Smooth muscle fraction of the round ligament in women with pelvic organ prolapse: a computer-based morphometric analysis

Abstract

Our objective was to compare the collagen and muscle content of the round ligament of uteri in women with pelvic organ prolapse. We evaluated the tissue samples obtained from the round ligaments of 22 patients with uterine prolapse who underwent vaginal hysterectomy (group A, study) and from 26 patients with no pelvic relaxation in whom total abdominal hysterectomy was performed for benign reasons (group B, controls). Morphometric analysis was performed on histologic cross-sections of the round ligament. Sections from each sample were stained with hematoxylin and eosin and Masson's trichrome methods. A computer system was used for morphometric measurements. We used independent samples t-test or Mann-Whitney U test to investigate the difference between the two groups. It was found that the smooth muscle fraction of the round ligament in women with uterine prolapse was significantly decreased compared with that of healthy control subjects and concluded that decreased smooth muscle content may be an important pathogenetic factor in uterine prolapse.

Neuromuscular morphometry of the uterine ligaments and vaginal wall in women with pelvic organ prolapse

“…In the round ligament, a significantly decreased smooth muscle fraction was morphometrically measured in H&E and Masson's trichrome slides from women with uterine prolapse. 22 In parallel with the Ozdegirmenci et al study, 22 we showed that the mean smooth muscle percentage in the round ligament of the women with prolapse was significantly lower than in women with normal support. In addition to their study, we evaluated the muscle content by immunohistochemically by SMA and we also investigated the smooth muscle percentage of the uterosacral and cardinal ligaments of the uterus.…”

“…4,29,30 Zhu et al study 5 demonstrated no correlation between nerve fiber profiles and parity in SUI, POP, and control subjects. Contrary to this finding, Ozdegirmenci et al 22 have found a negative correlation between parity and smooth muscle content of the ligament in the study group. Our study showed that neuromuscular changes of the tissues are directly related to the parity, age and number of vaginal deliveries.…”

“…Most investigators studied only the connective tissue part 20 and the smooth muscle content 21,22 of the uterine ligaments. Some studies discovered the presence of nervous and vascular elements within the connective tissue of the uterosacral ligament 26,27 and cardinal ligament.…”

The role of smooth muscle in the pathogenesis of pelvic organ prolapse—an immunohistochemical and morphometric analysis of the cervical third of the uterosacral ligament

“…By morphometry of SMA immunostained areas in sections from the anterior vaginal apex, a significant reduction in smooth muscle cell content in women with POP compared to a control group was described [30]. In the round ligament, a significantly decreased smooth muscle fraction was morphometrically measured in H&E and Masson's trichrome slides from women with uterine prolapse [31]. In contrast, Gabriel et al [13] observed no difference in the fraction of smooth muscle in USL in postmenopausal women with or without POP.…”

Increased expression of matrix metalloproteinase 2 in uterosacral ligaments is associated with pelvic organ prolapse

“…There is some evidence that abnormalities of the connective tissue composition may contribute to the genesis of POP [8][9][10].…”