Distance between the center of the FAZ measured automatically and the highest foveal bulge using OCT-angiography in elderly healthy eyes

The center of the fovea, termed the foveola, is the area of highest visual acuity, has the highest density of cone photoreceptors. We investigated the distance between the automatically-determined center of the foveal avascular zone (FAZ) and the manually-determined highest foveal bulge (FB) point using single swept-source optical coherence tomography angiography (OCTA) instrument. This cross-sectional study included 49 eyes of 49 individuals (34 women and 15 men; median age: 68 years) with no history of ocular disorders. The FAZ in the superficial capillary plexus was automatically determined using the Kanno–Saitama macro method, and the center of the FAZ was automatically determined using ellipse approximation. Another candidate foveal center, the highest FB point, was determined manually on the serial cross-sectional B-scan images. As a result, the foveal center was manually identified as the highest FB point on B-scan OCTA images. The center of the FAZ was more likely to be located inferior to the highest FB point (p = 0.031). In participants with a total (linear) distance of more than 50 μm between the center of the FAZ and the highest FB point, the displacement was significantly more in the horizontal direction than in the vertical direction (p = 0.017). These results can be applicable to further studies regarding the spatial relationships between the center of the FAZ and the highest FB point in various macular diseases or previously-treated eyes.

Choroidal remodeling distribution pattern in the macular region in Chinese young patients with myopia

Background The pathogenesis of myopia has been found to be associated with the blood supply of the choroid. This study aimed to determine the relationship between the distribution pattern of choroidal remodeling and the degree of myopia in young patients. Methods Young patients (age < 18 years) with the spherical equivalent of less than − 12 diopters (D) were included. Spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) modality was used to measure the choroidal thickness (CT) and choroidal vascularity index (CVI) in the macular regions. CVI was calculated as the proportion of luminal area to choroidal area and was measured within 1 mm and 3 mm nasal (N1 and N3), temporal (T1 and T3), superior (S1 and S3), and inferior (I1 and I3) to the foveal center. CVI was compared across different ages (i.e., 5 ~ 9 years, 10 ~ 13 years, and 14 ~ 18 years), axial lengths (ALs) (i.e., 21.00 ~ 25.00 mm and 25.01 ~ 29.00 mm), and spherical equivalents (SEs) (i.e., SE > -0.5D, − 0.5 ~ − 3.0D, − 3.01 ~ − 6.0D, and < − 6.0D). Linear regression analysis was applied to assess the association between independent (i.e., age, AL, SE, and intraocular pressure) and dependent variables (i.e., CVI of different regions). Results One hundred sixty-four eyes from 85 volunteers were included. The mean CT in the central foveal was 269.87 ± 63.32 μm (93.00 μm to 443.00 μm). The mean subfoveal-CVI was 67.66 ± 2.40% (57.84 to 79.60%). Multiple linear regression results revealed significant correlations between SE and T1-CVI (p < 0.05, r2 = 0.082, β = 0.194), N1-CVI (p < 0.05, r2 = 0.039, β = 0.212). Simple linear regression results revealed that T1-CVI (p < 0.05, r2 = 0.09) and T3-CVI (p < 0.05, r2 = 0.05) were negatively correlated with SE; N1-CVI (p < 0.05, r2 = 0.05) and N3-CVI (p < 0.05, r2 = 0.04) were negatively correlated with SE. Conclusions CVI in the horizontal meridian underwent the largest change as myopia worsened. Temporal and nasal CVIs within the r = 1 mm, and r = 3 mm subfoveal range were positively associated with the degree of myopia in young patients. The CVI value may be used to assess the vascular status of the choroid and be a potential marker of myopic progression.

Hydroxychloroquine’s Early Impact on Cone Density

Purpose. To evaluate early effects of hydroxychloroquine (HCQ) on the retina using adaptive optics (AO). Methods. This was a prospective observational single-center study of 29 eyes of 29 patients who had been treated with HCQ for the first time and followed with AO for a minimum of two years. Cone counting was performed in 4 quadrants, nasal, temporal, superior, and inferior, at 0.75 mm from the foveal center. The changes of cone density on AO, visual acuity, and foveal thickness within two years of use were analyzed. The changes of mean cone density of patients whose cumulative dose was over 200 g in 2 years were also assessed. We evaluated the correlation between cone density and cumulative dose of HCQ. Results. There was no significant decrease in cone density in the first 2 years of HCQ use. VA and foveal thickness did not show obvious change, either. Among 9 patients whose cumulative dose was over 200 g in 2 years, the mean cone density showed no significant change at 6, 12, 18, and 24 months compared with baseline ( P = 0.381 , P = 0.380 , P = 0.281 , and P = 0.534 , respectively). There was no correlation between cone density and cumulative dose of HCQ at two years (Spearman’s correlation coefficient, r = −0.0553, P = 0.780 ; n = 29). Conclusion. AO showed no change in cone density in the first two years of HCQ use.

