Bump R C, Coates K W, Cundiff G W, Harris R L, Weidner A C
Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, NC 27710, USA.
Am J Obstet Gynecol. 1997 Aug;177(2):303-10. doi: 10.1016/s0002-9378(97)70191-1.
Our purpose was to compare three measures proposed to diagnose intrinsic sphincteric deficiency: maximum urethral closure pressure, Valsalva leak point pressure, and straining urethral axis.
A total of 159 women with pure genuine stress incontinence had the three measures determined in a standardized fashion. Critical cutoff values for the Valsalva leak point pressure (52 cm) and urethral axis (22 degrees) were established by examining relative frequency distribution curves, using closure pressure of 20 as the arbitrary benchmark value for the prevalence of intrinsic sphincteric deficiency. The distribution of cutoff values is described and differences among the measures with respect to risk factors for intrinsic sphincteric deficiency and incontinence severity were determined.
Half the subjects fell below at least one cutoff value, but only 10% fell below all three. Sixty-four percent of subjects with either low closure pressure or leak point pressure had low values for the other, whereas 21% had discordance between them. Only 53% of subjects with low closure pressure and 40% with low leak point pressure had an axis < or = 22 degrees. Conversely, a substantial portion (36%) of subjects with pure genuine stress incontinence without urethral hypermobility had neither low urethral or leak point pressures. All three cutoff-values were associated with risk factors for intrinsic sphincteric deficiency, but only low closure and leak point pressures had significant associations with the severity of incontinence.
Intrinsic sphincteric deficiency should be diagnosed by a composite of historic, urodynamic, anatomic, and clinical severity criteria. We would include a maximum urethral closure pressure < or = 20, a Valsalva leak point pressure < or = 50, and a stress urethral axis < or = 20 in this composite.
我们的目的是比较三种用于诊断固有括约肌功能不全的指标：最大尿道闭合压、瓦尔萨尔瓦漏尿点压和用力时尿道轴。
总共159名单纯性真性压力性尿失禁女性以标准化方式测定了这三种指标。通过检查相对频率分布曲线，以20作为固有括约肌功能不全患病率的任意基准值，确定了瓦尔萨尔瓦漏尿点压（52厘米）和尿道轴（22度）的临界截断值。描述了截断值的分布，并确定了这些指标在固有括约肌功能不全的危险因素和尿失禁严重程度方面的差异。
一半的受试者至少低于一个截断值，但只有10%的受试者低于所有三个截断值。64%的最大尿道闭合压或漏尿点压低的受试者另一个指标值也低，而21%的受试者两者不一致。最大尿道闭合压低的受试者中只有53%、漏尿点压低的受试者中只有40%的尿道轴≤22度。相反，相当一部分（36%）无尿道活动过度的单纯性真性压力性尿失禁受试者既没有低尿道压也没有低漏尿点压。所有三个截断值都与固有括约肌功能不全的危险因素相关，但只有低闭合压和低漏尿点压与尿失禁严重程度有显著关联。
固有括约肌功能不全应通过病史、尿动力学、解剖学和临床严重程度标准的综合来诊断。我们建议该综合标准包括最大尿道闭合压≤20、瓦尔萨尔瓦漏尿点压≤50和应力性尿道轴≤20。
