En-face Optical Coherence Tomography Research Articles

Multimodal in-vivo maps as a tool to characterize retinal structural biomarkers for progression in adult-onset Stargardt disease

PurposeTo characterize retinal structural biomarkers for progression in adult-onset Stargardt disease from multimodal retinal imaging in-vivo maps.MethodsSeven adult patients (29–69 years; 3 males) with genetically-confirmed and clinically diagnosed adult-onset Stargardt disease and age-matched healthy controls were imaged with confocal and non-confocal Adaptive Optics Scanning Light Ophthalmoscopy (AOSLO), optical coherence tomography (OCT), fundus infrared (FIR), short wavelength-autofluorescence (FAF) and color fundus photography (CFP). Images from each modality were scaled for differences in lateral magnification before montages of AOSLO images were aligned with en-face FIR, FAF and OCT scans to explore changes in retinal structure across imaging modalities. Photoreceptors, retinal pigment epithelium (RPE) cells, flecks, and other retinal alterations in macular regions were identified, delineated, and correlated across imaging modalities. Retinal layer-thicknesses were extracted from segmented OCT images in areas of normal appearance on clinical imaging and intact outer retinal structure on OCT. Eccentricity dependency in cell density was compared with retinal thickness and outer retinal layer thickness, evaluated across patients, and compared with data from healthy controls.ResultsIn patients with Stargardt disease, alterations in retinal structure were visible in different image modalities depending on layer location and structural properties. The patients had highly variable foveal structure, associated with equally variable visual acuity (-0.02 to 0.98 logMAR). Cone and rod photoreceptors, as well as RPE-like structures in some areas, could be quantified on non-confocal split-detection AOSLO images. RPE cells were also visible on dark field AOSLO images close to the foveal center. Hypo-reflective gaps of non-waveguiding cones (dark cones) were seen on confocal AOSLO in regions with clinically normal CFP, FIR, FAF and OCT appearance and an intact cone inner segment mosaic in three patients.ConclusionDark cones were identified as a possible first sign of retinal disease progression in adult-onset Stargardt disease as these are observed in retinal locations with otherwise normal appearance and outer retinal thickness. This corroborates a previous report where dark cones were proposed as a first sign of progression in childhood-onset Stargardt disease. This also supports the hypothesis that, in Stargardt disease, photoreceptor degeneration occurs before RPE cell death.

Defining the structure–function relationship of specific lesions in early and advanced age-related macular degeneration

The objective of this study is to define structure–function relationships of pathological lesions related to age-related macular degeneration (AMD) using microperimetry and multimodal retinal imaging. We conducted a cross-sectional study of 87 patients with AMD (30 eyes with early and intermediate AMD and 110 eyes with advanced AMD), compared to 33 normal controls (66 eyes) recruited from a single tertiary center. All participants had enface and cross-sectional optical coherence tomography (Heidelberg HRA-2), OCT angiography, color and infra-red (IR) fundus and microperimetry (MP) (Nidek MP-3) performed. Multimodal images were graded for specific AMD pathological lesions. A custom marking tool was used to demarcate lesion boundaries on corresponding enface IR images, and subsequently superimposed onto MP color fundus photographs with retinal sensitivity points (RSP). The resulting overlay was used to correlate pathological structural changes to zonal functional changes. Mean age of patients with early/intermediate AMD, advanced AMD and controls were 73(SD = 8.2), 70.8(SD = 8), and 65.4(SD = 7.7) years respectively. Mean retinal sensitivity (MRS) of both early/intermediate (23.1 dB; SD = 5.5) and advanced AMD (18.1 dB; SD = 7.8) eyes were significantly worse than controls (27.8 dB, SD = 4.3) (p < 0.01). Advanced AMD eyes had significantly more unstable fixation (70%; SD = 63.6), larger mean fixation area (3.9 mm2; SD = 3.0), and focal fixation point further away from the fovea (0.7 mm; SD = 0.8), than controls (29%; SD = 43.9; 2.6 mm2; SD = 1.9; 0.4 mm; SD = 0.3) (p ≤ 0.01). Notably, 22 fellow eyes of AMD eyes (25.7 dB; SD = 3.0), with no AMD lesions, still had lower MRS than controls (p = 0.04). For specific AMD-related lesions, end-stage changes such as fibrosis (5.5 dB, SD = 5.4 dB) and atrophy (6.2 dB, SD = 7.0 dB) had the lowest MRS; while drusen and pigment epithelial detachment (17.7 dB, SD = 8.0 dB) had the highest MRS. Peri-lesional areas (20.2 dB, SD = 7.6 dB) and surrounding structurally normal areas (22.2 dB, SD = 6.9 dB) of the retina with no AMD lesions still had lower MRS compared to controls (27.8 dB, SD = 4.3 dB) (p < 0.01). Our detailed topographic structure–function correlation identified specific AMD pathological changes associated with a poorer visual function. This can provide an added value to the assessment of visual function to optimize treatment outcomes to existing and potentially future novel therapies.

