Macular Degeneration: Girach A

Girach A, Lund-Andersen H. · Lilly Research Labs, Surrey, UK. · Int J Clin Pract. · Pubmed #17229183 No free full text.

Abstract: Diabetic retinopathy is the leading cause of blindness in working aged-adults in westernised countries. Diabetic macular oedema (DMO) is a manifestation of diabetic retinopathy and is the leading cause of the visual impairment that occurs with diabetic retinopathy. There are multiple ways of classifying DMO; however, none appear to be wholly satisfactory. DMO occurs more frequently in type 2 diabetes mellitus, and appears to be more prevalent as the duration of diabetes increases, and as the severity of diabetic retinopathy worsens. There are multiple risk factors in common with diabetic retinopathy, such as hyperglycaemia, hypertension and dyslipidaemia; however, specific factors such as the presence of renal disease appear to be more significantly associated with DMO. Whereas the gold standard for diagnosis of DMO is via clinical examination, there is considerable variability involved, and hence, this has led to the advent of more objective methods of quantifying the degree of retinal thickness, such as optical coherence tomography. Laser photocoagulation appears to be the only universally acceptable treatment of choice to date; however, this is a destructive therapy, and its side effects coupled with the suboptimal efficacy has led to the advent of potential new therapies which will undoubtedly compliment the existing approaches, in the future management of a patient with DMO.

Massin P, Girach A, Erginay A, Gaudric A. · Department of Ophthalmology, Lariboisiere Hospital, Paris, France. · Acta Ophthalmol Scand. · Pubmed #16879566 No free full text.

Abstract: Diabetic macular oedema is a major cause of visual loss in patients with diabetes. It usually results from the breakdown of the inner blood-retinal barrier. Early detection of retinal abnormalities is vital in preventing diabetic macular oedema and subsequent loss of vision, whilst assessment of retinal thickness is important for treatment and follow-up. Until recently, however, the methods available for detecting and evaluating diabetic macular oedema were slit-lamp biomicroscopy and stereoscopic photography, both of which are limited in detecting earlier retinal changes. Optical coherence tomography (OCT) is a new diagnostic imaging modality that provides high-resolution, cross-sectional images of the eye. It is proving to be an accurate tool for the early diagnosis, analysis and monitoring of retinopathy, with high repeatability and resolution. It allows not only the qualitative diagnosis of diabetic macular oedema, but also the quantitative assessment of oedema. This article reviews the future role of OCT in the management of patients with diabetic macular oedema.

Williams R, Airey M, Baxter H, Forrester J, Kennedy-Martin T, Girach A. · The Clinical School, University of Wales Swansea, Swansea, UK. · Eye. · Pubmed #15232600 No free full text.

Abstract: AIMS: To systematically review the literature on the prevalence and incidence of diabetic retinopathy (DR) and macular oedema (MO). METHODS: A search of the bibliographic databases (Medline, Embase, CINAHL) was conducted up to October 2001. Selected relevant studies were scrutinized and included in the review. RESULTS: A total of 359 studies were included. The studies were reported in nearly 100 different journals and in over 50 countries. The majority of the studies were US-based, with large studies such as the Wisconsin Epidemiologic Study of Diabetic Retinopathy dominating the literature. The studies were quite dated and highly heterogeneous in nature in terms of patient selection with variable inclusion criteria (age range, gender, diabetes duration and type, ethnicity, comorbidity, and DR status, assessment, and classification). CONCLUSIONS: There are inconsistencies between epidemiological studies, and differences in study methods may contribute to conflicting reports of prevalence and incidence of DR and MO in diabetic populations. As new therapies for DR and its associated complications emerge, the need to capture and monitor new epidemiological data becomes increasingly important to be able to assess the impact and effectiveness of these therapies. Robust, longitudinal capture of patient data is, therefore, essential to evaluate the impact of current practice on the epidemiology of diabetic eye complications.

Davis MD, Sheetz MJ, Aiello LP, Milton RC, Danis RP, Zhi X, Girach A, Jimenez MC, Vignati L, Anonymous00045. · Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, USA. · Invest Ophthalmol Vis Sci. · Pubmed #18708615 No free full text.

Abstract: PURPOSE: To compare relationships between severity and duration of diabetic macular edema (DME) and visual acuity (VA) observed in the PKC-DRS2 with those from the Early Treatment Diabetic Retinopathy Study (ETDRS) and to assess the effect of the orally administered PKC beta inhibitor ruboxistaurin (RBX) on these parameters. METHODS: In the PKC-DRS2, patients with moderately severe to very severe nonproliferative diabetic retinopathy (n = 685) were randomly assigned to 32 mg/d RBX or placebo and followed up for 36 months with ETDRS VA measurements and fundus photographs (FP) every 3 to 6 months. Mean VA was calculated across all FP visits for eyes in each level of the ETDRS DME severity scale at those visits. For eyes with baseline VA > or = 20/40, relationships between change in VA from baseline to last visit and duration of severe DME were analyzed with linear regression. RESULTS: Mean VA decreased by approximately 22 letters between the mildest and most severe levels of the DME scale in the PKC-DRS2, compared with 27 letters in the ETDRS. In the placebo group, the rate of decrease in VA over time associated with duration of severe DME was 0.67 letters per month (24 letters over 36 months, compared with 20 letters over 28-36 months in the ETDRS). This rate was 30% less in the RBX group (0.47 letter per month, P = 0.022). CONCLUSIONS: The VA decrease in the PKC-DRS2 associated with long-standing DME agrees well with estimates from the ETDRS. RBX appears to ameliorate this decrease, an effect that could be important clinically. (ClinicalTrials.gov number, NCT00604383.).

