Most cited article - PubMed ID 15672007
INTRODUCTION AND HYPOTHESIS: We aimed to summarize the knowledge on the pathogenesis of pelvic organ prolapse (POP) generated in animal models. METHODS: We searched MEDLINE, Embase, Cochrane and the Web of Science to establish what animal models are used in the study of suggested risk factors for the development of POP, including pregnancy, labor, delivery, parity, aging and menopause. Lack of methodologic uniformity precluded meta-analysis; hence, results are presented as a narrative review. RESULTS: A total of 7426 studies were identified, of which 51 were included in the analysis. Pregnancy has a measurable and consistent effect across species. In rats, simulated vaginal delivery induces structural changes in the pelvic floor, without complete recovery of the vaginal muscular layer and its microvasculature, though it does not induce POP. In sheep, first vaginal delivery has a measurable effect on vaginal compliance; measured effects of additional deliveries are inconsistent. Squirrel monkeys can develop POP. Denervation of their levator ani muscle facilitates this process in animals that delivered vaginally. The models used do not develop spontaneous menopause, so it is induced by ovariectomy. Effects of menopause depend on the age at ovariectomy and the interval to measurement. In several species menopause is associated with an increase in collagen content in the longer term. In rodents there were no measurable effects of age apart of elastin changes. We found no usable data for other species. CONCLUSION: In several species there are measurable effects of pregnancy, delivery and iatrogenic menopause. Squirrel monkeys can develop spontaneous prolapse.
- Keywords
- Age, Menopause, Ovariectomy, Parity, Pathophysiology, Pregnancy,
- MeSH
- Rats MeSH
- Models, Animal MeSH
- Sheep MeSH
- Pelvic Floor MeSH
- Parity MeSH
- Pelvic Organ Prolapse * MeSH
- Pregnancy MeSH
- Delivery, Obstetric MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Pregnancy MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Systematic Review MeSH
INTRODUCTION AND HYPOTHESIS: Er:YAG laser is frequently used in dermatology and gynecology. Clinical studies document high satisfaction rates; however, hard data on the effects at the structural and molecular levels are limited. The aim of this systematic review was to summarize current knowledge about the objective effects of non-ablative Er:YAG laser on the skin and vaginal wall. METHODS: We searched MEDLINE, Embase, Cochrane, and the Web of Science. Studies investigating objectively measured effects of non-ablative Er:YAG laser on the skin or vaginal wall were included. Studies of any design were included. Owing to the lack of methodological uniformity, no meta-analysis could be performed and therefore results are presented as a narrative review. RESULTS: We identified in vitro or ex vivo studies on human cells or tissues, studies in rats, and clinical studies. Most studies were on the skin (n = 11); the rest were on the vagina (n = 4). The quality of studies is limited and the settings of the laser were very diverse. Although the methods used were not comparable, there were demonstrable effects in all studies. Immediately after application the increase in superficial temperature, partial preservation of epithelium and subepithelial extracellular matrix coagulation were documented. Later, an increase in epithelial thickness, inflammatory response, fibroblast proliferation, an increase in the amount of collagen, and vascularization were described. CONCLUSIONS: Er:YAG laser energy may induce changes in the deeper skin or vaginal wall, without causing unwanted epithelial ablation. Laser energy initiates a process of cell activation, production of extracellular matrix, and tissue remodeling.
