CT colonography: accuracy of initial interpretation by radiographers in routine clinical practice.
ABSTRACT To investigate performance of computed-assisted detection (CAD)-assisted radiographers interpreting computed tomography colonography (CTC) in routine practice.
Three hundred and three consecutive symptomatic patients underwent CTC. Examinations were double-read by trained radiographers using primary two-dimensional/three-dimensional (2D/3D) analysis supplemented by "second reader" CAD. Radiographers recorded colonic neoplasia, interpretation times, and patient management strategy code (S0, inadequate; S1, normal; S2, 6-9 mm polyp; S3, > or = 10 mm polyp; S4, cancer; S5, diverticular stricture) for each examination. Strategies were compared to the reference standard using kappa statistic, interpretation times using paired t-test, learning curves using logistic regression and Pearson's correlation coefficient.
Of 303 examinations, 69 (23%) were abnormal. CAD-assisted radiographers detected 17/17 (100%) cancers, 21/28 (72%) polyps > or = 10 mm and 42/60 (70%) 6-9 mm polyps. The overall agreement between radiographers and the reference management strategy was good (kappa 0.72; CI: 0.65, 0.78) with agreement for S1 strategy in 189/211 (90%) exams; S2 in 19/27 (70%); S3 in 12/19 (63%); S4 in 17/17 (100%); S5 in 5/6 (83%). The mean interpretation time was 17 min (SD = 11) compared with 8 min (SD = 3.5) for radiologists. There was no learning curve for recording correct strategies (OR 0.88; p = 0.12) but a significant reduction in interpretation times, mean 14 and 31 min (last/first 50 exams; -0.46; p < 0.001).
Routine CTC interpretation by radiographers is effective for initial triage of patients with cancer, but independent reporting is currently not recommended.
- SourceAvailable from: Augusto von Atzingen[Show abstract] [Hide abstract]
ABSTRACT: OBJECTIVES: The purpose of our study was to report the results of the implementation of computed tomography colonography in a university hospital setting serving a Brazilian population at high risk of colorectal cancer. METHODS: After creating a computed tomography colonography service in our institution, 85 patients at high risk of colorectal cancer underwent computed tomography colonography followed by a same-day optical colonoscopy from September 2010 to May 2012. The overall accuracy of computed tomography colonography in the detection of lesions ≥6 mm was compared to that of optical colonoscopy (direct comparison). All colonic segments were evaluated using quality imaging (amount of liquid and solid residual feces and luminal distension). To assess patient acceptance and preference, a questionnaire was completed before and after the computed tomography colonography and optical colonoscopy. Fisher's exact test was used to measure the correlations between colonic distension, discomfort during the exam, exam preference and interpretation confidence. RESULTS: Thirteen carcinomas and twenty-two lesions ≥6 mm were characterized. The sensitivity, specificity and accuracy of computed tomography colonography were 100%, 98.2% and 98.6%, respectively. Computed tomography colonography was the preferred method of investigation for 85% of patients. The preparation was reported to cause only mild discomfort for 97.6% of patients. According to the questionnaires, there was no significant relationship between colonic distension and discomfort (p>0.05). Most patients (89%) achieved excellent bowel preparation. There was a statistically significant correlation between the confidence perceived in reading the computed tomography colonography and the quality of the preparation in each colonic segment (p≤0.001). The average effective radiation dose per exam was 7.8 mSv.Clinics 12/2014; 69(11):723-730. · 1.42 Impact Factor
- Frontline Gastroenterology. 03/2011; 2(2):96-104.
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ABSTRACT: Aim: To critically assess the evidence base to help establish the most desirable role for computed tomographic colonography (CTC) in bowel cancer screening. Introduction: Bowel cancer develops over time from polyps. Early detection improves outcomes of this major health problem, so a targeted UK screening programme has been introduced. Currently, faecal occult blood test is followed by optical colonoscopy (OC) in positive cases. CTC is currently only used where OC is contraindicated or incomplete. The optimum role for CTC in screening is controversial. The ongoing debate must consider a range of factors in the context of the screening scenario and in light of evolving CTC protocols and guidance. Findings: Diagnostic ability: CTC’s sensitivity is more variable and lower than OC, but technological improvements such as computer-aided detection (CAD) and better understanding of optimal technique promise improved results. There remain uncertainties around surveillance periods, clinically-significant lesion size, and the cost of extra-colonic findings. The linkages between these factors are unclear. Furthermore, many findings are based on populations that are not necessarily transferable to the screening situation. Risks: CTC involves radiation, but the risk is considered low, especially in a screening population. Technological advances promise further dose reductions. Perforation and the use of contrast agents may also present small risks. Patient acceptability: CTC is generally considered less unpleasant than OC, but patient acceptability may still be lower in a secondary screening role. Availability & cost: CTC may be cost-effective in primary screening, but expanding capacity is slow and expensive. The likely cost of investigating and treating extra-colonic findings is unclear. Conclusions: CTC is a new technique which, though promising, still has many uncertainties which are interlinked. It is currently difficult to determine the most desirable screening role, especially as bowel cancer screening itself is still new and evolving. Further research specific to the screening scenario is required.Radiography 08/2013; 19(3):246-250.