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Purpose Photodynamic therapy (PDT) has been widely used in the treatment of age-related macular degeneration (AMD). The complement cascade has an important role in the tissue reactions occurring after PDT. The Y402H polymorphism of the complement factor H (CFH) gene has been identified as a risk factor for AMD. Since CFH is central in the regulation of the complement system the authors wanted to analyze whether the CFH Y402H polymorphism modifies the PDT outcome in AMD. Methods A total of 88 patients having been treated with PDT and without further scheduled PDT sessions were analyzed. Depending on the situation at their final PDT session the patients were classified retrospectively as PDT-responders or PDT-nonresponders. All patients were genotyped for the CFH Y402H polymorphism. Results The proportion of PDT-responders was 18/26 (69.2%) in patients homozygous for the CFH Y402H risk allele, 34/50 (68.0%) in heterozygous, and 7/12 (58.3%) in patients with the normal genotype (p=0.520). The median number of PDT treatments of the PDT-responders was three for all the genotypes. Conclusions The dysfunction of the CFH related to the risk of AMD and caused by the Y402H polymorphism does not modify the outcome of PDT. Genotyping for CFH Y402H cannot be used to select patients for this treatment.

The formation of glycohemoglobin, especially the hemoglobin A1c (HbA1c) fraction, occurs when glucose becomes coupled with the amino acid valine in the β-chain of Hb; this reaction is dependent on the plasma concentration of glucose. Since the early 1970s it has been known that diabetics display higher values OF HbA1C because they have elevated blood glucose concentrations. Thus HbA1c has acquired a very important role in the treatment and diagnosis of diabetes mellitus. After the introduction of the first quantitative measurement OF HbA1C, numerous methods for glycohemoglobin have been introduced with different assay principles: From a simple mini-column technique to the very accurate automated high-pressure chromatography and lastly to many automated immunochemical or enzymatic assays. In early days, the results of the quality control reports for HbA1c varied extensively between laboratories, therefore in United States and Canada working groups (WG) of the Diabetes Controls and Complications Trial (DCCT) were set up to standardize the HbA1c assays against the DCCT/National Glycohemoglobin Standardization Program reference method based on liquid chromatography. In the 1990s, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) appointed a new WG to plan a reference preparation and method for the HBA1c measurement. When the reference procedures were established, in 2004 IFCC recommended that all manufacturers for equipment used in HbA1c assays should calibrate their methods to their proposals. This led to an improvement in the coefficient of variation (CV%) associated with the assay. In this review, we describe the glycation of Hb, methods, standardization of the HbA1c assays, analytical problems, problems with the units in which HbA1c values are expressed, reference values, quality control aspects, target requirements for HbA1c, and the relationship of the plasma glucose values to HbA1c concentrations. We also note that the acceptance of the mmol/mol system for HbA1c as recommended by IFCC, i.e., the new unit and reference ranges, are becoming only slowly accepted outside of Europe where it seems that expressing HbA1c values either only in per cent units or with parallel reporting of percent and mmol/mol will continue. We believe that these issues should be resolved in the future and that it would avoid confusion if mmol/mol unit for HbA1c were to gain worldwide acceptance.

Objective This study aimed to determine whether the characteristics of pseudophakic retinal detachment (RD) differ in eyes with and without a neodymium (Nd):YAG laser capsulotomy to identify features that might help to treat capsulotomy patients better. Design The study design was a retrospective cohort study of 129 consecutive eyes, 61 with a capsulotomy and 68 control eyes with an intact posterior capsule, in which a primary rhegmatogenous RD developed after a strictly uncomplicated extracapsular cataract extraction and intraocular lens implantation. Setting The study was conducted in a primary referral center. Main outcome measures Number, type, and location of retinal breaks and type and extent of RD were measured. Results Risk factors predisposing to RD did not differ between the capsulotomy and control group. The median interval from cataract surgery to RD was expectedly longer in the capsulotomy group (4.1 years vs. 1.5 years, P P = 0.05), especially in upper quadrants (82 of 103 vs. 48 of 77, P = 0.024). Capsulotomy eyes also had a trend to have more atrophic holes that caused detachment relative to horseshoe breaks (34 of 103 vs. 15 of 77, P = 0.062). The type and extent of RD were similar in the two groups. Conclusions This pilot study suggests that atrophic holes, particularly in the superior quadrants, may lead to RD preferentially after posterior capsulotomy. Early identification and treatment of such breaks might decrease the number of pseudophakic detachments after capsulotomy.