Imaging Assessment of Peripapillary Vessel Diameters in Postmortem Eyes.

Proof of concept of ex vivo retinal vessel diameter measurements in human postmortem eyes. En face near-infrared (IR) images and optical coherence tomography (OCT) of the optic nerve head (ONH) were captured ex vivo with a Heidelberg Engineering Spectralis (Spectralis, version 7.0.4, Image Capture Module, version 1.2.4, Heidelberg Heidelberg, Germany) device, using a custom-made eye chamber holding and positioning the eyes during the image process. Thirty-two formaldehyde-fixated eyes of 16 patients were imaged. In the IR images, two independent graders measured retinal vessel diameters at the intersection of a drawn circle centered on the ONH with diameters of 2.0 mm and 3.4 mm, respectively. The anatomically corresponding measurements between both graders were statistically analyzed using a Wilcoxon signed-rank test. A total of 246 matched measurements of both graders were analyzed across all 32 imaged eyes. Statistically significant differences between the graders were found for arterioles at 2 mm from the ONH. The other measurements did not show statistically significant intergrader differences. The mean values for arteriole diameters were 72.2 µm at 2.0 mm and 61.5 µm at 3.4 mm for grader 1, and 66.4 µm at 2.0 mm and 63.2 µm at 3.4 mm for grader 2. The mean diameter for venules were 75.5 µm at 2.0 mm and 79.3 µm at 3.4 mm for grader 1, and 67.4 µm at 2 mm and 79.1 µm at 3.4 mm for grader 2. To the best of our knowledge, this is the first study to present IR image-based retinal vessel diameters in ex vivo postmortem eyes. Retinal IR/OCT imaging is possible, and measurements are reproducible in formaldehyde-fixated human eyes. Fixation artefacts result in lower image quality, and this can impose challenges in correctly detecting, classifying, and measuring retinal vessels.

Macular hole with epiretinal proliferation: diagnostic value of en-face optical coherence tomography and clinical characteristics.

To elucidate the clinical features and surgical outcomes of full-thickness macular hole (FTMH) with epiretinal proliferation (EP) diagnosed by both en-face and B-mode optical coherence tomography (OCT). This retrospective cohort study classified idiopathic FTMHs into two groups, based on B-scan and en-face OCT imaging: FTMH with EP (EP group) and without EP (non-EP group). The preoperative features, as well as postoperative outcomes up to 12months, were compared between the two groups. Among 318 eyes of idiopathic FTMH that met the inclusion criteria, 59 eyes (18.6%) were in the EP group, and others were in the non-EP group. In 9 eyes (15.3%) out of the EP group, EP was not detected in the preoperative B-mode OCT but was identified through the en-face OCT. Baseline features showed a higher male proportion (47.5% vs. 27.8%, P = 0.005) and a lower incidence of vitreofoveal traction (P < 0.001) in the EP group than in the non-EP group. The EP group showed worse visual recovery than the non-EP group (- 0.23 vs. - 0.41 logarithm of the minimum angle of the resolution at 12months, P = 0.001). The en-face OCT enhances diagnostic accuracy of EP in FTMH eyes, especially in the case with smaller extent of EP. Eyes with FTMH with EP showed a worse visual recovery than FTMH without EP.

