Degree Of Posterior Capsule Opacification Research Articles

Correlations of single nucleotide polymorphisms of CRYAA and CRYAB genes with the risk and clinicopathological features of children suffering from congenital cataract.

Background:The study aims to explore the correlations of the single nucleotide polymorphisms (SNPs) of CRYAA and CRYAB with the risk and clinicopathological features of children with congenital cataract.Methods:The study enrolled 168 children diagnosed as congenital cataract (case group) and 172 normal children (control group) from May 2015 to May 2016. Genomic DNA extraction was performed using a QIAamp DNA blood mini kit. Polymerase chain reaction (PCR) products were genotyped using an ABI direct sequencer. Haplotype, allele, and genotype frequencies of CRYAA and CRYAB gene polymorphisms analyses were carried out using the SHEsis software. Logistic regression analysis was performed in order to analyze the risk factors for children suffering from congenital cataract.Results:Presence of significant differences between the case and control groups’ genotype and allele frequencies of CRYAA rs7278468 and CRYAB rs370803064/rs387907338. TA of CRYAB gene might increase congenital cataract risk in children, while GCG of CRYAA gene and GC of CRYAB gene might decrease congenital cataract risk in children. CRYAA rs7278468, CRYAB rs370803064/rs387907338 polymorphisms were significantly correlated to uncorrected visual acuity, best-corrected visual acuity, nystagmus, visual axis opacification, microcornea, lens opacity, posterior capsular thickening, and degrees of posterior capsule opacification after operation in children with congenital cataract. Logistic regression analysis revealed that the T allele of CRYAA rs7278468, A allele of CRYAB rs370803064, T allele of CRYAB rs387907338, family history, and TA haplotype of CRYAB gene were risk factors for children with congenital cataract.Conclusion:Our findings demonstrated that CRYAA rs7278468 and CRYAB rs370803064/rs387907338 are correlated with the risk and clinicopathological features of children suffering from congenital cataract.

UV-assisted treatment on hydrophobic acrylic IOLs anterior surface with methacryloyloxyethyl phosphorylcholine: Reducing inflammation and maintaining low posterior capsular opacification properties

In order to enhance the surface biocompatibility of hydrophobic acrylic intraocular lenses (IOLs), the anterior surface was modified through graft polymerization with methacryloyloxyethyl phosphorylcholine (MPC) initiated by ultraviolet radiation. Chemical changes on the IOL surface were characterised by X-ray photoelectron spectroscopy (XPS) to confirm the covalent binding of MPC. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) analysis were used to characterise the morphological changes to the IOL surface. Static water contact angle (WCA) measurements showed that the hydrophilicity of the anterior surface was enhanced after grafting with MPC. The surface biocompatibility of the untreated and Anterior UV-MPC IOLs was compared with the adhesion behaviour of macrophages in vitro. The degree of posterior capsule opacification (PCO) of untreated, anterior treated, and posterior treated IOLs was evaluated by observing the behaviour of lens epithelial cells (LECs) between the IOL optic portion and type IV collagen. Results suggest that the MPC modified anterior surface resisted the attachment of macrophages. However, MPC grafted onto the posterior surface enhanced the migration of LECs between the IOL optic and type IV collagen, which may result in severe PCO. In conclusion, our Anterior UV-MPC IOLs may reduce postoperative inflammation while maintaining the low PCO rates of hydrophobic acrylic IOLs.

