{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T09:04:49Z","timestamp":1784624689956,"version":"3.55.0"},"reference-count":50,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: The choice of appropriate intraocular lens (IOL) power calculation formulas depends on the axial length of the eye. This study compares the accuracy of twenty formulas in medium-long eyes (24.50\u201325.99 mm). Methods: Data of patients with medium-long eyes, who underwent uneventful phacoemulsification between January 2018 and September 2023, were retrospectively reviewed. Preoperative IOL power was calculated using the IOLMaster 700 with six formulas: Barrett Universal II, Haigis, Hoffer Q, Holladay 1, Holladay 2, and SRK\/T. Three months postoperatively, refraction was measured. Postoperative IOL power calculations were then performed using fourteen additional formulas: Castrop, EVO 2.0, Hoffer QST, K6, Kane, Karmona, Ladas Super Formula AI (LSF AI), Naeser 2, Olsen (OLCR), Olsen (standalone), PEARL-DGS, T2, VRF CMAL, and VRF-G. The main outcome measures included standard deviation (SD) of the prediction error (PE) and the percentage of eyes with PE within \u00b10.25 D, \u00b10.50 D, \u00b10.75 D, and \u00b11.00 D. Results: Ninety-five eyes with axial lengths ranging from 24.52 mm to 25.97 mm were included. SD values among the twenty formulas ranged from 0.179 (SRK\/T) to 0.468 (Olsen OLCR). The percentage of eyes with PE within \u00b10.50 D ranged from 75.79% (Olsen OLCR) to 98.95% (SRK\/T). The SRK\/T formula, followed by Holladay 1, demonstrated significantly higher accuracy than most other formulas, while Olsen (OLCR) and Castrop were the least accurate. Conclusions: SRK\/T provided the highest accuracy in medium-long eyes, with Holladay 1 performing similarly well. All evaluated formulas achieved PE within \u00b10.50 D in over 74% of cases.<\/jats:p>","DOI":"10.3390\/diagnostics16142281","type":"journal-article","created":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T08:14:27Z","timestamp":1784621667000},"page":"2281","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparative Analysis of Twenty Intraocular Lens Power Calculation Formulas in Medium-Long Eyes"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3919-8339","authenticated-orcid":false,"given":"Wiktor","family":"Stopyra","sequence":"first","affiliation":[{"name":"MW-Med Eye Center, 31-416 Krakow, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5279-2041","authenticated-orcid":false,"given":"Oleksiy","family":"Voytsekhivskyy","sequence":"additional","affiliation":[{"name":"Kyiv Clinical Ophthalmology Hospital Eye Microsurgery Center, 03680 Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrzej","family":"Grzybowski","sequence":"additional","affiliation":[{"name":"Institute for Research in Ophthalmology, Foundation for Ophthalmology Development, 60-836 Poznan, Poland"},{"name":"Department of Ophthalmology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1056","DOI":"10.1136\/bjophthalmol-2021-320997","article-title":"Real-world visual outcomes of cataract surgery based on population-based studies: A systematic review","volume":"107","author":"Han","year":"2023","journal-title":"Br. 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