Safety Results for Geographic Atrophy Associated with Age-Related Macular Degeneration Using Subretinal Cord Blood Platelet-Rich Plasma

PurposeTo evaluate the safety of subretinal injection of cord blood platelet-rich plasma (CB-PRP) and its possible effect in eyes affected by geographic atrophy (GA) associated with dry age-related macular degeneration (d-AMD). DesignInterventional, open-label study started in January 2021 with at 12 months of follow-up (the Si.Cord Study). This study was a single-center, nonrandomized, sequential-assigned clinical trial conducted in Rome, Italy, at Fondazione Policlinico Universitario Agostino Gemelli IRCCS (ClinicalTrials.gov_NCT04636853). Subjects, Participants, and ControlsThirteen patients (26 eyes) with bilateral d-AMD-related GA were enrolled. One eye from each patient (with more advanced GA) underwent CB-PRP treatment, and the fellow eye was considered the control. All patients participated in follow-up at 12 months. InterventionAll 13 eyes received 23-gauge (G) vitrectomy and subretinal injection of CB-PRP using a 41-G needle. Main Outcomes and MeasuresBest corrected visual acuity (BCVA) with Early Treatment Diabetic Retinopathy Study (ETDRS) letters, central macular thickness using optical coherence tomography (OCT) and atrophic area measured on en-face OCT images were assessed at baseline, 1, 3, 6 and 12 months. ResultsThe BCVA in the treated group was 34.46 ± 20.8 ETDRS at baseline; 40.84 ± 20.52 at 1 month; 40.07 ± 20.34 at 3 months; 39.38 ± 19.84 at 6 months and 35.84 ± 18.38 at 12 months. In the untreated group, the BCVA was 53 ± 21.1 ETDRS letters at baseline; 51.54 ± 20.99 at 1 month; 46.62 ± 19.47 at 3 months; 46.85 ± 18.58 at 6 months and 43.92 ± 17.97 at 12 months (two-way ANOVA: interaction of treatment by eye or time, p= -0.084). Central macular thickness (CMT) did not show a significant inter-eye difference at 12 months (p=0.97). The atrophic geographic areas tended to increase in both treated and fellow eyes at 12 months (p<0.0001). No inflammatory reaction, endophthalmitis, retinal detachment, uveitis, or other complications due to the subretinal injection of CB-PRP were observed during the follow-up. ConclusionsSubretinal injection of CB-PRP could be safely used for d-AMD in its GA form. Despite its safety, a larger cohort of patients, and probably a new way of administration, will be needed in order to understand whether the CB-PRP could have a role in the GA treatment.

Evaluation of epiretinal membrane formation after scleral buckling for treating rhegmatogenous retinal detachment: En face optical coherence tomography image-based study.

To assess epiretinal membrane (ERM) formation, severity, and the associated risk factors after scleral buckling using en face optical coherence tomography (OCT) images. Medical records of 61 consecutive patients (66 eyes) with rhegmatogenous retinal detachment who underwent scleral buckling were retrospectively reviewed. Posterior vitreous detachment (PVD) was determined based on B-scan OCT images. En face OCT images were used to visualize the ERM and retinal folds. ERM formation was identified by comparing en face images pre- and post-surgery. The maximum depth of the retinal folds (MDRF) was measured using en face imaging to objectively assess traction strength. ERM formation occurred in 15 (22.7%) eyes at the final visit; the foveal pit was preserved in all cases. Parafoveal retinal folds were present in 5 (7.6%) eyes, with a mean MDRF of 21.8 ± 12.6µm. No significant difference was observed in best-corrected visual acuity (logarithm of the minimal angle of resolution) between the ERM formation (-0.019 ± 0.128) and non-ERM formation (-0.001 ± 0.213) groups at the final visit (P = 0.593; Mann-Whitney U test). Multivariate logistic regression analysis revealed that older age and the presence of PVD were significant risk factors for ERM formation (odds ratio 1.07, 95% confidence interval 1.01-1.14, P = 0.032; odds ratio 5.26, 95% confidence interval 1.06-26.10, P = 0.042; respectively). ERM occurred in 22.7% of cases but was mild and did not affect visual acuity. Older age and the presence of PVD are risk factors for ERM formation.

