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Intraocular Lens (intraocular + lens)
Selected AbstractsEffects of Light Exposure and Use of Intraocular Lens on Retinal Pigment Epithelial Cells In VitroPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2009Sheng Hui To investigate the effect of a blue light-filtering intraocular lens (IOL) and a UV-absorbing IOL on light-induced damage to retinal pigment epithelial (RPE) cells laden with the lipofuscin fluorophore N -retinylidene- N -retinylethanolamine (A2E), A2E-laden RPE cells were exposed to white light which was filtered by either a blue light-filtering IOL or a UV-absorbing IOL. After 30 min of illumination the cell viability and the level of reactive oxygen species (ROS), free glutathione (GSH), vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) were determined. In the absence of an IOL, the white light exposure decreased cell viability to 37.2% of the nonirradiated control. The UV-absorbing IOL tended to reduce light-induced cell death; however, the decrease was not significant. The blue light-filtering IOL significantly attenuated light-induced cell damage, increasing cell viability to 79.5% of the nonirradiated control. The presence of the blue light-filtering IOL significantly increased GSH and PEDF levels, and decreased ROS and VEGF levels. This study suggests that a blue light-filtering IOL may be more protective against A2E-induced light damage and inhibit more light-induced ROS and VEGF production than a conventional UV-absorbing IOL. [source] Intraocular lens as a drug delivery system for dexamethasoneACTA OPHTHALMOLOGICA, Issue 2 2010Maria Kugelberg Abstract. Purpose:, To evaluate the effect of an intraocular lens (IOL) coated with dexamethasone on postoperative inflammation after cataract surgery. Methods:, Clear lens extraction was performed bilaterally in eight 8-week-old rabbits. An uncoated silicone IOL (CeeOn; AMO, Santa Ana, CA, USA) was implanted in one randomly selected eye. In the other eye, the same silicone IOL model was implanted but was coated with dexamethasone. Aqueous humour was obtained preoperatively and on days 1, 3, 7, 14 and 28 postoperatively. Three inflammatory parameters were measured and compared between the eyes: prostaglandin E2 (PGE2), white blood cell (WBC) count and protein content. The animals were killed on day 28 postoperatively. Results:, PGE2 levels measured on days 1, 3 and 7 were significantly lower in eyes with a coated IOL compared to eyes with an uncoated IOL (p < 0.01). The WBC count was significantly lower in eyes with a coated IOL on days 1 (p < 0.01) and 3 (p < 0.05). There was significantly less protein in eyes with a coated IOL on days 1 and 3 (p < 0.01). Conclusion:, Coating a silicone IOL with dexamethasone significantly reduced postoperative inflammation after clear lens extraction in rabbits. [source] Determination of pseudophakic accommodation with translation lenses using Purkinje image analysisOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 2 2005Achim Langenbucher Abstract Purpose:, To determine pseudophakic accommodation of an accommodating posterior chamber intraocular lens (translation lens) using Purkinje image analysis and linear matrix methods in the paraxial space. Methods:, A 2 × 2 system matrix was defined for each Purkinje image I to IV using refraction, translation and mirror matrices. Image size (m) and axial image position (z) was determined as an example for an off-axis object (a 0.2 m off-axis object located 0.5 m in front of the cornea.). First, our method was applied to the phakic relaxed (emmetropic) and accommodated (6.96 D) Le Grand eye. Secondly, for demonstration of the applicability of the calculation scheme to the pseudophakic eye, we provide a clinical example where we determine the accommodation amplitude of the translation lens (1 CU, HumanOptics, Erlangen, Germany) from photographed Purkinje images in the relaxed and accommodated state. From the biometric data: axial length 23.7 mm, corneal power 43.5, corneal thickness 550 microns, implanted intraocular lens (IOL) with a refractive power of 20.5 D (shape equi-biconvex, refractive index 1.46), and refractive indices of the cornea, aqueous and vitreous from the Le Grand model eye, we calculated the refractive state and the sizes of Purkinje images I and III initiated from two off-axis light sources. Results:, For the Le Grand model eye, Purkinje image II (z/m = 3.5850 mm/0.0064) is slightly smaller than and directly in front of image I (z/m = 3.8698 mm/0.0077). Purkinje image III (z/m = 10.6097 mm/0.0151) is nearly double the size of image I and during accommodation it moves from the vitreous into the crystalline lens. Purkinje IV (z/m = 4.3244 mm/,0.0059) is inverted, three quarters