En-face OCT Research Articles

Digital histology of retinal microaneurysms as provided by dense B-scan (DART) OCTA: characteristics and clinical relevance in diabetic retinopathy.

Retinal microaneurysms (MAs) are among the earliest signs of diabetic retinopathy (DR) and can be classified in several subtypes by non-invasive multimodal retinal imaging. The main aim of the present study is to characterize retinal MAs perfusion properties and their blood flow network connectivity by means of Dense Automatic-RealTime (DART) OCTA technology, checking the relationship with the multimodal retinal imaging classification and testing the clinical impact of DART. A cross-sectional, observational study setting was chosen. Multimodal retinal imaging included confocal multicolour, OCT, OCTA and DART OCTA. We classified retinal MAs accordingly with the recently proposed multimodal retinal imaging classification and we tested the role of DART OCTA for detecting retinal MAs blood flow network connectivity. We also tested the relationship with clinical parameters. We included 206 retinal MAs of 36 DR eyes. We categorized retinal MAs as red (70; 34%), mixed (106; 51%) and green (30; 15%), corresponding to precise characteristics on structural OCT and both (regular) enface and DART OCTA images. The agreement between en-face and DART OCTA techniques for detecting MAs perfusion was very high (overall ICC 0.98; p < 0.01). However, DART OCTA provided clearer visualization than enface OCTA for detecting the blood flow network connectivity of retinal MAs, especially looking at the afferent and efferent MAs capillaries. Multimodal retinal imaging classification of retinal MAs provided significant correlations with DR duration, DR stage, and macular capillary non-perfusion. DART OCTA provided several new insights on retinal MAs characteristics and their blood flow network connectivity.

Evaluating fingerprint-like patterns in the healthy Henle fiber layer using enface OCT imaging

PurposeEnface OCT may disclose a distinct “fingerprint-like' pattern within the HFL in various macular disorders. This study aims to investigate the frequency and characteristics of this pattern in healthy eyes and identify potential factors influencing its visibility. MethodsTwo, independent masked reading center graders evaluated for the presence and prominence of a fingerprint pattern in the Henle fiber layer (HFL) on enface OCT images from 33 healthy subjects (66 eyes). The prominence of the pattern was rated qualitatively using a 0–3 scale, with 3 indicating the strongest prominence. Tilt angles (relative to the normal/perpendicular at the center) of the retina were measured on horizontal and vertical B-scans, and the retinal curvature was assessed using ImageJ, in order to determine the impact of the incident light angle on the visibility and prominence of the fingerprint pattern. Inter-grader agreement using Cohen's kappa and the frequency and percentage of patterns in the entire enface image and in each quadrant were calculated and compared using the Friedman test with Dunn's post-test. A generalized estimating equation (GEE) was used to analyze the association between these metrics and fingerprint prominence. ResultsSubstantial inter-grader agreement was observed (Cohen's kappa = 0.71) for assessing the prominence of the fingerprint pattern. Over 70% of eyes exhibited some evidence of the pattern (score ≥1). Significant difference in pattern prominence across quadrants was detected (p < 0.05), with lowest prominence in the temporal quadrant (p < 0.001 for pairwise comparisons against all other quadrants). The GEE analysis to account for the extent of the effect of scan tilt angle and RPE curvature was not able to predict the prominence of the fingerprint pattern, highlighting that angle of incidence (of the scanning laser light) alone could not explain the pattern. ConclusionsThis study confirms that a fingerprint-like pattern within the HFL can also be observed in healthy eyes, challenging the notion that this finding is only manifest in the setting of disease. In addition, the lack of correlation with angle of incident light suggests that the pattern may be related to other intrinsic characteristics of the HFL.

New proposal for a multimodal imaging approach for the subclinical detection of hydroxychloroquine-induced retinal toxicity in patients with systemic lupus erythematosus

ObjectiveTo compare multimodal structural and functional diagnostic methods in patients with systemic lupus erythematosus (SLE) treated with hydroxychloroquine, to identify the best complementary approach for detecting subclinical retinal toxicity.MethodsA cross-sectional,...

