Anterior Capsule Opening Area Research Articles

Comparison of the stability of 1-piece and 3-piece acrylic intraocular lenses in the lens capsule

To compare the degrees of intraocular lens (IOL) decentration, tilt, and longitudinal movement; the refractive change; and anterior capsule contraction after cataract surgery between eyes with a 1-piece acrylic IOL with soft acrylic loops and eyes with a 3-piece acrylic IOL with rigid poly(methyl methacrylate) loops. Hayashi Eye Hospital, Fukuoka, Japan. Fifty-six patients had implantation of a 1-piece acrylic IOL in 1 eye and a 3-piece acrylic IOL in the fellow eye. The degree of IOL decentration and tilt, the anterior chamber depth (ACD), and the area of anterior capsule opening were measured using Scheimpflug videophotography 3 days and 1, 3, and 6 months postoperatively. The postoperative refractive status was also examined. The mean degrees of decentration and tilt in the 1-piece IOL group were similar to those in the 3-piece IOL group throughout the follow-up. The ACD did not change after surgery in the 1-piece group but showed significant shallowing in the 3-piece group (P < .0001). The spherical equivalent (SE) did not change in the 1-piece group, while the SE had a significant myopic shift of approximately 0.4 diopter in the 3-piece group. The percentage of anterior capsule contraction was similar between the groups. The degree of IOL decentration and tilt and percentage of anterior capsule contraction in eyes with a 1-piece acrylic IOL with soft acrylic loops were similar to those in eyes with a 3-piece acrylic IOL. The longitudinal movement of the 1-piece IOL was less than the movement of the 3-piece IOL, resulting in less postoperative myopic shift.

Intraocular lens factors that may affect anterior capsule contraction

To examine the various factors comprising intraocular lenses (IOLs) that may affect the degree of anterior capsule contraction after cataract surgery. Randomized controlled clinical trials. Three hundred thirty-one patients scheduled for bilateral cataract surgery were studied to compare the degree of anterior capsule contraction in fellow eyes that received different IOLs with regard to the following factors: (1) optic material-acrylic optic versus silicone optic; (2) optic design-round-edge optic versus sharp-edge optic; (3) haptic material-polymethyl methacrylate (PMMA) loop versus polyvinylidene fluoride loop; and (4) haptic material and design-single-piece acrylic haptic versus 3-piece PMMA haptic. The 2 IOLs implanted in the fellow eyes of each patient had almost the same material and design, except for the specific factor being compared. All patients underwent phacoemulsification surgery with implantation of different IOLs in fellow eyes. The area of the anterior capsule opening was measured using the Scheimpflug videophotography system at 3 days or 1 week (baseline) and at 1, 3, and 6 months after surgery. The percent reduction in the anterior capsule opening area from baseline was determined at 1, 3, and 6 months after surgery. The mean percent reduction of the anterior capsule opening area was significantly greater in eyes with a silicone optic IOL than in eyes with an acrylic optic IOL. However, no significant difference was observed in the percent reduction between round-edge and sharp-edge optic IOLs, between PMMA and polyvinylidene fluoride loop IOLs, and between single-piece acrylic and 3-piece PMMA haptic IOLs. Strong associations were found in the percentage between round-edge and sharp-edge optic IOLs, between PMMA and polyvinylidene fluoride loop IOLs, and between single-piece acrylic and 3-piece PMMA haptic IOLs, whereas there was a relatively weak association between silicone and acrylic optic IOLs. Among the IOL factors examined, optic material affects most significantly the degree of anterior capsule contraction, whereas optic design and haptic material and design are not strongly related to anterior capsule contraction.

Relationship between anterior capsule contraction and posterior capsule opacification after cataract surgery in patients with diabetes mellitus

Purpose: To prospectively assess the relationship between contraction of the anterior capsule opening and posterior capsule opacification (PCO) after cataract surgery in patients with diabetes mellitus. Setting: Department of Ophthalmology, University of Tokyo School of Medicine, Tokyo, Kaiya Eye Clinic, Hamamatsu, and Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Ibaragi, Japan. Methods: This study comprised 45 patients (45 eyes) with diabetes mellitus who had cataract surgery. In all eyes, the anterior capsule opening area and degree of PCO were determined by diaphanoscopy using an anterior eye segment analysis system (EAS-100, Nidek, Inc.) 1 day and 1 year postoperatively. Results: There was no correlation between the size of the anterior capsule opening area 1 day after surgery and the degree of PCO 1 year after surgery (Pearson correlation coefficient [ r] = 0.041; P = .79). The percentage reduction in the anterior capsule opening area from 1 day to 1 year after surgery did not correlate with the degree of PCO 1 year after surgery ( r = −0.08; P = .60). Conclusion: Contraction of the anterior capsule opening and PCO after cataract surgery cannot be explained by a common mechanism.

