[Clinical evaluation of isometric detrusor pressure in patients with benign prostatic hyperplasia]

The subjects chosen for this investigation were 88 patients with benign prostatic hyperplasia who proved not to have neurogenic bladder and 6 male volunteers without lower urinary tract disorders. In addition to the conventional preoperative urodynamic studies, isometric detrusor pressure was measured by the technique with balloon occlusion at the bladder neck. Although all 88 patients had undergone either transurethral resection of the prostate or subcapsular prostatectomy and routine postoperative examinations revealed sufficient canal formation in the prostatic urethra, in 23 patients (26.1%) a significant amount of residual urine was still observed and/or maximum urinary flow rate was considerably low. A retrospective analysis of the data from this study suggested that maximum isometric detrusor pressure is a useful parameter for the prediction whether or not micturition is improved after the removal of organic lower urinary tract obstruction, especially in cases with low detrusor pressure during urination. Furthermore, measurement of the maximum isometric detrusor pressure might be helpful in making the diagnosis of the clinical stage of benign prostatic hyperplasia, since several different stages could be defined by the value of maximum detrusor pressure during urination and maximum isometric detrusor pressure.