Comparison of results of nocturnal penile tumescence and rigidity in a sleep laboratory versus a portable home monitor.

OBJECTIVES To validate the results of the home penile tumescence monitor versus the sleep laboratory studies of erectile function. METHODS We used both methods to study 18 episodes of rigidity and 19 episodes of tumescence in 10 subjects with erectile dysfunction before and after the use of an experimental vasodilating medication. RESULTS The tumescence measurement in the sleep laboratory compared favorably with the changes in tumescence with the RigiScan portable home monitor: at the base (r = 0.70; P < 0.001), and at the tip (r = 0.84; P < 0.001). In measuring rigidity, the buckling pressure in the sleep laboratory compared favorably with the RigiScan measurements of percent average rigidity at the base (r = 0.56; P = 0.017), at the tip (r = 0.62; P = 0.006), and mean rigidity of the base and tip (r = 0.64; P = 0.004). In a comparison of the buckling pressure with the new RigiScan Plus quantitative program, there was good correlation with the rigidity activity units at the base (r = 0.70; P = 0.001) and at the tip (r = 0.72; P < 0.001). A clinical estimate of penetrable rigidity correlates with the RigiScan base rigidity of 55% to 60% and tip rigidity of about 50%. CONCLUSIONS The portable home monitor is a viable and cost-effective clinical tool to measure nocturnal penile activity.