A wearable adaptive penile rigidity monitoring system for assessment of erectile dysfunction

Abstract Erectile dysfunction (ED) is a prevalent type of sexual dysfunction, and continuous monitoring of penile tumescence and rigidity during spontaneous nocturnal erections is crucial for its diagnosis and classification. However, the current clinical standard device, limited by its active mechanical load, is bulky and nonwearable and strongly interferes with erections, which compromises both monitoring reliability and patient compliance. Here, we report a wearable adaptive rigidity monitoring (WARM) system that employs a measurement principle without active loads, allowing for the assessment of penile tumescence and rigidity through a specifically designed elastic dual-ring sensor. The dual-ring sensor, comprising two strain-sensing rings with distinct elastic moduli, provides high resolution (0.1%), robust mechanical and electrical stability (sustaining over 1000 cycles), and strong interference resistance. An integrated flexible printed circuit (FPC) collects and processes sensing signals, which are then transmitted to the host computer via Bluetooth for ED assessment. Additionally, we validated the WARM system against the clinical standard device using both a penile model and healthy volunteers, achieving high consistency. Furthermore, the system facilitates the continuous evaluation of penile erections during nocturnal tumescence tests with concurrent sleep monitoring, demonstrating its ability to minimize interference with nocturnal erections. In conclusion, the WARM system offers a fully integrated, wearable solution for continuous, precise, and patient-friendly measurement of penile tumescence and rigidity, potentially providing more reliable and accessible outcomes than existing technologies. Erectile dysfunction (ED) is a prevalent sexual dysfunction, and continuous monitoring of penile tumescence and rigidity during spontaneous nocturnal erections is crucial for its diagnosis and classification. However, the current clinical standard device, limited by its active mechanical load, is bulky, nonwearable, and creates pronounced interference with erections, which compromises both monitoring reliability and patient compliance. Here, we report a wearable adaptive rigidity monitoring (WARM) system (Fig. 1a) that employs a measurement principle without active loads (Fig. 1b), allowing for the assessment of penile tumescence and rigidity through a specifically designed elastic dual-ring sensor. The dual-ring sensor, comprising two strain-sensing rings with distinct elastic moduli, provides high resolution (0.1%), robust mechanical and electrical stability (sustaining over 1000 cycles), and strong interference resistance. Additionally, we validate the WARM system against the clinical standard device using both a penile model and healthy volunteers, achieving high consistency. Furthermore, the system facilitates the continuous evaluation of penile erections during nocturnal tumescence tests, with concurrent sleep monitoring, demonstrating its ability to minimize interference with nocturnal erections (Fig. 1c). In conclusion, the WARM system offers a fully integrated, wearable solution for continuous, precise, and patient-friendly measurement of penile tumescence and rigidity, potentially providing more reliable and accessible outcomes than those from existing technologies.