{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,16]],"date-time":"2026-08-16T04:26:35Z","timestamp":1786854395199,"version":"build-2736575974"},"reference-count":31,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002241","name":"Japan Science and Technology Agency","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/00097mb19","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>(1) Background: To compare tube resistance among glaucoma drainage devices (GDDs) with different tube geometries under various intraluminal polypropylene (PP) thread conditions and assess agreement between measured and formula-derived pressure\u2013flow profiles. (2) Methods: Four GDDs were evaluated: Ahmed ClearPath Small Tube (ACP-ST), Paul Glaucoma Implant (PGI), Ahmed ClearPath (ACP), and Virna Glaucoma Implant (VGI) (n = 4\/device). ACP-ST and PGI were tested under no-thread, 6-0 PP Corza, and 6-0 PP Ethicon conditions, whereas ACP and VGI were tested under no-thread, 4-0 PP Corza, and 3-0 PP Ethicon conditions. Saline was infused at 1.0\u20135.0 \u00b5L\/min, and pressure was recorded using a transducer system. Tube and thread dimensions were measured using ImageJ and used to calculate formula-derived pressure from fluid dynamic equations. Comparisons used linear mixed-effects regression. (3) Results: In ACP-ST and PGI, both 6-0 PP threads significantly increased pressure compared with the no-thread condition, with no significant thread manufacturer-related differences. In ACP and VGI, all threaded conditions significantly increased pressure, and the 3-0 PP Ethicon condition produced higher pressure than the 4-0 PP Corza condition. Under threaded conditions, measured and formula-derived pressure values did not differ significantly in ACP-ST but differed significantly in PGI, ACP, and VGI. (4) Conclusions: Intraluminal PP threads increased GDD tube resistance. Manufacturer-related differences had a limited influence on resistance in small-lumen devices. Agreement between measured and formula-derived pressure varied among devices, highlighting the importance of experimental validation. These findings may help guide intraluminal thread selection and flow-restriction strategies during GDD implantation.<\/jats:p>","DOI":"10.3390\/bioengineering13080923","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T15:48:36Z","timestamp":1786722516000},"page":"923","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparative In Vitro Evaluation of Tube Resistance in Glaucoma Drainage Devices with Intraluminal Polypropylene Threads"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-3686-0256","authenticated-orcid":false,"given":"Arief Abdurrazaq","family":"Dharma","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Shimane, Japan"},{"name":"Faculty of Medicine, Universitas Muslim Indonesia, Makassar 90231, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3324-6678","authenticated-orcid":false,"given":"Sachiko","family":"Kaidzu","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Shimane, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-9321-0979","authenticated-orcid":false,"given":"Andi","family":"Masdipa","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Universitas Muslim Indonesia, Makassar 90231, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0443-7694","authenticated-orcid":false,"given":"Virna Dwi Oktariana","family":"Asrory","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia"},{"name":"Cipto Mangunkusumo Hospital, Jakarta 10430, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6512-7203","authenticated-orcid":false,"given":"Masaki","family":"Tanito","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Shimane, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1097\/IIO.0000000000000499","article-title":"Glaucoma Drainage Device Implantation, Outcomes, and Complications","volume":"63","author":"Oatts","year":"2023","journal-title":"Int. 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