Proliferative Diabetic Retinopathy: Enface Optical Coherence Tomography of the Vitreous.

Proliferative Diabetic Retinopathy: Enface Optical Coherence Tomography of the Vitreous.

Alteration of perivascular reflectivity on optical coherence tomography of branched retinal vein obstruction

This study aimed to evaluate perivascular reflectivity in patients with branched retinal vascular obstruction (BRVO) using en-face optical coherence tomography (OCT). The study retrospectively analyzed 45 patients with recurrent BRVO, 30 with indolent BRVO, and 45 age- and sex-matched controls. Using a 3.0 × 3.0-mm deep capillary plexus slab on macular scans, OCT angiography (OCTA) and structural en-face OCT scans were divided into four quadrants. Obstructive quadrants of OCTA scans were binarized using a threshold value of mean + 2 standard deviation. The selected area of high signal strength (HSS) was applied to the structural en-face OCT scans, and the corrected mean perivascular reflectivity was calculated as the mean reflectivity on the HSS area/overall en-face OCT mean reflectivity. The same procedure was performed in the quadrants of the matched controls. Regression analysis was conducted on several factors possibly associated with corrected perivascular reflectivity. The perivascular reflectivity in the obstructive BRVO quadrant was significantly higher than in the indolent BRVO and control quadrants (P = 0.009, P = 0.003). Both univariate and multivariate regression analyses showed a significant correlation between the average number of intravitreal injections (anti-vascular endothelial growth factor or dexamethasone implant) per year and refractive errors and image binarization threshold and perivascular reflectivity (P = 0.011, 0.013, < 0.001/univariate; 0.007, 0.041, 0.005/multivariate, respectively). En-face OCT scans of the deep capillary plexus slab revealed higher perivascular reflectivity in recurrent BRVO eyes than in indolent BRVO and control eyes. The results also indicate a remarkable correlation between perivascular reflectivity and the average number of intravitreal injections, suggesting a link to recurrence rates.

Stellate Multiform Amelanotic Choroidopathy (SMACH). Clinical and Multimodal Imaging Features.

To describe the clinical and multimodal imaging features of stellate multiform amelanotic choroidopathy (SMACH; also known as serous maculopathy due to aspecific choroidopathy). Retrospective observational case series of eyes presenting with SMACH. Multimodal imaging including fundus photography, optical coherence tomography (OCT), OCT-angiography (OCTA), and indocyanine green angiography (ICGA) was analyzed. Eighteen eyes from 18 patients (mean age: 28±19 years) were included. The mean follow-up duration was 9 years. Ophthalmoscopy showed a yellowish-orange, dendriform choroidal lesion. At presentation, subretinal fluid (SRF) was seen in 10/18 cases (56%). Eight patients (44%) showed no evidence of SRF during a mean follow-up of 6 years. Cross-sectional OCT showed hyperreflective fibrous-like changes within the inner choroid with choriocapillaris flow preservation on OCTA. En face OCT showed a hyperreflective choroidal lesion with finger-like projections oriented in a stellate configuration. On ICGA, SMACH showed early and late hypofluorescence. None of the cases showed lesion growth. SMACH appears to be a unilateral choroidopathy characterized by distinctive multimodal imaging features. As SRF was absent in some cases, while a dendriform pattern was a consistent finding in all eyes, we propose renaming this entity "stellate multiform amelanotic choroidopathy", a name which retains its prior abbreviation "SMACH".

Evaluation of the changes in choroidal macular anastomoses after photodynamic therapy and in the follow-up of central serous chorioretinopathy by en face optical coherence tomography

