proctosigmoidoscope

medical instrument

Also known as: sigmoidoscope

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Last updated

July 13, 2026

Quick Summary

A proctosigmoidoscope is a flexible, fiber-optic endoscope used in a medical procedure called a sigmoidoscopy. This instrument allows doctors to examine the rectum and the lower part of the large intestine, known as the sigmoid colon.1

The sigmoidoscope contains a light source and channels for air, water, and suction. It can also be used to insert instruments for procedures like taking biopsy samples. Its flexibility makes it more comfortable for patients than older, rigid scopes.1

Sigmoidoscopy is crucial for the early detection of colorectal cancer by identifying and removing precancerous polyps.1

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colorectal cancer
Diagnosis
…narrow, flexible tube called a sigmoidoscope to look at the lining of the rectum and the end of the colon. Colonoscopy uses a similar device to examine the entire colon. A biopsy may also be conducted in which abnormal tissue is removed by using the colonoscope and then examined under…
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…narrow, flexible tube called a sigmoidoscope to look at the lining of the rectum and the end of the colon. Colonoscopy uses a similar device to examine the entire colon. A biopsy may also be conducted in which abnormal tissue is removed by using the colonoscope and then examined under…
Read More

sigmoidoscopy
…flexible 60-cm endoscope called a sigmoidoscope. This instrument consists of a bundle of optical fibres that carry the visual image; it can be bent at the tip in four directions by means of controls at the base so that it can be maneuvered through the contorted sigmoid colon. The scope…
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…flexible 60-cm endoscope called a sigmoidoscope. This instrument consists of a bundle of optical fibres that carry the visual image; it can be bent at the tip in four directions by means of controls at the base so that it can be maneuvered through the contorted sigmoid colon. The scope…
Read More

endoscopy
…of the colon, and the proctosigmoidoscope, a similar instrument used for examination of the rectum and lower colon, are passed through the anal orifice; mild sedation and pain medication are typically administered during these procedures. The cystoscope, a lighted rod, is passed through the urethra for examination of the bladder…
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…of the colon, and the proctosigmoidoscope, a similar instrument used for examination of the rectum and lower colon, are passed through the anal orifice; mild sedation and pain medication are typically administered during these procedures. The cystoscope, a lighted rod, is passed through the urethra for examination of the bladder…
Read More