Comparison of stability of acrylic intraocular lens and transparency of lens capsule using Pentacam Scheimpflug System

To compare the amounts of intraocular lens (IOL) decentration and tilt, the anterior chamber depth (ACD) and the degree of posterior capsule opacification (PCO) using the Pentacam Scheimpflug System after cataract surgery between eyes with 1-piece acrylic IOL and 3-piece acrylic IOL. It was a perspective study. Fifty-one patients with bilateral senile cataract had implantation of a 1-piece SA60AT IOL in one eye and a 3-piece MA60BM IOL in the contralateral eye. The amount of IOL decentration, tilt, the ACD, and the degree of PCO was measured using the Pentacam Scheimpflug System 1 day and 1, 6, 12 and 24 months postoperatively. There were no significant changes during the 24 m follow-up period in the decentration (0.37 ± 0.16, 0.36 ± 0.15, 0.36 ± 0.16, 0.37 ± 0.15, 0.38 ± 0.16), tilt (3.59 ± 0.91, 3.64 ± 0.92, 3.61 ± 0.90, 3.63 ± 0.90, 3.70 ± 0.89) or PCO (22.20 ± 3.99, 21.96 ± 4.00, 22.40 ± 4.03, 22.53 ± 4.00, 22.95 ± 3.87) in the 1-piece SA60AT group (F = 1.938, 0.785, 1.814; P > 0.05) or in the 3-piece MA60BM group (0.34 ± 0.14, 0.33 ± 0.14, 0.34 ± 0.14, 0.35 ± 0.14, 0.36 ± 0.14), (3.55 ± 0.90, 3.57 ± 0.92, 3.63 ± 0.88, 3.61 ± 0.88, 3.65 ± 0.89), (21.14 ± 3.88, 20.98 ± 3.87, 21.23 ± 3.83, 21.59 ± 3.82, 21.65 ± 3.87) (F = 1.004, 0.525, 1.963; P > 0.05). There was no significant difference between the two groups in IOL decentration (t = 0.802, 0.701, 0.588, 0.898, 0.631), tilt (t = 0.199, 0.337, 0.094, 0.121, 0.248) or PCO (t = 1.214, 1.119, 1.334, 1.082, 1.517) at any time points (P > 0.05). The ACD did not change after the surgery in the 1-piece group (3.90 ± 0.99, 3.88 ± 1.07, 3.91 ± 1.01, 3.90 ± 1.02, 3.92 ± 1.02) (F = 1.333, P > 0.05) but was significantly deeper in the 3-piece group (4.37 ± 1.02, 3.90 ± 0.98, 3.95 ± 0.99, 3.93 ± 0.96, 3.97 ± 0.99) (F = 92.757, P < 0.05) one day after the operation. The ACD was more shallow in the 1-piece SA60AT group than in the 3-piece MA60BM group at all time points. However, the difference was statistically significant only at 1 day after surgery (t = 102.944, P < 0.05). The degrees of IOL decentration, tilt, ACD and PCO in eyes with a 1-piece acrylic IOL with flexible haptics implanted in the capsular bag were similar to those in eyes with a 3-piece acrylic IOL with rigid PMMA haptics. But the 1-piece acrylic IOL provides a better stability than the 3-piece acrylic IOL in the early stage postoperatively.

Three-Year Follow-up of Posterior Capsule Opacification After AquaLase and NeoSoniX Phacoemulsification

