(607) Latency Changes in Penile Somatosensory Evoked Potentials Predict Real-World Efficacy of Topical Anesthesia

Introduction Prior research indicates that penile hypersensitivity in primary premature ejaculation (PPE) can be classified via somatosensory evoked potential (SEP) latency. This study investigates whether topical anesthetics treat PPE by prolonging this latency to delay ejaculation. Objective To assess the effect of topical anesthetics on penile SEP latency and their real-world treatment efficacy for premature ejaculation, and to determine if SEP latency changes can predict clinical outcomes. Methods 56 patients with PPE and penile hypersensitivity (5 with glans hypersensitivity only, 14 with shaft hypersensitivity only, 37 with full penile hypersensitivity) were enrolled. Penile SEP was performed before and 10 minutes after anesthetic application to evaluate changes in threshold, latency, and amplitude (the evaluation group). Patients then used the anesthetic only on the identified hypersensitive areas before sexual activity for two months (≥6 sexual encounters). Real-world efficacy was assessed via telephone follow-up, recording PEDT scores, IIEF-5 scores, and estimated IELT (eIELT). Results SEP assessment efficacy was defined as post-anesthetic latency extending to the normal range. Real-world efficacy was defined as a PEDT score <11 and eIELT >3 minutes. SEP assessment and real-world outcomes were consistent in 44/56 patients (78.57% consistency), with 90% sensitivity and 81.82% positive predictive value. Logistic regression revealed that the increase in latency at the glans (OR=2.78 per 1 ms) and shaft (OR=2.211 per 1 ms) post-application were positively correlated with real-world efficacy. Topical anesthetic application decreased IIEF-5 scores (P<0.05), and the incidence of erectile dysfunction (ED) was significantly higher in the shaft hypersensitivity group where the entire penis was covered (P<0.05). Conclusions Prolongation of penile SEP latency is associated with the efficacy of topical anesthetics for PPE, and the degree of latency change can predict real-world treatment success. However, anesthetic use can impair erectile function, a risk that may be mitigated by precise application only to hypersensitive areas. Disclosure No