{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T11:34:52Z","timestamp":1778240092748,"version":"3.51.4"},"reference-count":16,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2025,3,10]],"date-time":"2025-03-10T00:00:00Z","timestamp":1741564800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Neurourology and Urodynamics"],"published-print":{"date-parts":[[2025,4]]},"abstract":"<jats:title>ABSTRACT<\/jats:title><jats:sec><jats:title>Objective<\/jats:title><jats:p>Sacral neuromodulation (SNM) is an established treatment for detrusor underactivity (DU) and nonobstructive urinary retention. The mechanism of action for SNM in DU, however, remains poorly understood. The objective of this study was to investigate the urodynamic study (UDS) changes in DU patients during the trial period following first stage tined\u2010lead placement (FSTLP).<\/jats:p><\/jats:sec><jats:sec><jats:title>Materials and Methods<\/jats:title><jats:p>Retrospective chart review was performed to identify patients diagnosed with DU on initial UDS, who had repeat UDS during the 2\u2010week trial period following FSTLP by a single clinician. Urodynamic parameters including maximum flow rate (Qmax), detrusor pressure at maximum flow (PdetQmax), post\u2010void residual (PVR), voiding efficiency (VE), and detrusor contractility index (DCI) were collected. Using the definition of improvement in baseline VE of \u2265\u200950% post\u2010FSTLP or improvement in DCI of \u2265\u200950% in complete voiders, patients were divided into \u201cresponders\u201d and \u201cnonresponders.\u201d Pre\u2010 and post\u2010FSTLP urodynamic findings were compared using Wilcoxon signed\u2010rank tests.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>A total of 17 patients were identified who met the inclusion criteria. Repeat UDS were done on account of inability or unwillingness to perform clean intermittent catheterization and thus inability to chart an accurate bladder diary. There were 9 female and 8 male patients. Four patients (23.5%) had pure DU while the other 13 (76.5%) had concurrent detrusor overactivity (DO\u2013DU). Among all patients, there was a statistically significant improvement in PdetQmax (14 vs. 29\u2009cmH<jats:sub>2<\/jats:sub>O, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.01) and DCI (62 vs. 92, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.01). Six patients (35.3%) responded to the trial of SNM for DU. Among responders, statistically significant improvements in Qmax (5 vs. 15.5\u2009mL\/s, <jats:italic>p<\/jats:italic>\u2009=\u20090.03), PVR (215 vs. 80 mLs, <jats:italic>p<\/jats:italic>\u2009=\u20090.04), VE (22.9% vs. 82.5%, <jats:italic>p<\/jats:italic>\u2009=\u20090.04), and DCI (29 vs. 97.5, <jats:italic>p<\/jats:italic>\u2009=\u20090.03) were observed. Nonresponders had improvement in PdetQmax (14 vs. 29\u2009cmH<jats:sub>2<\/jats:sub>O, <jats:italic>p<\/jats:italic>\u2009=\u20090.02), but not in Qmax (9 vs. 10\u2009mL\/s, <jats:italic>p<\/jats:italic>\u2009=\u20090.89).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>Among all patients, an improvement in PdetQmax and DCI was observed. Responders exhibited improvement in Qmax, PVR, VE, and DCI without statistically significant improvement in PdetQmax. Nonresponders had statistically significant improvement in PdetQmax, but not in Qmax. Possible mechanisms of action of SNM in DU patients based on our data are inhibition of the guarding reflex\/relaxation of the urethra (shown by improvement in Qmax in responders only) and direct strengthening of bladder contractility (shown by improvement in PdetQmax in all patients). Improvement in Qmax was observed exclusively in responders suggesting the former mechanism is the predominant one. Further larger prospective studies are required to confirm these findings.<\/jats:p><\/jats:sec>","DOI":"10.1002\/nau.70035","type":"journal-article","created":{"date-parts":[[2025,3,12]],"date-time":"2025-03-12T05:12:20Z","timestamp":1741756340000},"page":"804-810","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Urodynamic Changes Following a Staged Trial of Sacral Neuromodulation in Patients With Detrusor Underactivity"],"prefix":"10.1002","volume":"44","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3721-956X","authenticated-orcid":false,"given":"Stewart","family":"Whalen","sequence":"first","affiliation":[{"name":"Department of Urology Austin Health Heidelberg Victoria Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-2570-0478","authenticated-orcid":false,"given":"Jaraspong","family":"Vuthiwong","sequence":"additional","affiliation":[{"name":"Department of Surgery, Faculty of Medicine Chiang Mai University Chiang Mai Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5710-1983","authenticated-orcid":false,"given":"Liang G.","family":"Qu","sequence":"additional","affiliation":[{"name":"Department of Urology Eastern Health Boxhill Victoria Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Johan","family":"Gani","sequence":"additional","affiliation":[{"name":"Department of Urology Austin Health Heidelberg Victoria Australia"},{"name":"Department of Urology Western Health Footscray Victoria Australia"},{"name":"The University of Melbourne Melbourne Victoria Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2025,3,10]]},"reference":[{"key":"e_1_2_12_2_1","doi-asserted-by":"publisher","DOI":"10.1002\/tre.934"},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/nau.20979"},{"key":"e_1_2_12_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/nau.24893"},{"key":"e_1_2_12_5_1","doi-asserted-by":"publisher","DOI":"10.1038\/ncpuro1251"},{"key":"e_1_2_12_6_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.ju.0000113201.26176.8f"},{"key":"e_1_2_12_7_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1464-410X.1997.00145.x"},{"key":"e_1_2_12_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-5347(05)67826-3"},{"key":"e_1_2_12_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-5347(05)00335-6"},{"key":"e_1_2_12_10_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1464-410X.2007.07258.x"},{"key":"e_1_2_12_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-5347(05)67728-2"},{"key":"e_1_2_12_12_1","doi-asserted-by":"publisher","DOI":"10.1002\/nau.24252"},{"key":"e_1_2_12_13_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ucl.2004.09.004"},{"key":"e_1_2_12_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/nau.23255"},{"key":"e_1_2_12_15_1","doi-asserted-by":"publisher","DOI":"10.1111\/luts.12325"},{"key":"e_1_2_12_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.juro.2017.12.053"},{"key":"e_1_2_12_17_1","doi-asserted-by":"publisher","DOI":"10.1111\/ner.12017"}],"container-title":["Neurourology and Urodynamics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/nau.70035","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,4,24]],"date-time":"2025-04-24T03:18:06Z","timestamp":1745464686000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/nau.70035"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3,10]]},"references-count":16,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2025,4]]}},"alternative-id":["10.1002\/nau.70035"],"URL":"https:\/\/doi.org\/10.1002\/nau.70035","archive":["Portico"],"relation":{},"ISSN":["0733-2467","1520-6777"],"issn-type":[{"value":"0733-2467","type":"print"},{"value":"1520-6777","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,3,10]]},"assertion":[{"value":"2024-11-27","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-02-19","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-03-10","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}