To prospectively compare the degree of posterior capsule opacification (PCO) after AquaLase and NeoSoniX phacoemulsification methods during the 3-year follow-up period. Prospective, randomized clinical trial. Setting at the Department of Ophthalmology, University Hospital in Hradec Králové. Patients with bilateral cataract were included. AquaLase was used in the right eye and NeoSoniX in the left eye of each patient. The AcrySof SA60AT intraocular lens (Alcon Laboratories, Fort Worth, Texas, USA) was implanted in all eyes. The Evaluation of Posterior Capsule Opacification (EPCO) 2000 software (Developed by Tetz MR and associates, Berlin, Germany) and the Open-Access Systematic Capsule Assessment (OSCA) system (Devised by Aslam TM, Edinburgh, United Kingdom) were used for PCO assessment 1, 2, and 3 years after cataract surgery. Fifty patients were analyzed 1 year, 47 patients 2 years, and 46 patients 3 years after cataract surgery. Mean EPCO 2000 values were for the AquaLase group 0.324 +/- 0.305 and for the NeoSoniX group 0.298 +/- 0.341 (P = .53) 1 year after surgery, for the AquaLase group 0.429 +/- 0.322 and for the NeoSoniX group 0.478 +/- 0.337 (P = .30) 2 years after surgery, and for the AquaLase group 0.582 +/- 0.506 and for the NeoSoniX group 0.594 +/- 0.515 (P = .87) 3 years after surgery. The OSCA results were for the AquaLase group 0.7097 +/- 0.3778 and for the NeoSoniX group 0.8584 +/- 0.4323 (P = .046) 1 year after surgery, for the AquaLase group 0.7515 +/- 0.4555 and for the NeoSoniX group 0.8103 +/- 0.4498 (P = .44) 2 years after surgery, and for the AquaLase group 0.9667 +/- 0.736 and for the NeoSoniX group 0.9540 +/- 0.5250 (P = .91) 3 years after surgery. Neodymium-yttrium-aluminun-garnet capsulotomy rate for AquaLase vs NeoSoniX was 0:1 eyes 1 year, 1:3 eyes 2 years, and 1:4 eyes 3 years after surgery. No significant difference between those 2 groups was established, except the OSCA outcomes 1 year postoperatively. There was only minimal PCO difference between these 2 approaches, AquaLase and NeoSoniX. Neither AquaLase nor NeoSoniX technique was able to prevent a natural progression of PCO.

Intraindividual Comparison of Aspherical and Spherical Intraocular Lenses of Same Material and Platform

There have been few studies which compared aspherical and spherical intraocular lenses (IOLs) of same material and platform in bilateral cataract cases. We performed an intraindividual comparison of ocular aberration and scotopic, mesopic, and photopic contrast sensitivity with aspherical and spherical IOLs, using the same IOL material and platform manufactured by the same company. Prospective, randomized, controlled study. Eighty-two eyes of 41 patients undergoing bilateral cataract surgery. One eye of a patient was assigned to acrylic foldable aspherical IOL (Tecnis ZA9003, Advanced Medical Optics), and the contralateral eye was allocated to acrylic foldable spherical IOL (AR40e, Advanced Medical Optics). All patients were examined at 2 days, 1 week, and 1 month postoperatively. Best-corrected visual acuity (BCVA), contrast sensitivity under scotopic (15 lux), mesopic (70 lux), and photopic (180 lux) conditions, corneal and ocular wavefront aberrations, anterior chamber depth, amount of IOL decentration and tilt, pupil diameter under scotopic (3 lux) and photopic (250 lux) conditions, area of anterior capsule opening, degree of posterior capsule opacification, and all-distance visual acuity. There was no significant difference between IOLs in BCVA, anterior chamber depth, amount of IOL decentration and tilt, pupil diameter, area of anterior capsule opening, and degree of posterior capsule opacification. In corneal wavefront aberrations, there was no difference in 3rd-, 4th-, and total higher-order root-mean-square (RMS). In ocular wavefront aberration, aspherical IOL showed significantly lower 4th-order (P<0.001) and total higher-order RMS (P<0.001) than spherical IOL, but not in 3rd-order RMS (P = 0.103). Contrast sensitivity under scotopic conditions was significantly better with aspherical IOL than with spherical IOL at 3 (P = 0.0015), 6 (P = 0.0192), and 12 cycles per degree (P = 0.0315). Contrast sensitivity under mesopic and photopic conditions was not significantly different between IOLs. There was no between-group difference in visual acuity at 0.3, 0.5, 0.7, 1.0, or 5.0 meters measured with full distance correction. Acrylic foldable aspherical IOL (Tecnis ZA9003) yielded significantly lower ocular wavefront aberration and better contrast sensitivity under scotopic condition without compromising depth of focus. The authors have no proprietary or commercial interest in any materials discussed in this article.