PurposeTo evaluate the changes in the choroidal macular anastomoses after photodynamic therapy (PDT) and in the follow-up of patients with central serous chorioretinopathy (CSCR) by en face optical coherence tomography (EF-OCT). MethodsProspective study using EF-OCT images of patients with chronic CSCR treated by PDT with a minimum follow-up of 12 months and with the presence of at least two prominent anastomoses in the macula. Scans of 6 × 6 mm and 12 × 12 mm were made to assess the changes in choroidal macular anastomoses (defined as a diameter ≥150 µm) crossing the medial raphe. EF-OCT was performed before PDT and 3 days, 3 months and at the end of the follow-up after PDT. ResultsThe mean follow-up time was 23.6 ± 12.1 months. The mean number of anastomoses was 2.5 ± 1.1 in the baseline examination, being 2.3 ± 1.2 in the final examination, with no differences being observed (p = 0.110). A sub-analysis was performed to assess differences in the evolution of the anastomoses between active chronic CSCR and those in which the subretinal fluid (SRF) had been resolved, with no differences being observed in the number or caliber of anastomoses (p = 0.642 and p = 0.306). A significant decrease in the size of anastomoses was found at the 3-day (p<0.01) and 3-month (p = 0.032) visits, but not at the last follow-up visit (p = 0.156). ConclusionsThere was an early decrease in the size of the major macular choroidal anastomotic vessels after PDT treatment. Long-term studies are required to assess its evolution and its possible role in the etiopathogenesis of this disease.

EVALUATION OF PARAVASCULAR INNER RETINAL DEFECTS USING EN FACE OPTICAL COHERENCE TOMOGRAPHY.

To evaluate the prevalence and risk factors for development of paravascular inner retinal defects (PIRDs) using en face optical coherence tomography. This is a retrospective cross-sectional study. En face and cross-sectional optical coherence tomography images were reviewed (9 × 9 mm or 12 × 12 mm). Paravascular inner retinal defects were classified as either Grade 1 (i.e., paravascular inner retinal cysts) when the lesion was confined within the nerve fiber layer without any communication to the vitreous cavity or Grade 2 (i.e., paravascular lamellar hole) when the defects communicated to the vitreous. Paravascular inner retinal defect grading was correlated with presence of high myopia, stage of posterior vitreous detachment, and presence of epiretinal membrane and retinoschisis. Of 1,074 patients (2,148 eyes), PIRDs were detected in 261 eyes with a prevalence of 261 per 2,148 eyes (12.2%) and 176 per 1,074 patients (16.4%). A total of 116 eyes (44.4%) displayed Grade 2 PIRDs while 145 eyes (55.6%) were Grade 1. In the multivariate logistic regression model, the presence of partial/complete posterior vitreous detachment, retinoschisis, and epiretinal membrane was significantly correlated with PIRDs (OR = 2.78 [1.7-4.4], P < 0.001; OR = 2.93 [1.7-5], P < 0.001; and OR = 25.9 [2.8-242.5], P < 0.001, respectively). The presence of partial/complete posterior vitreous detachment and epiretinal membrane was also significantly associated with Grade 2 PIRDs versus Grade 1 PIRDs ( P = 0.03 and P < 0.001). Our results indicate that wide-field en face optical coherence tomography facilitates the identification of PIRDs over a large area of retina with a single capture. The presence of PIRDs was significantly associated with posterior vitreous detachment, epiretinal membrane, and retinoschisis, confirming the role of vitreoretinal traction in the pathogenesis of PIRDs.

Effect of red-light therapy on retinal and choroidal blood perfusion in myopic children.

To investigate the effect of repeated low-level red-light therapy (RLRLT) on retinal and choroidal blood perfusion in myopic children. Forty-seven myopic children (mean spherical equivalent refractive error [SE]: -2.31 ± 1.26 D; age range: 8.0-11.0 years) were enrolled and received RLRLT (power 2 mW, wavelength 650 nm) for 3 min twice a day, while 20 myopic children (SE: -2.75 ± 0.84 D; age range: 7.0-10.0 years) were included as a control group. All participants wore single-vision distance glasses. Refractive error, axial length (AL) and other biometric parameters were measured at baseline and during follow-up visits in the first, second and fourth weeks after initiation of treatment. Retinal thickness, subfoveal choroidal thickness (SFCT), total choroidal area (TCA), luminal area (LA), stromal area (SA) and choroidal vascularity index (CVI) were obtained using optical coherence tomography (OCT). The percentage retinal vascular density (VD%) and choriocapillaris flow voids (FV%) were measured using en-face OCT angiography. After 4 weeks of treatment, a significant increase in SFCT was observed in the RLRLT group, with an average increase of 14.5 μm (95% confidence interval [CI]: 9.6-19.5 μm), compared with a decrease of -1.7 μm (95% CI: -9.1 to 5.7 μm) in the control group (p < 0.0001). However, no significant changes in retinal thickness or VD% were observed in either group (all p > 0.05). In the OCT images from the RLRLT group, no abnormal retinal morphology related to photodamage was observed. Thehorizontal scans revealed an increase in TCA, LA and CVI over time (all p < 0.05), while SA and FV% remained unchanged (both p > 0.05). These findings indicate that RLRLT can enhance choroidal blood perfusion in myopic children, demonstrating a cumulative effect over time.