Originalbeiträge (Originals). Altered microvascular density in patients with anorexia nervosa – an optical coherence tomography angiography (OCTA) pilot study

To investigate macular and peripapillary vascular density (VD) in patients with anorexia nervosa (AN) compared to healthy controls. Methods:Whole face scans of the superficial and deep macular layers and whole face and peripapillary scans of the radial peripapillary capillaries (RPC) were obtained using optical coherence tomography angiography (OCTA, AngioVueR, Optovue) in ten patients with AN and ten age-matched controls.The primary objective was to determine whether there was a difference between the vessel density (VD) in the above areas in AN and controls. P-values ≤ 0.0125 were considered statistically significant. Results: VD in the superficialmacular en-face OCTA image was significantly lower in the study group compared to the control group. Neither the deepmacula nor the radial peripapillary capillary (RPC) in the whole-face image nor the RPC-peripapillary imaging appeared to be significantly different. Conclusion: Patients with AN showed reduced VD in the superficialmacular layers compared to healthy controls, which can be discussed as a consequence of the malnutrition. OCTA could be a useful non- invasive tool to detect reduced peripheral blood supply to show vascular changes that occur before ocular symptoms.

Aneurysmal type 2 neovascularization: A new entity

To report three cases of aneurysmal type 2 neovascularization (AT2), a novel entity within the pachychoroid disease (PD) spectrum. We conducted an observational retrospective study of three patients with subretinal polyps treated with intravitreal aflibercept. We reviewed clinical and imaging data of the three patients. Best corrected visual acuity (BCVA), central macular thickness (CMT), choroidal subfoveal thickness, choroidal thickness under the polyps and the presence of a dry macula were assessed at baseline and throughout the follow-up. All of the patients showed granular hypoautofluorescence on fundus autofluorescence. Indocyanine green angiography revealed prominent hyperfluorescent branching vascular networks ending in multiple aneurysmal dilatations. Optical coherence tomography (OCT) demonstrated that the aneurysmal lesions were localized in the subretinal space. Additionally, OCT showed retinal pigment epithelial microtears, the double-layer sign and pachyvessels. En face OCT-A perfectly defined prominent telangiectatic branching vascular networks in all the patients, but only revealed polyps in two out of the three patients. Cross-sectional OCT-A demonstrated polyps as patchy circular hypoflow signals in each case. After the intravitreal treatment, BCVA remained unimproved in all of the patients, despite decreased CMT and achievement of a dry macula, as a result of the development of subretinal fibrosis. In summary, we describe a new entity within the spectrum of PD, which we have termed AT2. This novel disease is characterized by the presence of aneurysmal dilatations in the subretinal space, along with the typical features of PD, such as choroidal vascular hyperpermeability, thickening of the choroid and pachyvessels.

Pseudoaveraging for denoising of OCT angiography: a deep learning approach for image quality enhancement in healthy and diabetic eyes

BackgroundThis study aimed to develop a deep learning (DL) algorithm that enhances the quality of a single-frame enface OCTA scan to make it comparable to 4-frame averaged scan without the need for the repeated acquisitions required for averaging.MethodsEach of the healthy eyes and eyes from diabetic subjects that were prospectively enrolled in this cross-sectional study underwent four repeated 6 × 6 mm macular scans (PLEX Elite 9000 SS-OCT), and the repeated scans of each eye were co-registered to produce 4-frame averages. This prospective dataset of original (single-frame) enface scans and their corresponding averaged scans was divided into a training dataset and a validation dataset. In the training dataset, a DL algorithm (named pseudoaveraging) was trained using original scans as input and 4-frame averages as target. In the validation dataset, the pseudoaveraging algorithm was applied to single-frame scans to produce pseudoaveraged scans, and the single-frame and its corresponding averaged and pseudoaveraged scans were all qualitatively compared. In a separate retrospectively collected dataset of single-frame scans from eyes of diabetic subjects, the DL algorithm was applied, and the produced pseudoaveraged scan was qualitatively compared against its corresponding original.ResultsThis study included 39 eyes that comprised the prospective dataset (split into 5 eyes for training and 34 eyes for validating the DL algorithm), and 105 eyes that comprised the retrospective test dataset. Of the total 144 study eyes, 58% had any level of diabetic retinopathy (with and without diabetic macular edema), and the rest were from healthy eyes or eyes of diabetic subjects but without diabetic retinopathy and without macular edema. Grading results in the validation dataset showed that the pseudoaveraged enface scan ranked best in overall scan quality, background noise reduction, and visibility of microaneurysms (p < 0.05). Averaged scan ranked best for motion artifact reduction (p < 0.05). Grading results in the test dataset showed that pseudoaveraging resulted in enhanced small vessels, reduction of background noise, and motion artifact in 100%, 82%, and 98% of scans, respectively. Rates of false-positive/-negative perfusion were zero.ConclusionPseudoaveraging is a feasible DL approach to more efficiently improve enface OCTA scan quality without introducing notable image artifacts.

