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Title: Posterior capsular opacification : incidence and factors influencing the rate of Nd:YAG capsulotomy in diabetic and uveitic patients and after multifocal intraocular lens implantation
Author: Elgohary, Mostafa A.
ISNI:       0000 0001 3442 8062
Awarding Body: University of London
Current Institution: University College London (University of London)
Date of Award: 2005
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This thesis examined the incidence and factors affecting the rate of posterior capsular opacification (PCO), the most common complication of cataract surgery, in diabetic and uveitic patients and in patients with multifocal intraocular lenses (IOLs). These patients arc particularly sensitive to PCO development because of the risks associated with Nd:YAG capsulotomy in the former two groups and the potential effect on visual function in the latter group. PCO rate was estimated both retrospectively, using Nd:YAG capsulotomy as a surrogate measure of clinically significant PCO, as well as prospectively using clinical and imaging methods. Diabetic patients were found to have a lower incidence and risk of Nd:YAG capsulotomy than non-diabetic patients within 4 years after surgery. Young age, postoperative inflammation, pars plana vitrectomy and, in comparison to 3-piece silicone IOL, polymethylmethacrylate (PMMA) and plate-haptie silicone IOLs were associated with increased risk of Nd:YAG capsulotomy. In subgroup analysis, male gender was found to be a risk factor in the non-diabetic group and the duration and type of diabetes and diabetic retinopathy grade were not risk factors. In a prospective randomised trial, hydrophobic acrylic IOLs, while associated with a higher flare value within the early postoperative period, had a significantly lower rate of PCO development than plate-haptic silicone IOLs after 6 months and 1 year in diabetic patients. Optical coherence tomography revealed the development of a characteristic mid-peripheral apposition between the optic and the posterior capsule with hydrophobic acrylic IOLs both early and late after surgery, and the lack thereof with plate-haptic silicone IOLs, which is consistent with and explains the difference in PCO rate between the two IOLs. In uveitic patients, the incidence of Nd:YAG capsulotomy was higher within the first two years after surgery than in non-uveitic patients, although the presence of uveitis was not an independent risk factor for an increased rate of Nd:YAG capsulotomy. The use of preoperative systemic steroids reduced the risk of Nd:YAG capsulotomy and, in comparison to PMMA IOLs, silicone IOLs reduced the risk of Nd:YAG capsulotomy while hydrophilic acrylic IOLs and young age increased it. In patients with multifocal IOLs, within 4 years of follow-up the incidence of PCO and Nd:YAG capsulotomy were similar to those reported with monofocal implants and young age was a risk factor for the development of PCO. Patients with multifocal IOLs present for Nd:YAG capsulotomy with earlier loss of high and low-contrast acuity, which could increase the rate of Nd:YAG capsulotomy in these patients.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (M.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available