Penile Curvature Assessment in Hypospadias

Abstract

Penile curvature (PC) is often assessed during hypospadias surgery either alone or together with other phenotypic characteristics to determine which operation to perform. However, little is known about the accuracy and precision of the different methods used to estimate PC, despite widespread reporting of these figures in most hypospadias studies. The main challenge encountered when estimating PC in hypospadias cases is the lack of anatomic landmarks that define where curvature originates. In adults with Peyronie’s disease, curvature typically begins at the site of fibrous plaque thus creating hinge-type (HT) curvature that can be more easily quantified using a goniometer. However, in pediatric hypospadias, curvature is often distributed more evenly along the length of the penis, leading to arc-type (AT) curvature that is not amenable to manual estimations. Since PC in hypospadias is typically a combination of both arc and hinge types, accurate estimation of curvature likely requires complex computational approaches based on image recognition algorithms. While small degrees of error in PC measurement likely make little difference to patient outcome, it is still important to know the amount of error to be expected. Collaboration with computer engineers specialized in image recognition may move the field closer to a universally accepted method that can be used to perform more rigorous studies in future. (See Video 7.1).