Comparison of microtransducer and fiberoptic catheters for urodynamic studies

OBJECTIVE: To assess the validity and reproducibility of a fiberoptic transducer urodynamic catheter for urethral closure pressure profiles and leak point pressure determination, using a microtransducer catheter as the standard. METHODS: Ninety women without significant pelvic organ prolapse underwent urodynamic evaluations with both fiberoptic and microtransducer catheters. Maximal urethral closure pressures and "leak point pressures" were repeatedly measured by the two catheters and statistically compared. The order of catheter use was randomized. RESULTS: Significantly lower mean maximal urethral closure pressures were recorded by the fiberoptic system than by the microtransducer system (28.9 cmH(2)O +/- 17.3 versus 43.2 cmH(2)O +/- 24.9, P <.001). The fiberoptic catheter predicted microtransducer values for maximum urethral closure pressure only within a range of 27 cmH(2)O. Mean "leak point pressure" recorded by the fiberoptic catheters (66.9 cmH(2)O +/- 2.9) was not significantly different than that recorded by the microtransducer catheters (66.4 cmH(2)O +/- 2.9, P =.97). CONCLUSION: There is a significant difference between maximum urethral closure pressure values recorded by the microtransducer and fiberoptic catheter systems. No significant difference was found between the two systems in measurement of Valsalva "leak point pressure."