Effects of diabetic retinopathy on longitudinal morphological changes in AMD-associated type 1 macular neovascularization

The purpose of this study was to investigate the effect of diabetic retinopathy (DR) on longitudinal morphological changes in AMD-associated type 1 macular neovascularization using optical coherence tomography angiography (OCTA). We enrolled fifty treatment-naïve eyes with a diagnosis of exudative AMD and type 1 MNV. Twenty of 50 eyes were affected by mild DR. En face OCT angiography were examined for the MNV lesion area (mm2), the MNV flow area (mm2), the central macular thickness (CMT) and the BCVA. The OCTA acquisition was performed at the following visits: (i) before the loading phase (LP) of intravitreal injection of aflibercept (T1), and (ii) 1 month after the last intravitreal injection of loading phase comprising 3 monthly injections (T2). All morpho-functional parameters showed a significantly change at T2 compared to T1 values in both groups. Furthermore, we found a greater MNV area reduction after LP in eyes without DR (P = 0.023). With regard to the remaining parameters, no significant changes were found between two groups (P > 0.05). Our analysis revealed a less MNV area reduction after loading dose of anti-VEGF therapy in eyes affected by diabetic retinopathy.

Invited Session V: The eye as a window to systemic and neurodegenerative health: Seeking Answers through a keyhole: Harnessing the Synergy of Dynamic OCT/OCT Angiography and Adaptive Optics SLO for Retinal Assessment of Systemic Disease.

The retina is our only non-invasive access to microworld of the body's capillaries and cellular activities. Leveraging the multimodal synergy of combining dynamic methods of OCT/OCTA, with Adaptive Optics SLO, clinicians have new opportunities to better appreciate some of the complexities of human disease. Serial OCTA imaging can reveal inconsistencies in retinal perfusion not appreciated on single images and can be used to measure activity status of sickle cell microvasculopathy. This approach facilitates earlier detection and immediate assessment of disease burden. AOSLO imaging provides cellular level resolution for confirmation of these OCTA events. En face OCT reflectance images which accompany OCTA studies offer a glimpse of the macrophage-like cellular activity above the retinal surface which responds to systemically instigated vascular events below. The complementary use of AOSLO to characterize morphology of these cells provides clues to their activation status and potential role in tissue maintenance and repair. Features of clinical OCT/OCTA interpreted by AOSLO imaging have the potential to become useful clinical biomarkers of disease activity and response to treatment.

Evaluation of changes in epivascular glia before and after intravitreal dexamethasone implant: An OCT pilot study

PurposeTo detect changes in epivascular glia (EVG) in diabetic retinopathy after intravitreal dexamethasone implant using en face optical coherence tomography (enface OCT) and OCT angiography (OCTA) and to correlate improvements in functional and structural features. MethodsA total of 38 eyes of 38 patients were enroled in this prospective study. They were divided into two different study groups: the first group including 20 eyes with diabetic retinopathy type 1 complicated by macular oedema and the control group including 18 eyes from 18 healthy age-matched patients. The main outcome measures were: (i) differences at baseline in the foveal avascuar zone (FAZ) area in the study group versus control; (ii) the presence of epivascular glia in the study group versus control, (iii) differences at baseline between foveal macular thickness versus control; (iv) changes in foveal macular thickness, FAZ and epivascular glia in the study group before and after intravitreal dexamethasone implant. ResultsAt baseline FAZ area detected at OCTA was larger in the study group than in the control group, and epivascular glia was only detected in the study group. Three months after intravitreal injection of dexamethasone implant in the study group the best corrected visual acuity (BCVA) improved and central macular tickness reduced (P<0.0001). No significant differences were found in FAZ area while epivascular glia disappeared in 80% of the patients after treatment. ConclusionsGlia activation due to retinal inflammation in diabetic retinopathy (DR) can be detected on en face-OCT as epivascular glia. Intravitreal dexamethasone (DEX) implant improves both the anatomical and functional condition in the presence of these signs.

