EDiR flashcards

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

Fleischner nodule follow-up threshold

A solid solitary pulmonary nodule of 6 to 8 mm in an at-risk adult warrants follow-up CT at 6 to 12 months, with later optional imaging, rather than immediate biopsy.

Stanford type A dissection

Aortic dissection involving the ascending aorta; a surgical emergency because of the risk of rupture, pericardial tamponade and coronary or cerebral malperfusion.

Subendocardial delayed enhancement

Late gadolinium enhancement confined to the subendocardium and following a coronary territory, which indicates myocardial infarction rather than non-ischaemic cardiomyopathy.

Right heart strain CT signs

In acute pulmonary embolism, a right ventricular to left ventricular diameter ratio above 1.0 on CT, often with septal bowing, indicates right heart strain and adverse prognosis.

LI-RADS 5 criteria

Definite hepatocellular carcinoma: an observation of at least 10 mm in a cirrhotic liver showing arterial phase hyperenhancement plus washout, enhancing capsule or threshold growth.

Haemangioma centripetal fill-in

A liver haemangioma shows peripheral nodular discontinuous enhancement that progressively fills towards the centre and becomes isointense with blood pool on delayed phases.

Small bowel obstruction transition point

Dilated small bowel loops over 3 cm with a discrete transition zone on CT identify mechanical obstruction and suggest both its cause and its level.

Bosniak IV cyst

A cystic renal mass with enhancing nodular or solid components, which is malignant in a high proportion of cases and therefore requires surgical excision.

Lipid-rich adrenal adenoma

An adrenal mass measuring less than 10 Hounsfield units on unenhanced CT, indicating intracellular lipid and a benign adenoma, so no further workup is required.

PI-RADS 4 lesion

A prostate lesion with high likelihood of clinically significant cancer on multiparametric MRI, usually prompting targeted biopsy because of abnormal diffusion or perfusion findings.

Codman triangle

Elevated periosteum at the margin of an aggressive bone lesion, seen as a triangular shell of new bone; classic for osteosarcoma but not specific to it.

DXA osteoporosis threshold

A T-score of minus 2.5 or lower at the lumbar spine, total hip or femoral neck defines osteoporosis; scores between minus 1.0 and minus 2.5 define osteopenia.

Giant cell tumour location

An eccentric, lytic, expansile lesion arising in the epiphysis of a long bone after growth plate closure, typically in adults aged 20 to 40 years.

ACL tear secondary signs

Bone contusions of the lateral femoral condyle and posterior tibial plateau, together with a Segond fracture, suggest anterior cruciate ligament rupture on MRI.

Extradural haematoma shape

A biconvex or lentiform collection that does not cross cranial sutures, usually from middle meningeal artery injury, and constitutes a neurosurgical emergency.

McDonald dissemination criteria

Multiple sclerosis diagnosis requires lesions disseminated in space, such as periventricular, cortical or juxtacortical, infratentorial and spinal cord lesions, and disseminated in time.

Vestibular schwannoma ice-cream cone

A cerebellopontine angle mass that widens the internal acoustic meatus and shows tapered extension into the canal, the typical appearance of a vestibular schwannoma.

Hyperdense MCA sign

A non-contrast CT finding of increased attenuation within the middle cerebral artery, indicating acute thrombus, although it is present in only a minority of strokes.

BI-RADS category 4

A suspicious mammographic finding with a 2 to 95 percent probability of malignancy that warrants tissue sampling, usually by image-guided core biopsy.

Stereotactic breast biopsy

Vacuum-assisted biopsy performed under mammographic guidance for calcifications or architectural distortion that is visible on mammography but cannot be seen on ultrasound.

Breast density category d

Extremely dense breast tissue on BI-RADS density assessment, which lowers mammographic sensitivity and may prompt supplemental ultrasound or MRI screening.

CRITOE elbow ossification

Order of appearance of elbow ossification centres: capitellum, radial head, internal epicondyle, trochlea, olecranon and external epicondyle, at roughly 1, 3, 5, 7, 9 and 11 years.

Pyloric stenosis ultrasound criteria

Hypertrophic pyloric stenosis is diagnosed when pyloric muscle thickness is 3 mm or more and canal length 15 mm or more in an infant with projectile vomiting.

Intussusception target sign

Transverse ultrasound appearance of bowel within bowel, showing concentric echogenic and hypoechoic rings; commonest in children aged 6 months to 3 years.

TIPS target gradient

A transjugular intrahepatic portosystemic shunt aims to reduce the portosystemic pressure gradient below 12 mmHg to control variceal bleeding or refractory ascites.

TACE in BCLC B

Transarterial chemoembolisation is the standard palliative treatment for intermediate-stage hepatocellular carcinoma with preserved liver function and no vascular invasion.

Uterine fibroid embolisation

Catheter-directed injection of particles into both uterine arteries to infarct symptomatic leiomyomas, an alternative to surgery in women wishing to preserve the uterus.

Deauville score 3

Uptake in a residual lymphoma mass greater than mediastinal blood pool but not higher than liver, generally regarded as a complete metabolic response.

Superscan bone scintigraphy

Intense uniform skeletal tracer uptake with faint or absent renal and soft tissue activity, suggesting diffuse metastatic disease or metabolic bone disease.

High-probability V/Q scan

Two or more mismatched segmental perfusion defects with normal ventilation, which carries a high probability of pulmonary embolism under the PIOPED criteria.

Hounsfield unit of water

By definition water measures 0 HU on CT, air about minus 1000 HU and dense bone up to plus 1000 HU or more, allowing tissue characterisation by attenuation.

Effective dose of abdominal CT

A standard abdominal CT delivers roughly 10 mSv effective dose, equivalent to several hundred chest radiographs or about three years of natural background radiation.