CT colonography without cathartic preparation: positive predictive value and patient experience in clinical practice
- First Online:
To determine the positive predictive value (PPV) for polyps ≥6 mm detected at CT colonography (CTC) performed without cathartic preparation, with low-dose iodine faecal tagging regimen and to evaluate patient experience.
1920 average-risk patients underwent CTC without cathartic preparation. Faecal tagging was performed by diatrizoate meglumine and diatrizoate sodium at a total dose of 60 ml (22.2 g of iodine).The standard interpretation method was primary 3D with 2D problem solving. We calculated per-patient and per-polyp PPV in relation to size and morphology. All colonic segments were evaluated for image quality (faecal tagging, amount of liquid and solid residual faeces and luminal distension). Patients completed a questionnaire before and after CTC to assess preparation and examination experience.
Per-polyp PPV for detected lesions of ≥6 mm, 6–9 mm, ≥10 mm and ≥30 mm were 94.3%, 93.1%, 94.7% and 98%, respectively. Per-polyp PPV, according to lesion morphology, was 94.6%, 97.3% and 85.1% for sessile, pedunculated and flat polyps, respectively. Per-patient PPV was 92.8%. Preparation without frank cathartics was reported to cause minimal discomfort by 78.9% of patients.
CTC without cathartic preparation and low-dose iodine faecal tagging may yield high PPVs for lesions ≥6 mm and is well accepted by patients.
• Computed tomographic colonography (CTC) without cathartic preparation is well accepted by patients
• Cathartic-free faecal tagging CTC yields high positive predictive values
• CTC without cathartic preparation could improve uptake of colorectal cancer screening
KeywordsCT-colonography Faecal tagging Patient acceptance Colorectal cancer Bowel preparation colorectal polyp Adenoma
- 2.Levin B, Lieberman DA, McFarland B et al (2008) Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. CA Cancer J Clin 58:130–160PubMedCrossRefGoogle Scholar
- 15.Buccicardi D, Grosso M, Caviglia I et al (2010) CT colonography: patient tolerance of laxative free fecal tagging regimen versus traditional cathartic cleansing. Abdom Imaging. doi:10.1007/s00261-010-9650-4