Prevalence of diabetes and diabetic macular edema in patients undergoing senile cataract surgery in Italy: The DIabetes and CATaract study.

BACKGROUND: The purpose of this study is to determine the prevalence of diabetes and diabetic macular edema in patients undergoing senile cataract surgery in Italy. METHODS: It is a prospective, multicenter, cross-sectional study. Thirteen ophthalmic units equally distributed across the Italian territory have been involved in the study. For a period of 3 months, all subjects undergoing phacoemulsification received an Optical Coherence Tompgraphy (OCT) scan and were screened for the anamnestic presence of diabetes. In addition, five selected units collected blood samples from all their patients to measure glycated hemoglobin (HbA1c) levels and detect the presence of occult diabetes (HbA1c > 6.5%). In diabetic patients, levels of retinopathy were measured and diabetic macular edema was considered significant (clinically significant macular edema) when foveal thickness was above 30% of normal levels. RESULTS: A total number of 3657 subjects have been screened. Among them, 20.4% were diabetics. Prevalence of diabetes was significantly higher in males (24.7%) than in females (17%). Levels of HbA1c were tested in a representative sample of 1216 consecutive subjects, and occult diabetes was diagnosed in 4.8% of cases. No significant differences were observed between age groups or different geographic areas. Among diabetic patients, diabetic macular edema of any kind was present in 27.5% (clinically significant macular edema (6.6%)). No significant differences were seen in the prevalence of diabetic macular edema between males and females or between age groups. Among the 745 diabetic patients, no signs of retinopathy were seen in 537 subjects (76.3%), while 101 patients (14.3%) had nonproliferative retinopathy, 13 (1.7%) had nontreated proliferative diabetic retinopathy, and 53 (7.5%) had laser-treated retinopathy. In the entire sample of 3657 subjects, a normal macula was present in 90.9% of cases, diabetic macular edema of any kind in 5.4%, and other maculopathies in 3.4%. CONCLUSION: In this large cohort study on patients undergoing cataract surgery, more than one-fourth were diabetics and more than one-fourth of these had diabetic macular edema. These high prevalences suggest the opportunity to plan an adequate preoperative assessment in all patients in order to reduce the risk of postoperative development or worsening of a sight-threatening complication such as chronic diabetic macular edema.

Placido disk-based topography versus high-resolution rotating Scheimpflug camera for corneal power measurements in keratoconic and post-LASIK eyes: reliability and agreement.

AIM: To compare the repeatability/reproducibility of measurement by high-resolution Placido disk-based topography with that of a high-resolution rotating Scheimpflug camera and assess the agreement between the two instruments in measuring corneal power in eyes with keratoconus and post-laser in situ keratomileusis (LASIK). METHODS: One eye each of 36 keratoconic patients and 20 subjects who had undergone LASIK was included in this prospective observational study. Two independent examiners worked in a random order to take three measurements of each eye with both instruments. Four parameters were measured on the anterior cornea: steep keratometry (Ks), flat keratometry (Kf), mean keratometry (Km), and astigmatism (Ks-Kf). Intra-examiner repeatability and inter-examiner reproducibility were evaluated by calculating the within-subject standard deviation (Sw) the coefficient of repeatability (R), the coefficient of variation (CoV), and the intraclass correlation coefficient (ICC). Agreement between instruments was tested with the Bland-Altman method by calculating the 95% limits of agreement (95% LoA). RESULTS: In keratoconic eyes, the intra-examiner and inter-examiner ICC were >0.95. As compared with measurement by high-resolution Placido disk-based topography, the intra-examiner R of the high-resolution rotating Scheimpflug camera was lower for Kf (0.32 vs 0.88), Ks (0.61 vs 0.88), and Km (0.32 vs 0.84) but higher for Ks-Kf (0.70 vs 0.57). Inter-examiner R values were lower for all parameters measured using the high-resolution rotating Scheimpflug camera. The 95% LoA were -1.28 to +0.55 for Kf, -1.36 to +0.99 for Ks, -1.08 to +0.50 for Km, and -1.11 to +1.48 for Ks-Kf. In the post-LASIK eyes, the intra-examiner and inter-examiner ICC were >0.87 for all parameters. The intra-examiner and inter-examiner R were lower for all parameters measured using the high-resolution rotating Scheimpflug camera. The intra-examiner R was 0.17 vs 0.88 for Kf, 0.21 vs 0.88 for Ks, 0.17 vs 0.86 for Km, and 0.28 vs 0.33 for Ks-Kf. The inter-examiner R was 0.09 vs 0.64 for Kf, 0.15 vs 0.56 for Ks, 0.09 vs 0.59 for Km, and 0.18 vs 0.23 for Ks-Kf. The 95% LoA were -0.54 to +0.58 for Kf, -0.51 to +0.53 for Ks and Km, and -0.28 to +0.27 for Ks-Kf. CONCLUSION: As compared with Placido disk-based topography, the high-resolution rotating Scheimpflug camera provides more repeatable and reproducible measurements of Ks, Kf and Ks in keratoconic and post-LASIK eyes. Agreement between instruments is fair in keratoconus and very good in post-LASIK eyes.

Corneal Astigmatism Measurement by Ray Tracing Versus Anterior Surface-Based Keratometry in Candidates for Toric Intraocular Lens Implantation.

