Ice water test to predict long-term detrusor activity in persistent neurogenic acontractile detrusor

The aim of this study was to determine psychometric properties of Ice Water Test (IWT) to predict the appearance of a detrusor activity in patients with persistent neurogenic acontractile detrusor (NAD) following supra-sacral spinal cord lesion (SSL) and conus medullaris lesions or sacral spinal cord lesion (SSCL) and cauda equina with peripheral nerves lesion (CEPNL).

In this observational cohort study, we retrospectively reviewed medical files of consecutive patients followed in a tertiary neuro-urology unit between January 2008 and May 2018. Patients≥18 years, with NAD at first standard cystometry immediately followed by an IWT were included. Among the sixty-one patients screened, forty-eight patients were included for final analysis. Twenty-four had SSL/conus medullaris lesion, and twenty-four had SSCL/CEPNL. IWT was considered positive if it induced a non-inhibited detrusor contraction≥15cmH₂O. All patients were reviewed at least one year post IWT and detrusor activity was assessed by cystometry in long term.

Forty-eight patients were included, with a persistent NAD 1.5 [1-4.25] years after the injury. IWT as a test to predict at two years detrusor activity had a Se of 0.93 IC_95%[0.66-1] and a Sp of 0.91 IC_95%[0.76-0.98]. PPV and NPV were 0.81 IC_95%[0.59-0.93] and 0.97 IC_95%[0.82-1].

IWT could be a suitable test with robust psychometric properties to predict the development of detrusor activity at two years in SSL/conus medullaris and SSCL/CEPNL patients with persistent NAD.