Skip to main content
Detailed chapter

The Colonoscopy Procedure

Diagnostic exam, therapeutic polypectomy, sedation, duration

Under sedation, a flexible colonoscope examines the entire colon. Polyps may be removed and biopsies taken in the same session. Selected cases may also need colonic stenting, decompression for obstruction or volvulus, or balloon dilation for strictures.

Procedure · educational illustration

Outcomes of any surgical or interventional procedure may vary from person to person. Please seek a detailed consultation with your physician before any procedure.

© Cengiz Dibekoğlu — illustrative; not for unauthorized use

Figure summary

This educational figure shows: Procedure.

Key points

  • Diagnostic phase

    The endoscopist inspects the mucosa for polyps, inflammation, bleeding sources, and tumors. Cecal intubation marks a complete examination.

  • Therapeutic phase

    Polypectomy with a snare, biopsy, bleeding control (clips, injection), colonic stent for selected obstruction or malignant stricture, decompression when the colon is distended or obstructed, and balloon dilation for benign strictures can be done during the same procedure. Large polyps may be removed piecemeal (EMR).

    • Polypectomy — most common therapeutic step; pathology required
    • Stent and decompression — selected obstruction/volvulus cases
    • Balloon dilation — stricture; bleeding control — active bleeding
    • Therapeutic steps extend procedure time and may increase complication risk
  • Pain and duration

    With sedation, pain is uncommon. Scope time is often 20–45 minutes; total visit 2–4 hours including recovery.

  • Risks

    Key note inside

    Bleeding and perforation are uncommon but serious — especially after large polypectomy. Heavy bleeding or severe pain needs urgent review.

This page is for education. It is not medical advice and does not replace a visit with your physician.

Medical editor: Assoc. Prof. Cengiz Dibekoğlu, MD · Last medically reviewed: August 2026 · English patient-education chapter.