Transabdominal Functional Magnetic Stimulation for the Treatment of Constipation in Brain-Injured Patients: A Randomized Controlled Trial

Abstract

Objective: To investigate the effects of the transabdominal functional magnetic stimulation (A-FMS) for constipation in stroke or brain-injured patients.

Methods: Twenty-four brain-injured patients (11 males and 13 females; median age, 65 years; 22 cases of stroke and 2 cases of traumatic brain injury) with constipation, who were admitted to the rehabilitation department, were enrolled and randomly divided into magnetic stimulation (MS) group and sham stimulation (Sham) group. Several parameters related with constipation such as total and segmental colon transit time (CTT), defecation frequency, and Bristol Stool Scale (BSS) before and after 2 weeks of A-FMS (5 times per week, total 10 times of A-FMS) were evaluated. The Korean version of the Modified Barthel Index (K-MBI) was also evaluated.

Results: A significant decrease in segmental CTT in the left colon (-8.2±3.9 vs. 4.1±2.5 hours; p<0.05 by paired sample t-test) and a significant increase in the frequency of defecation (1.5±0.2 vs 0.7±0.3; p<0.05 by paired sample t-test) were observed in the MS group compared with the Sham group. Stool hardness became significantly softer in the MS group compared with the Sham group (2.3-3.5 in the MS and 2.6-3.1 in the Sham; p<0.05 by chi-square test) as evaluated by BSS. No difference in the K-MBI was observed between the two groups.

Conclusion: The present study suggests that A-FMS can be an additional therapeutic tool for managing constipation in brain-injured patients with abnormal bowel movement, defecation frequency, and stool hardness.

Keywords: Brain injuries; Constipation; Magnetic stimulation; Stroke; Traumatic brain injuries.

Fig. 1.

Simple abdomen radiographs show (A) three segments of the colon (right, left, and rectosigmoid colon) and distribution of radiopacity markers (arrows), and (B) before and (C) after 2 weeks of transabdominal functional magnetic stimulation. Three segments were divided with imaginary lines starting from the spinous process of a 5th lumbar vertebra to the upper spinous processes, to passing the right pelvic outlet, and to passing the left iliac crest. To calculate the colon transit time, the number of remaining radiopacity markers were counted and multiplied by 1.2 [15].

Fig. 2.

Transabdominal functional magnetic stimulation is applied in an experimental patient (A) and sham stimulation in control patient (B). In (B), note that the magnetic head is 5 cm apart from the patient’s belly and the stimulation intensity is 30% of the maximal intensity (1.5 T) so that the patient hears stimulation sound but does not feel the magnetic stimulation.

Fig. 3.

Comparison of colon transit time (CTT) between transabdominal functional magnetic stimulation group (MS) and sham stimulation group (Sham): (A) total CTT, (B) right colon CTT, (C) left colon CTT, and (D) rectosigmoid CTT. PRE, pre-treatment; POST, post-treatment. *p<0.05 by Student t-test.