Retinal Pseudocysts in a Patient with Homonymous Hemianopia

A 33-year-old woman presented for evaluation with a history of craniopharyngioma, status postresection in childhood. Fundoscopic examination showed bilateral optic nerve pallor (A) and Humphrey Visual Field 24-2 revealed a left homonymous hemianopia (B). Spectral domain en-face OCT imaging demonstrated hemi-macular hyporeflectivity respecting the vertical mid-line (C). Structural B-scan showed retinal pseudocysts temporally in the right eye (D, top) and nasally in the left eye (D, bottom), corresponding with the left homonymous defect. Retinal pseudocysts have been described in cases of advanced optic atrophy. This is a rare case of retinal pseudocysts in the setting of homonymous visual field loss secondary to a compressive lesion. (Magnified version of Figure A-D is available online at www.aaojournal.org).

Unilateral Multifocal Focal Choroidal Excavation

Aim: To describe an unusual OCT image of FCE. Methods: This is retrospective research. 23 cases (25 eyes) of FCE were observed by SD-OCT and en-face OCT angiography (OCTA). Among all patients, there were 16 males and 7 females, and the age range is from 19 to 77 years old. Institutional review board approval and informed consent from patient was obtained. Results: Among the 23 patients assessed, unilateral multifocal focal choroidal excavation was found in 2 eyes of 2 patients. Multiple FCEs were distributed outside the fovea at varying distances from the fovea however did not involve the fovea. Unilateral multifocal FCEs can occur relatively far from the fovea and vary in size and depth. Unilateral multifocal FCEs correspond to each other on SD-OCT and en-face OCT images. Conclusion: FCE can appear simultaneously in the same fundus in a multifocal form and does not involve the fovea, which is rare in FCE.

Utility of En Face OCT for the Detection of Clinically Unsuspected Retinal Neovascularization in Patients with Diabetic Retinopathy

To assess the value of en face OCT for detecting clinically unsuspected retinal neovascularization (RNV) in patients with nonproliferative diabetic retinopathy (NPDR). A retrospective, cross-sectional study. Treatment-naïve patients clinically graded as NPDR in an ongoing prospective observational OCT angiography (OCTA) study at a tertiary care center. Each patient underwent imaging of 1 eye with a spectral-domain OCTA, generating a 17× 17-mm widefield image by montaging four 9× 9-mm scans. Two independent graders examined a combination of en face OCT, en face OCTA with a custom vitreoretinal interface slab, and cross-sectional OCTA to determine the presence of RNV. We measured the area of RNV flow within RNV lesions on en face OCTA. Detection rate of clinically occult RNV with OCT and OCTA. Of 63 enrolled eyes, 27 (43%) were clinically graded as severe NPDR, 16 (25%) as moderate NPDR, and 20 (32%) as mild NPDR. Using the combination of en face OCT, en face OCTA, and cross-sectional OCTA, the graders detected 42 RNV lesions in 12 (19%) eyes, of which 8 (67%) were graded as severe NPDR, 2 (17%) as moderate NPDR, and 2 (17%) as mild NPDR. The sensitivity of en face OCT alone for detecting eyes with RNV was similar to that of en face OCTA alone (100% vs. 92%; P= 0.32), whereas the specificity of en face OCT alone was significantly lower than that of en face OCTA alone (32% vs. 73%; P < 0.001). For detecting individual RNV lesions, the en face OCT was 100% sensitive, compared with 67% sensitivity for the en face OCTA (P < 0.001). The area of RNV lesions that manual grading with en face OCTA alone missed was significantly smaller than that of manually detectable RNV (Mean [standard deviation] RNV flow area, 0.015 [0.020] mm2 vs. 0.16 [0.36] mm2; P<0.001). The combination of en face OCT and OCTA can detect clinically occult RNV with high sensitivity. For screening these small lesions, en face OCT may be a useful imaging modality. Proprietary or commercial disclosure may be found after the references.

Artifact-Removed Quantitative Analysis of Choriocapillaris Flow Voids.

