Christopher P Chung, Wilma I Larsen, Thomas J Kuehl
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引用次数: 0
Abstract
Introduction and hypothesis: Both humans and squirrel monkeys are susceptible to pelvic floor injury and prolapse from pregnancy, delivery, and aging. The mechanisms for external anal sphincter (EAS) injury in squirrel monkeys have not been evaluated in detail. This study evaluates a method for measuring EAS volume using magnetic resonance imaging (MRI) in squirrel monkeys and demonstrates the feasibility of serial measurements.
Methods: Using a previously described procedure, MRI was performed on 10 squirrel monkeys prior to euthanasia. After euthanasia, tissue blocks of EAS were cryo-sectioned and stained with succinic dehydrogenase to identify EAS striated muscle fibers. EAS volumes from both MRI and histological measurements were calculated using image analysis software. MRI measurements were obtained by two independent investigators. A cohort of four monkeys, each having five pregnancies and 11 MRI studies over a 5-year span, was used to evaluate EAS volume changes serially within females.
Results: Volumes measured by MRI for each squirrel monkey were similar for the two researchers (Cronbach alpha of 0.97 with 95% lower confidence limit of 0.92), and they were statistically consistent with the volumes obtained from analysis of histology (linear regression with R-squared of 0.97 and p < 0.0001). This validated technique was used to measure EAS volumes in four breeding females and demonstrated sufficient power to detect a decrease (p < 0.00001) from 32.1 ± 3.2 mm3 (mean ± SE) prior to the first pregnancy to 10.7 ± 1.5 mm3 after five pregnancies in 5 years.
Conclusion: Magnetic resonance imaging is a valid technique for measuring EAS volume changes in squirrel monkeys with sufficient sensitivity to detect EAS volume changes such that effects of aging and serial pregnancies can be evaluated.
期刊介绍：
The International Urogynecology Journal is the official journal of the International Urogynecological Association (IUGA).The International Urogynecology Journal has evolved in response to a perceived need amongst the clinicians, scientists, and researchers active in the field of urogynecology and pelvic floor disorders. Gynecologists, urologists, physiotherapists, nurses and basic scientists require regular means of communication within this field of pelvic floor dysfunction to express new ideas and research, and to review clinical practice in the diagnosis and treatment of women with disorders of the pelvic floor. This Journal has adopted the peer review process for all original contributions and will maintain high standards with regard to the research published therein. The clinical approach to urogynecology and pelvic floor disorders will be emphasized with each issue containing clinically relevant material that will be immediately applicable for clinical medicine. This publication covers all aspects of the field in an interdisciplinary fashion
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