Patients with AD showed a significant thickness reduction in global and temporal superior quadrants in pRNFL and in superior pericentral and peripheral sectors of RT. These findings may reflect a peripapillary and retinal changes characteristic of AD, suggesting the importance of SD-OCT as a potential adjuvant in early diagnosis of AD. Further studies are needed to understand which retinal layers and macular sectors are more useful as potential ocular biomarker over time in AD.

IntroductionThe purpose of this study was to measure and to compare macular choroidal thickness (CT) between patients with mild Alzheimer's disease (AD), patients without AD, and elderly patients.MethodsCT was measured manually in 13 locations at 500-μm intervals of a horizontal and a vertical section from the fovea. Linear regression models were used to analyze the data.ResultsFifty patients with a diagnosis of mild AD (73.1 years), 152 patients without AD (71.03 years), and 50 elderly without AD (82.14 years) were included. In the AD patients, CT was significantly thinner in all 13 locations (P < .001—comparing with age-match group), and comparing with the elderly group, a more pronounced difference was found in two locations temporal to the fovea.DiscussionPatients with AD showed a significant choroidal thinning even when compared with elderly subjects. The reduction of CT may aid in the diagnoses of AD, probably reflecting the importance of vascular factors in their pathogenesis.

Retinal thickness profile is not linear throughout disease duration. Even in the absence of funduscopic disease, PR layer in diabetic patients seems to differ from nondiabetic subjects, thus suggesting that some form of neurodegeneration may take place before clinical signs of vascular problems arise.

Purpose: To compare choroidal thickness (CT) between patients with systemic lupus erythematosus (SLE) without ophthalmologic manifestations and a control group. To study the effects in CT of disease duration, activity index, medication and systemic comorbidities. Methods: Cross-sectional study where spectral-domain optical coherence tomography with enhanced depth imaging was used to measure CT in 13 locations, subfoveally and at 500-µm intervals along a horizontal and a vertical section from the fovea. Linear regression models were used. Results: Sixty-eight SLE patients and fifty healthy controls were enrolled. CT multivariable analysis revealed lower values in SLE patients (12.93-26.73 µm thinner) in all locations, except the inferior quadrants (6.48-10.44 µm thicker); however, none of these results reached statistical significance. Contrary to the control group, the normal topographic variation in CT between macular quadrants and from the center to the periphery was not observed in the SLE group. Multivariable analysis in the SLE group alone revealed a significant negative association with anticoagulants (50.10-56.09 µm thinner) and lupus nephritis (40.79-58.63 µm thinner). Contrary to controls, the CT of SLE patients did not respond to changes in mean arterial pressure. Conclusion: CT in SLE appears to be thinner, particularly in the subset of patients with nephritis and taking anticoagulants, suggesting more advanced systemic vascular disease. Choroidal responses to hemodynamic changes may also be altered in SLE.

Nonarteritic anterior ischemic optic neuropathy (NA-AION) is the most common nonglaucomatous optic neuropathy in adults over 50 years of age. It is usually related to cardiovascular risk factors. The primary objective of this study was to evaluate choroidal thickness in patients with chronic NA-AION, and the secondary objective was to evaluate macular thickness in these patients. This cross-sectional study compared two groups: group 1 included 20 eyes of 20 patients with chronic NA-AION, and group 2 included 31 eyes of 31 healthy controls. In both groups, the choroidal thickness was measured using the enhanced depth imaging program of Heidelberg Spectralis Õ optical coherence tomography (Heidelberg Engineering, Heidelberg, Germany). The macular thickness was also measured using the automatic software of the same device. The mean follow-up time after NA-AION in group 1 was 57.17 ± 26.92 months. The mean choroidal thickness of the posterior pole was 244.38 ± 61.03 mm in group 1 and 214.18 ± 65.97 mm in group 2 (p = 0.004). The mean macular thickness was higher in group 2. Macular thickness is reduced in eyes that had an episode of NA-AION, whereas choroidal thickness is generally higher in these eyes when compared with normal eyes. The increase in choroidal thickness may be due to a local dysfunction in vascular autoregulatory mechanisms, which may predispose to ischemic phenomena.