To investigate choriocapillaris flow voids (FV) with a new optical coherence tomography angiography (OCTA) image processing strategy that can eliminate artifacts caused by vitreous opacities, sub-retinal pigment epithelium fluid and deposits, and subretinal fluid (SRF) by thresholding the en-face OCT image of the outer retina. We retrospectively reviewed medical records of patients with drusen and patients with active central serous chorioretinopathy (CSC). FV number (FVn), average area (FVav), and maximum area (FVmax) and the percentage of nonperfused choriocapillaris area (PNPCA) obtained using the proposed strategy were compared with those obtained by removing only artifacts caused by the superficial capillary plexus (SCP). The SRF group included 21 eyes with active CSC and the drusen group included 29 eyes with nonexudative age-related macular degeneration. FVav, FVmax, FVn, and PNPCA obtained using the algorithm were significantly lower than those obtained by removing only SCP-related artefacts in both groups (all p<0.05). The algorithm was also able to remove 96.9% of artifacts secondary to vitreous opacities and all artifacts secondary to serous pigment epithelial detachments. Choriocapillaris nonperfusion areas on OCTA images may be overestimated in eyes with RPE abnormalities and SRF due to artifacts. These artifact areas on choriocapillaris OCTA images can be removed using thresholded images of the outer retina en-face OCT scans. Our new artifact-removal strategy is useful in the assessment of choriocapillaris FV in eyes with SRF, drusen, drusen-like deposits, and pigment epithelial detachment.

En Face OCT in Diagnosis of Persistent Subretinal Fluid and Outer Retinal Folds after Rhegmatogenous Retinal Detachment Repair

To evaluate the role of en face OCT as a diagnostic tool for the detection of persistent subretinal fluid (PSRF) and outer retinal folds (ORFs) after successful rhegmatogenous retinal detachment (RRD) repair. Observational post hoc analysis of 2 prospective surgical trials. All patients with gradable (signal strength ≥ 5 and no segmentation error) 6× 6-mm2 macular cube scans obtained using spectral-domain OCT (Carl Zeiss Meditec) between 1 and 2 months after surgery were included in this study. The scans were assessed for the presence or absence of PSRF or ORFs using en face OCT and cross-sectional B scans by 2 masked graders, with any disagreements adjudicated by a third senior masked grader. The sensitivity, specificity, and predictive accuracy (using area under the curve [AUC]) of en face OCT were compared with those of cross-sectional OCT, which is considered the gold standard. Two hundred twenty-three patients were included in this study. The Cohen kappa between the graders in the diagnosis of PSRF and ORFs using en face OCT was 0.84 and 0.86, respectively. The sensitivity of en face OCT was 100% (95% confidence interval [CI], 100%-100%) in the diagnosis of PSRF and 98.8% (95% CI, 96.5%-101.1%) in the diagnosis of ORFs. Similarly, the specificity of en face OCT was 98.7% (95% CI, 96.8%-100.5%) and 84.2% (95% CI, 78.1%-90.2%) in the diagnosis of PSRF and ORFs, respectively. The AUC was 0.99 for PSRF and 0.91 for ORFs. En face OCT has good sensitivity, specificity, and predictive accuracy (using AUC) in the diagnosis of PSRF and ORFs. En face OCT is an efficient screening tool for postoperative anatomic abnormalities, such as PSRF and ORFs, after RRD repair. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

RPE/Bruch’s Membrane Complex Micro-Rips in Central Serous Chorioretinopathy

The novel OCT images were observed in patients with CSC. CSC diagnosis was based on findings from both clinical examination and multimodal images. Although the patients had been conducted many ophthalmologic examinations, such as fundus fluorescein angiography (FFA) and indocyanine green angiography (ICG), visual field, ultrasonography, pattern visual evoked potential (PVEP), we did not assess them and evaluate the results of SD-OCT and en-face OCT examination only.