One-Year Prospective Intrapatient Comparison of Aspherical and Spherical Intraocular Lenses in Patients with Bilateral Cataract

To conduct longitudinal, intrapatient comparisons of aspherical and spherical silicone intraocular lenses (IOL) of the same material and platform in patients undergoing bilateral cataract surgery. Prospective, randomized study. Sixty-two eyes of 31 patients were randomized to receive a silicone aspherical IOL (Tecnis Z9000; AMO Inc, Santa Ana, California, USA) in 1 eye and a silicone spherical IOL (CeeOn 911A; AMO Inc) in the other eye. Best spectacle-corrected visual acuity (BSCVA); corneal and ocular wavefront aberrations; contrast sensitivity under photopic (180 lux), intermediate (75 lux), and scotopic (15 lux) illumination; amount of IOL decentration and tilt; and degree of posterior capsular opacification were measured at 1, 3, 6, and 12 months after surgery. All-distance visual acuity (VA) was measured 3 months after surgery. There were no significant differences between IOLs with regard to BSCVA, amount of IOL decentration and tilt, degree of posterior capsule opacification, and all-distance VA at any point after surgery. Regarding corneal wavefront aberrations, there was no difference in third- and fourth-order root mean square (RMS). In ocular wavefront aberrations, aspherical IOLs showed significantly lower fourth-order RMS (P < .001) than spherical IOLs throughout the study, but not in third-order RMS. Contrast sensitivity under photopic and mesopic conditions was not different between IOLs, but contrast sensitivity under scotopic conditions was significantly better with aspherical IOLs than with spherical IOLs (P < .01) at all measurement points. The silicone aspherical IOL (Tecnis Z9000; AMO Inc) significantly reduced ocular spherical aberration and improved scotopic contrast sensitivity, and these results were consistent through the 1-year follow-up.

Comparison of posterior capsule opacification in rabbits receiving either mitomycin‐C or distilled water for sealed‐capsule irrigation during cataract surgery

To compare posterior capsule opacification (PCO) in rabbits who undergo cataract surgery and receive either mitomycin-C (MMC) or distilled water (DW) during sealed-capsule irrigation (SCI). In addition, we examined the toxicity of DW and MMC. Twenty-four eyes from 12 rabbits were divided into three groups. Balanced salt solution (BSS), DW, MMC 0.4 mg/mL was injected into the capsular bag for 2 min after endocapsular phacoemulsification and insertion of a SCI device. The degree of PCO was assessed by POCOman software at 3 months post surgery. Central corneal thickness, anterior chamber inflammation were assessed 1 day, 1 week, 2 weeks, 3 weeks, 1 month and 3 months postoperatively. A statistically significant difference in PCO scores was noted between the control and study groups (P < 0.05). The PCO scores of the MMC group were significantly lower than those of the DW group (P < 0.05). The MMC and DW groups did not show significant toxicity compared with the BSS group. MMC is more effective in reducing PCO than DW; the SCI device can protect the surrounding ocular tissue from MMC toxicity in rabbit eyes.

Quantitative Analysis of Posterior Capsule Opacification of Hydrophobic Acrylic Intraocular Lenses

Posterior capsule opacification (PCO) remains a common complication of modern cataract surgery, although both modification of materials used and changes in the intraocular lens (IOL) optic edge design have helped to decrease its incidence slightly. Recently, various kinds of quantitative methods have been developed for measuring PCO. The purpose of this study was to compare the quantitative analysis of PCO between different types of IOL designs. Patients enrolled in the study had age-related cataract and underwent uneventful cataract surgery and implantation of either the AcrySof MA30BA (Alcon) or the Sensor AR40e (AMO), which are differently designed hydrophobic acrylic IOLs with a sharp-edged optic design. Postoperative examination was performed at 6 months. Retroillumination photographs of each eye were obtained, and the degree of PCO was assessed using the Evaluation of Posterior Capsule Opacification (EPCO) system. Grade 1 PCO was noted in both the MA30BA and the AR40e groups. There was no significant difference in the mean PCO score between the MA30BA and AR40e groups. Although the sharp-edged optic designs of both IOLs might similarly inhibit PCO at 6 months, a long-term follow-up period is needed to determine if any PCO differences occur between these 2 hydrophobic acrylic IOLs.

