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1,131 results found

Whipple disease (gastrointestinal manifestations)

Gastrointestinal manifestations are a key component of Whipple disease.  The gastrointestinal manifestations of Tropheryma whipplei are also known as intestinal lipodystrophy. Pathology Extensive infiltration of the lamina propria with large macrophages infected by intracellular T. whipplei ca...

Whipple procedure

The Whipple procedure (or partial pancreaticoduodenectomy) is considered the definitive surgical operation to resect carcinoma of the head of the pancreas, periampullary carcinoma, or duodenal carcinoma 1. Procedure In the procedure, the head of the pancreas and adjacent duodenum is resected. ...

Whipple triad

Whipple triad is the clinical presentation of pancreatic insulinoma and consists of: fasting hypoglycemia (<50 mg/dL) symptoms of hypoglycemia immediate relief of symptoms after the administration of IV glucose History and etymology The triad and also the Whipple procedure were both named a...

Whirlpool sign (mesentery)

The whirlpool sign of the mesentery, also known as the whirl sign, is seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.  Terminology The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation). Radiographic features It is...

WHO classification of anal canal tumors

The World Health Organization classifies anal canal neoplasms into intraepithelial neoplasms and invasive neoplasms which are further divided to epithelial and non-epithelial tumors and secondary lesions: Epithelial tumors squamous cell carcinoma of anal canal adenocarcinoma of anal canal mu...

WHO classification of anal margin tumors

The WHO classification of anal margin tumors or perianal skin tumors is: intraepithelial tumors Bowen disease (precursor of squamous cell carcinoma) Paget's disease (precursor of adenocarcinoma) invasive tumors squamous cell carcinoma adenocarcinoma basal cell carcinoma  verrucous carcin...

Widening of the presacral space (differential)

Widening of the presacral space is one of the diagnostic indicators of the diseases involving pelvic pathology and rectal involvement. It is ideally measured on barium studies at the level of S3/4 disc level on lateral radiographs and the normal value of the presacral space is <15 mm in adults.​...

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...

Wound dehiscence

Wound dehiscence is a surgical complication whereby there is rupture of a wound along the surgical scar (dehiscence, refers to "splitting open"). This may occur on the skin surface, or along a deeper suture line. Clinical presentation Presentation may be with pain (e.g. sternal dehiscence), or...

X-marks-the-spot sign (large bowel volvulus)

The X-marks-the-spot is a sign of complete bowel volvulus and refers to the crossing loops of the bowel at the site of the transition. It has been reported to improve diagnostic confidence in detecting cecal and sigmoid volvulus. This is in contrast to the split-wall sign which indicates partial...

Zebra spleen

Zebra spleen, also referred to as psychedelic spleen or more correctly inhomogeneous splenic enhancement, refers to the transient heterogeneous parenchymal enhancement of the spleen during the arterial or early portal venous phases of contrast enhancement in CT, MRI, or ultrasound imaging. It i...

Zenker diverticulum

Zenker diverticulum, also known as a pharyngeal pouch, is a posterior outpouching of the hypopharynx, just proximal to the upper esophageal sphincter through a weakness in the muscle layer called the Killian dehiscence. Epidemiology More than 50% of the affected patients present in 60-80 years...

Zinc toxicity

Zinc toxicity (also rarely known as zincalism) is rare as the body is remarkably efficient at excreting excess zinc. Typically oral zinc poisoning manifests primarily as: acute GI symptoms: vomiting, diarrhea, abdominal pain secondary copper deficiency zinc competes with copper for absorption...

Zollinger-Ellison syndrome

Zollinger-Ellison syndrome (ZES) is a clinical syndrome that occurs secondary to a gastrinoma.  Clinical presentation Diagnosis of ZES is often delayed by 5-7 years after the onset of symptoms 2.  Pathology Gastrinomas are usually multiple and typically located in the duodenum (more common) ...

Zuelzer-Wilson syndrome

Zuelzer-Wilson syndrome, also known as total colonic aganglionosis, is a subset of Hirschsprung disease, in which the whole colon is aganglionic. Epidemiology It is uncommon and accounts for 2-13% of cases of Hirschsprung disease 3,7. Compared with Hirschsprung disease which has a marked male ...

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