Advantages and limitations of sleep-related erection and rigidity monitoring: a review

Abstract

Over the past decades, sleep-related erection and rigidity monitoring has been used to differentiate psychogenic from organic erectile dysfunction (ED), due to the involuntary nature of erections in sleep. This study retrospectively reviewed all available literature focusing on sleep-related erection and rigidity monitoring through a systematic PubMed search. To date, there are mainly seven methods and their modifications, including: sleep laboratory testing, the mercury strain gauge, the stamp test, the erectometer, the Snap gauge, the RigiScan, and nocturnal electrobioimpedance volumetric assessment. This study analyzes and summarizes the advantages and limitations of seven monitoring methods. This study indicates that both of the above methods possess the capacity to assess erectile quality and provide guidance to the diagnosis, etiology, and differential diagnosis of ED. However, some limitations still exist for the application. New devices which can continuously monitor kinds of variables, including sleep-related erection, axial and radial rigidity, and oxygen saturation are needed.

European Association of Urology Guidelines on Sexual and Reproductive Health—2021 Update: Male Sexual Dysfunction

“…For the nocturnal penile tumescence and rigidity (NPTR) test, nocturnal monitoring devices are used to measure the number of erectile episodes, tumescence (circumference change by strain gauges), maximal penile rigidity, and duration of nocturnal erection(s) [121][122][123]. NPTR monitoring is considered an additional test for even more objectively differentiating between organic and psychogenic ED (patients with psychogenic ED usually have normal findings in the NPTR test), but many potential confounding factors (eg, situational) may limit its routine use solely for diagnostic purposes [121,124].…”

Current approaches to the diagnosis of vascular erectile dysfunction

“…In addition, wearable devices have been proved to be able to detect cardiac rhythms to identify arrhythmias early (91)(92)(93). Similar to the principle of these wearable devices, new methods of long-term dynamic detection of erectile function are needed (94). During penile erection, increased arterial blood inflow leads to an increase in oxygen saturation, so monitoring oxygen saturation can reflect the function of penile blood vessels.…”

Absence of Nocturnal Penile Tumescence: An Earlier Sign of Erectile Dysfunction and Its Linked Comorbid Conditions

“…The most cost-effective method is the stamp test, but the most extensively used and trusted tool is RigiScan. 67 conclusIon Nocturnal penile tumescence are the natural erections present in all healthy men during sleep. Absence of NPT can be a good indicator for future dysfunction of reproductive system especially the ED.…”