Quantification of an oval optic disc in relation to myopic foveoschisis using swept-source optical coherence tomography.

BACKGROUND: To investigate the relationship between an oval optic disc and the occurrence of myopic foveoschisis (MF) using swept-source optic coherence tomography (SS-OCT). METHODS: Fifty eyes of 25 patients with unilateral MF were included in this retrospective observational study. The biometric features of the optic disc and peripapillary structures were evaluated using SS-OCT. RESULTS: The ovality index (OI) of the optic disc was significantly smaller (P = 0.003) and the optic disc tilt angle was greater (P = 0.023) in the eyes with MF than in the contralateral eyes. The optic disc tilt angle was significantly correlated with the OI (P = 0.000). Generalized estimating equation (GEE) model (linear regression) demonstrated that spherical equivalent refraction (P = 0.001), narrow macular staphyloma (P = 0.001) and the occurrence of MF (P = 0.026) were the independent factors associated with the OI. Narrow macular staphyloma was more frequent (P = 0.020) and the staphyloma was deeper (P = 0.006) in eyes with MF. GEE model (logistic regression) revealed that narrow macular staphyloma was the only independent factor related to the occurrence of MF (P = 0.013). CONCLUSIONS: An oval optic disc in eyes with MF resulted from the increased tilt around the vertical disc axis. The optic disc tilt was related to narrow macular staphyloma, which was the only independent factor associated with the occurrence of MF. The clinical relevance needs further exploration through longitudinal analysis.

Evaluation of 82 Cases of Oval Optic Intraocular Lens Implanted in the Bag

The postoperative results of 77 paients:(82 eyes) who had undergone phacoemulsification with implantation of oval optic poly methylmethacrylate (PMMA) introoular intraowlar lens (IOL) (5 X 6mm) were evaluated retrospectively. Scleral pocket incision was done tangentially at the point 2mm. apart from the surgical limbus and 5mm in length. No suture in the group 1 (30 eyes), single horizontal suture in the group 2 (31 eyes) and single X suture in the group 3 (21 eyes) were used for the closure method. Average uncorrected visual acuity at postoperative one week was 0.5 or better in each group and there was no statistically significant difference among three groups (p>0.05). The change in mean keratometric astigmatism from postoperative one to eight weeks turned out to be less than 1 diopter (D) in each group and there was no statistically significant difference among three groups (p>0.05). When the diameter of continuous cirular capsulorhexis (CCC) was greater than 5mm or the position of CCC was decentered, it was found that optic was partially escaped form the bag due to adhesion between the remained anterior and posterior capsular structure. It could be suggested that oval optic PMMA IOL showes early visual recovery with less astigmatism regardless of the suture method and in order to place the optic of IOL properly in the bag postoperatively, the diameter of CCC should be less than 5mm and the position of CCC should be centered.