the size of image I, lies in the crystalline lens and moves slightly towards the retina. For the pseudophakic eye, pseudophakic accommodation of 1.10 D was calculated from the proportion of distances between both Purkinje images I and III in the relaxed (3.04) and accommodated (2.75) state, which is in contrast to the total subjective accommodation of 2.875 D evaluated with an accommodometer. Conclusions:, We present a straightforward mathematical strategy for calculation of the Purkinje images I,IV. Results of our model calculation resemble the values provided by Le Grand. In addition, this approach yields a simple en bloc scheme for determination of pseudophakic accommodation in pseudophakic eyes with accommodative lenses (translation lenses) using Purkinje image photography. [source] Economic costs of cataract surgery using a rigid and a foldable intraocular lens,OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2001Asfa J. Afsar Summary Optimal delivery of healthcare requires consideration of various costs. A foldable intraocular lens (IOL) is more expensive than an equivalent rigid IOL. However, surgical and post-operative costs may make a foldable IOL economically preferable. We compared the economic costs of cataract surgery plus implantation of a foldable IOL with implantation of a rigid IOL. Prospective audit of the clinical records of 82 pseudophakes; 39 implanted with a rigid IOL and 43 implanted with a foldable IOL by one surgeon. Average follow-up periods were 25±7 months and 23±5 months respectively. There was no difference between the two groups for the follow-up period (P=0.55), number of post-operative complications (P=0.25) or cost of post-operative visits (P=0.83). The cost of single-use theatre equipment was greater for the rigid-IOL group (P=0.0001). The total identified cost per patient was greater for the foldable-IOL group (P=0.0001). Despite possible technical advantages, implantation of the foldable IOL did not provide an economic benefit, either in the initial cost or in the costs of post-operative care. Over the 2-year period, implanting with the rigid IOL cost, on average, £57 less per patient. Despite this economic difference, a cost-benefit analysis is required, since other factors may be more important. [source] Effects of Light Exposure and Use of Intraocular Lens on Retinal Pigment Epithelial Cells In VitroPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2009Sheng Hui To investigate the effect of a blue light-filtering intraocular lens (IOL) and a UV-absorbing IOL on light-induced damage to retinal pigment epithelial (RPE) cells laden with the lipofuscin fluorophore N -retinylidene- N -retinylethanolamine (A2E), A2E-laden RPE cells were exposed to white light which was filtered by either a blue light-filtering IOL or a UV-absorbing IOL. After 30 min of illumination the cell viability and the level of reactive oxygen species (ROS), free glutathione (GSH), vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) were determined. In the absence of an IOL, the white light exposure decreased cell viability to 37.2% of the nonirradiated control. The UV-absorbing IOL tended to reduce light-induced cell death; however, the decrease was not significant. The blue light-filtering IOL significantly attenuated light-induced cell damage, increasing cell viability to 79.5% of the nonirradiated control. The presence of the blue light-filtering IOL significantly increased GSH and PEDF levels, and decreased ROS and VEGF levels. This study suggests that a blue light-filtering IOL may be more protective against A2E-induced light damage and inhibit more light-induced ROS and VEGF production than a conventional UV-absorbing IOL. [source] Intraocular lens as a drug delivery system for dexamethasoneACTA OPHTHALMOLOGICA, Issue 2 2010Maria Kugelberg Abstract. Purpose:, To evaluate the effect of an intraocular lens (IOL) coated with dexamethasone on postoperative inflammation after cataract surgery. Methods:, Clear lens extraction was performed bilaterally in eight 8-week-old rabbits. An uncoated silicone IOL (CeeOn; AMO, Santa Ana, CA, USA) was implanted in one randomly selected eye. In the other eye, the same silicone IOL model was implanted but was coated with dexamethasone. Aqueous humour was obtained preoperatively and on days 1, 3, 7, 14 and 28 postoperatively. Three inflammatory parameters were measured and compared between the eyes: prostaglandin E2 (PGE2), white blood cell (WBC) count and protein content. The animals were killed on day 28 postoperatively. Results:, PGE2 levels measured on days 1, 3 and 7 were significantly lower in eyes with a coated IOL compared to eyes with an uncoated IOL (p < 0.01). The WBC count was significantly lower in eyes with a coated IOL on