Phacoemulsificatıon in eyes with cataract and high myopia

ABSTRACTPurpose:To evaluate the outcomes and complications following phacoemulsification surgery in eyes with cataract and high myopia.Methods:We retrospectively evaluated the data of 43 eyes of 28 consecutive patients (12 males, 16 females) with cataract and high myopia who had undergone phacoemulsification and intraocular lens (IOL) implantation. The mean [± standard deviation (range)] age of the patients was 59.20 ± 11.08 (39-77) years.Results:The frequency of nuclear cataract was significantly higher than that of other cataract types (P=0.003). The mean axial length was 28.97 ± 1.99 (26-33) mm and the mean IOL power was 5.09 ± 4.78 (-3.0 to +14.0) diopters (D). The mean preoperative spherical equivalent (SE) was -16.48 ± 5.23 (-8.00 to -25.00) D and the mean postoperative SE was -1.46 ± 0.93 (0.00 to -3.00) D (P=0.00). The mean preoperative best-corrected visual acuity (BCVA) was 0.91 ± 0.37 (0.30 to -1.50) logMAR and the mean postoperative BCVA was 0.29 ± 0.25 (0.00-1.00) logMAR (P=0.00). Twenty-two eyes (51.2%) achieved the target postoperative refraction (±1.0 D). The eyes were divided into 3 groups according to the axial length. The mean biometric error was significantly higher in the group with the greatest axial length than in the other groups (P=0.007). Preoperative argon laser photocoagulation was performed in 7 eyes (16%) on account of retinal tears, retinal holes, or lattice degeneration. Postoperatively, retinal tears developed in 2 eyes (4%) and were treated with photocoagulation. One eye (2%) developed retinal detachment postoperatively, with the patient consequently referred for retinal surgery. Postoperatively, posterior capsule opacities developed in 11 eyes (25%), with all cases treated by laser capsulotomy.Conclusions:Good postoperative outcomes following phacoemulsification surgery were observed in patients with cataract and high myopia. However, clinicians should be aware of the risk of postoperative retinal tears and rhegmatogenous retinal detachment. Preoperative prophylactic argon laser photocoagulation treatment should be considered where necessary

The influence of size and shape of Nd:YAG capsulotomy on visual acuity and refraction

ABSTRACTPurpose:To evaluate the influence of size and shape of neodymium:yttrium aluminum- Garnet (Nd:YAG) laser capsulotomy on visual acuity and refraction.Methods:We retrospectively evaluated 85 eyes of 67 patients treated with Nd:YAG laser posterior capsulotomy for posterior capsule opacification (PCO). The mean age of included patients was 57.57 ± 9.26 (mean ± standard deviation, 38-75 years). The mean interval between surgery and Nd:YAG laser capsulotomy was 26.09 ± 7.08 (10-38) months. Patients were divided into four groups according to the shape and size of capsulotomy. Groups comprised patients with cruciate shape capsulotomies with openings of less than or equal to 3.5 mm (Group 1) or greater (Group 2) and patients with circular shape capsulotomies with openings of less than or equal to 3.5 mm (Group 3) or greater (Group 4).Results:The mean number and energy of laser firings were significantly higher in Group 4 (p=0.00), and significantly lower in Group 1 (p=0.00), compared with that in other groups. Pre-procedural and post-procedural mean spherical equivalent (SE) values were significantly higher in Group 1 (p=0.026 and p=0.011, respectively). No statistical difference in best-corrected visual acuities (BCVA) or intraocular pressures (IOP) were observed between groups before (p=0.44 and p=0.452, respectively) or after capsulotomy (p=0.108 and p=0.125, respectively). A significantly higher number of patients in Group 4 (p=0.001), and a significantly lower number of patients in Group 1 (p=0.001), reported floating bodies compared with that in other groups. No significant changes in SE or intraocular pressure were observed after capsulotomy in any group (p=0.074 and p=0.856, respectively). Best-corrected visual acuity was significantly improved following capsulotomy in all groups (p<0.01).Conclusion:Cruciate shape capsulotomy with an opening of 3.5 mm or less provides the greatest improvement in visual function with minimal complications

Visual outcomes of multifocal intraocular lens implantation in patients with cataract and high hyperopia and patient selection

Letter to the Edto

Statistical Scenarios for Demand Forecast of a High Voltage Feeder: A Comparative Study

The electricity demand forecasting has gained remarkable concern in energy market operation and planning with the emergence of deregulation in the power industry. Power system operators benefit from accurate demand forecasts by supporting investment decisions more objectively. As a crucial requirement, this paper focuses on hourly demand forecasts of a high voltage feeder. Moving average (MA), weighted moving average (WMA), autoregressive moving average (ARMA) and autoregressive integrated moving average (ARIMA) models have been used for creating statistical demand scenarios at 1-h, 2-h, 3-h and 4-h intervals. Many constructive comparisons have been conducted among MA, WMA, ARMA and ARIMA models comprehensively. Besides, the best statistical model employed in each hourly demand scenario provides the robust improvement percentage with respect to the persistence model

Statistical scenarios for demand forecast of a high voltage feeder: A comparative study

The electricity demand forecasting has gained remarkable concern in energy market operation and planning with the emergence of deregulation in the power industry. Power system operators benefit from accurate demand forecasts by supporting investment decisions more objectively. As a crucial requirement, this paper focuses on hourly demand forecasts of a high voltage feeder. Moving average (MA), weighted moving average (WMA), autoregressive moving average (ARMA) and autoregressive integrated moving average (ARIMA) models have been used for creating statistical demand scenarios at 1-h, 2-h, 3-h and 4-h intervals. Many constructive comparisons have been conducted among MA, WMA, ARMA and ARIMA models comprehensively. Besides, the best statistical model employed in each hourly demand scenario provides the robust improvement percentage with respect to the persistence model