Posterior capsule opacification after combined cataract surgery and vitrectomy

To compare the degree of posterior capsule opacification (PCO) after combined cataract surgery and vitrectomy and after cataract surgery alone in age-matched control patients and in patients with and without diabetes mellitus (DM). Sugita Eye Hospital, Nagoya, Japan. In a prospective study, patients were divided into 2 groups: those having cataract surgery alone (cataract group) and those having combined cataract and vitrectomy surgery (combined group). The 2 groups were further divided into patients without DM (non-DM subgroup) and patients with DM (DM subgroup). The PCO rates were determined 3, 6, and 12 months after surgery using the POCO system. In the cataract group, the non-DM subgroup and the DM subgroup each comprised 42 eyes of 42 patients. In the combined group, the non-DM subgroup comprised 26 eyes of 26 patients and the DM subgroup, 23 eyes of 23 patients. In the cataract group, the PCO rate in the DM subgroup was significantly higher than in the non-DM subgroup at every postoperative examination (P<.05). In the non-DM subgroup, the PCO rate was significantly higher at every postoperative examination in patients having combined surgery than in patients having cataract surgery alone (P<.05). In the combined group, the PCO rate did not differ significantly between the non-DM subgroup and the DM subgroup. Even patients without DM must be carefully monitored for PCO development after combined surgery.

Influences of optic edge design on posterior capsule opacification and anterior capsule contraction

To investigate the influence of optic edge design on posterior capsule opacification (PCO) and anterior capsule contraction (ACC). A total of 43 eyes of 43 patients scheduled to undergo cataract surgery were included in this study. Patients received either a Sensor AR40 intraocular lens (IOL) or a Sensor AR40e IOL. The area of the anterior capsule opening (ACO) was determined by diaphanoscopy using the anterior eye segment analysis system EAS-1000 at 1 day, 1 week and 1, 3, 6 and 12 months postoperatively. Posterior capsule opacification was evaluated objectively in two ways, using either the EAS-1000 or POCOman. There was no significant difference between the two groups in either ACO area or percentage reduction of ACO area at any time-point after surgery. The difference in the degree of PCO 1 year after surgery was not significant when measured by either the EAS-1000 or POCOman. A sharp IOL edge is required to prevent PCO. Sharp-edged IOLs do not appear to be a risk factor for ACC.

Posterior capsule opacification after cataract surgery in patients with diabetes mellitus

To prospectively compare the degree of posterior capsule opacification (PCO) after cataract surgery in patients with and without diabetes mellitus. Sugita Eye Hospital, Nagoya, Japan. Forty-two eyes of 42 consecutive diabetes mellitus patients (DM group) and 42 eyes of 42 non-DM patients (control group) scheduled to have cataract surgery were enrolled. The PCO value was determined using the posterior capsule opacification (POCO) system 3, 6, and 12 months after surgery. Posterior capsule opacification values 3 months after surgery did not differ significantly between the 2 groups (P>.05). At 6 and 12 months, the PCO values of the DM group were significantly higher than those of the control group (P = .002 and P = .03, respectively). Diabetic patients had significantly more severe PCO after cataract surgery than nondiabetic patients.

Comparison of posterior capsule opacification between fellow eyes with two types of acrylic intraocular lens

To compare the degree of posterior capsule opacification (PCO) and visual function between fellow eyes that received two different types of hydrophobic acrylic intraocular lenses (IOLs). Forty-five patients underwent bilateral phacoemulsification and implantation of an Alcon AcrySof IOL (MA60AC) in one eye and an AMO Sensar IOL (AR40e) in the fellow eye. The PCO density value was measured using the Scheimpflug videophotography system at 1, 6, 12, and 24 months after surgery. The incidence of eyes that required a neodymium:YAG (Nd:YAG) laser capsulotomy, visual acuity, and contrast sensitivity with and without a glare source were also examined. The mean PCO value did not show a significant increase in either the AcrySof MA60AC or Sensar AR40e IOL groups, and was similar between the two groups throughout the 24-month follow-up period. The incidence of Nd:YAG laser capsulotomy was also the same between the groups. No significant difference was found in mean visual acuity between the two IOL groups during the follow-up, and there was no significant difference in photopic or mesopic contrast visual acuity with and without a glare source at 1 and 24 months after surgery. The degree of PCO in eyes with an AcrySof IOL are almost the same as that in eyes with a Sensar IOL, with the results that visual acuity and contrast sensitivity with and without glare are similar.