days 1 (p < 0.01) and 3 (p < 0.05). There was significantly less protein in eyes with a coated IOL on days 1 and 3 (p < 0.01). Conclusion:, Coating a silicone IOL with dexamethasone significantly reduced postoperative inflammation after clear lens extraction in rabbits. [source] Longterm results after phacovitrectomy and foldable intraocular lens implantationACTA OPHTHALMOLOGICA, Issue 8 2009Wensheng Li Abstract. Purpose:, This study aimed to evaluate the longterm results of phacovitrectomy and foldable intraocular lens (IOL) implantation in eyes with significant cataract and co-existing vitreoretinal diseases. Methods:, We carried out a retrospective study of 186 eyes of 149 patients with various vitreoretinal abnormalities and visually significant cataracts. Vitreoretinal surgery was combined with phacoemulsification and foldable IOL implantation. Main outcome measures were visual acuity (VA), preoperative data, and intraoperative and postoperative complications. Results:, The most common indications for surgery were non-diabetic vitreous haemorrhage and proliferative diabetic retinopathy. Preoperative vision ranged from 0.6 to light perception; postoperative vision ranged from 1.2 to no light perception. Postoperatively, in 162 eyes (87.1%) VA improved by , 3 lines on the decimal chart. In 14 eyes (7.5%), vision remained within 3 lines of preoperative levels and in 10 eyes (5.3%), vision had decreased by the last follow-up. Postoperative complications included elevated intraocular pressure and posterior capsule opacification, corneal edema, macular edema, fibrinous reaction, vitreous hemorrhage, corneal epithelial defects, anterior chamber hyphema, choroidal detachment, persistent macular hole, posterior synechiae, recurrent retinal detachment, rubeosis iridis, neovascular glaucoma. Conclusions:, Combined vitreoretinal surgery and phacoemulsification with foldable IOL implantation is safe and effective in treating vitreoretinal abnormalities co-existing with cataract. Based on extensive experience with the combined procedure, we suggest that combined surgery is recommended in selected patients with simultaneous vitreoretinal pathological changes and cataract. [source] Early changes in clear cornea incision after phacoemulsification: an anterior segment optical coherence tomography studyACTA OPHTHALMOLOGICA, Issue 7 2009Yuanling Xia Abstract. Purpose:, We aimed to investigate the ultrastructures of clear corneal incisions 24 hours after phacoemulsification using anterior segment optical coherence tomography (AS-OCT). Methods:, Sixty eyes of 60 patients scheduled for cataract surgery were randomly selected. All eyes underwent the same phacoemulsification procedure carried out by one experienced surgeon. Two-plane temporal clear corneal tunnel incisions were performed. The same types of intraocular lens and implant system were used in all patients. Images of the ultrastructures of the corneal incisions were taken using AS-OCT before and 1 day after surgery. Results:, Corneal thickness increased at the incision site after surgery in all eyes (p < 0.001). Epithelial bulla in the incision region was seen in two eyes (3%). Gaping at the internal aspect of the corneal wound was seen in 42 eyes (70%). Eyes with gaping had thicker localized cornea (p = 0.002). Descemet's membrane detachment was seen in 49 eyes (82%); this seemed to be associated with lower preoperative intraocular pressure (p = 0.01). Conclusions:, Anterior segment OCT provides sensitive and detailed measurements of the ultrastructures in clear corneal incision. [source] Prophylaxis of posttraumatic endophthalmitisACTA OPHTHALMOLOGICA, Issue 2009A ABU EL ASRAR Infectious endophthalmitis is a devastating complication of open globe injuries. The incidence of culture-positive endophthalmitis after open globe injuries varies between 0.5% and 17%. Several reports have demonstrated that delayed primary repair, dirty wound, breach of lens capsule, retained intraocular foreign body (IOFB), grade 4 injury (presenting visual acuity of worse than 5/200 to light perception), placement of primary intraocular lens, and rural setting are associated with an increased risk of posttraumatic endophthalmitis. Posttraumatic endophthalmitis is associated with its own microbiologic spectrum which is distinct from other subgroups of exogenous endophthalmitis. Posttraumatic endophthalmitis still carries a poor prognosis. Reasons for guarded prognosis include polymicrobial infection and the virulence of the infecting microorganisms. In addition, concomitant injuries may directly result in ocular damage that limits ultimate visual recovery. Because of the substantial incidence of endophthalmitis after open globe injuries, careful consideration should be given to