Purpose: The Y402H polymorphism of the complement factor H (CFH) gene is associated with age-related macular degeneration (AMD) in many populations. The reported genotype)phenotype correlations in the CFH Y402H polymorphism have not been pronounced and no studies on the effect of the polymorphism on the subgroups within wet AMD have been performed. In this study, we wanted to evaluate whether the CFH Y402H polymorphism has an effect on clinical variables in recent exudative AMD lesions. Methods: The study included 172 patients with exudative AMD. The size of AMD lesions and the presence and area of other AMD lesion variables were recorded in fluorescein angiography (FA) and analysed in relation to the Y402H genotypes. Results: The median lesion size (classic + occult choroidal neovascularization [CNV] + serous pigment epithelium detachment [PED] + haemorrhage, if present) was 8.15 mm 2 in patients homozygous for the CFH risk allele (CC), 7.50 mm 2 in heterozygous patients (CT), and 7.05 mm 2 in those with the normal genotype (TT) (p = 0.599). Areas of classic and occult CNV, combined, without serous PED or haemorrhage were 6.37 mm 2 , 5.00 mm 2 and 5.18 mm 2 , respectively (p = 0.407). There was a trend for CC patients to have more frequently minimally classic and less frequently predominantly classic lesion composition than CT or TT subjects. Conclusions: We detected no clear impact of the CFH Y402H polymorphism on recent exudative AMD lesion characteristics. Although the complement cascade is implicated in CNV formation and scarring processes in the retina, the Y402H polymorphism appears relatively neutral in these functions.

Purpose: To determine the 5-year incidence of retinal breaks and retinal detachment (RD) after neodymium:YAG (Nd:YAG) laser posterior capsulotomy and the prophylactic treatment of perioperative retinal breaks. Setting: Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland. Methods: This study design was stage 2 of a prospective nonrandomized interventional case series. Of 341 patients (350 eyes) referred for a first Nd:YAG laser posterior capsulotomy between October 1994 and February 1996, 211 (220 eyes) were examined for retinal breaks before and after capsulotomy (stage 1 of study). Asymptomatic breaks were prophylactically photocoagulated. Of the 211 patients, 106 (113 eyes) were examined at stage 2 a median of 4.9 years after Nd:YAG capsulotomy. The charts of all 341 patients were reviewed for development of RD and retinal breaks. The proportion of patients developing RD was estimated by Kaplan-Meier survival analysis, and the risk for RD was modeled by Cox proportional hazard regression. Results: By 5 years, the overall cumulative proportion of RD in the 341 patients was 2.0% (95% confidence interval [CI], 1.0-4.0). Of the 211 eyes enrolled in stage 1, 2 (1.2%) developed an RD (95% CI, 0.3-4.7). Of 51 fellow eyes that had a capsulotomy and 120 eyes that had a capsulotomy but were not enrolled in stage 1 and were not prophylactically treated, RD occurred in 6 eyes (5.8%; 95% CI, 2.6-13). By univariate Cox regression, the axial length, whether modeled as a continuous variable (hazard ratio [HR] 1.51 for each millimeter increase) or categorized using 25.0 mm as a cutoff (HR 11.1), had the strongest association with RD after Nd:YAG posterior capsulotomy (P = .0002 and P = .0016, respectively). Conclusions: In addition to the capsulotomy, other known risk factors predicted RD after Nd:YAG laser posterior capsulotomy. Close follow-up and prophylactic photocoagulation of preexisting retinal breaks are worth considering, especially in high-risk eyes.