Introduction: Uroflowmetry or uroflow is an important tool for the assessment and management of patients with lower urinary tract symptoms (LUTS). Traditionally, the system requires a patient to urinate into a weight-sensing or gravimetric collection vessel and then outputs urine flowrate or volume over time. Although non-invasive, this approach has major limitations. Patients undergo testing in uncomfortable and unrepresentative voiding environments that may compromise diagnostic accuracy. Furthermore, it requires manual cleaning and setup between each use, which leads to interruptions in clinic workflow and longer wait times. This study aims to design and implement a toilet-attached uroflow device that performs the same standard of care measurements as gravimetric uroflow, but inside any standard toilet and without an external urine collection vessel.

Methods: The design leverages micro-electromechanical flow sensors housed in a unit that attaches via universal adapters to any standard toilet. Voided urine passes into the device to be measured, then empties into the toilet automatically. Standard uroflow metrics are output by custom software. Multiple flow states were simulated using saline irrigation bags and the device performance was tested for accuracy against a standard gravimetric uroflow device.

Results: The novel uroflow device enables uroflow measurements in any standard toilet and automatically empties after each use. The device is accurate to within ±5% for total volume and ±1 cc/sec for maximum and average flow rates, consistent with International Continence Society equipment performance guidelines.

Conclusions: This novel uroflow device has the potential to reduce disruptions to clinician workflow, improve diagnostic accuracy through more representative voiding, and enhance the patient experience through improved comfort, reduced test anxiety, and shorter wait times. A trial is being conducted to confirm results in an outpatient urology clinic.