the use of prophylactic antimicrobial therapy. The purpose of prophylaxis is to provide effective antibiotic levels as rapidly as possible against a broad range of organisms. Good coverage for most organisms is obtained with intravenous vancomycin coupled with a third generation cephalosporin, such as ceftazidime, which can penetrate the vitreous cavity in effective levels in inflamed aphakic experimental eyes. Recently, the use of prophylactic intravitreal antibiotic administration in high-risk cases was recommended. [source] Anterior chamber parameters measured by the Pentacam CES after uneventful phacoemulsification in normotensive eyesACTA OPHTHALMOLOGICA, Issue 5 2009Özlenen Ö. Uçakhan Abstract. Purpose:, We set out to quantify changes in the anterior chamber volume (ACV), anterior chamber depth (ACD) and anterior chamber angle (ACA) measurements obtained by the Pentacam rotating Scheimpflug camera following uneventful phacoemulsification surgery in normotensive eyes with open iridocorneal angles. Methods:, We enrolled 44 eyes of 44 consecutive patients undergoing cataract extraction in this prospective study. Patients with a history of glaucoma, angle-closure glaucoma or any other concurrent ocular disease were excluded. A detailed eye examination including intraocular pressure (IOP) measurement was performed and ACV, ACD and inferior, superior, temporal and nasal ACA measurements were obtained in each patient eye using the Pentacam Comprehensive Eye Scanner (Pentacam CES) before and 3 months after phacoemulsification and intraocular lens (IOL) implantation with temporal clear corneal incision. Data were compared using paired t -test and one-way anova. Results:, Mean preoperative ACV, ACD, ACA and IOP measurements were 164.7 ± 49.8 mm3, 3.0 ± 0.8 mm, 35.7 ± 10.2 ° and 15.8 ± 3.7 mmHg, respectively. Three months postoperatively, mean ACV, ACD, ACA and IOP measurements were 200.9 ± 33.3 mm3, 3.9 ± 0.9 mm, 41.5 ± 6.5 ° and 13.2 ± 3.9 mmHg, respectively. Postoperative mean ACV, ACD and ACA values in all four quadrants were significantly increased (p < 0.0001, p < 0.0001, p < 0.0001, respectively), whereas IOP was significantly reduced (p < 0.0001). Conclusions:, The Pentacam CES allowed very easy, fast, automatic and non-contact quantification of the anterior chamber parameters pre- and postoperatively in all patient eyes. Measurements obtained confirm that in normotensive eyes with open iridocorneal angles, the ACV and ACD increase and the ACA widens in all quadrants 3 months after uneventful phacoemulsification and IOL implantation. These changes are accompanied by a significant fall in IOP in the short term. [source] Preoperative topical cyclopentolate can be omitted when using intracameral lidocaine in phacoemulsification surgeryACTA OPHTHALMOLOGICA, Issue 3 2009Björn Lundberg Abstract. Purpose:, To evaluate the mydriatic effect of topical cyclopentolate 1% when combined with topical phenylephrine 10% and intracameral lidocaine 1% in phacoemulsification cataract surgery. Methods:, We performed a prospective, double-masked, randomized trial including 20 patients with age-related cataract, who were scheduled for unilateral phacoemulsification and intraocular lens (IOL) implantation. Patients were given either two drops of phenylephrine 10% at 30 mins and 15 mins prior to surgery (group 1), or two drops each of cyclopentolate 1% and phenylephrine 10% at the same time points (group 2). All patients were also given lidocaine 1% intracamerally at the beginning of the procedure. Intraoperative pupil sizes were assessed from video-recordings. Results:, Initially, pupil sizes were significantly smaller in group 1 (4.8 ± 1.2 mm versus 6.5 ± 1.4 mm; p = 0.0098), but the lidocaine injection increased the pupil sizes in group 1 significantly, so that pupil sizes in both groups were equalized throughout the surgical procedure. Conclusions:, Preoperative topical cyclopentolate does not enhance mydriasis in phacoemulsification surgery when using intracameral lidocaine and can be omitted when intracameral lidocaine is used. [source] Phakic pattern of exfoliation material on a posterior chamber intraocular lensACTA OPHTHALMOLOGICA, Issue 1 2009Ibrahim Hepsen No abstract is available for this article. [source] Long-term results of cataract surgery with implantation of a mechanically, reversibly adjustable intraocular lens: *Acri.Tec AR-1 PC/IOLACTA OPHTHALMOLOGICA, Issue 2008CE JAHN Purpose To investigate long-term safety and function of a mechanically, reversibly adjustable intraocular lens in human eyes Methods Clinical long-term monitoring of the initial 38 eyes of 38 patients with senile cataract after implantation of the *Acri.Tec AR-1 PC/IOL including a control group. Results Median follow-up was 25 (range 6 to 52 months). Throughout the entire period of observation all eyes were behaving clinically in the same way as if implanted with a conventionel PC/IOL. 2 eyes were adjusted surgically 2 weeks after implantation. 