Protocols to determine cytotoxicity of intraocular medical devices should be revised to assure safety. Acute toxic events should be reported to health authorities and scientific media.

PURPOSE:To evaluate choroidal thickness in young subjects using Enhanced Depth Imaging Spectral Domain Optical Coherence Tomography (EDI SD-OCT) describing volume differences between all the defined areas of the Early Treatment Diabetic Retinopathy Study (ETDRS). DESIGN:Prospective, clinical study. METHODS:Seventy-nine eyes of 95 healthy, young (23.8±3.2years), adult volunteers were prospectively enrolled. Manual choroidal segmentation on a 25-raster horizontal scan protocol was performed. The measurements of the nine subfields defined by the ETDRS were evaluated. RESULTS:Mean subfoveal choroidal thickness was 345.67±81.80µm and mean total choroidal volume was 8.99±1.88mm 3 . Choroidal thickness and volume were higher at the superior and temporal areas compared to inferior and nasal sectors of the same diameter respectively. Strong correlations between subfoveal choroidal thickness and axial length (AL) and myopic refractive error were obtained, r = -0.649, p<0.001 and r = 0.473, p<0.001 respectively. Emmetropic eyes tended to have thicker subfoveal choroidal thickness (381.94±79.88µm versus 307.04±64.91µm) and higher total choroidal volume than myopic eyes (9.80± 1.87mm3 versus 8.14±1.48mm3). The estimation of the variation of the subfoveal choroidal thickness with the AL was -43.84µm/mm. In the myopic group, the variation of the subfoveal choroidal thickness with the myopic refractive error was -10.45µm/D. CONCLUSIONS:This study establishes for the first time a normal database for choroidal thickness and volume in young adults. Axial length, and myopic ammetropy are highly associated with choroidal parameters in healthy subjects. EDI SD-OCT exhibited a high degree of intraobserver and interobserver repeatability. M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT INTRODUCTIONThe development of optical coherence tomography (OCT) technology has revolutionized the diagnostic, monitoring and therapeutic approaches to many retinal diseases. Spectral domain OCT (SD-OCT) offers improved axial resolution (3 µm); by providing 19,000 A-scans per second, it shortens examination times, reducing the eye exposure as well as artifacts 1 . The latest development in OCT technology, sweptsource longer-wavelength OCT (SS-OCT), has a longer-band light source than does the conventional instrumentation (1 µm band light source), providing higher penetration through the retinal pigment epithelium (RPE) and allowing for better visualization of the choroid; however, at the present time, SS-OCT use is limited to research.The role of the choroid in a number of diseases, including central serous chorioretinopathy, high myopia, age-related macular degeneration, choroidal melanoma, and polypoidal choroidal vasculopathy, emphasizes the importance of understanding choroidal structure in ocular disease [2][3][4][5] . Indocyanine green has been the best tool for studying choroidal vasculature; however, it does not provide a quantitative evaluation of the layer; other imaging methods such as echography aid in evaluating the layer, and MRI ...

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To determine if short-wavelength automated perimetry (SWAP) provides evidence that indicates early functional losses in ocular hypertensive subjects and to establish a direct comparison with early structural abnormalities in the retinal nerve fiber layer (RNFL). Methods: A total of 160 eyes belonging to 83 patients with ocular hypertension (intraocular pressure Ͼ21 mm Hg and normal results on standard automated perimetry evaluation), on which a SWAP and RNFL study were performed, were examined. One hundred twenty-eight agematched subjects without ocular hypertension were evaluated to establish the 95% and 99% confidence intervals at each of the 76 exploration points of the SWAP test. Results: The RNFL study results were normal in 83 cases (51.8%) and pathologic in 77 cases (48.1%). The SWAP results were pathologic in 57 cases (35.6%). Significant differences (PϽ.001) were observed when comparing the distribution of normal and pathologic SWAP results among the types of defects in the RNFL (focal wedge, diffuse atrophy, and mixed atrophy). Conclusions: Short-wavelength automated perimetry is a useful test for the early detection of visual field losses. It is more sensitive than standard automated perimetry and provides a high association with RNFL assessment, which has proved capable of detecting signs of glaucomatous damage several years before the onset of the typical visual field defects.

Purpose: To evaluate changes in retinal layer thickness in patients with Type 1 diabetes with no diabetic retinopathy after 8 years of follow-up. Methods: Ninety Type 1 diabetes and 60 control eyes were studied. Changes in the retinal nerve fiber layer, ganglion cell layer, and inner nuclear layer thicknesses in all Early Treatment Diabetic Retinopathy Study areas were evaluated. Results: The mean ages were 42.93 ± 13.62 and 41.52 ± 13.05 years in the diabetic and control group, respectively. In 2009, total retinal thickness was higher in diabetic patients; differences were statistically significant in all except the nasal areas. In both groups, the mean foveal thickness remained the same during the 8 years. Among diabetic patients, there was a significant reduction in total retinal thickness in all areas excluding the outer temporal one; controls only in the inferior areas. The thickness loss was due to the thinning of the inner retinal layers (inner nuclear layer, ganglion cell layer, and retinal nerve fiber layer). The controls showed a significant diminution in the retinal nerve fiber layer and in the ganglion cell layer areas. The inner nuclear layer showed a diminution in the diabetes mellitus group. Conclusion: Before the onset of diabetic retinopathy, Type 1 diabetes patients experience a diminution of their inner retinal layer thicknesses over time, supporting the hypothesis of retinal neurodegeneration.