B SIGN

Bat Wing Appearance-AKA Angel Wing-pattern of pulmonary edema which involves perihilar regions and spares cortex of lung

Berry Aneurysm-an intracranial aneurysm most often occurring in the Circle of Willis, particularly at the junction of major vessels in the anterior circulation

Blade of Grass Sign-AKA flame sign; advancing, wedge-shaped, osteolytic margin of active Paget disease of bone; usually seen in diaphysis

Beveled Edge Appearance-asymmetric erosion of the inner and outer tables of the skull usually seen with eosinophilic granuloma

Bird's Beak Sign-AKA Rat-tail Sign; irregularly marginated tapering of esophagus in achalasia

Bowler Hat Sign-cup-shaped filling defect seen on air contrast BE that represents polyp if it points toward lumen and tic if it points away

Black Pleural Line-paradoxical appearance of pleura in pulmonary microlithiasis because of innumerable dense calcifications in adjacent lung

Bird of Prey Sign-tapered barium column in sigmoid volvulus; Bird's beak sign in achalasia

Boot-shaped Heart-shape of heart in Tetralogy of Fallot due to upturned apex from RVH and concave pulmonary artery segment

Bowtie Appearance-of facets in the cervical spine on lateral view in unilateral rotatory subluxation at and above the site of rotation

Bamboo Spine-undulating contour of spine caused by bridging syndesmophytes seen in ankylosing spondylitis

Bucket Handle Tear-vertical tear in knee of mostly medial meniscus with displacement of fragment toward notch

Butterfly Vertebra-congenital sagittal cleft through center of vertebra with funnel-shaped ends on AP view of spine

Bone-within-a-Bone-inner layer of cortical new bone within an existing bone seen with osteopetrosis, Sickle Cell Dz, Thorotrast

Breast-within-a-Breast-in fibroadenolipoma / hamartoma of breast; benign proliferation of normal breast components – fibrous, glandular, and fatty tissues – are surrounded by a thin capsule of connective tissue

Bear Paw Sign-dilated renal calyces with normal renal pelvis seen in calculus disease and

xanthogranulomatous pyelonephritis

Boutonniere Deformity-hyperextension of distal interphalangeal joint and flexion of proximal interphalangeal joint in RA

Brim Sign-thickening of the iliopectineal line (pelvic brim) in Paget's disease

Boomerang Sign-hyperintense signal in the splenium of the corpus callosum accompanying stroke; also an MRI sign in peroneus brevis split syndrome

Box-shaped Heart-squared-off appearance of the heart in Ebstein's Anomaly due to large right atrium and dilated right ventricular outflow tract

Bite Sign-MSK-gouged-out defect due to collapse of bone in head of femur in avascular necrosis

Bulging Fissure Sign-bulging of usually minor fissure from heavy,exudative pneumonia like Klebsiella

Banana Sign-abnormal shape of the cerebellum from compression seen on MRI or antenatal US in spina bifida and other neural tube defects