女性低壓力膀胱開口阻塞之診斷線索

陳冠甫¹、范玉華^1,2、程威銘³、林登龍^1,2、林志杰^1,2、顧明軒^1,2、黃逸修^1,2

¹臺北榮民總醫院泌尿部；
²國立陽明交通大學醫學院泌尿學科及書田泌尿科學研究中心

³臺北市立聯合醫院忠孝院區泌尿外科

Diagnostic Clues for Low-Pressure Female Bladder Outlet Obstruction Missed by Conventional Urodynamics

Kuan-Fu Chen¹, Yu-Hua Fan^1,2, Wei-Ming Cheng ^2,3,Alex T. L. Lin ^1,2, Chih-Chieh Lin ^1,2,
Ming-Hsuan Ku ^1,2, Eric Yi-Hsiu Huang^1,2

¹ Department of Urology, Taipei Veterans General Hospital, Taipei, Taiwan;

² Department of Urology, College of Medicine and Shu-Tien Urological Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan

³ Division of Urology, Department of Surgery, Taipei City Hospital, Zhongxiao Branch, Taipei, Taiwan

Purpose:

Women with high-pressure, low-flow urodynamic patterns are typically diagnosed with bladder outlet obstruction (BOO). In contrast, low-pressure, low-flow BOO is frequently overlooked by conventional urodynamic studies (UDS). Videourodynamics (VUDS) provides additional diagnostic value in identifying BOO in such patients. Nevertheless, because of its limited availability and radiation exposure, VUDS is not routinely performed in women with voiding dysfunction, potentially resulting in misdiagnosis and undertreatment. This study aims to identify key parameters indicative of low-pressure, low-flow BOO in women classified as non-BOO by conventional UDS.

Materials and Methods:

Women with lower urinary tract symptoms who underwent VUDS at our center between July 2012 and October 2020 were retrospectively reviewed. BOO was defined as free maximal flow rate (Qmax) < 12 mL/s with a detrusor pressure at Qmax (PdetQmax) > 20 cmH₂O on conventional UDS, or as radiographic evidence of obstruction between the bladder neck and distal urethra in the presence of a sustained detrusor contraction on VUDS. Relevant comorbidities, surgical history, International Prostate Symptom Score (IPSS), and UDS parameters were collected and analyzed.

Results:

A total of 540 VUDS were reviewed, including 121 cases with BOO and 419 without BOO, based on the high-pressure, low-flow criteria. Among the 419 cases classified as non-BOO by these criteria, 128 (30.5%) demonstrated fluoroscopic evidence of BOO with low detrusor pressure on VUDS. The clinical characteristics of patients without high-pressure, low-flow BOO are presented in Table 1. The proportion of patients with a history of anti-incontinence surgery or pelvic organ prolapse repair, and those with an IPSS voiding-to-storage subscore ratio (V/S) greater than 1, was significantly higher among individuals with low-pressure BOO than among those without BOO. Patients with low-pressure BOO also exhibited significantly lower maximal and mean flow rates compared with patients without BOO. Age, diabetes mellitus, and history of pelvic surgery did not differ between the two groups. Multivariable logistic regression analysis (Table 2) revealed that a history anti-incontinence surgery or pelvic organ prolapse repair (p = 0.034; odds ratio: 2.071; 95% confidence interval: 1.057-4.058), as well as V/S > 1 (p = 0.023; odds ratio: 1.721; 95% confidence interval: 1.076-2.755), were significant predictors of low-pressure BOO. Additionally, age ≥ 70 years (p = 0.032; odds ratio: 0.542; 95% confidence interval: 0.310-0.948), and mean flow rate ≥ 10 mL/s (p = 0.0001; odds ratio: 0.208; 95% confidence interval: 0.112-0.384), were independent negative predictors of low-pressure BOO.

Conclusion: