CORRELATION OF PRESUMED CIRCLE AREA RATIO WITH INFRAVESICAL OBSTRUCTION IN MEN WITH LOWER URINARY-TRACT SYMPTOMS

Objectives, To examine the predictive value of ultrasonic measurements obtained by transrectal ultrasonography for infravesical obstruction as evaluated by pressure flow studies, Methods. In 85 men with moderat e to severe lower urinary tract symptoms, ultrasonic measurements incl uding prostatic volume, transition zone volume, transition zone index (transition zone volume/prostatic volume), and presumed circle area ra tio (PCAR) were compared with urodynamic parameters obtained by pressu re flow studies. Results. There were significant interrelationships be tween these ultrasonic measurements, which were all significantly grea ter in the obstructed patients than in the unobstructed patients, A si mple regression analysis demonstrated that prostatic volume (r = 0.362 , P < 0.001), transition zone volume (r = 0.373, P < 0.0005), transiti on zone index (r = 0.331, P < 0.005), and PCAR (r = 0.487, P < 0.0001) correlated significantly with the Abrams-Griffiths number. More impor tantly, a multiple regression analysis demonstrated PCAR to be the onl y independent determinant of the Abrams-Griffiths number. A receiver o perator characteristics curve analysis showed that 0.8 was the most su itable cutoff value of PCAR for the prediction of infravesical obstruc tion with a diagnostic accuracy of 76.5%. Conclusions, PCAR is useful as a transrectal ultrasonic measurement in assessing the severity of i nfravesical obstruction in men with lower urinary tract symptoms. (C) 1997, Elsevier Science Inc. All rights reserved.