En-face optical coherence tomography hyperreflective foci of choriocapillaris in central serous chorioretinopathy

The purpose of this study is to evaluate choroidal hyperreflective foci (HRF) changes in central serous chorioretinopathy (CSC) on en-face optical coherence tomography (OCT). Retrospective analysis of 42 patients with unilateral CSC (84 eyes, including fellow eyes for controls) and 42 age- and sex-matched controls. With 4.5 × 4.5 mm macular scans, structural en-face OCT choriocapillaris (CC) slabs were used to calculate the density and number of HRF in acute CSC eyes with serous retinal detachment (SRD), resolved CSC eyes without SRD, unaffected fellow eyes, control eyes, and 1-year follow-up eyes. Based on the 2-disc diameter (3000 μm), the en-face OCT scan was divided into foveal and perifoveal lesion and analyzed to consider the impact of SRF in HRF measurement. Regression analyses were performed on the several factors with HRF number and density in the acute and resolved CSC eyes. The perifoveal density and number of CC HRF was significantly lower in the resolved CSC eyes when compared to the acute CSC eyes (P = 0.002, both), fellow eyes (P = 0.042/density, 0.028/number), and controls (P = 0.021/density, P = 0.003/number). There was no significant difference between the acute CSC eyes, fellow eyes, controls, and 1-year follow-up eyes. As subfoveal choroidal thickness decreased and choroidal vascularity (CVI) increased, the perifoveal density and number of HRF was measured higher with a significant correlation in univariate regression analysis of the acute and resolved CSC eyes (all, P < 0.05). The authors hypothesized that stromal edema induced by choroidal congestion and hyperpermeability has the greatest influence on HRF measurement, possibly affected by inflammatory cells and materials extravasation.

The big warp: Registration of disparate retinal imaging modalities and an example overlay of ultrawide-field photos and en-face OCTA images.

To develop an algorithm and scripts to combine disparate multimodal imaging modalities and show its use by overlaying en-face optical coherence tomography angiography (OCTA) images and Optos ultra-widefield (UWF) retinal images using the Fiji (ImageJ) plugin BigWarp. Optos UWF images and Heidelberg en-face OCTA images were collected from various patients as part of their routine care. En-face OCTA images were generated and ten (10) images at varying retinal depths were exported. The Fiji plugin BigWarp was used to transform the Optos UWF image onto the en-face OCTA image using matching reference points in the retinal vasculature surrounding the macula. The images were then overlayed and stacked to create a series of ten combined Optos UWF and en-face OCTA images of increasing retinal depths. The first algorithm was modified to include two scripts that automatically aligned all the en-face OCTA images. The Optos UWF image could easily be transformed to the en-face OCTA images using BigWarp with common vessel branch point landmarks in the vasculature. The resulting warped Optos image was then successfully superimposed onto the ten Optos UWF images. The scripts more easily allowed for automatic overlay of the images. Optos UWF images can be successfully superimposed onto en-face OCTA images using freely available software that has been applied to ocular use. This synthesis of multimodal imaging may increase their potential diagnostic value. Script A is publicly available at https://doi.org/10.6084/m9.figshare.16879591.v1 and Script B is available at https://doi.org/10.6084/m9.figshare.17330048.

Intervortex Venous Anastomosis in the Macula in Central Serous Chorioretinopathy Imaged by En Face Optical Coherence Tomography.

