I will reach out to these clinicians since they are actually measuring penile sensitivity.
MP74-07
THE PENILE SENSITIVITY RATIO: OPTIMIZATION OF A BIOTHESIOMETRY PARAMETER TO ASSESS CHANGES IN PENILE SENSITIVITY
Peter Tsambarlis, Adam Wiggins, M. Ryan Farrell, and Laurence Levine
INTRODUCTION AND OBJECTIVES
Penile sensitivity ratio (PSR) was previously developed at our institution to standardize biothesiometry data and reduce variability. Significant associations with PSR were reported diminished sensation, age, and Peyronie's disease (PD). We sought to optimize the input variables comprising the PSR.
METHODS
We performed a retrospective analysis of all men who underwent biothesiometry at a single urology practice specializing in men's health from 7/2013-5/2017. PSR was initially defined as the mean biothesiometry threshold for sensation of the dorsal and ventral glans divided by the mean sensation threshold of the left and right index finger. Thus, a higher PSR indicates diminished penile sensation. We compared this ratio to models which included biothesiometry data from the penile shaft and anterior thigh. Univariate and multiple regression analyses were performed for each iteration of the ratio. Patient factors included: age, diabetes mellitus (DM), PD, erectile dysfunction (ED), ejaculatory dysfunction (premature vs. delayed vs. normal function), and subjective diminished sensation.
RESULTS
Our analysis included 1239 men with mean age of 53.2 years (SD=14.0 years). The original PSR was significantly higher in men who reported diminished sensitivity compared to men who reported normal penile sensation, 2.09 and 1.94 respectively (p =0.01). Adding mean left and right shaft to the numerator and mean left and right thigh data to the denominator of the previously described PSR lead to a model in which diminished sensitivity did not affect the ratio (p = 0.20). Alternatively, when glans and shaft data were included against the index fingers only, reported diminished sensitivity increased the ratio (p=0.03). On multiple regression analysis using the ratio of the mean glans and shaft values divided by the mean index finger values, the ratio was significantly affected by age, DM, and PD, but not reported diminished sensation.
CONCLUSIONS
The current analysis does not support the inclusion of data from the shaft or thigh, as reported diminished sensation did not affect these ratios, suggesting a lack of internal validity. The original PSR using data from the glans and index fingers appears to most accurately represent clinically significant changes in penile sensitivity. Further prospective data collection including other internal controls such as the cheek may further optimize the PSR.
