{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:55:37Z","timestamp":1787028937174,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T00:00:00Z","timestamp":1760313600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: To evaluate the effect of a ureteral access sheath (UAS) on the maximal intra-pelvic pressure (IPP max) during retrograde lithotripsy of hard and soft stones in a porcine model. Materials and Methods: A 22 Fr percutaneous tract was established in the upper calyces of the kidneys in three female pigs. A custom-made Foley catheter with a urodynamic catheter was inserted into the pelvicalyceal system and connected to a urodynamic device for real-time IPP measurement. A Pusen Uscope 7.5 Fr single-use ureteroscope (Zhuhai Pusen Medical Technology, Jinhua, China) with manual pump irrigation was used. BegoStone\u2122 powder (Bego, Lincoln, RI, USA) was prepared in two powder-to-water ratios (15:3 and 15:6) to create hard and soft stones, respectively. Stones were positioned in the pelvicalyceal system through the percutaneous tract, and retrograde intrarenal lithotripsy was performed in three settings: without UAS and with a 9.5\/11 Fr UAS, with lasing in the center of the pelvis, and during lithotripsy of soft and hard stones. Results: With manual pump irrigation and without a UAS, the IPP max reached 55 cmH2O during lasing in the pelvis center. During lithotripsy of soft and hard stones, the IPP max increased to 62 and 65 cmH2O, respectively. Using a UAS, the IPP max was significantly lower: 18 cmH2O in the center of the pelvis, and 25 and 29 cmH2O during lithotripsy of soft and hard stones, respectively. Conclusions: Manual pump irrigation without a UAS can elevate IPP max to potentially unsafe levels during retrograde correct flexible lithotripsy, even when using a 7.5 Fr flexible scope. The addition of a UAS helps maintain the IPP max within safer limits.<\/jats:p>","DOI":"10.3390\/medicina61101829","type":"journal-article","created":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T13:13:27Z","timestamp":1760361207000},"page":"1829","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Is a Ureteral Access Sheath Necessary for Maintaining Safe Intrarenal Pressures During Retrograde Lithotripsy Using a Flexible 7.5 Fr Scope and a High-Power TFL? In Vivo Experimental Study"],"prefix":"10.3390","volume":"61","author":[{"given":"Athanasios","family":"Vagionis","sequence":"first","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8584-3888","authenticated-orcid":false,"given":"Vasileios","family":"Tatanis","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0427-4506","authenticated-orcid":false,"given":"Angelis","family":"Peteinaris","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-1640-1058","authenticated-orcid":false,"given":"Paraskevi","family":"Katsakiori","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasiliki","family":"Tsekoura","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1657-9689","authenticated-orcid":false,"given":"Konstantinos","family":"Pagonis","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9961-4883","authenticated-orcid":false,"given":"Theofanis","family":"Vrettos","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and ICU, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5544-9636","authenticated-orcid":false,"given":"Evangelos","family":"Liatsikos","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"},{"name":"Department of Urology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panagiotis","family":"Kallidonis","sequence":"additional","affiliation":[{"name":"Department of Urology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1016\/j.eururo.2015.07.041","article-title":"EAU Guidelines on Interventional Treatment for Urolithiasis","volume":"69","author":"Sarica","year":"2016","journal-title":"Eur. 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