doughnut sign

GI endoscopy See Bull’s-eye sign
Imaging—Heart A descriptor for the radionuclide image of a large anterior wall MI, in which there is decreased uptake of 99mTc stannous pyrophospate in the central infarcted zone; the zone is surrounded by a region of intermediate uptake; it is seen in larger infarcts and is associated with a poor prognosis
Imaging—Intestine Pseudokidney sign The term refers to the circumferential thickening of the bowel wall in a CT, caused by primary colon cancer, inflammatory bowel disease, and intussusception—which is also known as the target or bull’s-eye sign
Imaging—Lungs A circumscribed mass/coin lesion with a central, rounded hypodense area seen on plain AP films, which usually corresponds to central tumour necrosis, often associated with bronchogenic carcinoma. The doughnut sign may be seen in abscesses, which often have a fluid level
Imaging—Testis A finding in scintigraphy of subacute testicular torsion in which preserved dartos perfusion creates a halo of radiotracer uptake surrounding the scintipenic testicle

doughnut sign

Imaging A descriptor for the radionuclide image of a large anterior wall MI, in which there is ↓ uptake of 99mTc stannous pyrophospate in the central infarcted zone; the zone is surrounded by a region of intermediate uptake; it is seen in larger infarcts and is associated with a poor prognosis. See Acute MI.

donut sign

, doughnut signOne of several radiologic findings in which a halo surrounding an apparently empty space is present. It is seen, e.g., (a) on chest x-rays of hilar lymphadenopathy, when lymph nodes surround a bronchus; (b) in abdominal imaging, when a thickened bowel wall surrounds the intestinal lumen or an intussusception; and (c) in bone scans, when a rim of tracer uptake surrounds a "cold" center.