The Value of Ambulatory Urodynamics in the Evaluation of Treatment Effect of Sacral Neuromodulation

Abstract

Objectives: To assess the improvement of symptoms by sacral neuromodulation (SNM) in an objective way by carrying out an ambulatory urodynamic study (ambulatory-UDS). Until now, successful treatment has been defined as a ≥50% improvement recorded on voiding diaries. Voiding diaries are a patient reported outcome tool. A tool with less bias is desired to evaluate the treatment results before an expensive permanent system is implanted. Methods: Between 2002 and 2015, a total of 334 patients with lower urinary tract symptoms were included consecutively in an ambulatory-UDS database. From this database, a subgroup of patients was selected which underwent SNM. Results: In 51 patients, an ambulatory-UDS was performed both at baseline and during the SNM test period. A positive treatment outcome after test stimulation based on the patients' voiding diary, correlated ( p < 0.0001) with an improvement on ambulatory-UDS. Twenty-six of the 30 patients, who have showed improvement of more than 50% on voiding diary parameters and who had subjective improvement of their symptoms, showed an early improvement on ambulatory-UDS. Conclusions: Ambulatory-UDS can be used in clinical decision making, as it is associated with voiding diary improvement during the SNM test period. Using ambulatory-UDS to confirm success could in the future justify the shortening of the test period.