PURPOSE: To compare corneal astigmatism derived from total corneal refractive power (CATCRP), a ray-tracing method, with that derived from simulated keratometry (CASimK), an anterior surface-based method, in candidates for toric intraocular lens (IOL) implantation. DESIGN: Reliability analysis. METHODS: In 1 eye of 200 consecutive patients (mean age 71 ± 9 years) with cataract, a Pentacam HR (Oculus) was used to measure CATCRP and CASimK. Eyes with CATCRP >1 diopter (D) were defined as candidates for toric IOL implantation. The estimation difference between CATCRP and CASimK was analyzed by calculating the arithmetic, absolute, and vector differences between the 2 methods. RESULTS: Seventy-seven candidates were identified. In the candidates, CASimK was <1 D in 22% of cases and underestimated the astigmatism magnitude, on average, by -0.15 ± 0.34 D. The mean absolute and vector difference between CATCRP and CASimK was 0.31 ± 0.29 D and 0.30 ± 0.29 D × 180 degrees, respectively. The absolute and vector differences between the 2 methods were >0.50 D in 21 of 77 (27.2%) and 25 of 77 (32.5%) eyes, respectively; the proportions were significantly (P < .001) higher than in the eyes with CATCRP ≤1 D (0.8% and 9.8%, respectively). The difference in steep meridian alignment between CATCRP and CASimK was >5 degrees in 22.1% and >10 degrees in 2.6% of cases. CONCLUSION: The difference between CATCRP and CASimK, as calculated by Pentacam HR, is greater in candidates for toric IOL implantation than in the general population. That difference considerably influences the candidate and toric IOL power selection in a large proportion of cases.

Retinal nerve fibre layer and macular thickness analysis with Fourier domain optical coherence tomography in subjects with a positive family history for primary open angle glaucoma.

AIM: To detect early structural changes of retinal nerve fibre layer (RNFL) and macular ganglion cell complex (GCC) in subjects with a positive family history for primary open angle glaucoma (POAG) using Fourier domain optical coherence tomography (FD-OCT) (RTVue-100). METHODS: This was a cross-sectional observational study. First and second degree relatives of POAG patients, healthy subjects, and subjects with preperimetric glaucoma (PPG) without a family history for glaucoma, were enrolled. All participants underwent complete ophthalmic examination, visual field test and FD-OCT (RTVue-100) imaging. Average RNFL and GCC thicknesses were measured and a pattern analysis was applied to the GCC map. Analysis of variance (ANOVA), least significant difference post-hoc test, and multiple ANOVA were used. RESULTS: The final analysis included 271 eyes divided into several groups: 163 eyes of first and second degree relatives (85 healthy, 40 with ocular hypertension and 38 with PPG); and 108 eyes of subjects without a positive family history (60 healthy and 48 PPG). RNFL and GCC thickness values of these five groups were statistically different (p<0.001). RNFL superior, GCC average, GCC superior, and GCC inferior were found to be significantly thinner and the global loss volume was higher in normal relatives than in healthy subjects without a positive family history of POAG (p=0.04, p=0.001, p=0.005, p=0.004, p=0.009). RNFL and GCC thicknesses obtained by dividing the family members by the degree of consanguinity showed statistically significant thinning in siblings of glaucomatous subjects than in offspring. CONCLUSIONS: Our study shows that the eyes of subjects with a positive family history for POAG have significantly thinner RNFL and GCC than normal eyes and a more accurate follow-up has to be performed.

Morphology of optic disc through heidelberg retina tomograph in retinal vein occlusions alone or in combination with primary open angle glaucoma.

PURPOSE: To evaluate the morphology of optic discs in eyes suffering from retinal vein occlusion (RVO) alone or in combination with primary open-angle glaucoma (POAG). METHODS: Prospective, observational study. 48 consecutive patients were enrolled, 30 with unilateral RVO diagnosis, 18 with unilateral retinal vein occlusion (RVO) associated with POAG. We divided RVOs on the basis of occlusion site: arterio-venous crossing (AV-RVO), optic cup (OC-RVO), optic nerve (ON-RVO) with head nerve swelling (ONHS-RVO) or without it (NONHS-RVO). A control group of 25 patients who were sex and age matched was selected. RESULTS: Comparing the fellow eyes of the patients with RVO and control healthy eyes, no differences emerged in cup/disc ratio but they came out for the HRT values in Rim Area, cup shape measure and height variation contour (p<0.05). The most frequent occlusion site was at the level of an arteriovenous crossing in patients not suffering from POAG (36.7%) and at the level of the optic cup in patients with RVO and POAG (50%). In the RVO group without POAG, the OC-RVO subgroup has shown an higher cup area (0.366±0.094) and cup/disc area ratio (0.184±0.063), a lower rim volume (0.374±0.021) and a different cup shape measure (-0.221±0.066) (p<0.05) compared with the AV and NONHS sites. Compared with NONHS group differences emerged also for the fibres parameters and in the height variation contour (0.346±0.081). Also in the RVO group with POAG significant differences (p<0.05) have been surveyed between OC-RVO and other occlusion sites in cup area (0.119±0.029), cup/disc area ratio (0.532±0.09), rim volume (0.374±0.07), cup/shape measure (-0.079±0.013). CONCLUSIONS: Classification of the analyzed parameters on the basis of the occlusion site provides a basis for which clinical decisions and research on causal factors in future studies can be based on.