To assess the presence of macular intervortex venous anastomosis in central serous chorioretinopathy (CSCR) patients using en face optical coherence tomography (EF-OCT). A cross-sectional study where EF-OCT 6 × 6 and 12 × 12 mm macular scans of patients with unilateral chronic CSCR were evaluated for anastomosis between vortex vein systems in the central macula. The presence of prominent anastomoses was defined as a connection with a diameter ≥150 µm between the inferotemporal and superotemporal vortex vein systems which crossed the temporal raphe. Three groups were studied: CSCR eyes (with an active disease with the presence of neurosensorial detachment; n = 135), fellow unaffected eyes (n = 135), and healthy eyes as controls (n = 110). Asymmetries, abrupt termination, sausaging, bulbosities and corkscrew appearance were also assessed. In 79.2% of the CSCR eyes there were prominent anastomoses in the central macula between the inferotemporal and superotemporal vortex vein systems, being more frequent than in fellow eyes and controls (51.8% and 58.2% respectively). The number of anastomotic connections was higher in the affected eye group (2.9 ± 1.8) than in the unaffected fellow eye group (2.1 ± 1.7) and the controls (1.5 ± 1.6) (p < 0.001). Asymmetry, abrupt terminations and the corkscrew appearance of the choroidal vessels were more frequent in the affected eyes, although no differences in sausaging or bulbosities were observed. Intervortex venous anastomoses in the macula were common in CSCR, being more frequently observed in affected eyes than in fellow unaffected eyes and healthy controls. This anatomical variation could have important implications concerning the pathogenesis and classification of the disease.

En-face widefield optical coherence tomography angiography for understanding vascular networks changes in two cases of acute retinal necrosis

PurposeThe present study assesses the utility of en-face widefield optical coherence tomography angiography (OCTA) imaging for evaluating the retinal vascular network during the course of treatment in acute retinal necrosis(ARN).ObservationsOCTA images of two cases of acute retinal necrosis were analyzed. Case 1 was a 15-year-old male with visual crowding in his right eye who had best-corrected visual acuity of 16/20 and intraocular pressure of 25 mmHg in his right eye on initial evaluation. Case 2 was a 57-year-old male with visual crowding in his left eye who had best-corrected visual acuity of 20/20 in his left eye on initial examination and intraocular pressure of 19.3 mmHg.In both patients, dynamic changes could be tracked by en-face ultra-widefield OCTA imaging before and up to 1 year after surgical treatment. The images showed arteriovenous anastomosis and the nonperfused area on the surface of the retina.Conclusions and importanceEn-face widefield OCTA is useful for monitoring the structure of retinal vessels over time in acute retinal necrosis. Wide-angle OCTA is used to non-invasively examine retinal vascular dynamic changes in ARN. OCTA artifacts due to intraocular inflammation appeared, making interpretation difficult. These will remain as issues in the future. It seems difficult for a while to completely replace FA due to the problem of image clarity.

BENIGN FOVEAL DEPIGMENTATION: A MULTIMODAL IMAGING INVESTIGATION.

To describe the multimodal imaging characteristics of benign foveal depigmentation. The study was designed as prospective observational case series. Patients with benign foveal depigmentation were prospectively investigated by means of multimodal imaging, including blue-light and near-infrared fundus autofluorescence, optical coherence tomography (OCT), OCT angiography, color testing, microperimetry, and electrophysiology. The main outcome measures were vessel density and retinal pigment epithelium (RPE)/photoreceptor complex OCT reflectivity. Overall, 4 patients were identified, with bilateral and unilateral involvement in 1 case and 3 cases, respectively. Fundus autofluorescence provided variable results, showing more impairment on near-infrared fundus autofluorescence. Structural OCT revealed slight attenuation of the outer retinal bands in the area affected by benign foveal depigmentation, associated with choroidal hypertransmission, whereas enface OCT better delineated the attenuation of the reflectivity signal. The mean reflectivity intensity of RPE/photoreceptor complex was statistically significantly reduced in patients with respect to control subjects in the benign foveal depigmentation area. Optical coherence tomography angiography, color testing, microperimetry, electrooculogram, and electroretinogram findings were normal. Benign foveal depigmentation may represent a focal RPE disease. The limited alterations within the RPE band, as visualized on enface OCT and confirmed on near-infrared fundus autofluorescence, suggest an impairment in melanin production or distribution within the RPE cells.

