Comparison of single and multichannel cystometry in diagnosing bladder instability.

The abilities of single channel cystometry and standard multichannel cystometry to diagnose bladder instability were compared in 100 women taking part in a single blind crossover trial. In 93 of the women both tests yielded the same result. The single channel system detected every case of detrusor instability but in seven women suggested detrusor contractions that were not evident on multichannel cystometry. These were probably due to changes in abdominal pressure. It is concluded that single channel cystometry when used in conjunction with simple urethral tests can provide most of the information that is obtained in specialist centres investigating bladder function.