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20 results found

Waldenström sign (hip)

Waldenström sign is the increased distance between the pelvic tear drop and the femoral head. It is a non-specific sign of hip joint effusion. Radiographic features Radiograph >11 mm total distance or >2 mm difference compared to contralateral hip 1, 2 measured between the lateral aspect of ...

Walking man sign (chest x-ray)

The walking man sign is seen on a lateral chest radiograph and is a sign of left atrial enlargement. It results from posterior displacement of the left main bronchus such that it no longer overlaps the right bronchus. The left and right bronchus thus appear as an inverted 'V', mimicking the legs...

Wasp-waist sign (spine)

The wasp-waist sign is a radiographic appearance seen in patients with Klippel Feil syndrome. It results from fusion of the vertebral bodies such that the anteroposterior diameter at the level of the affected discovertebral joint is smaller than the diameter at the superior and inferior limits o...

Water bottle sign (heart)

The water bottle sign or configuration refers to the shape of the cardiac silhouette on erect frontal chest x-rays in patients who have a very large pericardial effusion. Typically the effusion has accumulated over many weeks to months (e.g. in patients with malignancy) and the pericardium has g...

Water-lily sign (liver)

The water-lily sign is seen in hydatid infections when there is detachment of the endocyst membrane which results in floating membranes within the pericyst that mimic the appearance of a water lily. It is classically described on plain radiographs (mainly chest X-ray) when the collapsed membran...

Wave sign

The wave sign refers to the indentation of the normal thymus in young children by the ribs, resulting in a wavy border.

Weapon and munition inspired signs

Weapon and munition inspired signs include the following with their corresponding pathologic conditions: bayonet deformity Turner syndrome chondrodysplasia bullet-shaped vertebra ​mucopolysaccharidosis achondroplasia cannonball metastases ​metastases from renal cell carcinoma dagger sig...

Westermark sign (lungs)

Westermark sign is a sign of pulmonary embolus (PE) seen on chest radiographs. Along with Fleishner sign and Hampton hump, it makes one of the three described signs of pulmonary embolus on chest radiographs. Pathology In one study (PIOPED) this sign was present on ~10% of chest x-rays of pati...

Wheels within wheels sign

This sign is seen in USG of patient with the hepatic candidiasis and described as central hypoechoic area (necrosis containing fungi) surrounded by an echogenic zone (inflammatory cells). Differs from bull’s-eye sign for reverse echogeniticity, as it consists a central echogenic nidus surrounde...

Whirlpool sign

The whirlpool sign, also known as the whirl sign, is seen when a structure twists upon itself. It is most commonly described in the abdomen where bowel rotates around its mesentery, with mesenteric vessels creating the whirls. It can also be seen in ovarian torsion. Whirlpool sign: mesenteric ...

White cerebellum sign

White cerebellum sign, also called reversal sign or dense cerebellum sign, is encountered when there is a diffuse decrease in density of the supratentorial brain parenchyma, with relatively increased attenuation of the thalami, brainstem and cerebellum. This sign indicates irreversible brain dam...

White matter buckling sign

The white matter buckling sign is helpful in distinguishing an extra-axial mass from an intra-axial one, and represents the white matter projecting into gyri being compressed and displaced by the mass, even in the presence of oedema (which would usually expand gyri, if the mass were intra-axial)...

White pyramid sign (kidney)

The white pyramid sign refers to the CT appearance of the medullary pyramids of the kidney which can be seen normally on unenhanced CT scans as high-attenuation triangular structures.  Bilateral high-attenuation renal pyramids are an occasional incidental normal finding.  In contrast, unilatera...

Widened intercondylar notch

A widened intercondylar notch on knee radiographs is a sign associated with: haemophilic arthropathy (most commonly bilateral) juvenile rheumatoid arthritis (most commonly bilateral) tuberculosis arthropathy (usually unilateral) (3)

Widow's peak hair anomaly

Widow's peak hair anomaly refers to a frontal hairline projection. Clinical features Prominent V shaped hairline projection. Ocular hypertelorism might be noted. On examination a bony prominence may be present. Pathology It is purported that the periorbital fields of hairless region or hairg...

Wimberger ring sign

Wimberger ring sign refers to a circular calcification surrounding the osteoporotic epiphyseal center of ossification in scurvy, which may result from bleeding. It must not be confused with Wimberger sign, pathognomonic of congenital syphilis.

Wimberger sign

The Wimberger sign, also called Wimberger corner sign, refers to localised bilateral metaphyseal destruction of the medial proximal tibias. It is a pathognomonic sign for congenital syphilis. It must not be confused with Wimberger ring sign seen in scurvy, which is sometimes also referred to as...

Windsock sign (aortic dissection)

The windsock sign refers to appearances seen in type A thoracic aortic dissections on contrast CT. It results from intimo-intimal intussusception between the true and false dissected lumens of the thoracic aorta. The altering density of contrast between the dissection lumens which taper distally...

Windsock sign (duodenal web)

The windsock sign is a typical appearance of a duodenal web (intraluminal duodenal diverticulum) on upper gastrointestinal contrast series which consists of an intraduodenal barium-contrast filled sac that is surrounded by a narrow lucent line (web or intraluminal mucosal diaphragm) which is wel...

Winking owl sign (spine)

The (absent) pedicle sign, also called the winking owl sign, occurs on plain film when a pedicle is absent. The term, winking owl sign, where the missing pedicle corresponds to the closed eye, the contralateral pedicle to the other open eye, and the spinous process to the beak of the animal on ...

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