Seigo Igarashi

Pudendal Nerve Terminal Motor Latency in Patients With or Without Soiling 5 Years or more after Low Anterior Resection for Lower Rectal Cancer

BackgroundTo clarify the neurological function with respect to external anal sphincter (EAS) muscles in patients with or without soiling after low anterior resection (LAR) for lower rectal cancer, we examined the terminal motor latency in the pudendal motor nerves (PNTML).Materials and MethodsThirty-eight patients after LAR for lower rectal cancer were studied electrophysiologically and compared with 30 healthy volunteers as controls (19 men and 11 women, aged 44 to 76 years of age, with a mean age of 65.5 years). Patients after LAR were divided into two groups [18 patients with soiling (12 men and 6 women, aged 51 to 77 years with a mean age of 64.8 years), 20 patients without soiling (13 men and 7 women, aged 47 to 75 years with a mean age of 62.1 years)]. The mean follow-up time from LAR was 67.2 months (range 60–84 months). Bilateral (left-sided and right-sided) PNTML tests were performed on all patients in order to measure the latency of the response in the bilateral EAS muscle following digitally directed transrectal pudendal nerve stimulation.ResultsThe distance from the anal verge to the level of anastomosis in patients with soiling (mean, 2.2 cm) was significantly shorter than that in patients without soiling (mean, 4.1 cm) (P < 0.05). Conduction delay of the bilateral PNTML in patients with soiling was longer than that in patients without soiling and normal subjects, significantly (P < 0.01, respectively). There was no significant difference between the right-sided and left-sided PNTML.ConclusionsThese findings support the hypothesis that soiling after LAR may be partially caused by damage to the bilateral pudendal motor nerves.

Study of segmental colonic transit time in healthy men.

BACKGROUND/AIMS There are few reports of the segmental colonic transit time (SCTT) in healthy men. To clarify the SCTT for healthy men, the author measured the SCTT of healty men using radiopaque markers (RM). METHODOLOGY The author analyzed the SCTT of 26 healthy men, who were aged from 24 to 60 years and had a mean age of 48.8 years, with RM (20 radiopaque polyvinyl chloride 0-rings). The criteria for participation included a usual stool frequency of between three per week and three per day, no history of gastrointestinal disease, and no use of medications known to affect gastrointestinal motility. RESULTS The overall gastrointestinal transit time was 36.2±5.1 hours, and the transit time from the mouth to the cecum was 6.8±1.4 hours. The half-dose transit times of the ileocecal valve, hepatic flexure, splenic flexure, descending-sigmoid line, and evacuation were 6.9±1.6, 15.9±1.7, 18.8±1.7, 24.3±4.4 and 36.4±5.3 hours, respectively. The ascending (9.5±2.3 hours) and descending colon (5.5±4.1 hours) had shorter transit times than the sigmoid-rectum section (12.7±2.1 hours) (p<0.001, p<0.01, respectively), and the transverse colon (4.2±2.1 hours) had a shorter transit time than the ascending colon (p<0.05). There were no significant differences in transit time between the descending and transverse colon. CONCLUSIONS Measuring the SCTT using RM may be effective for detecting the SCTT of specific sections of the bowel. This method is simple and can be easily performed at any radiology department.