URIKA, continuous ultrasound monitoring for the detection of a full bladder in children with dysfunctional voiding: A feasibility study

Objectives. To assess the feasibility of a new wearable, wireless ultrasonic device, the URIKA bladder monitor (UBM), in the detection of a full bladder in children with dysfunctional voiding (DV). Methods. This observational study included 14 children with DV who were subjected to an UBM monitoring session of 1.5-2 h. Transabdominal ultrasound (TUS) images were made as reference. The UBM measured the anterior-posterior bladder dimension by an ultrasound transducer, mounted in an elastic belt around the lower abdomen. Level of agreement between both methods was estimated by Bland-Altman analysis. Receiver operating characteristics (ROC) analysis was performed to determine a full bladder threshold for the studied population. Results. In 13 out of 14 patients, the UBM measured properly. Maximum bladder dimensions detected by the UBM and TUS were 6.69 ± 1.53 cm and 4.79 ± 0.99 cm respectively. Bland-Altman analysis showed a negative bias of -0.90 cm (limits of agreement: -4.1/+2.3 cm). ROC analysis resulted in a sensitivity and specificity of 78.3% and 100%, for a bladder dimension threshold of 5.03 cm. When this threshold was implemented a priori, the full bladder detection rate would have been 71%. In children younger than 10 years, this would be 100% (n = 5). Conclusion. The UBM is able to detect a full bladder with a detection rate of 71%, if a 5.03 cm threshold would be implemented. In patients younger than 10 years, the detection rate would be 100%. Future research will focus on increasing the UBM's accuracy and investigating the effect of UBM alarm treatment in children with urinary incontinence.