PURPOSE: To identify changes in choroidal thickness (CT) and all retinal layers of diabetic patients without diabetic retinopathy (DR) after 1 year of follow-up. DESIGN: Prospective observational cohort study. METHODS: Overall, 125 diabetic patients without DR were included. Two visits were scheduled: the first visit (V1) and a second visit after 12 months (V2). At both visits, patients received a complete ophthalmologic evaluation that included OCT. Each retinal layer thickness was calculated for 9 ETDRS sectors, and CT was measured at 13 locations. Generalized linear mixed-effects models were used.RESULTS: Of the 125 patients, 103 completed the study, and 9 of the 103 developed DR (8.7%). CT was significantly higher at V2 than at V1, with an average value of 10-17 mm at almost half the locations (500, 1000, and 1500 mm temporal; 500 and 1000 mm nasal; and 1000 mm superior to the fovea) (P < .001-.003). The thicknesses of the ganglion cell layer (I3 and N6 sectors), inner plexiform layer (S6 and N6 sectors), inner nuclear layer (T6 and N6 sectors), and outer plexiform layer (S6 sector), as well as the overall retinal thickness (RT) (S3, N3, I3, S6, and T6 sectors), were decreased at V2 (P < .001). Visible retinopathy was negatively associated with overall RT (central, S3, T3, I3, and N3 sectors, P [ .004-.024) and the thickness of the ONL (T6 and I6 sectors, P [ .007 and P [ .009) and photoreceptor layer (N6 sector, P [ .038). The presence of DR decreased the overall RT by 13.04-16.63 mm.CONCLUSIONS: Diabetic patients without DR showed a thicker choroid and a thinner retina, particularly in inner layers, after 1 year of follow-up. These structural changes may correspond to the early neurodegenerative phase of DR. ( 1 Of the 415 million diabetic patients worldwide in 2015, over one third will develop DR in their lifetime.2 The RETINODIAB study, an epidemiologic study that investigated the prevalence and progression rates of DR based on a national screening community program in Portugal, identified a 16.3% prevalence rate of DR and a 4.6% incidence rate of any DR within the first year in diabetic patients without retinopathy at baseline. 3,4

Alzheimer's disease (AD) is a prevalent, long-term progressive degenerative disorder with great social impact. It is currently thought that, in addition to neurodegeneration, vascular changes also play a role in the pathophysiology of the disease. Visual symptoms are frequent and are an early clinical manifestation; a number of psychophysiologic changes occur in visual function, including visual field defects, abnormal contrast sensitivity, abnormalities in color vision, depth perception deficits, and motion detection abnormalities. These visual changes were initially believed to be solely due to neurodegeneration in the posterior visual pathway. However, evidence from pathology studies in both animal models of AD and humans has demonstrated that neurodegeneration also takes place in the anterior visual pathway, with involvement of the retinal ganglion cells' (RGCs) dendrites, somata, and axons in the optic nerve. These studies additionally showed that patients with AD have changes in retinal and choroidal microvasculature. Pathology findings have been corroborated in in-vivo assessment of the retina and optic nerve head (ONH), as well as the retinal and choroidal vasculature. Optical coherence tomography (OCT) in particular has shown great utility in the assessment of these changes, and it may become a useful tool for early detection and monitoring disease progression in AD. The authors make a review of the current understanding of retinal and choroidal pathological changes in patients with AD, with particular focus on invivo evidence of retinal and choroidal neurodegenerative and microvascular changes using OCT technology.

Background Systemic lupus erythematosus (SLE) is a chronic, autoimmune and multisystemic disease. Recent studies with functional and structural magnetic resonance imaging and cognitive tests report an unexpectedly high frequency of central nervous system involvement, even in patients with asymptomatic SLE. The purpose of this study was to identify early signs of retinal neurodegeneration by comparing the thickness of the peripapillary retinal nerve fiber layer (pRNFL) and all macular layers between patients with SLE without ophthalmologic manifestations and healthy controls. The effect of disease duration and systemic comorbidities was also studied. Methods Cross-sectional study, in which all participants underwent a complete ophthalmologic evaluation including retinal segmentation analysis with spectral domain-optical coherence tomography. Patients with SLE also received a detailed autoimmune disease specialist evaluation to assess the disease activity state and systemic involvement. For pRNFL thickness, the global and six peripapillary sectors were determined. Each macular layer thickness was determined in the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields. A multiple linear regression analysis was performed to control for the effect of potential demographic, ophthalmic and systemic confounders. A second multivariable analysis, including patients with SLE only, was performed to assess the effect of disease-specific variables on the outcome measures. Results Sixty-eight eyes of 68 patients with SLE and 50 eyes of 50 healthy controls were considered. The pRNFL was significantly thinner in the SLE group globally (p = 0.026) and in the temporal superior (p = 0.007) and temporal (p = 0.037) sectors. In patients with SLE, chronic medication for hypercholesterolemia, hypertension and anticoagulants were associated with a significant thinning of the pRNFL. Patients with SLE presented significant thinning in the photoreceptor layer in five ETDRS areas (p < 0.05). Shorter disease duration was associated with greater photoreceptor thinning in all ETDRS subfields. Neuropsychiatric SLE, higher disease activity and cardiovascular risk factors were associated with a thinner photoreceptor layer. No differences were observed in overall retinal thickness or the remaining macular layers. Conclusion Patients with SLE present early signs of retinal neurodegeneration, as evidenced by a reduction in the photoreceptor layer and pRNFL. These signs are more pronounced in patients with higher cardiovascular risk burden or neuropsychiatric involvement.