Sub-retinal pigment epithelium tubules in non-neovascular age-related macular degeneration

To describe a novel optical coherence tomography (OCT) signature resembling sub-retinal pigment epithelium (RPE) tubules (SRT) in non-neovascular age-related macular degeneration (AMD). Patients suffering from non-neovascular AMD with complete medical records and multimodal imaging were retrospectively revised in three different tertiary care centers. Multimodal imaging included color fundus photograph, spectral-domain OCT (Spectralis, Heidelberg Engineering, Germany), fundus autofluorescence, OCT angiography (RTVue XR Avanti, Optovue, Inc., Fremont, CA). A total of 7 eyes of 7 patients with drusenoid pigment epithelium detachment (PED) were consecutively analyzed. The sub-RPE tubules appeared as ovoidal structures with a hyperreflective contour and hyporeflective interior appreciable in the sub-RPE-basal lamina (BL) space on OCT B-scan. The anatomical location of the sub-RPE formations was lying above the Bruch’s membrane in 5/7 cases (71.4%) or floating in the sub-RPE-BL space in 2/7 cases (28.6%). En-face OCTA revealed a curvilinear tubulation-like structure corresponding to SRT without flow signal. Sub-RPE tubules represent a newly identified OCT signature observed in eyes with drusenoid PED. The presumed origin may include a variant of calcified structure or alternatively activated RPE cells with some residual BL or basal laminar deposits attracted to BrM for craving oxygen.

En Face OCT Detects Preretinal Abnormal Tissues Before and After Internal Limiting Membrane Peeling in Eyes with Macular Hole

To assess preretinal abnormal tissue (PAT) using en face OCT in eyes with idiopathic macular holes (MHs). Retrospective, observational study. Patients with MH who received 6× 6-mm spectral-domain-OCT scans. Preretinal abnormal tissue was detected by en face OCT images with a custom slab, defined with an anterior boundary of 6 μm anterior to the internal limiting membrane (ILM) and a posterior boundary at 3 μm posterior to the ILM. The PAT was defined as any abnormal tissues observed in en face OCT. Characteristics of preoperative and postoperative PAT. Sixty eyes with MH from 60 patients were included. Fifty-one eyes underwent preoperative analysis, and 46 eyes underwent postoperative examination. Before surgery, 48 (94%) eyes had a mean (standard deviation [SD]) PAT of 6.6 (9.8) mm2. The corresponding cross-sectional OCT showed PAT consisting of epiretinal proliferation, epivascular glia, and a preretinal hyperreflective band. Preretinal abnormal tissue was contiguous to the hole (peri-MH PAT) in 12 eyes (24%), whereas others (36 eyes, 76%) had a scattered distribution (extrafoveal PAT). The area of PAT was greater in eyes with a peri-MH PAT than in eyes with an extrafoveal PAT (P < 0.0001). Compared to the eyes with the extrafoveal PAT, the eyes with the peri-MH PAT were associated with men (P= 0.0059) and worse baseline visual acuity (VA) (P= 0.0002). In eyes with ILM peeling (42 eyes), postoperative PAT proliferation was observed from the edge of the ILM peeling toward the periphery over a 1-year follow-up. The mean (SD) area of PAT at 2 weeks after surgery was 3.4 (3.6) mm2 and increased to 12.1 (6.4) mm2 at 12 months (P < 0.0001). However, no PAT increase was observed in 4 eyes that underwent vitrectomy without ILM peeling. The postoperative PAT size was not associated with the postoperative VA. En face OCT revealed PAT in most eyes with MHs. Peri-MH PAT was associated with worse VA and was seen more frequently in male patients. Postoperative PAT proliferation may be triggered by ILM peeling, but it is not associated with worse VA.

Optic disc coloboma associated with macular retinoschisis: A case report

BACKGROUNDTo report an unusual case of bilateral optic disc coloboma associated with macular retinoschisis in the left eye.CASE SUMMARYA 37-year-old woman presented with complaints of blurred and distorted vision in her left eye for more than 1 year. Fundus examination demonstrated choroidal atrophy around the optic disc in both eyes, with a cup-to-disc ratio of 0.9. Serous retinal detachment in the macular area of the left eye. Left eye macular blood flow imaging optical coherence tomography (Angio-OCT) showed macular retinal serous cleavage. En-face OCT showed that the canal gully-like structure formed by the defect of the optic disc nerve fiber layer between the optic disc and macula, serous detachment area was connected with the enlarged optic disc coloboma through the canal gully-like structure, and the fluid leaked from the enlarged and thinned optic disc coloboma into the retinal layer of the macular area. Patients with optic disc abnormalities and macular degeneration must be monitored appropriately. During the follow-up period, the use of optic disc stereography and 3D-OCT, en-face, and Angio-OCT imaging can clarify the correlation between macular retinoschisis and optic disc coloboma.CONCLUSIONMacular retinoschisis may be owing to the combined force of disc edge loss, enlarged optic disc coloboma, the canal gully-like structure formed by the defect of the nerve fiber layer around the optic disc, and the traction of the posterior vitreous cortex.