Posterior capsule opacification in myopic eyes

To determine whether posterior capsule opacification (PCO) is extensive in eyes with myopia or long axial length when an intraocular lens (IOL) of low-power, zero-power, or minus-power, is implanted. Hayashi Eye Hospital, Fukuoka, Japan. Ninety eyes of 90 patients scheduled for phacoemulsification surgery were recruited. These consisted of 30 eyes with high (> or =-8 diopters [D]) myopia, 30 eyes with moderate (<-8 D and > or =-3 D) myopia, and 30 eyes with low (<-3 D) myopia. All eyes had implantation of an acrylic IOL-low-power, zero-power, or minus-power-with a sharp optic edge (AcrySof MA60BM or MA60MA, Alcon Surgical). The PCO in these eyes was measured using a Scheimpflug videophotography system (EAS-1000, Nidek) 1, 3, 6, 12, 18, and 24 months after surgery. Visual acuity and the incidence of neodymium:YAG (Nd:YAG) laser posterior capsulotomy were also examined. No significant difference was observed in the mean PCO value or in the Nd:YAG capsulotomy rate between the high myopia, moderate myopia, or low myopia groups throughout the follow-up period. There was also no significant correlation between PCO value and the actual spherical power or axial length of the eye. Furthermore, although mean visual acuity tended to be worse in proportion to the degree of myopia, the difference was not statistically significant. When an acrylic IOL of low-power, zero-power, or minus-power with a sharp optic edge was implanted, high myopia and long axial length were not associated with the degree of PCO.

Prospective Intrapatient Comparison of 6.0-Millimeter Optic Single-Piece and 3-Piece Hydrophobic Acrylic Foldable Intraocular Lenses

To compare postoperative performance and stability of 6.0-mm optic single- and 3-piece acrylic foldable intraocular lenses (IOLs). Prospective, randomized, self-controlled trial. Eighty eyes of 40 patients with bilateral senile cataracts. Phacoemulsification and IOL implantation were performed. One eye of a patient was randomly assigned to the SA60AT single-piece IOL, and the contralateral eye was allocated to the MA60AC 3-piece IOL. Best-corrected visual acuity (BCVA), spherical equivalent, aqueous flare intensity, anterior chamber depth, amount of IOL decentration and tilt, area of anterior capsule opening, and degree of posterior capsule opacification (PCO) were measured 2 days, 1 week, and 1, 3, 6, and 12 months after surgery. Specular microscopy was performed at 12 months postoperatively. In the SA60AT group, the anterior chamber depth did not show significant changes after surgery (P>0.05; paired t test), and the refraction remained highly stable throughout the 1-year study period. The MA60AC group showed significant shallowing of the anterior chamber (P<0.05) and a myopic shift (P<0.05) up to 1 month after surgery. There were no significant differences between the 2 groups (P>0.05) in BCVA, aqueous flare intensity, the amount of IOL decentration, IOL tilt, area of anterior capsule opening, and degree of PCO throughout the 12-month follow-up period. Both the SA60AT single-piece and MA60AC 3-piece lenses showed a minimum amount of decentration, tilt, anterior capsule contraction, and PCO. Although the MA60AC showed significant forward shift and myopic refractive changes after surgery, the SA60AT displayed little axial movement associated with highly stable refraction after surgery. This feature of the SA60AT should facilitate earlier spectacle prescription and quicker visual/social rehabilitation of patients after cataract surgery.

