Colonoscopy

What it does

Colonoscopy reads a recorded procedure after it has ended: a full screening or surveillance video, clips, or a set of stills. It documents the quality indicators that are usually estimated by hand and lists every polyp seen during withdrawal, each with its own evidence frame and timestamp.

The result shows whether the caecum was reached (appendiceal orifice, ileocaecal valve, terminal ileum, with evidence frames), the withdrawal time net of interventions, and the Boston Bowel Preparation Scale per segment. Each polyp is tracked across frames and reported once, with location, estimated size, Paris morphology, NICE or JNET class and predicted histology. In ulcerative colitis the run scores endoscopic activity per segment.

Intended use

Decision support after the procedure: a second look at the recording, an automatically documented quality report and a structured polyp list for the endoscopy report. The surveillance interval in the guidance is marked "pending histology" until pathology is back.

Who it is for

Gastroenterologists, colorectal surgeons, nurse endoscopists, trainees learning withdrawal technique, and screening programmes auditing adenoma detection. Developers call the run to add colonoscopy quality metrics to an endoscopy reporting system or registry.

Accepted input

• Video: MP4, MOV or MKV (H.264/H.265), or DICOM Video Endoscopic Image; a full 15–40 minute procedure or shorter clips.
• Stills: JPEG/PNG sets or DICOM VL Endoscopic Image.
• Light modes: white light, NBI, BLI, LCI and i-scan are recognised; scope model and light mode are read from metadata when present.

Requirements

Requirement	Why
Whole withdrawal recorded	Withdrawal time and BBPS per segment need the full withdrawal phase
Caecal landmarks in view	Caecal intubation is documented only from evidence frames
Frame rate in the file	Timestamps and withdrawal time depend on it
Open forceps or snare beside a polyp	Polyp size from video is an estimate; a reference object improves it
NBI or similar mode on polyps	Narrow-band classes (NICE, JNET) need image-enhanced views

Optional context

Indication (screening, surveillance, symptoms, IBD), prior polyps and the last colonoscopy date can be passed in clinical_context for the surveillance guidance.

The result

Section	Content
Caecal landmarks	Appendiceal orifice, ileocaecal valve, terminal ileum and retroflexion, with evidence frames
Withdrawal time	Withdrawal time net of interventions, segment timeline and an inspection-quality score
Bowel preparation (BBPS)	BBPS 0–3 for right, transverse and left colon, total score and adequacy
Polyp detection	Tracked polyps with boxes or masks, count, key frames and first and last timestamps
Polyp characterisation	Adenoma versus non-adenoma, NICE/JNET class, Paris type, size estimate and PIVI eligibility
Ulcerative colitis activity	Mayo endoscopic subscore 0–3 and UCEIS per segment
Draft report	Opt-in (options.report): an English narrative that interprets the result for the reader (findings, impression, limitations); every number is checked against the findings

Standards

• Terminology: WEO Minimal Standard Terminology (MST 3.0).
• Quality: ESGE colonoscopy performance measures and ASGE/ACG quality indicators (caecal intubation, adenoma detection, withdrawal time).
• Lesions: Paris classification of superficial neoplastic lesions; NICE and JNET narrow-band-imaging classifications; ASGE PIVI thresholds for "resect and discard" and "diagnose and leave".
• Surveillance: USMSTF 2020 and ESGE 2020 post-polypectomy surveillance.
• DICOM and FHIR: key frames as VL Endoscopic Image, annotated clips as Video Endoscopic Image, key-frame selection as KOS, masks as Segmentation, scores and size estimates in SR TID 1500; FHIR R4 Procedure, DiagnosticReport and Observation.

Works with

Colorectal Pathology (path/colorectal) reads the resected polyps, so the optical diagnosis can be audited against histology.