Diagnostic accuracy of single channel cystometry for neurogenic bladder diagnosis following spinal cord injury: a pilot study.

INTRODUCTION: This is a cross-sectional study of 1 year duration (August 2013 to August 2014). The objective of the study was to investigate the diagnostic accuracy of single channel cystometry (SCC) for confirmation of neurogenic bladder following spinal cord injury.

MATERIALS AND METHODS: The study was conducted in both out-patient and in-patient services of Department of Rehabilitation Medicine, Hospital Sungai Buloh, Malaysia. Subjects in the study include sixteen patients with a clinical diagnosis of neurogenic bladder following spinal cord injury aged between 15 and 62 years. Patients with a clinical diagnosis of neurogenic bladder were subjected to cystometric evaluation using SCC in our hospital. Confirmation of the diagnosis was made by urodynamic study (UDS) in another hospital. SCC procedure involved manual intra-vesical pressure assessment using a 12F Nelaton catheter. Cystometric parameter measurement taken in this study was detrusor pressure (cm H2 O) done at regular intervals from baseline, throughout bladder filling phase and voiding/leaking phase. The relationship between detrusor pressure to bladder volume from initial bladder filling until voiding or leaking phase was recorded, analyzed and graph plotted. Maximum detrusor pressure (cm H2 O) during bladder filling, voiding or leaking and the maximum cystometric capacity (mls) was recorded.

RESULTS: SCC was found to have 100% sensitivity, 50% specificity, 93.33% positive predictive value and 100% negative predictive value for neurogenic bladder diagnosis. Only 55.55% patients with SCC suspicion of detrusor sphincter dyssynergia (DSD) had comparable UDS findings.

DISCUSSION: The use of SCC may be considered for objective confirmation of neurogenic bladder diagnosis following spinal cord lesion in centers with limited access to UDS. However, we are not able to establish its clinical application for confirmation of DSD.