Effect of TGF-β2 and Anti–TGF-β2 Antibody in a New In Vivo Rodent Model of Posterior Capsule Opacification

This study evaluated the effect of transforming growth factor (TGF)-beta2 and anti-TGF-beta2 antibody in a rodent model of posterior capsule opacification (PCO). An extracapsular lens extraction (ECLE) was performed in 72 Sprague-Dawley rats. At the end of the procedure, 10 microL TGF-beta2 (TGF-beta2-treated group), fetal calf serum (FCS)/phosphate-buffered saline (PBS; FCS/PBS-treated control group), a human monoclonal TGF-beta2 antibody (anti-TGF-beta2-treated group), or a null control IgG4 antibody (null antibody-treated control group) was injected into the capsule. Animals were killed 3 and 14 days postoperatively. Eyes were evaluated clinically prior to euthanatization, then enucleated and processed for light microscopy and immunohistochemistry afterward. PCO was evaluated clinically and histopathologically. Student's t-test and chi(2) were used to assess differences between groups. There were no statistically significant clinical or histopathological differences in degree of PCO between the TGF-beta2- and FCS/PBS-treated groups at 3 and 14 days after ECLE. Nor were there differences between the anti-TGF-beta2- and the null antibody-treated groups, with the exception of the histopathology score for capsule wrinkling 3 days after ECLE (P = 0.02). alpha-Smooth-muscle actin staining was observed in the lens capsular bag only in areas where there was close contact with the iris. No sustained effect of TGF-beta2 or anti-TGF-beta2 antibody on PCO was found in rodents at the dose and timing administered in this study. Iris cells may play a role in the process of epithelial mesenchymal transition linked to PCO.

Posterior Capsule Opacification in the Presence of an Intraocular Lens with a Sharp versus Rounded Optic Edge

To compare the degree of posterior capsule opacification (PCO) and visual function in eyes implanted with an acrylic intraocular lens (IOL) with a sharp posterior optic edge with that in eyes implanted with an IOL with a rounded optic edge. Randomized clinical trial. Seventy-five consecutive patients scheduled for bilateral phacoemulsification were assigned randomly to 1 of 2 groups. One group received an acrylic IOL with a sharp edge (Sensar AR40e, AMO, Santa Ana, CA) in the left eye and an acrylic IOL of the same optic material and loops but with a rounded-edge optic (Sensar AR40) in the right eye. The other group received the sharp-edged IOL in the right eye and the rounded-edge IOL in the left eye. Sixty-nine patients (92%) completed follow-up. All patients underwent implantation of a sharp-edged IOL in 1 eye and a rounded-edge IOL in the fellow eye. The PCO value of these patients was measured using the Scheimpflug videophotography system at 1, 3, 6, 12, 18, and 24 months after surgery. The incidence of eyes that required a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy was examined. Visual acuity and contrast sensitivity with and without a glare source also were evaluated. The mean PCO value in the sharp-edge IOL group was significantly less than that in the rounded-edge IOL group throughout the follow-up period. The incidence of Nd:YAG capsulotomy also was significantly less in the sharp-edge group than in the rounded-edge group (P = 0.0095). No significant difference was found in mean visual acuity during the 24 months of follow-up. However, contrast visual acuity with and without glare was significantly better in the sharp-edge group than in the rounded-edge group at 24 months after surgery. The degree of posterior capsule opacification in eyes with an acrylic IOL with a sharp posterior optic edge is significantly less than that in eyes with a rounded-edge IOL, and the sharp-edge optic led to better contrast sensitivity with and without glare.

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.

