Brief Article
Copyright ©2012 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Apr 21, 2012; 18(15): 1789-1792
Published online Apr 21, 2012. doi: 10.3748/wjg.v18.i15.1789
Prospective controlled study on the effects of polyethylene glycol in capsule endoscopy
Takafumi Ito, Ken Ohata, Akiko Ono, Hideyuki Chiba, Yosuke Tsuji, Hajime Sato, Nobuyuki Matsuhashi
Takafumi Ito, Ken Ohata, Akiko Ono, Hideyuki Chiba, Yosuke Tsuji, Nobuyuki Matsuhashi, Department of Gastroenterology, Kanto Medical Center, NTT East, Tokyo 1418625, Japan
Hajime Sato, Department of Health Policy and Technology Assessment, National Institute of Public Health, 2-3-6 Minami, Wako-shi 3293147, Japan
Author contributions: Ito T was the main author; Ohata K, Ono A, Chiba H and Tsuji Y contributed to the data acquisition; Sato H performed the statistical analysis; and Matsuhashi N designed the study and edited the manuscript.
Correspondence to: Nobuyuki Matsuhashi, MD, Department of Gastroenterology, Kanto Medical Center, NTT East, 5-9-22 Higashi-gotanda, Shinagawa-ku, Tokyo 1418625, Japan. nmatuha-tky@umin.ac.jp
Telephone: +81-3-34486245 Fax: +81-3-34486248
Received: August 3, 2011
Revised: September 14, 2011
Accepted: February 26, 2012
Published online: April 21, 2012
Abstract

AIM: To prospectively confirm whether a small amount of polyethylene glycol (PEG) ingested after swallowing endoscopy capsule improves image quality and completion rate.

METHODS: Forty-four consecutive patients referred to us for capsule endoscopy (CE) were randomized to two groups. All patients were restricted to clear fluids for 12 h before the examination. Patients in group A (22 cases) received no additional preparation, while those in group B (20 cases) ingested 500 mL of PEG within a 2 h period starting 30 min after swallowing the capsule. Clear fluids and meals were allowed 2 h and 4 h after capsule ingestion, respectively. Image quality was assessed as the percentage of visualized bowel surface area as follows: 1: < 25%; 2: 25%-49%; 3: 50%-74%; 4: 75%-89%; 5: > 90%. The small bowel record was divided into five segments by time, and the score for each segment was evaluated. All CE examinations were performed with the Pillcam SB capsule endoscopy system (Given Imaging Co. Ltd., Yoqnem).

RESULTS: This study ended in December 2009, because sample size was considered large enough. A total of 44 patients were enrolled. Two patients in group B were excluded from the analysis because small bowel images could not be obtained from these patients; one had a full stomach, while the other presented with a massive gastric bleed. Thus, 22 patients from group A and 20 patients from group B completed the study. There was no significant difference in age (P = 0.22), sex (P = 0.31), and indication for CE. No significant adverse events occurred in any of the study patients. In group A, image quality deteriorated as the capsule progressed distally. However, in group B, image quality was maintained to the distal small bowel. In each of the five segments, the visibility score was significantly higher in group B than in group A (segment 1: 4.3 ± 0.7 vs 4.7 ± 0.5, P = 0.03; segment 2: 4.2 ± 0.9 vs 4.8 ± 0.4, P = 0.01; segment 3: 4.0 ± 1.0 vs 4.6 ± 0.7, P = 0.04; segment 4: 3.6 ± 1.1 vs 4.5 ± 0.6, P = 0.003; segment 5: 2.7 ± 1.0 vs 4.4 ± 0.8, P = 0.00004). Thus, the use of PEG during CE examination significantly improved image quality in all time segments, and this effect was more pronounced in the distal ileum. The completion rate to the cecum was not significantly different between groups A and B (81.8% vs 85.0%, P = 0.89). There was no difference in the gastric transit time between groups (36.2 ± 35.0 min vs 54.0 ± 56.6 min, P = 0.23), but the small bowel transit time was significantly longer in group A than in group B (246.0 ± 107.0 min vs 171.0 ± 104.0 min, P = 0.04).

CONCLUSION: The ingestion of a small amount of PEG after the swallowing of an endoscopy capsule significantly improved CE image quality, but did not enhance the completion rate to the cecum.

Keywords: Capsule endoscopy; Completion rate; Image quality; Polyethylene glycol; Preparation