Changes in symmetry of anterior chamber following routine cataract surgery in non-glaucomatous eyes.

BACKGROUND: To assess minimum and maximum changes in anterior chamber dimensions following routine cataract surgery in non-glaucomatous eyes. METHODS: Forty-two eyes (42 participants) underwent routine cataract surgery with same surgeon and were assessed preoperatively, 1, 3, 6 and 12 months postoperatively. Primary outcome measure: Angle-to-angle diameter (AAD) (at 0-180o, 45-225o, 90-270o, 135-315o), Anterior-chamber-angle (ACA) (at 0o, 45o, 90o, 135o, 180o, 225o, 270o and 315o) and central anterior chamber depth (ACD) at all visits. Secondary outcome measures: relationship to axial length (AL). RESULTS: The mean AAD and ACA increased post-operatively in all meridians at all visits postoperatively. At 12 months, there was a maximum change in AAD in horizontal meridian (506.55 ± 468.71 µm) and least in vertical meridian (256.31 ± 1082.3 µm). The mean percentage increase in ACA postoperatively was least at 90o (5% increase compared to 29-35% elsewhere). Central ACD deepened at all postoperative visits and this did not change over 12 months. There was no correlation between AAD, ACA and ACD with AL at any visit. CONCLUSION: The AAD, ACA and ACD increases following cataract surgery in non-glaucomatous eyes, but at 12 months increase in AAD is least in vertical compared to horizontal meridian. Also, ACA was narrower (only 5% increase) superiorly compared to elsewhere (29-35% increase in ACA). This may have implications with regards to surgeries performed in the anterior chamber and corneal endothelial cell loss.

Edge profile of commercially available square-edged intraocular lenses: Part 2.

PURPOSE: To analyze the sharpness of the posterior optic edge and edge thickness of intraocular lenses (IOLs) marketed with a square-edged profile. SETTING: University of Brighton and Brighton and Sussex University Hospitals NHS Trust, Brighton, England. DESIGN: Laboratory study. METHODS: Fourteen square-edged 20.0 diopter IOLs were analyzed, including 9 hydrophobic IOLs (AF-1, AF-1 iSert, Clareon, EyeCee One Crystal, CT Lucia, Envista, EyeCee One, Vivinex iSert, and RayOne Hydrophobic) and 5 hydrophilic IOLs (Asphira, CT Asphina, Incise, Synthesis, and RayOne Hydrophilic). All the IOLs were scanned following a previously published standardized technique using environmental scanning electron microscopy. The posterior optic edges were scanned at a magnification of ×500 and ×200 to measure the radius of curvature of the posterior optic edges and the optic edge thickness. RESULTS: The radius of curvature of the posterior optic edges ranged from 4.6 to 20.6 µm. Except for the Incise IOL (7.7 µm), all hydrophilic IOLs (Synthesis [10.6 µm], Asphira [13.7 µm], RayOne Hydrophilic [14.0 µm], CT Asphina [13.7 µm]) had a radius of curvature greater than 10.0 µm. For the hydrophobic IOLs, the radius of curvature was less than 10.0 µm for the Clareon (7.9 µm), EyeCee One Crystal (4.7 µm), Vivinex iSert (7.6 µm), and CT Lucia (4.6 µm), and greater than 10.0 µm for the Envista (19.7 µm), EyeCee One (13.7 µm), AF-1 iSert (19.7 µm), AF-1 (19.7 µm) and the RayOne Hydrophobic (20.6 µm). The Vivinex iSert (150.5 µm) and the Incise (218.2 µm) were the thinnest IOLs, and the RayOne Hydrophobic (375.8 µm) and RayOne Hydrophilic IOLs (477.1 µm) were the thickest of the hydrophobic and hydrophilic IOLs, respectively. CONCLUSIONS: Commercially marketed square-edged IOLs still differed in the sharpness of the posterior optic edge. More hydrophobic IOLs have rounder edges than those studied 10 years ago. Variations in the edge profile of hydrophobic IOLs were greater compared with the hydrophilic IOLs.

Influence of peripheral corneal relaxing incisions during cataract surgery for corneal astigmatism up to 2.5 dioptres on corneal densitometry.

PURPOSE: To assess the effect of peripheral corneal relaxing incisions (PCRI) for astigmatism between 0.75 and 2.5 dioptres during cataract surgery on corneal densitometry (CD). METHODS: In this prospective, randomised study, 80 eyes (80 patients), received either tIOL or PCRI. Assessment at pre-operative and 1, 3, 6, 12 months post-operative visit included uncorrected (UCDVA) and best-corrected distance visual acuity (BCDVA), spherical equivalent (SEQ) (only post-operatively), mean anterior and posterior keratometric astigmatism (KA) and CD with Schiempflug system. CD was analysed in four concentric radial zones from centre to periphery (Zone 1 to 4) and in 3 layers (anterior, mid-stromal and posterior). RESULTS: Comparing tIOLs vs. PCRIs, there was no significant difference in the UCDVA, BCDVA and SEQ. In PCRI group, anterior KA decreased at 1 month and remained stable thereafter. For zones 1, 2 and 3, CD significantly reduced after 3 months with tIOLs whereas with PCRIs, it reduced 1 month onwards. For zone 4, CD reduced only at 12 months with tIOLs compared to 3 months onwards with PCRIs. In both groups CD was higher in the zone 4 and anterior layer. Significant reduction in CD was found in all three layers of cornea after 3 months in tIOL and after first month in PCRI groups, respectively. CONCLUSIONS: Cataract surgery alone reduces the CD. Reducing keratometric astigmatism with PCRIs shows significant differences in CD from early post-operative period for central and anterior corneal layer.