Perucchini Daniele, DeLancey John O L, Ashton-Miller James A, Galecki Andrzej, Schaer Gabriel N
Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, USA.
Am J Obstet Gynecol. 2002 Mar;186(3):356-60. doi: 10.1067/mob.2002.121090.
The purpose of the study was to measure the thickness and cross-sectional area of urethral muscle layers to identify localized striated muscle loss.
The urethra and surrounding tissues from 25 female cadavers (mean age, 52 +/- 18 [SD] years; range, 15-80 years) were used for this study. Axial and median sagittal histologic sections were prepared. Median sagittal muscle layer thickness was measured every 10% of urethral length (each decile) in the dorsal wall (adjacent to the vagina) and ventral wall, beginning at the caudal margin of the detrusor muscle (0%) and ending at the caudal margin of the striated muscle (100%). In the midurethral cross-section, the thickness of each layer was measured along radial lines placed every 45 degrees with 0 degrees at the ventral midline and 180 degrees at the dorsal midline.
In the median sagittal sections, striated muscle layers of urethras were thinner at the vesical neck in older women. In the ventral wall, it decreased by a mean of 18 to 23 microm (3.4%-4.3%; P <.001) per year at 10% to 30% of urethral wall length. Dorsal striated muscle layers were thinner at every decile by 11 to 16 microm (3.2%-4.3%; P <.05); their total cross-sectional areas decreased by 0.19 mm2) (3.8%) per year short ( P <.001). In the midurethral cross-sections, the muscle was thinner by 16 to 25 microm (1.5% and 4.6%; P <.05) at 90, 135, and 180 degrees.
Striated muscle was lost at the bladder neck and along the dorsal wall of the urethra as women aged.
本研究旨在测量尿道肌层的厚度和横截面积，以确定局部横纹肌的损失情况。
本研究使用了25具女性尸体（平均年龄52±18[标准差]岁；范围15 - 80岁）的尿道及周围组织。制备了轴向和正中矢状面组织学切片。从逼尿肌尾缘（0%）开始，至横纹肌尾缘（100%）结束，在背壁（靠近阴道）和腹侧壁每隔尿道长度的10%（每个十分位数）测量正中矢状面肌层厚度。在尿道中段横切面，沿着每隔45度放置的径向线测量各层厚度，腹侧中线为0度，背侧中线为180度。
在正中矢状面切片中，老年女性尿道的横纹肌层在膀胱颈处较薄。在腹侧壁，在尿道壁长度的10%至30%处，每年平均减少18至23微米（3.4% - 4.3%；P <.001）。背侧横纹肌层在每个十分位数处均变薄11至16微米（3.2% - 4.3%；P <.05）；其总横截面积每年减少0.19平方毫米（3.8%）（P <.001）。在尿道中段横切面，在90度、135度和180度处肌肉变薄16至25微米（1.5%和4.6%；P <.05）。
随着女性年龄增长，膀胱颈和尿道背壁的横纹肌会出现损失。