Correlation between posterior capsule opacification and visual function before and after Neodymium: YAG laser posterior capsulotomy

Purpose To investigate the correlation between visual acuity, contrast sensitivity, and contrast sensitivity with glare source (glare sensitivity), and the degree of posterior capsule opacification (PCO) before and after neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy. Design Prospective interventional case series. Methods Eighty-four patients (90 pseudophakic eyes) scheduled to undergo Nd:YAG laser capsulotomy were recruited. Visual acuity and contrast sensitivity with and without the presence of a circular glare source (using the contrast glare tester) were measured before and after Nd:YAG laser capsulotomy. The PCO density value was measured using a Scheimpflug videophotography system. The visual functions were statistically correlated with the PCO value. Results Before Nd:YAG laser capsulotomy, strong correlation existed between the PCO value and visual acuity ( r = 0.728). Contrast sensitivity and glare sensitivity were also weakly correlated with the PCO value, but the correlation coefficients were smaller than that of visual acuity. After Nd:YAG laser capsulotomy, mean visual acuity, contrast sensitivity, and glare sensitivity at all visual angles improved significantly ( P <.0001). After capsulotomy, no significant correlation was found between visual acuity, contrast sensitivity, or glare sensitivity and the PCO value. Conclusions Before Nd:YAG laser capsulotomy, visual functions correlated significantly with the degree of PCO. Specifically, visual acuity has a stronger association with PCO than does contrast sensitivity or glare sensitivity and therefore should be considered to reflect most accurately the degree of PCO. After capsulotomy, these visual functions improve markedly and no longer have a significant correlation with PCO.

Removal of reflections in the photographic assessment of PCO by fusion of digital retroillumination images.

Automated image-analysis systems for objective assessment of posterior capsule opacification (PCO) depend on good image quality. One major drawback is the existence of light-reflection artifacts (Purkinje spots) in retroillumination images of the posterior capsule. Therefore, a software algorithm was developed that removes these artifacts by fusion of two or more digital images from the same eye, photographed in slightly different directions of gaze. The image-fusion process comprises five steps: definition of a primary and a secondary image, automated segmentation of the region of interest and the Purkinje spots, manual selection of three pairs of corresponding points in both images, geometric registration and radiometric calibration of the regions to be inserted from the secondary image into the primary image. The program was tested with an image set of 30 eyes that had various degrees of PCO. A digital image acquisition system with a coaxial optical path was used to take retroillumination images from each eye in at least three different directions of gaze. In 28 cases all light-reflection artifacts within the capsulorrhexis rim could be removed entirely. In two cases, small parts of single Purkinje spots remained visible, because the reflections were located too closely in the primary and the secondary images. Fusion of digital retroillumination images provides high-quality, reflection-free PCO images. This allows objective PCO assessment systems to analyze 100% of the posterior capsule, leading to more accurate results.

Clinical Evaluation of Posterior Capsule Opacification in Eyes With Different Small-Incision Intraocular Lenses

To present a new method to quantify posterior capsular opacity with an anterior eye segment image analyzer (EAS 1000, NIDEK). This study was comprised of patients who underwent phacoemulsification intraocular lens (IOL) implantation. Three types of IOLS, acrylic, silicone, and polymethylmethacrylate (PMMA) were allocated to 30 eyes and clinically evaluated. Patients were observed for 3 years postoperatively using an anterior eye segment image analyzer (EAS1000). Opacity was determined by calculating the area of opacity from a retroillumination image. In the retroillumination mode of analysis, the measurement was limited to a 4-mm-diameter region of the pupillary zone to eliminate the influence of anterior capsular opacity. For color map analysis, the threshold level was expressed as the color tone of 0-255 CCT (computer compatible tape). The glare disability was measured to evaluate the three types of IOLs. The color map analysis revealed a time-related increase in the opacity level of patients receiving the PMMA IOL implant. Three years after surgery, the levels were significantly higher in the PMMA group (P < 0.01) compared to the acryl and silicone groups: acryl (17.5 +/- 3.8), silicone (18.0 +/- 6.2%), and PMMA 36.5 +/- 32.9%. Quantitative evaluation using an anterior eye segment image analyzer is effective for observing the degree of posterior capsule opacification. The color map analysis using an anterior eye segment image correlated with the visual function revealed that the time-related increase in the opacity level was significant during the third year in patients receiving PMMA IOL implantation.