{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T02:11:31Z","timestamp":1770948691603,"version":"3.50.1"},"reference-count":15,"publisher":"Korean Ophthalmological Society","issue":"1","license":[{"start":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T00:00:00Z","timestamp":1763337600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["ekjo.org"],"crossmark-restriction":true},"short-container-title":["Korean J Ophthalmol"],"published-print":{"date-parts":[[2026,2,5]]},"abstract":"Purpose: The conventional method for evaluating inferior oblique overaction (IOOA) relies on subjective, qualitative grading. This study aimed to introduce and perform a pilot evaluation of a novel, objective, and quantitative measurement method for IOOA using a newly designed device, the interocular level difference gauge (IOLDG).Methods: Sixty-two consecutive patients (124 eyes) with intermittent exotropia, IOOA or superior oblique palsy were recruited. The degree of IOOA was measured using two methods: (1) the conventional subjective grading scale (+0 to +4) by two examiners (A and B); and (2) the objective IOLDG method by two examiners (C and D). The IOLDG utilizes a spectacle-like frame with a 1 mm-spaced horizontal grid to measure the interocular height difference of the inferior corneal margin in millimeters. Interobserver repeatability was assessed using the paired <i>t<\/i>-test and the intraclass correlation coefficient (ICC).Results: The conventional method showed a statistically significant difference between examiners (paired <i>t<\/i>-test, <i>p<\/i> = 0.002) and moderate repeatability (ICC, 0.749). In contrast, the IOLDG method showed no significant difference between examiners (paired <i>t<\/i>-test, <i>p<\/i> = 0.064) and demonstrated excellent repeatability (ICC, 0.903; <i>p<\/i> < 0.001). The correlation analysis established quantitative equivalents for the conventional grades: grade +1 corresponded to 1.04 \u00b1 0.75 mm, grade +2 to 1.75 \u00b1 0.60 mm, and grade +3 to 2.81 \u00b1 0.75 mm.Conclusions: The IOLDG provides a highly repeatable, objective, and quantitative measurement for IOOA, largely independent of the examiner\u2019s subjective judgment. This simple, chair-side method offers superior reliability compared to the conventional grading scale.<\/jats:p>","DOI":"10.3341\/kjo.2025.0166","type":"journal-article","created":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T00:19:43Z","timestamp":1763425183000},"page":"63-69","update-policy":"https:\/\/doi.org\/10.3341\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Objective Evaluation of Inferior Oblique Overaction Using an Interocular Level Difference Gauge"],"prefix":"10.3341","volume":"40","author":[{"given":"Hong Won","family":"Lee","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Il","family":"Doh","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yeon-Hee","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1893","reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1001\/archopht.1939.00860060109007"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1007\/978-0-387-21753-6_15"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9394(79)90522-1"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9394(74)90381-x"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.1001\/archopht.124.5.680"},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0198002"},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1016\/s0161-6420(89)32774-6"},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9394(72)90313-3"},{"key":"ref9","doi-asserted-by":"publisher","DOI":"10.1186\/s12886-017-0422-6"},{"key":"ref10","doi-asserted-by":"publisher","DOI":"10.3928\/01913913-20110118-04"},{"key":"ref11","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajo.2014.06.016"},{"key":"ref12","doi-asserted-by":"publisher","DOI":"10.1007\/bf02280089"},{"key":"ref13","doi-asserted-by":"publisher","DOI":"10.5935\/0004-2749.20220041"},{"key":"ref14","doi-asserted-by":"publisher","DOI":"10.21037\/qims-22-467"},{"key":"ref15","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajo.2014.07.035"}],"container-title":["Korean Journal of Ophthalmology"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/ekjo.org\/upload\/pdf\/kjo-2025-0166.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/ekjo.org\/journal\/view.php?doi=10.3341\/kjo.2025.0166","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/ekjo.org\/upload\/pdf\/kjo-2025-0166.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T01:28:11Z","timestamp":1770946091000},"score":1,"resource":{"primary":{"URL":"http:\/\/ekjo.org\/journal\/view.php?doi=10.3341\/kjo.2025.0166"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,5]]},"references-count":15,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2026,2]]}},"URL":"https:\/\/doi.org\/10.3341\/kjo.2025.0166","relation":{},"ISSN":["1011-8942","2092-9382"],"issn-type":[{"value":"1011-8942","type":"print"},{"value":"2092-9382","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,5]]},"assertion":[{"value":"2025-11-04","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-11-11","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-11-17","order":2,"name":"published","label":"Published online","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-02-05","order":3,"name":"published","label":"Print publication","group":{"name":"publication_history","label":"Publication History"}}]}}