Concordance of Objectively Detected Retinal Nerve Fiber Bundle Defects in En Face OCT Images with Conventional Structural and Functional Changes in Glaucoma

To assess how objectively detected defects in retinal nerve fiber bundle (RNFB) reflectance on en face OCT images relate to circumpapillary retinal nerve fiber layer thickness (cpRNFLT) and visual field defects. Cross-sectional study. Sixteen participants with early glaucoma and 29 age-matched healthy controls, of whom 22 had usable en face images for the establishment of normative levels of RNFB reflectance. All the participants underwent cpRNFLT scans, visual field examination, and wide-field OCT. En face reflectivity was assessed objectively using the Summary of Multiple Anatomically Adjusted Slabs method. En face defects were deemed concordant with cpRNFLT when they had at least 1 cpRNFLT point with P < 0.01, within ± 15° of the predicted insertion on the optic disc. Visual fields were examined using custom suprathreshold perimetry and SITA Standard 24-2. For each visual field location, the corresponding reflectance was deemed abnormal if any en face superpixel within ± 1° was abnormal. The overall, positive, and negative agreements were measured in each participant. Proportion of concordant defects between en face reflectance analysis and cpRNFLT (%) as well as overall, positive, and negative agreements between en face reflectance analysis and visual field results. Most en face abnormalities had concordant cpRNFLT defects in the mapped sector (median proportion concordant, 0.85; interquartile range, 0.74-0.95). In eyes with glaucoma, a median of 8.1% (range, 2.4%-23.7%) and 14.9% (range, 3.5%-29.1%) locations showed corresponding en face and visual field defects using 24-2 and custom perimetry, respectively. Both the perimetric strategies had moderate-to-good raw agreement with en face analysis (0.66-0.68), with stronger agreement on normal findings than on defects (0.77-0.78 and 0.4-0.44). Objectively extracted reflectance defects showed strong concordance with conventional cpRNFLT damage and good agreement with perimetry, which could be enhanced by further minimization of image artifacts.

Multimodal Imaging and En Face OCT Detection of Calcified Drusen in Eyes with Age-Related Macular Degeneration.

Purpose:En face OCT imaging was investigated as a method for the detection and monitoring of calcified drusen in eyes with nonexudative age-related macular degeneration (AMD).Design:Retrospective case series of a prospective study.Participants:Patients with nonexudative AMD.Methods:A retrospective review was performed of same-day color fundus (CF), fundus autofluorescence (FAF), near-infrared (NIR), and en face swept-source (SS) OCT images to identify eyes with nonexudative AMD and calcified drusen. The appearance and progression of these lesions were compared using the different imaging methods.Main Outcome Measures:Comparison between the presence of calcified drusen observed on CF images with the detection of these lesions on FAF, NIR, and en face SS OCT images.Results:Two hundred twenty eyes from 139 patients with nonexudative AMD were studied, with 42.7% of eyes containing calcified drusen either at baseline or during follow-up visits. On the en face SS OCT images, calcified drusen appeared as dark focal lesions referred to as choroidal hypotransmission defects (hypoTDs) that were detected in the choroid using a sub–retinal pigment epithelium (RPE) slab. The corresponding B-scans showed drusen with heterogenous internal reflectivity, hyporeflective cores, and hyperreflective caps. In most calcified drusen, choroidal hypertransmission defects (hyperTDs) were observed to develop over time around the periphery of the hypoTDs, giving them the appearance of a donut lesion on the en face SS OCT images. These donut lesions were associated with significant attenuation of the overlying retina, and the corresponding FAF images showed hypoautofluorescence at the location of these lesions. The donut lesions fulfilled the requirement for a persistent hyperTD, which is synonymous with complete RPE and outer retinal atrophy (cRORA). Six eyes displayed regression of the calcified drusen without cRORA developing. B-scans at the location of these regressed calcified drusen showed deposits along the RPE, with outer retinal thinning in the regions where the calcified lesions previously existed.Conclusions:En face OCT imaging is a useful method for the detection and monitoring of calcified drusen and can be used to document the evolution of these drusen as they form donut lesions or foci of cRORA.