Distance between the center of the foveal avascular zone measured automatically and the highest foveal bulge using OCT angiography

The center of the fovea, termed the foveola, is the area of highest visual acuity, has the highest density of cone photoreceptors, and is the center of the foveal avascular zone (FAZ). We investigated the distance between the automatically-determined center of the foveal avascular zone (FAZ) and the manually-determined highest foveal bulge (FB) point using swept-source optical coherence tomography angiography (OCTA). This cross-sectional study included 49 eyes of 49 individuals (34 women and 15 men; median age: 68 years) with no history of ocular disorders. The FAZ in the superficial capillary plexus was automatically determined using the Kanno-Saitama Macro method, and the center of the FAZ was automatically determined using ellipse approximation. The foveal center was manually identified as the highest FB point on B-scan OCTA images. The center of the FAZ was more likely to be located inferior to the highest FB point. In participants with a combined distance of more than 50 µm between the center of the FAZ and the highest FB point, the displacement was significantly more in the horizontal direction than in the vertical direction (p = 0.017). These results can be applicable to further studies regarding the spatial relationships between the center of the FAZ and the highest FB point in various macular diseases or previously-treated eyes.

Management of optic disc pit-associated maculopathy: A case series from a tertiary referral center

Purpose: To report outcomes of pars plana vitrectomy (PPV) combined with internal limiting membrane (ILM) stuffing technique in patients with optic disc pit associated maculopathy (ODP-M). Methods: Data including best-corrected visual acuity (BCVA), central macular thickness (CMT), foveal center point thickness (FCP), and maximum height of fluid (max_fluid) (intraretinal or subretinal) were collected from the medical records of the patients. Results: Six eyes of six patients with a mean age of 28.0 ± 17.68 years (range: 9–53 year) underwent PPV + ILM plug surgery. The mean follow-up duration was 25.62 ± 26.11 months (range: 11.80–78.00 month) duration. The mean BCVA increased from 1.25 ± 1.04 logMAR (20/355, Snellen equivalent) to 0.86 ± 1.09 logMAR (20/144, Snellen equivalent) at last follow-up ( p = 0.043). Compared to baseline, CMT, FCP, and max_fluid significantly decreased at all visits after the surgery ( p < 0.05 for all visits). At last follow-up, 66.6% of the eyes (four eyes) showed complete resolution of fluid at a mean of 5.25 ± 4.99 months (range: 1–12 months) after the surgery. Conclusion: PPV with ILM plug seemed to be an effective surgical technique in ODP-M. Studies with longer follow-up and higher number of patients are needed to confirm our results.

Foveal Pit Morphology Characterization: A Quantitative Analysis of the Key Methodological Steps

Disentangling the cellular anatomy that gives rise to human visual perception is one of the main challenges of ophthalmology. Of particular interest is the foveal pit, a concave depression located at the center of the retina that captures light from the gaze center. In recent years, there has been a growing interest in studying the morphology of the foveal pit by extracting geometrical features from optical coherence tomography (OCT) images. Despite this, research has devoted little attention to comparing existing approaches for two key methodological steps: the location of the foveal center and the mathematical modelling of the foveal pit. Building upon a dataset of 185 healthy subjects imaged twice, in the present paper the image alignment accuracy of four different foveal center location methods is studied in the first place. Secondly, state-of-the-art foveal pit mathematical models are compared in terms of fitting error, repeatability, and bias. The results indicate the importance of using a robust foveal center location method to align images. Moreover, we show that foveal pit models can improve the agreement between different acquisition protocols. Nevertheless, they can also introduce important biases in the parameter estimates that should be considered.

Choroidal Remodeling Distribution Pattern in the Macular Region in Chinese Young Patients with Myopia

Background: The pathogenesis of myopia has been found to be associated with the blood supply of the choroid. This study aimed to determine the relationship between distribution pattern of the choroidal remodeling and the degree of myopia in young patients.Methods: Young patients (age < 18 years) with spherical equivalent of less than -12 diopters (D) were included. Spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) modality was used to measure the choroidal thickness (CT) and choroidal vascularity index (CVI) in the macular regions. CVI was calculated as the proportion of luminal area to choroidal area and was measured within 1 mm and 3 mm nasal (N1 and N3), temporal (T1 and T3), superior (S1 and S3), and inferior (I1 and I3) to the foveal center. CT and CVI were compared across different ages (i.e., 5~9 years, 10~13 years, and 14~18 years), axial lengths (ALs) (i.e., 21.00~25.00mm and 25.01~29.00mm), and spherical equivalents (SEs) (i.e., SE>-0.5D, -0.5~-3.0D, -3.01~-6.0D, and <-6.0D). Multiple linear regression was applied to examine the associations amongst age, AL, SE, and CVI of different locations.Results: 164 of 172 eyes from 85 volunteers were included. The mean CT in the central foveal was 269.87 ± 63.32µm (ranging from 93.00µm to 443.00µm). The mean sub foveal-CVI was 67.66 ± 2.40% (ranging from 57.84% to 79.60%). Multiple linear regression results revealed significant correlations between SE and T1-CVI (p < 0.05, r2= 0.082, β= 0.194), N1-CVI (p < 0.05, r2= 0.039, β= 0.212). Simple linear regression results revealed that T1-CVI (p < 0.05, r2 = 0.09) and T3-CVI (p < 0.05, r2 = 0.05) were negatively correlated with SE; N1-CVI (p < 0.05, r2 = 0.05) and N3-CVI (p < 0.05, r2 = 0.04) were negatively correlated with SE. Conclusions and Relevance: CVI in the horizontal meridian underwent the largest change as myopia worsened. Temporal and nasal CVIs within the r =1mm and r=3mm sub foveal range were positively associated with degree of myopia in young patients. The CVI value may be used to assess the vascular status of the choroid and be a potential marker of myopic progression.