19/38 eyes underwent Nd:YAG laser capsulotomy after a median period of 12 (range 6 to 43) months after implantation. Median change of spherical equivalent between 1 month and the last visit was 0 (range , 0.5 to + 0.5) diopters. At the last visit median best visual acuity was 0.7 (range 0.2 to 1.0) for eyes with the *Acri.Tec AR-1 PC/IOL and 0.8( range 0.3 to 1.0) for the control group. Both eyes having undergone adjustment surgery had visual acuity of 0.8 rsp 1.0 with stable refractions 45 rsp. 42 months after adjustment surgery. Conclusion The *Acri.Tec AR-1 PC/IOL implanted into the capsular bag of adult human eyes is a safe PC/IOL. Refraction is predictably adjustable after implantation. It remains stable before and after Nd:YAG laser capsulotomy or after surgical adjustment of the refraction. This type of IOL may prove helpful especially in pediatric cataract surgery to avoid the development of amblyopia and in adults when precise refractive outcome is important either because of individual preference of the patient for a preferred refraction or because of intendend monovision to reduce spectacle dependence to a minimum. Commercial interest [source] High Order Aberrations of the eye implanted the Verisyse® iris-claw intraocular lensACTA OPHTHALMOLOGICA, Issue 2007JJ GICQUEL Purpose: To investigate the influence of the secondary implantation site of the Verisyse® iris-claw intraocular lens (IOL) on high order aberrations (HOAs) using wavefront analysis in aphakic patients. Methods: Twenty aphakic patients (20 eyes) who had complicated phacoemulsification, leaving no capsular support, but good iris support and clear unwounded cornea implantated with the aphakic Verisyse®(AMO) intraocular lens site either implanted retropupilarely or over the iris. Wavefront aberrations were measured using the IRX3 Hartmann-Shack aberrometer at 4 mm pupil aperture diameter. Results: Nine patients were implanted in the anterior chamber versus 11 who had the IOL clipped behind the iris. Best corrected visual acuity was significantly higher and HOAs were significantly lower in the retropupilarely implanted group. Conclusions: In addition to being atraumatic, the Verisyse® intraocular lens implanted behind the iris may restore vision in the absence of capsular support in a more physiological way than when fixated over the iris. [source] Influences of optic edge design on posterior capsule opacification and anterior capsule contractionACTA OPHTHALMOLOGICA, Issue 1 2007Kazunori Miyata Abstract. Purpose:, To investigate the influence of optic edge design on posterior capsule opacification (PCO) and anterior capsule contraction (ACC). Methods:, 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. Results:, 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. Conclusions:, A sharp IOL edge is required to prevent PCO. Sharp-edged IOLs do not appear to be a risk factor for ACC. [source] YAG curios #1: repeat Nd:YAG laser posterior capsulotomyACTA OPHTHALMOLOGICA, Issue 2 2005Hari Jayaram Abstract. A descriptive case series of five patients identified either opportunistically or from a retrospective review of the laser register is presented. All underwent cataract surgery between 1995 and 1999 and required initial Nd:YAG laser posterior capsulotomy 15,30 months after surgery. They subsequently developed reclosure of the capsulotomy, necessitating repeat laser capsulotomy 11,82 months later. One patient, who received a hydrogel intraocular lens, required a third capsulotomy after a further 12 months. The rate of repeat Nd:YAG laser capsulotomy in our unit was 0.31%. [source] Late opacification of a hydrophilic acrylic intraocular lensACTA OPHTHALMOLOGICA, Issue 1 2003Orhan Baykal First page of article [source] Surface modification of silicone intraocular lens by 2-methacryloyloxyethyl phosphoryl-choline binding to reduce Staphylococcus epidermidis adherenceCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2007Xiao-Dan Huang MD Abstract Purpose:, To analyse the in vitro adherence of Staphylococcus epidermidis to the 2-methacryloyl oxyethyl phosphorylcholine (MPC)-modified silicone intraocular lens (IOL). Methods:, The test IOLs were modified by using an air plasma treatment to bind MPC to the surface. The control IOLs were not modified. Chemical changes on the IOL surface were analysed by X-ray photoelectron spectroscopy (XPS) to confirm the covalent binding of MPC. IOL hydrophilicity was determined by measuring the water contact angle. Two different techniques, direct counting of viable adherent bacteria