Background:
Colonoscopy stands out as the sole modality offering comprehensive visualization of the colon, coupled with the potential for therapeutic intervention. Nevertheless, achieving cecal intubation is not universally feasible, particularly in cases of a redundant or angulated colon. The failure to attain complete colonoscopy heightens the risk of subsequent proximal colon cancer following the procedure. The recommended national benchmark for cecal intubation is 90%. Often, in instances of unsuccessful cecal intubation, the alternative approaches of barium enema or CT colonography are pursued instead of a repeat endoscopic assessment even though these alternatives do not provide direct visualization or the opportunity for therapeutic intervention.

Aim:
The aim of this pooled systematic review was to assess the outcomes of repeat colonoscopy after a previous incomplete procedure.

Methods:
A comprehensive literature search using 3 databases was conducted. We aimed to include studies with patients undergoing reattempt endoscopy after previous failed attempt unrelated to poor bowel preparation. Pooled rates were calculated for multiple variables as below with a 95% confidence interval (CI) and meta-regression was carried out with statistically significant p<0.05. Data was analyzed via OpenMeta analysis software.

Results:
A total of 27 studies involving 1705 patients (61% female) met inclusion criteria. The mean age of included patients was 61.9 (CI 60.43, 63.4). More than a third had history of previous abdominal (35%) or pelvic (25%) surgery. 54% (CI 0.42, 0.66) had documented failure of previous colonoscopy because of looping/redundant colon and 33% (CI 0.16, 0.50) had documented sharp angulation or stricturing diverticular disease. The pooled CIR on repeat attempt was 95% (IQR 0.94-0.96); with standard colonoscope CIR 94.7% (IQR 0.93-0.96), single balloon enteroscopy (SBE) CIR 96.5% (IQR 0.94-0.99) and double-balloon enteroscopy (DBE) CIR 94.5% (IQR 0.92-0.97) (Figure 1). Meta regression when controlled for variables including female gender and age did not reveal any significant covariates (p=0.66). In studies where results were reported, adenomas were detected in 36.5% of procedures and neoplasia was detected in 2.1% procedures (Figure 2).

Conclusion:
Our study underscores the significance of opting for a repeat attempt by a skilled endoscopist in cases of incomplete colonoscopy, rather than resorting to barium enema or CT colonography. This alternative approach yields a commendable CIR of 95%. Importantly, this also enables potential therapeutic intervention, particularly considering the substantial number of neoplasias and adenomas identified in our comprehensive pooled analysis.

Figure 1: Cecal intubation rates (CIR) grouped by type of endoscope used.

Figure 2: Number of adenomas detected in pooled analysis.

Muhammad Aziz

Appearances