Disorganization of the retinal inner layers as a predictor of visual acuity in eyes with macular edema secondary to uveitis

AIM: To assess the correlation between disorganization of the retinal inner layers (DRIL) and best-corrected visual acuity (BCVA) in patients with uveitis and macular edema (UME) who underwent systemic treatment using optical coherence tomography (OCT). METHODS: A retrospective clinical study of 23 patients (30 eyes) with DRIL and 23 patients (31 eyes) without DRIL secondary to UME were included. All patients underwent comprehensive ophthalmic examinations at baseline, 3, 6, and 12mo after local and systemic treatment. The OCT-based parameters included foveal center point thickness (FCPT), mean thickness (MT), and diameters of DRIL in horizontal and vertical directions. BCVA and OCT-based parameters were compared between the two groups. The relationship between each OCT parameter and BCVA was evaluated using linear correlation and regression analysis. RESULTS: At the initial visit, the mean baseline FCPT was 441.03±128.68 μm in the eyes with DRIL and 337.26±99.31 μm in the eyes without DRIL (P=0.001). No significant differences were observed in MT (P=0.357). The mean size of transverse and vertical diameters of DRIL was 684.07±267.51 and 267.07±104.61 μm at baseline, respectively. There was significant improvement in BCVA and OCT-based parameters at 3, 6, and 12mo in all cases (P&#x003C;0.001 for each timepoint). In addition, significant differences were detected in BCVA and OCT parameters between eyes with and without DRIL at each time point (P&#x003C;0.01 for each timepoint). A greater DRIL range at baseline was associated with a worse baseline BCVA (transverse diameter of DRIL: r=0.875, P&#x003C;0.001; vertical diameter of DRIL: r=0.622, P&#x003C;0.001). The transverse diameter of baseline DRIL was found to be significantly correlated with the final BCVA (P=0.003). CONCLUSION: The improvement in BCVA is associated with DRIL in patients with UME. DRIL is an easy-to-determine and robust imaging biomarker that could help predict BCVA prognosis in eyes with UME.

Human gaze is precisely aligned with the foveolar cone topography of both eyes

The small physical depression of the human retina, termed fovea, is the functional center of human vision, providing an acute sense of visual space and color, but it is yet unclear if the exact arrangement of the few thousand photoreceptors at the foveal center is relevant for visual behavior. By employing adaptive optics in vivo imaging and micro-stimulation, we created complete topographical maps of the foveolar cone mosaics in both eyes of 20 healthy participants while simultaneously recording the exact retinal location of a fixated visual object in a psychophysical experiment. We found that the locus of fixation was systematically shifted away from the topographical centers towards a naso-superior quadrant of the foveolea in both eyes, thereby creating an enlarged binocular area of visual space sampled by high density cones. This demonstrates a finely tuned link between the development of the cellular arrangement of the photoreceptors of the foveola and visual behavior.

Degenerative lamellar macular holes: tractional development and morphological alterations

Purpose The development of degenerative lamellar macular holes (DLH) is largely unclear. This study was aimed at documenting with spectral-domain optical coherence tomography the tractional development and morphological alterations of DLH. Methods A retrospective case series of 44 eyes of 44 patients is described. Results The development of DLH is preceded for months or years by tractional deformations of the fovea due to the action of contractile epiretinal membranes (ERM) and/or the partially detached posterior hyaloid, or by cystoid macular edema (CME). DLH may develop after a tractional stretching and thickening of the foveal center, from a foveal pseudocyst, after a detachment of the foveola from the retinal pigment epithelium, a disruption of the foveal structure due to CME, and after surgical treatment of tractional lamellar or full-thickness macular holes (FTMH). The foveal configuration of a DLH can be spontaneously reestablished after short transient episodes of CME and a small FTMH. A DLH can evolve to a FTMH by traction of an ERM. Surgical treatment of a DLH may result in an irregular regeneration of the foveal center without photoreceptors. Conclusions Tractional forces play an important role in the development of DLH and in the further evolution to FTMH. It is suggested that a DLH is the result of a retinal wound repair process after a tractional disruption of the Müller cell cone and a degeneration of Henle fibers, to prevent a further increase in the degenerative cavitations.