Sander B, Thornit DN, Colmorn L, Strøm C, Girach A, Hubbard LD, Lund-Andersen H, Larsen M. · Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Denmark. · Invest Ophthalmol Vis Sci. · Pubmed #17724176 links to  free full text

Abstract: PURPOSE: To study the progression of diabetic macular edema (DME) in relation to baseline retinal thickness, retinal vascular leakage, and retinal trunk vessel diameters. METHODS: In this single-center study, 45 patients were enrolled with 62 eligible eyes defined as having DME of a grade less than clinically significant macular edema (CSME). From the start, the patients were included in a multicenter study exploring the effect of ruboxistaurin versus placebo for 3.4 years. Subsequently, the patients were followed up for a mean of 5.7 years by optical coherence tomography, fundus photography, and vitreous fluorometry. Baseline values in eyes that progressed to photocoagulation treatment were compared with values from eyes that did not reach this endpoint. RESULTS: In the 22 eyes of 18 patients in which CSME was diagnosed and treated, mean retinal vascular leakage at baseline was 5.6 (95% CI 4.2-7.6) nm/s, whereas eyes that did not progress to photocoagulation had a significantly lower mean leakage at baseline of 3.4 (95% CI 2.7-4.3) nm/s. No significant difference was found for measures of baseline retinal thickness or summarized retinal trunk vessel diameters. Eyes that progressed to photocoagulation treatment (mean delay to treatment, 3.6 years) had significantly higher foveal thicknesses than did nonprogressing eyes, from 18 months after study initiation. CONCLUSIONS: Progression to photocoagulation treatment for CSME was associated with higher retinal vascular leakage at baseline, whereas baseline retinal vessel diameters and retinal thickness were comparable in progressing and nonprogressing eyes. Baseline leakage was the strongest predictor of progression from non-CSME to photocoagulation for CSME.

Anonymous00216, Aiello LP, Davis MD, Girach A, Kles KA, Milton RC, Sheetz MJ, Vignati L, Zhi XE. · Beetham Eye Institute, Joslin Diabetes Center, 1 Joslin Place, Boston, MA 02215, USA. · Ophthalmology. · Pubmed #16989901 No free full text.

Abstract: OBJECTIVE: To evaluate the effect of ruboxistaurin, an orally administered protein kinase C beta (PKC beta) isozyme-selective inhibitor, on vision loss in patients with diabetes. DESIGN: Thirty-six-month, randomized, double-masked, placebo-controlled, parallel, multicenter trial. PARTICIPANTS: Six hundred eighty-five patients randomized at 70 clinical sites. METHODS: Ophthalmologic examination was performed at screening and at each 3-month visit. Retinopathy status was assessed every 6 months with Early Treatment Diabetic Retinopathy Study (ETDRS) standard 7-field 30 degrees color stereoscopic fundus photography. Levels of diabetic retinopathy and diabetic macular edema were determined by 2 independent graders masked to site and treatment assignment, with additional independent adjudication as required. Eligible patients had a best-corrected visual acuity (VA) score of > or =45 letters, retinopathy level > or = 47A and < or = 53E, and no prior panretinal photocoagulation in at least one eye. MAIN OUTCOME MEASURE: Effect of oral ruboxistaurin (32 mg/day) on reduction of sustained moderate visual loss (> or =15-letter decrease in ETDRS VA score maintained > or = 6 months) in patients with moderately severe to very severe nonproliferative diabetic retinopathy. RESULTS: Sustained moderate visual loss occurred in 9.1% of placebo-treated patients versus 5.5% of ruboxistaurin-treated patients (40% risk reduction, P = 0.034). Mean VA was better in the ruboxistaurin-treated patients after 12 months. Baseline-to-end point visual improvement of > or =15 letters was more frequent (4.9% vs. 2.4%) and > or =15-letter worsening was less frequent (6.7% vs. 9.9%) in ruboxistaurin-treated patients relative to placebo (P = 0.005). When clinically significant macular edema was >100 microm from the center of the macula at baseline, ruboxistaurin treatment was associated with less frequent progression of edema to within 100 microm (68% vs. 50%, P = 0.003). Initial laser treatment for macular edema was 26% less frequent in eyes of ruboxistaurin-treated patients (P = 0.008). CONCLUSION: Oral ruboxistaurin treatment reduced vision loss, need for laser treatment, and macular edema progression, while increasing occurrence of visual improvement in patients with nonproliferative retinopathy.