarged ventricles with transependymal oedema and effaced sulci; ex vacuo enlargement shows prominent sulci with proportionate ventricular enlargement.

Multiple sclerosis lesion distribution

Periventricular, juxtacortical, infratentorial and spinal cord lesions, often ovoid and perpendicular to ventricles (Dawson fingers); dissemination in space and time establishes diagnosis.

Salter-Harris fracture types

I involves physis alone; II physis and metaphysis; III physis and epiphysis; IV all three; V is physeal crush; higher grades carry greater growth arrest risk.

Osteosarcoma radiographic features

Aggressive metaphyseal lesion in a young patient with ill-defined margins, periosteal reaction (Codman triangle, sunburst) and matrix mineralisation; MRI stages medullary and soft tissue extent.

Thyroid ultrasound features

Malignancy predictors include solid hypoechoic composition, irregular margins, taller-than-wide shape, microcalcifications and cervical lymphadenopathy; these drive fine needle aspiration thresholds.

Adrenal adenoma washout

Absolute washout above 60% or relative washout above 40% on delayed contrast CT indicates adenoma; lipid-rich adenomas show under 10 HU on unenhanced imaging.

Chest radiograph silhouette sign

Loss of a normal border indicates adjacent same-density pathology: right heart border with right middle lobe, left heart border with lingula, and diaphragm with lower lobe.