released by sonication, and scanning electron microscopy (SEM), were used to observe and compare the adherence of S. epidermidis to the IOLs after 1- and 18-h incubation. Results:, XPS analysis confirmed that the test IOLs were surface-modified with MPC. The hydrophilicity of the IOLs was improved by surface modification, and the MPC-modified IOLs exhibited significantly reduced adhesion of S. epidermidis (P = 0.002) after an incubation period of 1 h. The SEM results showed that the MPC modification also suppressed the accumulation of bacteria and biofilm production after 18 h incubation. Conclusions:, MPC-modified hydrophilic silicone IOLs reduce bacterial adherence and colonization, and thus may help reduce the incidence of postoperative endophthalmitis. [source] Aberration and contrast sensitivity comparison of aspherical and monofocal and multifocal intraocular lens eyesCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2007Mingbing Zeng PhD MD Abstract Background:, Higher-order aberrations and contrast sensitivity were evaluated in patients who underwent phacoemulsification cataract extraction followed by implantation of aspherical, monofocal or multifocal intraocular lens (IOL) replacements. Methods:, In this comparative trial, 124 patients with an average age of 66.8 ± 5.2 years and their 124 eyes were randomly divided into three surgical implantation groups to receive one of three types of IOLs in replacement of cataract lenses. The patients of group 1 were given an aspherical IOL Z9001 (AMO, Santa Ana, CA, USA) replacement, and group 2 was implanted a monofocal IOL SA60AT (Alcon, Fort Worth, TX, USA) and group 3 the multifocal IOL SA40N (AMO). Post-surgical best-corrected visual acuity, corneal aberrations, total ocular aberrations, pupil diameters, capsulorhexsis sizes and contrast sensitivity were measured and compared. Results:, There was no statistical difference for mean best-corrected visual acuity, pupil diameter, curvilinear capsulorhexis size and corneal aberration among the three groups. For the spherical aberration, fourth-order higher-order aberration and total ocular higher-order aberration, the SA40N group was higher than the SA60AT group and the SA60AT group was higher than the Z9001 group, and the differences between the three groups were statistically significant for these measurements. Contrast sensitivity was higher for the Z9001 group than the SA60AT group and the SA60AT group was higher than the SA40N group, and the difference was statistically significant in all the spatial frequencies of 3, 6, 12 and 18. Conclusions:, Although the multifocal IOL can provide near vision, it can increase higher-order aberration and negatively influence contrast sensitivity. However, the aspherical IOL can reduce aberration and improve contrast sensitivity as compared with the monofocal IOL. [source] Paediatric pseudophakia: analysis of intraocular lens power and myopic shiftCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2007William F Astle MD Abstract Background: At the Alberta Children's Hospital, the authors have been performing paediatric cataract extraction with intraocular lens (IOL) implant for over 10 years. The authors examined the amount of myopic shift that occurs in various age groups and cataract types, in order to evaluate the success of predicting the appropriate power of IOL to implant. Methods: This study is a retrospective review children undergoing small incision posterior chamber foldable IOL implantation between age 1 month and 18 years, from 1995 to 2005. 163 eyes of 126 patients underwent surgery. All patients were followed for a minimum of 6 months postoperatively. The children were divided into four groups at time of surgery: Group A: 1,24 months, Group B: 25,48 months, Group C: 49,84 months, Group D: 85 months,18 years. Results: The mean target refraction for the groups were: Group A: +6.37 D, Group B: +4.66 D, Group C: +1.95 D, and Group D: +0.97 D. Children under 4 years experienced the most myopic shift and the largest mean rate of refractive change per year. Mean change Group A: ,5.43 D, Group B: ,4.16 D, Group C: ,1.58 D, Group D: ,0.71 D. Eighty-nine per cent of patients with unilateral cataracts had a postoperative refraction within 3.00 D of the fellow eye at last follow-up visit (mean = 3.16 years). Conclusions: The rate of myopic shift is high in children under age 4 years at time of surgery, shifting as much as ,12.00 D. The mean postoperative target refraction should probably be increased from previous literature recommendations. The patient's age at time of cataract surgery and the refractive power of fellow eye are all factors to consider when deciding what power IOL to surgically implant in a paediatric patient. [source] | ||||||||||