Do myopes have deficits in peripheral flicker sensitivity?

Purpose: Signals from the peripheral retina are important for myopia development. Unlike temporal vision, deficits in peripheral spatial visual functions of myopes have been investigated previously. This study investigated temporal contrast thresholds in emmetropes and myopes at different retinal eccentricities.Methods: Forty-four young adults (mean age 23 ± 3 years) including 21 emmetropes (Spherical Equivalent (SE): +0.01 ± 0.30D) and 23 myopes (SE: -3.98 ± 2.41D) participated in this prospective study. Flicker modulation thresholds (FMT) were determined monocularly (right eye) for 15 Hz flicker stimulus at 0°, nasal (23°, 10°) and temporal (-23°, -10°) retinal eccentricities along the horizontal meridian. FMTs were measured psychophysically using 5-adaptive interleaved staircases and threshold was taken as the average of the last 6 reversals.Results: In both the groups (emmetropes and myopes), there was a naso-temporal asymmetry in FMTs with higher thresholds in the far temporal retina (Median; Interquartile range: 40.97%; 17.06) than the nasal retina (28.07%; 9.36) (p < 0.001). Flicker modulation thresholds were significantly higher in myopes (30.58%; 12.15) compared to emmetropes (26.77%; 7.74; p = 0.04) at far nasal retina (23°), while at other eccentricities there was no effect (p > 0.05). Further sub-analysis revealed only high myopes (34.48 %, 21.9) showed significantly higher FMT compared to emmetropes (26.77%; 7.74; p = 0.04).Conclusion: Greater FMTs were seen in high myopes than that of emmetropes in the nasal retina. Further studies exploring the structural aspects of the myopic eye with FMT would provide a better understanding of role of flicker sensitivity in myopiogenesis. (AU)

Do myopes have deficits in peripheral flicker sensitivity?

PURPOSE: Signals from the peripheral retina are important for myopia development. Unlike temporal vision, deficits in peripheral spatial visual functions of myopes have been investigated previously. This study investigated temporal contrast thresholds in emmetropes and myopes at different retinal eccentricities. METHODS: Forty-four young adults (mean age 23 ± 3 years) including 21 emmetropes (Spherical Equivalent (SE): +0.01 ± 0.30D) and 23 myopes (SE: -3.98 ± 2.41D) participated in this prospective study. Flicker modulation thresholds (FMT) were determined monocularly (right eye) for 15 Hz flicker stimulus at 0°, nasal (23°, 10°) and temporal (-23°, -10°) retinal eccentricities along the horizontal meridian. FMTs were measured psychophysically using 5-adaptive interleaved staircases and threshold was taken as the average of the last 6 reversals. RESULTS: In both the groups (emmetropes and myopes), there was a naso-temporal asymmetry in FMTs with higher thresholds in the far temporal retina (Median; Interquartile range: 40.97%; 17.06) than the nasal retina (28.07%; 9.36) (p < 0.001). Flicker modulation thresholds were significantly higher in myopes (30.58%; 12.15) compared to emmetropes (26.77%; 7.74; p = 0.04) at far nasal retina (23°), while at other eccentricities there was no effect (p > 0.05). Further sub-analysis revealed only high myopes (34.48 %, 21.9) showed significantly higher FMT compared to emmetropes (26.77%; 7.74; p = 0.04). CONCLUSION: Greater FMTs were seen in high myopes than that of emmetropes in the nasal retina. Further studies exploring the structural aspects of the myopic eye with FMT would provide a better understanding of role of flicker sensitivity in myopiogenesis.

Quantitative Parameters from OCT Angiography in Patients with Diabetic Retinopathy and in Those with Only Peripheral Retinopathy Compared with Control Participants.

Purpose: To describe the differences in a range of quantitative OCT angiography (OCTA) metrics across early stages of diabetic retinopathy (DR), providing robust effect estimates as well as sensitivity and specificity. Design: Cross-sectional study with population-based sampling. Participants: Four hundred forty-one eyes from 296 individuals: 328 control eyes (no diabetes mellitus [DM] and no DR), 55 eyes with DM and no DR, and 58 eyes with early nonproliferative DR. Methods: Multimodal retinal imaging included color fundus photography, color Optomap ultra-widefield imaging, and spectral-domain OCT (Spectralis OCT2; Heidelberg Engineering GmbH) with the OCTA module. All images were graded for the presence and severity of DR features. OCTA images were assessed manually for inclusion based on quality. Binary OCTA metrics were assessed after 3-dimensional projection artifact removal including from the nerve fiber layer vascular plexus, superficial vascular plexus (SVC), and deep vascular plexus (DVC) by Early Treatment Diabetic Retinopathy Study (ETDRS) grid, foveal avascular zone (FAZ) area, FAZ minimum and maximum diameter, perimeter length, and circularity. Main Outcome Measures: Diabetes mellitus and DR status and presence or absence of DR in the retinal periphery. Results: The reduction in vessel densities in participants with DM and manifest DR compared with control participants tended to be twice that of those with DM, but no DR, compared with control participants. Some evidence of spatial heterogeneity in vessel reductions was found in those yet to develop DR, whereas those with manifest DR had significant reductions across the ETDRS grid. The FAZ perimeter and circularity were impacted most significantly by DM, and those with DR showed decreased multispectral fractal dimensions compared with control participants. Eyes with peripheral DR had reduced vessel density compared with those with DM and no DR only in the superior outer, temporal inner, and temporal outer regions in the DVC and SVC. The area under the receiver operating characteristic curve ranged between 0.48 and 0.73. Conclusions: Significant differences in OCTA metrics can be found in those with DM before manifest DR using commercially available equipment with minimal image postprocessing. Although diagnostic performance was poor, these metrics may be useful for measuring change over time in clinical trials.

