An anterior segment optical coherence tomography study of the anterior chamber angle after implantable collamer lens-V4c implantation in Asian Indian Eyes

Abstract

Purpose: To quantitatively assess anterior chamber and angle parameters by anterior segment optical coherence tomography (AS-OCT) in myopic eyes undergoing Implantable Collamer Lens (ICL V4c) implantation. Methods: Prospective noncomparative observational case series. Pre and postoperative (1 st and 3 rd month) AS-OCT angle parameters (anterior chamber depth [ACD], anterior chamber angle [ACA], Angle opening distance [AOD], trabecular iris space area [TISA], scleral spur angle [SSA]) were evaluated in 32 eyes (16 patients). SPSS version 20 with paired t -test for intragroup and Mann-Whitney U value test for intergroup comparisons. Results: It included 6 (37.5%) males and 10 (62.5%) females. Preoperative ACA of 34.6 ± 2.3° reduced to 32.2 ± 2.4°, 31.9 ± 2.5° at 1 and 3 months postoperatively ( P = 0.001). Preoperative mean AOD500, AOD750, TISA500, TISA750, SSA of 0.34 ± 0.06 mm, 0.52 ± 0.15 mm, 0.09 ± 0.02 mm 2 , 0.20 ± 0.04 mm 2 , 34.27 ± 4.6° decreased to 0.32 ± 0.06 mm, 0.48 ± 0.15 mm, 0.08 ± 0.02 mm 2 , 0.17 ± 0.05 mm 2 , 32.5 ± 4.3° at 1-month ( P = 0.001); 0.32 ± 0.06 mm, 0.47 ± 0.13 mm, 0.08 ± 0.02 mm 2 , 0.17 ± 0.05 mm 2 and 32.4 ± 4.6° ( P = 0.001) at 3-months, respectively. Correlation analysis between preoperative ACD/intraocular pressure (IOP) was − 0.62 ( P = 0.0002) [1 st month], −0.40 (0.024) [third month]; between IOP/postoperative ACA, AOD500, AOD750, TISA500, TISA750, SSA was − 0.04 (0.81), −0.03 (0.85), −0.08 (0.64), −0.12 (0.48), −0.10 (0.57), −0.06 (0.73) at 1 month; −0.09 (0.58), 0.04 (0.78), 0.12 (0.48), −0.02 (0.9), −0.04 (0.79), 0.02 (0.88) at 3 months; between ICL vault/ACA, AOD500, AOD750, TISA500, TISA750, SSA was 0.38 (0.02), 0.24 (0.17), 0.21 (0.25), 0.05 (0.75), 0.15 (0.41), 0.27 (0.13) at 1 st month; 0.19 (0.28), 0.06 (0.71), −0.03 (0.85), 0.005 (0.97), 0.05 (0.78), 0.07 (0.68) at 3 rd month. Conclusion: Postoperatively significant angle narrowing was noted. There was a negative correlation between IOP and preoperative ACD. There was no significant correlation between IOP and ICL vault with postoperative AS-OCT angle parameters.

Regional Variations in Corneal Epithelial Cell Density and Morphology Assessed Using In Vivo Confocal Microscopy

“…Contrary to previous reports [6][7][8][9][10][11][12][13][14] of the observed highest cell densities in the peripheral cornea, this study found the cell densities (both BCD and WCD) were lowest at the 9-mm peripheral ring (including inferior, nasal, superior, and temporal quadrants; Fig. 3).…”

“…However, it is easier to image the central cornea using IVCM than the peripheral cornea, and this is reflected in the literature. Most studies describe central corneal epithelial cell morphology (mostly cell density and size), [6][7][8][9][10][11][12][13][14] with very few studies of the peripheral cornea. 6,7,13,14 Exact peripheral locations (relative to the corneal apex) are typically not stated.…”

Clinical Observation of Posterior-Chamber Phakic Implantable Collamer Lens V4c Implantation in Myopic Patients with Shallow Anterior Chamber Depth: A Retrospective, Consecutive Observational Study

“…The IOP is also crucial after ICL implantation. The IOP is negatively correlated with the preoperative ACD but still within the normal range, as reported by Vanathi et al [ 23 ]. In our study, there was no significant correlation between preoperative ACD and postoperative IOP, probably because of the narrow range of our ACD.…”

Toric Implantable Collamer Lens for the Treatment of Myopic Astigmatism

“…Bioptics may play a role to refine refraction after Toric ICL as was seen in our eleven patients who underwent enhancements. Most eyes were implanted with a 12.6 mm Toric ICL in the present study, compared with an average implantation size of 13.2 mm in another study, 29 suggesting that the 13.7 mm lens size is infrequently utilized. Sheng et al suggest that undersized Toric ICLs, resulting in low vault, are more susceptible to rotation.…”