A Comparison of Peel-Induced Maculopathy Following ILM Peeling Using a Microvacuum Pick Versus Forceps

To compare peel-induced maculopathy (PIM) using surgical forceps versus the microvacuum pick (MVP). Consecutive eyes undergoing internal limiting membrane (ILM) peeling using either the MVP or forceps were assessed. En face optical coherence tomography (OCT) images at the level of the nerve fiber layer were generated for 6-month postoperative visit. The percentage of the imaged area showing PIM was termed the PIM index. PIM severity was additionally measured using a qualitative PIM severity scale. Seventy-four consecutive eyes underwent ILM peeling with either the MVP (36/74; 49%) or forceps (38/74; 51%). At month-6 postoperatively, the mean PIM index for forceps was 7.7% vs 4.7% for the MVP (P < 0.001, R2 = 0.15). At 6 months, 26/38 eyes (68.5%) in the forceps group had either moderate or severe PIM compared to 12/36 eyes (33.3%) in the MVP group (P = 0.001). ILM peeling with the MVP resulted in lower PIM severity compared to forceps. [Ophthalmic Surg Lasers Imaging Retina 2023;54:37-42.].

Imaging vitreous cortex hyalocyte response to paracentral acute middle maculopathy (PAMM) using En Face OCT.

Vitreous cortex hyalocytes (VCH) are resident macrophage cells that provide immunosurveillance, respond to tissue injury and inflammation, and help maintain the transparency of the media. In this case report we demonstrate the use of en face optical coherence tomography (OCT) to image VCH in vivo in a patient presenting with PAMM secondary to antiphospholipid syndrome. A 38-year-old female with no known medical history presented with complaints of visual disturbances in the right eye. OCT revealed hyperreflective bands in the IPL and INL nasal to the fovea. A diagnosis of PAMM was made. Work-up revealed elevated titers of antiphospholipid antibodies. En face OCT revealed a decline in the inflammatory activation over a seven-month period as evidenced by changes in VCH distribution and morphology. Our findings suggest that monitoring changes in the distribution and morphology of VCH could have a potential clinical utility for assessing disease severity, predicting recovery, and early recognition of treatment response in various inflammatory ocular pathologies such as PAMM.

PERIVASCULAR FLOWER-BUD-LIKE LESIONS ON EN FACE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN PATIENTS WITH VITREORETINAL LYMPHOMA.

To describe perivascular flower-bud-like lesions (PFBLs) as novel characteristics of vitreoretinal lymphoma on en face optical coherence tomography (OCT) angiography. A retrospective chart review was performed on 23 consecutive patients (35 eyes), who had biopsy-proven vitreoretinal lymphoma between January 2018 and March 2021. En face OCT angiography images were analyzed before and after intervention. PFBLs were initially identified on midretinal slabs of en face OCT angiography, and were further characterized by other imaging modalities. Perivascular flower-bud-like lesions were detected in 12 eyes (34.3%) of 8 patients, of which 8 eyes had best-corrected visual acuity of 20/40 or better. In 10 of the 12 eyes, PFBLs were detected within 6 months of symptom onset. On en face OCT angiography, PFBLs presented as punctate points or confluent bands surrounding retinal vessels, with arterial and venous involvement. In 4 of the 12 eyes, arteries were mainly affected. On OCT B-scans, PFBLs commonly appeared as hyperreflective full-thickness intraretinal lesions that colocalized with subretinal pigment epithelium deposits (3 eyes, 25%) and retinal pigment epithelium irregularities (4 eyes, 33.3%). However, PFBLs could not always be identified on other imaging modalities such as fundus photographs and fundus fluorescein angiography. In all eyes with follow-up, PFBLs attenuated or resolved months after receiving chemotherapy or diagnostic vitrectomy. PFBLs are characteristic imaging findings of vitreoretinal lymphoma and may facilitate an early diagnosis of vitreoretinal lymphoma, which would in turn lead to more timely and effective treatment.