Minute perforation after argon plasma coagulation for management of small colonic polyps.

month history of chronic constipation and abdominal bloating. Because of concern about a colorectal lesion, colonoscopy was done and hundreds of small polyps were found throughout the colon, most being less than 4mm in diameter. Some of the bigger polyps were removed by polypectomy andwere found at pathologic examination to be tubular adenoma. As the patient was unwilling to undergo a rectum-preserving total colectomy, argon plasma coagulation (APC) was selected to ablate the remaining polyps as far as possible (l" Fig. 1). APC was done using an Olympus system (PSD-60; Olympus, Tokyo, Japan) at settings of argon flow rate 1 l/minute, power 40W, effect 1. The patient tolerated the 1-hour procedure well until the end, when severe abdominal distension without rebound tenderness was noted. Because of the persistent abdominal discomfort, a standing chest radiograph was obtained which showed massive free air in the peritoneum (l" Fig. 2). Laparotomy was done immediately. The entire colon was checked carefully and a tiny perforation was found at the transverse colon (l" Fig. 3, arrow). After surgical closure of the perforation, the patient recovered uneventfully and was discharged 2 weeks later. APC is safe and effective for the management of gastrointestinal tract bleeding, polyp remnants, and watermelon stomach, ablation of precancerous lesions, and so on [1–3]. An asymptomatic air accumulation in the peritoneummay develop after APC because the high argon flow induces submucosal emphysema with a leakage of gas through the gastrointestinal tract wall. Conservative treatment is suggested for this situation [4]. As our patient underwent APC ablation of numerous colonic polyps, the air insufflation was prolonged, leading to severe pneumoperitoneum even though there was only a tiny perforation. Thus, it is very important to distinguish between the symptomatic ‘perforation’ and the asymptomatic ‘air accumulation’ as causes of pneumoperitoneum. Minute perforation after argon plasma coagulation for management of small colonic polyps