{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T16:37:59Z","timestamp":1790181479349,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,4,9]],"date-time":"2025-04-09T00:00:00Z","timestamp":1744156800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Objectives: To estimate the efficacy of the eight-chop technique in phacoemulsification surgeries for patients with hard nucleus cataracts by investigating the reduction of corneal endothelial cell density (CECD) after phacoemulsification and intraoperative parameters. Methods: Patients were categorized into three groups (Grade IV, IV plus, and V) according to the hardness of their lens nuclei. Surgeries were performed using the eight-chop technique. Key intraoperative metrics (operative time, phaco time, aspiration time, cumulative dissipated energy [CDE], and fluid volume used) were measured. Pre- and postoperative assessments included corrected-distance visual acuity, intraocular pressure (IOP), central corneal thickness, variation in the size of the endothelial cells, percentage of hexagonal cells, and CECD. Results: Overall, 89 eyes from 67 patients with cataracts were evaluated. The mean operative time, phaco time, aspiration time, CDE, and fluid volume used across Grades IV, IV plus, and V were 10.5 min, 38.9 s, 135.6 s, 19.2, and 53.0 mL, respectively. At 19 weeks postoperatively, the CECD decreased by 0.2%, 6.8%, and 9.6% for Grades IV, IV plus, and V, respectively, with an average decrease of 3.7%. Significant reductions in postoperative IOP were observed across all groups compared with preoperative IOP (p &lt; 0.01). Loss of CECD significantly correlated with phaco time, CDE, and fluid volume (p = 0.027, p &lt; 0.01, and 0.034, respectively). Conclusions: The eight-chop technique in phacoemulsification for hard nucleus cataracts resulted in minimal CECD loss. It may provide an effective surgical solution for patients with hard nucleus cataracts.<\/jats:p>","DOI":"10.3390\/jcm14082576","type":"journal-article","created":{"date-parts":[[2025,4,9]],"date-time":"2025-04-09T05:03:07Z","timestamp":1744174987000},"page":"2576","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Minimizing Endothelial Cell Loss in Hard Nucleus Cataract Surgery: Efficacy of the Eight-Chop Technique"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6255-8745","authenticated-orcid":false,"given":"Tsuyoshi","family":"Sato","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Sato Eye Clinic, 3-3 Nemoto, Matsudo-shi 271-0077, Chiba-ken, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1016\/j.jcrs.2018.03.038","article-title":"Phacoemulsification of the rock-hard dense nuclear cataract: Options and recommendations","volume":"44","author":"Foster","year":"2018","journal-title":"J. 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