Gyu Ah Kim1, Si Hyung Lee2, Sang Yeop Lee1, Hee Jung Kwon3, Hyoung Won Bae1, Gong Je Seong1, Chan Yun Kim4. 1. Department of Ophthalmology, Institute of Vision Research, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. 2. Department of Ophthalmology, Bucheon Hospital, Soonchunhyang University, Bucheon, Korea. 3. Department of Ophthalmology, CHA Bundang Medical Center, CHA University, Seongnam, Korea. 4. Department of Ophthalmology, Institute of Vision Research, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. kcyeye@yuhs.ac.
Abstract
PURPOSE: Surgically induced astigmatism (SIA) has attracted much interest in recent times because changes in corneal astigmatism can lead to decreased uncorrected visual acuity and patient discomfort. This study aimed to evaluate SIA and to identify factors correlated therewith after trabeculectomy. METHODS: We retrospectively reviewed medical charts of patients who were treated with trabeculectomy at 120° meridian (superotemporal area on right eye and superonasal area on left eye) by the same surgeon. Preoperative keratometric data were compared with data collected from 2 months to 12 months postoperatively. SIA was evaluated using Naeser's polar value analysis. RESULTS: Using Naeser's method, ΔKP(120) was calculated as 0.7 ± 0.7 (0.82@104°), which indicates a with-the-rule change. After surgery, the combined mean polar values changed significantly (Hotelling T2 = 22.47; p < 0.001). Multivariate analysis of variance indicated that postoperative intraocular pressure and location of surgery were independent factors that were significantly associated with SIA (p = 0.002 and 0.03, respectively). CONCLUSIONS: Trabeculectomy at the 120° meridian was not astigmatically neutral. In addition, the SIA after trabeculectomy appears to be greater in eyes with low postoperative intraocular pressure and a superonasal surgical wound rather than a superotemporal wound.
PURPOSE: Surgically induced astigmatism (SIA) has attracted much interest in recent times because changes in corneal astigmatism can lead to decreased uncorrected visual acuity and patient discomfort. This study aimed to evaluate SIA and to identify factors correlated therewith after trabeculectomy. METHODS: We retrospectively reviewed medical charts of patients who were treated with trabeculectomy at 120° meridian (superotemporal area on right eye and superonasal area on left eye) by the same surgeon. Preoperative keratometric data were compared with data collected from 2 months to 12 months postoperatively. SIA was evaluated using Naeser's polar value analysis. RESULTS: Using Naeser's method, ΔKP(120) was calculated as 0.7 ± 0.7 (0.82@104°), which indicates a with-the-rule change. After surgery, the combined mean polar values changed significantly (Hotelling T2 = 22.47; p < 0.001). Multivariate analysis of variance indicated that postoperative intraocular pressure and location of surgery were independent factors that were significantly associated with SIA (p = 0.002 and 0.03, respectively). CONCLUSIONS: Trabeculectomy at the 120° meridian was not astigmatically neutral. In addition, the SIA after trabeculectomy appears to be greater in eyes with low postoperative intraocular pressure and a superonasal surgical wound rather than a superotemporal wound.
Authors: Ioannis G Pallikaris; George D Kymionis; Harilaos S Ginis; George A Kounis; Miltiadis K Tsilimbaris Journal: Invest Ophthalmol Vis Sci Date: 2005-02 Impact factor: 4.799