Risk factors for contraction of the anterior capsule opening after cataract surgery

Purpose: To investigate the factors contributing to contraction of the anterior capsule opening (ACO) after cataract surgery in normal eyes. Setting: Department of Ophthalmology, University of Tokyo, School of Medicine, Tokyo, and Kaiya Eye Clinic, Hamamatsu, Japan. Methods: This study included 141 eyes of 141 patients scheduled to have cataract surgery. The area of the ACO was determined by diaphanoscopy using the EAS-1000 anterior eye segment analysis system 1 day and 9 months postoperatively, after which the percentage reduction in the ACO area was calculated. Aqueous flare intensity was measured with a laser flare-cell meter 1 week and 9 months after surgery. Multiple regression analysis was performed to determine which factors were correlated with the percentage reduction in the ACO area. Variables tested included patient age, axial length, the ACO area on the first postoperative day, and flare values 1 week and 9 months after surgery. Results: Patient age ( r = 0.193, P = .029) and flare intensity 9 months after surgery ( r = 0.255, P = .007) were significantly correlated with the percentage reduction in the ACO area ( R 2 = 0.133). The axial length, ACO area 1 day postoperatively, and flare value at 1 week were not correlated with ACO contraction. Conclusion: Contraction of the ACO after cataract surgery is related to instability of the blood-aqueous barrier.

Anterior capsule contraction and intraocular lens dislocation in eyes with pseudoexfoliation syndrome

AIMSTo examine the extent of anterior capsule contraction as well as intraocular lens (IOL) decentration and tilt following implant surgery in eyes with pseudoexfoliation syndrome (PE).METHODS53 eyes from 53 patients...

Area reduction in the anterior capsule opening in eyes of diabetes mellitus patients

Purpose: To compare the extent of area reduction in the anterior capsule opening after continuous curvilinear capsulorhexis in the eyes of diabetes mellitus (DM) patients with that in the eyes of patients without DM.Setting: Hayashi Eye Hospitai, Fukuoka, Japan.Methods: Ninety-one eyes of 91 DM patients and 91 age-matched eyes of patients without DM (control group) having intraocular lens (IOL) implantation were recruited for this prospective study The DM group comprised 36 eyes with diabetic retinopathy (DR) and 55 without retinopathy (NDR). The anterior capsule opening area was quantitated using Scheimpflug photography 1 week and 1, 3, and 6 months postoperativelyResults: There was no statistically significant difference in mean anterior capsule opening area between the DM and control groups at 1 week or, 1 month postoperatively, The area was significantly, smaller in the DM group at 3 (P = .0221) and 6 (P = .0075) months. The percentage area reduction was also greater i6 the DM group than in the control group. The area in the DR group was significantly smaller than in the control group at 3 (P = .0392) and 6 (P = .0080) months. The percentage reduction in the DR group was larger than in the NDR or control group.Conclusions: After IOL implantation, contraction of the anterior capsule opening area was more extensive in eyes of DM patients than in those of patients without DM, especially in the case of DR.

Reduction in the Area of the Anterior Capsule Opening After Polymethylmethacrylate, Silicone, and Soft Acrylic Intraocular Lens Implantation

To report reduction in the area of anterior capsule opening at various postoperative intervals after continuous capsulorrhexis and to compare any differences in the area reduction between polymethylmethacrylate, silicone, and soft acrylic intraocular lenses. Prospectively, 240 eyes of 240 patients undergoing phacoemulsification and intraocular lens implant surgery were randomized into three groups based on the type of intraocular lens used: polymethylmethacrylate, silicone, and soft acrylic. The area of the anterior capsule opening was quantitated, and examinations were performed at 1 week and 1, 3, and 6 months postoperatively. After intraocular lens implantation, the mean anterior capsule opening area 3 months postoperatively was significantly smaller than that at 1 week in all groups (polymethylmethacrylate, P = .0090; silicone, P < .0001; soft acrylic, P = .0127). Mean percentages in area reduction at both 3 and 6 months postoperatively were significantly greater than those at 1 week and 1 month (P < .0001). In comparing the three intraocular lenses at 1 week postoperatively, no statistical significance was observed regarding the anterior capsule opening area between the three groups. However, the mean anterior capsule opening areas in the polymethylmethacrylate and soft acrylic intraocular lens groups were significantly larger than those in the silicone intraocular lens group at 1 month (P = .0024), and 3 months (P = .0032), and 6 months (P = .0022) postoperatively. After continuous capsulorrhexis and intraocular lens implant surgery, the area of the anterior capsule opening gradually decreased for up to 3 months postoperatively. The contraction of the anterior capsule opening was greater in the silicone group than in either the polymethylmethacrylate or the soft acrylic groups.