ABR flashcards

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

BI-RADS category 3

Probably benign finding with less than 2% likelihood of malignancy; short-interval follow-up mammography at 6 months is recommended rather than immediate biopsy.

Fine linear branching calcifications

Mammographic calcifications that are thin, irregular, and follow ducts; they are suspicious for ductal carcinoma in situ and generally warrant biopsy.

Breast MRI indication

Screening in BRCA mutation carriers and evaluation of disease extent or an occult primary presenting with axillary metastases; MRI has the highest sensitivity of any breast modality.

Subendocardial delayed enhancement

Late gadolinium enhancement confined to the subendocardium in a coronary territory indicates ischemic myocardial injury; transmural enhancement indicates completed infarction.

Stanford type A dissection

Aortic dissection involving the ascending aorta regardless of entry tear site; it is a surgical emergency, whereas type B dissection spares the ascending aorta.

Coronary CTA negative predictive value

A technically adequate coronary CT angiogram without plaque or stenosis has a very high negative predictive value, useful for excluding coronary disease in low-to-intermediate risk patients.

LI-RADS LR-5

Definite hepatocellular carcinoma: arterial phase hyperenhancement with washout and an enhancing capsule in an at-risk liver, allowing treatment without confirmatory biopsy.

Hemangioma enhancement pattern

Peripheral nodular enhancement with centripetal fill-in that matches blood pool on delayed images; classic for hepatic hemangioma and requiring no further workup.

Small bowel obstruction threshold

Small bowel loops greater than 3 cm in caliber suggest obstruction; the colon normally measures up to 6 cm and the cecum up to 9 cm.

Bosniak category IV

Cystic renal mass with enhancing nodular solid components, thick irregular walls, or thick septa; it is malignant in most cases and requires surgical management.

Lipid-rich adrenal adenoma

Adrenal nodule with unenhanced CT attenuation below 10 Hounsfield units, reflecting intracellular lipid; this is diagnostic of a benign adenoma needing no further imaging.

PI-RADS

Prostate Imaging Reporting and Data System score from 1 to 5 on multiparametric MRI; scores of 4 or 5 warrant targeted biopsy because significant cancer is likely.

TIPS gradient goal

Transjugular intrahepatic portosystemic shunt aims for a post-procedure portosystemic pressure gradient below 12 mmHg to reduce variceal bleeding and refractory ascites.

Postembolization syndrome

Fever, pain, and nausea occurring days after tumor or fibroid embolization; it is expected and managed supportively but must be distinguished from abscess.

Codman triangle

Periosteal elevation at the margin of an aggressive bone lesion such as osteosarcoma; the lifted periosteum forms a triangular shell of new bone.

Giant cell tumor location

Eccentric lytic soap-bubble lesion in the epiphysis of a long bone extending to the articular surface in a skeletally mature adult aged 20 to 40.

DXA osteoporosis threshold

Osteoporosis is a T-score of -2.5 or lower at the lumbar spine, total hip, or femoral neck; scores between -1.0 and -2.5 define osteopenia.

Hyperdense MCA sign

Noncontrast CT hyperattenuation of the middle cerebral artery caused by acute thrombus; it indicates proximal occlusion and supports endovascular thrombectomy decisions.

Dawson fingers

Ovoid perivenular demyelinating plaques oriented perpendicular to the lateral ventricles on sagittal MRI, characteristic of multiple sclerosis.

Epidural hematoma shape

Biconvex or lentiform extra-axial hemorrhage that does not cross sutures because the dura is tightly adherent there; usually arterial from middle meningeal injury.

Sensitivity formula

Sensitivity equals true positives divided by true positives plus false negatives; it is the proportion of diseased patients correctly identified and does not depend on prevalence.

ALARA principle

Radiation exposures should be kept as low as reasonably achievable while obtaining the needed diagnostic information, using time, distance, shielding, and optimized protocols.

Superscan

Bone scan with diffusely increased skeletal uptake and faint or absent renal and soft tissue activity; causes include diffuse prostate metastases and metabolic bone disease.

High-probability V/Q scan

Ventilation-perfusion scan showing two or more mismatched segmental or subsegmental perfusion defects with normal ventilation; it is highly specific for pulmonary embolism.

HIDA nonvisualization

Absent gallbladder activity on a hepatobiliary iminodiacetic acid scan persisting beyond four hours, including after morphine augmentation, indicates acute cholecystitis.

Pyloric stenosis target sign

Ultrasound showing pyloric muscle thicker than 3 mm and canal length over 14 mm in an infant aged 3 to 6 weeks with nonbilious projectile vomiting.

Metaphyseal corner fracture

Classic metaphyseal lesion in an infant, appearing as a bucket-handle or corner fracture from torsional shearing; it is highly specific for nonaccidental trauma.

Intussusception target sign

Ultrasound showing bowel within bowel as concentric rings in a child aged 6 months to 3 years with colicky pain; ileocolic disease is most common and often enema-reducible.

Lung cancer screening criteria

Annual low-dose CT for adults aged 50 to 80 with at least a 20 pack-year smoking history who currently smoke or quit within 15 years.

Hampton hump

Wedge-shaped pleural-based peripheral opacity on chest radiograph representing pulmonary infarction from pulmonary embolism; usually a late and nonspecific finding.

Sonographic Murphy sign

Maximal tenderness elicited when the transducer presses directly over the gallbladder; it supports acute cholecystitis when combined with wall thickening and pericholecystic fluid.

DVT compression ultrasound

Failure of a vein to collapse completely under graded transducer pressure is the primary diagnostic criterion for lower extremity deep vein thrombosis.