Widefield optical coherence tomography angiography in diabetic retinopathy.

AIMS: To evaluate superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) perfusion in macular and near/mid periphery regions in diabetic patients using widefield swept-source optical coherence tomography angiography (WSS-OCTA). METHODS: Ninety-four diabetic patients (94 eyes) classified as diabetics without diabetic retinopathy (no DR) (25 eyes), mild DR (23 eyes), moderate/severe DR (26 eyes), proliferative DR (20 eyes) and a control group of 25 healthy subjects (25 eyes) were imaged with the WSS-OCTA system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). Quantitative analysis was performed in the macular and peripheral regions. The main outcome measures were perfusion density (PD) and vessel length density of SCP, DCP and CC. RESULTS: Peripheral retina (all sectors) showed lower SCP and DCP PD compared to the macular region (p < 0.001). In diabetics without DR and DR in different stages, SCP and DCP PD significantly decreased at advancing stages of DR (p < 0.001). At DCP level, central PD was significantly directly related to peripheral PD (superior, R = 0.682 and 0.479; temporal, R = 0.918 and 0.554; inferior, R = 0.711). A good sensitivity and an excellent specificity were found in terms of prediction of disease worsening, especially for central and temporal sectors in all plexuses and for all sectors both central and peripheral of DCP. CONCLUSIONS: The widefield OCTA is useful for the study of central and peripheral retina in diabetic patients with or without diabetic retinopathy, assessing good correlation between central and peripheral retina.

Hallazgos periféricos en pacientes con degeneración macular relacionada con la edad avanzada / Peripheral findings in patients with age-related macular degeneration

Objetivo: Explorar la asociación entre la presencia de cambios degenerativos en la periferia retiniana de pacientes con diagnóstico clínico de Degeneración Macular Relacionada con la Edad (DMRE), evaluados con fotografía de fondo de ojo a color (FP), angiografía fluoresceínica (FA) y autofluorescencia (FAF), y las etapas más avanzadas de la enfermedad. Métodos: Estudio descriptivo, transversal con intención analítica, en el cual se evaluaron las imágenes de campo amplio obtenidas mediante FP, FA, y FAF con oftalmoscopía de láser confocal con la Optomap 200TX, de todos los pacientes con diagnóstico clínico de DMRE, para un total de 94 pacientes (188 ojos) que aceptaron participar en el estudio, y que acudieron a la Clínica Oftalmológica de Antioquia (CLOFAN) entre agosto y septiembre del 2016, con diagnóstico clínico de DMRE. La variable desenlace fue presencia de DMRE avanzada. Resultados: Se incluyeron imágenes de 130 ojos de 70 pacientes. La edad media fue 72,1 años (DE±9,5 años). El 20,8% de los pacientes eran pseudofáquicos. El 52,9%, 32,9% y 37,1% tenían historia de HTA, dislipidemia y hábito tabáquico positivo, respectivamente. Se observó una asociación estadísticamente significativa entre DMRE avanzada y el antecedente de DMRE en la familia (p<0,05, OR=2,4, IC=1,1-6,2), la presencia de cambios degenerativos en la periferia en FP (p<0,001, OR=5,71, IC=1,8-17,7), FA (p<0,05, OR=3,1, IC=0,9-10,1) y FAF (p<0,001,OR=10,52, IC=0,63-8,13). En el análisis multivariado solo la presencia de lesiones en FP se mantuvo asociada significativamente con la presencia de DMRE avanzada. Conclusiones: La presencia de cambios degenerativos en periferia se asocian 4,71 veces más con la DMRE avanzada, y por tanto, la presencia de éste tipo de lesiones podría ser predictora de progresión. Se requieren estudios prospectivos que permitan determinar causalidad y contribuir a la comprensión de la patogénesis de la DMRE.

Purpose: To explore the association between the presence of degenerative changes in the retinal periphery of patients with clinical diagnosis of AMD, evaluated with color fundus photography (FP), fluorescein angiography (FA) and autofluorescence (FAF), and the more advanced stages of the disease. Methods: A descriptive, cross-sectional study with analytical intent, in which wide fi eld images obtained by PF, AF, and FAF using confocal laser ophthalmoscopy with Optomap 200TX, all patients with a clinical diagnosis of AMD, for a total of 94 patients (188 eyes) who attended the Clínica oftalmológica de Antioquia (CLOFAN) between August and September of 2016, with clinical diagnosis of AMD, were analyzed. Th e outcome variable was advanced age related macular degeneration. Results: Images of 130 eyes of 70 patients were included. Th e mean age was 72.1 years (SD ± 9.5 years). It was observed that 20.8% were pseudophakic. 52.9%, 32.9% and 37.1% had a history of hypertension, dyslipidemia and a positive smoking habit, respectively. Th ere was a statistically signifi cant association between advanced AMD and family history of AMD (p <0.05, OR=2.4, CI=1.1-6.2), the presence of degenerative changes in the FP (P <.001, OR=5.71, CI=1.8-17.7), FA (p <0.05, OR=3.1, CI=0.9-10.1) and FAF (p <0.001, OR=10.52, CI=0.63-8.13). In the multivariate analysis only the presence of lesions in FP remain signifi cantly associated with the presence of advanced AMD. Conclusions: Th e presence of degenerative changes in periphery are associated 4.71 times more with advanced AMD, and therefore, the presence of this type of lesions could be predictive of progression. Prospective studies are required to determine causality and contribute to the understanding of the pathogenesis of AMD.