Magnetic Resonance Imaging of Morphological and Functional Changes of the Uterus Induced by Sacral Surface Electrical Stimulation

Abstract

The purpose of this study is to examine the morphological and kinematical changes of the uterus induced by electrical stimulation applied to the skin just above the second and fourth posterior sacral foramens (sacral surface electrical stimulation [ssES]) in 26 healthy subjects. Out of them, eight subjects who had severe pain subjectively during every menstruation received ssES just in menstruation. Morphological and functional changes of the uterus were examined by using T2-weighted magnetic resonance (MR) imaging and T1-weighted MR cinematography, respectively. Cyclic electrical stimulation for 15 min with 5 sec ON and 5 sec OFF was applied just before MR scanning. A decrease in thickness of the muscular layer of the uterus was observed in every subject after ssES for 15 min and was significant as compared with the thickness before ssES. Periodic uterine movement during menstruation was observed in the subjects with severe menstrual pain in MR cine and the power spectrum analysis of the movement showed a marked decrease in peak power and frequency after ssES treatment. We conclude that ssES causes a reduction of static muscle tension of the uterus in all menstrual cycle periods and suppression of uterine peristalsis during menstruation in the subjects with severe menstrual pain. Possible neural mechanisms for these static and dynamic effects of ssES on the uterus at spinal level are discussed.sacral surface electrical stimulation; uterus; MRI; neuromodulation © 2006 Tohoku University Medical PressThe contractile component of the uterine wall is the myometrium which is composed of smooth muscles. The myometrium regulates tension of the uterine wall and peristaltic movements of the uterus under control of the autonomic nervous system. The pelvic organs are controlled by the hypogastric nerves (sympathetic) and pelvic nerves (parasympathetic) which are, in general,

Uterine relaxation by sacral surface electrical stimulation on the day of embryo transfer

“…It was recently demonstrated that uterine peristalsis during menstruation can be suppressed by sacral surface electrical stimulation (ssES), the application of electrical stimulation to the skin above the second and fourth posterior sacral foramen (8). Our study investigated the effect of ssES on uterine relaxation on the day of ET.…”

“…The details of ssES have been described previously elsewhere (8). We recorded images obtained by transvaginal ultrasonographic imaging before and after ssES for 3 minutes, after which a physician performed the ET.…”

“…Image analysis was performed using Ogura's method with modifications (8). The region of interest (ROI), which did not exceed the uterine diameter, was fixed at the center of the uterine body adjacent to the internal cervical os.…”

The Effect of sacral nerve stimulation on uterine activity: a pilot study

“…It seems plausible that, in case of an SNS implant with an electrode in the 3rd or 4th sacral foramen, uterine innervation might also be influenced by this stimulation. MRI investigations have shown that sacral surface electrical stimulation just above the second and fourth posterior sacral foramen causes reduction of static muscle tension [10].…”

Analgesia by sacral surface electrical stimulation for primary dysmenorrhoea

“…attached to the skin directly above the second and fourth sacral foramina (12,13). For dysmenorrhoea, this has been reported to reduce the thickness of the uterine muscle layer and suppress peristaltic movement (12). However, there are no reports regarding the effects of sacral surface electrical stimulation on pain.…”