基于盆底MRI评估年龄与前列腺癌根治术对男性盆底解剖结构及尿控的影响

Effect of age and radical prostatectomy on related changes in male pelvic floor anatomy and urinary continence based on pelvic MRI

目的:使用动静态盆底磁共振成像(MRI)评估健康志愿者与有排尿症状的老年男性患者的尿道长度、盆底肌肉厚度以及盆腔脏器在静息期与力排期的运动情况,探讨盆底MRI检查显示老年性及前列腺癌根治术(RP)相关的盆底解剖与功能变化以及分析有关下尿路症状的重要性。方法:于郑州大学第一附属医院收集无盆底功能障碍(PFD)成年男性(对照组)、进行性排尿困难的良性前列腺增生(BPH)患者与腹腔镜前列腺癌根治术(LRP)后出现压力性尿失禁(SUI)的患者行动静态盆底MRI检查。在盆底MRI上测量前列腺体积(PV)、膜性尿道长度(MUL)、耻骨直肠肌(PRM)厚度、静息期及力排期H线、M线、肛管直肠角(ANA)的大小以及其变化范围。使用单因素方差分析(正态分布且方差齐)或Kruskal Wallis检验(偏态分布或方差不齐)比较三组间计量资料的差异,使用Spearman相关性分析评估两组未手术组中MRI参数与年龄是否具有相关性。结果:纳入对照组28例,BPH组39例,SUI组32例。①对照组盆底MRI参数95%置信区间上下限如下:PV(16.11,21.01)cm^(3),MUL(16.66,18.28)mm,PRM(4.27,5.04)mm,静息期H线(44.20,48.32)mm,力排期H线(46.59,50.62)mm,静息期M线(12.11,15.03)mm,力排期M线(16.28,21.03)mm,静息期ANA(98.87,107.30)°,力排期ANA(103.15,112.55)°;②三组间PV、MUL、PRM厚度、静息期及力排期H线、M线变化范围、静息期及力排期ANA的差异均有统计学意义(P<0.05),两两比较结果显示:PV:BPH组>SUI组>对照组,MUL:BPH组与对照组>SUI组,PRM厚度:对照组>SUI组,静息期及力排期H线:BPH组>对照组,静息期及力排期ANA:BPH组与对照组<SUI组(P<0.05),任意两组间M线的变化范围的差异无统计学意义(P>0.05);③PV(r=0.660)、静息期及力排期H线(r=0.323、r=0.303)与年龄呈正相关(P<0.05),PRM(r=-0.292)与年龄呈负相关(P<0.05)。结论:动静态盆底MRI检查显示老龄会引起PV增大,盆底肌的萎缩及盆膈裂孔的扩大,LRP则显著造成MUL的缩短及ANA的增加。MRI检查通过高分辨率和优越的软组织对比度可以对盆腔解剖细节和功能数据进行量化,有利于临床医师了解老年及LRP术后男性与正常成年男性盆底结构的解剖和功能差异,并为预测老年性及术后相关的排尿症状提供客观依据。

Objective:To investigate the changes of pelvic floor anatomy and function associated with elderly and radical prostatectomy(RP)and the importance of monitoring relevant lower urinary tract symptoms by evalu-ating length of urethra,pelvic floor muscle thickness and the movement of pelvic organs during resting phase and Valsalva maneuver in healthy volunteers and patients with voiding symptoms using static and dynamic pelvic MRI.Methods:Adult male without pelvic floor dysfunction(control group),benign prostatic hyperplasia(BPH)pa-tients with progressive dysuria and patients with stress urinary incontinence(SUI)after laparoscopic radical pros-tatectomy(LRP)in First Affiliated Hospital of Zhengzhou University were collected.All subjects underwent dy-namic and static pelvic floor MRI.Prostate volume(PV),membranous urethral length(MUL),the thickness of puborectal muscle(PRM),H-line,M-line and anorectal angle(ANA)were measured on pelvic floor MRI and the variation of pelvic floor function parameters were calculated.One-Way ANOVA or Kruskal Wallis test was used to compare these parameters among the three groups.Spearman correlation analysis was used to evaluate whether these parameters were correlated with age in two unoperated groups.Results:These parameters were compared a-mong control group(n=28),BPH group(n=39),SUI group(n=32).①MRI parameters of healthy control group were as follows:PV(16.11,21.01)cm^(3),MUL(16.66,18.28)mm,PRM(4.27,5.04)mm,H line in resting phase(44.20,48.32)mm,H line in straining phase(46.59,50.62)mm,M line in resting phase(12.11,15.03)mm,M line in straining phase(16.28,21.03)mm,ANA in resting phase(98.87,107.30)°,ANA in straining phase(103.15,112.55)°.②The PV,MUL,the thickness of PRM,H line of two phases,the change of M line,ANA of two phases were statistically significant among three groups(P<0.05).Made pairwise comparisons based on the above results:PV:BPH group>SUI group>control group,MUL:control group and BPH group>SUI group,the thickness of PRM:control group>SUI group,H line of two phases:BPH group>control group,the change of M line:no significant difference(P>0.05),ANA of two phases:SUI group>con-trol group and BPH group(P<0.05).③PV(r=0.660),H line of two phases(r=0.323,r=0.303)were positively correlated with age(P<0.05),while PRM(r=-0.292)was negatively correlated with age(P<0.05).Conclusion:Dynamic and static pelvic floor MRI showed that aging could cause increasement of PV,atro-phy of pelvic floor muscle and enlargement of pelvic diaphragmatic hiatus,while LRP could cause shortening of MUL and increasement of ANA.MRI can quantify pelvic anatomical details and functional data by high resolution and superior soft tissue contrast,to offer the anatomical and morphological differences of pelvic structures in elder men,patients after LRP and healthy adult men to clinicians and provide objective basis for predicting senile and postoperative urination symptoms.