Assessment of Vascular Change Using Swept-Source Optical Coherence Tomography Angiography: A New Theory Explains Central Visual Loss in Behcet’s Disease

Objective. To evaluate retinal vascular structural change in ocular Behcet’s using optical coherence tomography angiography (OCTA) and fluorescein angiography (FA). Methods. An analytic cross-sectional study of 37 eyes of 21 Behcet’s uveitic patients was performed. Foveal retinal thickness (FRT), perifoveal hypoperfusion areas in superficial capillary plexus (SCP), and deep capillary plexus (DCP) were measured with swept-source optical coherence tomography and OCTA. FA images were used for assessing the vascular features and correlation. Results. Twenty-one patients were enrolled (52.4% males). The average age at onset was 36.7 ± 12.93 years. The median of disease duration was 5 years (1–25). FRT was 118.1 ± 52.35 μm, which correlated with visual acuity (95% CI −60.47, −13.92). Using OCTA, the area of hypoperfusion in SCP (0.47 ± 0.17 mm2) was smaller than that in DCP (1.94 ± 3.87 mm2) (p<0.001). Superficial to deep capillary plexus nonperfusion (SCP : DCP) ratio was 0.57 ± 0.27 which had the positive coefficient correlation with visual acuity (95% CI −0.644, −0.015). Conclusions. OCTA is an alternative noninvasive method to monitor macular ischemia in Behcet. Behcet’s uveitis affects DCP more than SCP. Decreasing SCP : DCP ratio and decrease FRT correlates with poor visual acuity. Macular ischemia and DCP loss can be found early and can explain vision loss in Behcet

Combined central retinal vein, central retinal artery and cilioretinal artery occlusion with ischemic macular hole secondary to severe orbital cellulitis after black fly bite

Narumon Keorochana,1 Sritatath Vongkulsiri,2 Raveewan Choontanom31Ocular Inflammatory and Uveitis Division, Department of Ophthalmology, Phramongkutklao Hospital, Phramongkutklao College of Medicine, Bangkok, Thailand; 2Retina Division, Department of Ophthalmology, Phramongkutklao Hospital, Phramongkutklao College of Medicine, Bangkok, Thailand; 3Oculoplastic and Reconstruction Division, Department of Ophthalmology, Phramongkutklao Hospital, Phramongkutklao College of Medicine, Bangkok, ThailandBackground: Orbital cellulitis is an infection of the ocular adnexal and orbital tissues behind the orbital septum. The complications are poor prognosis. This paper is to describe some severe rare complications of orbital cellulitis.Case presentation: A case of 32-year-old female presented with acute severe progressive orbital cellulitis on the right eye after a black fly (Simuliidae spp.) bite. Orbital imaging with computed tomography and magnetic resonance imaging showed eyelid abscess with orbital abscess formation and superior ophthalmic vein thrombosis. She was promptly treated with intravenous vancomycin, piperacillin and had surgical procedures to release orbital pressure including lateral canthotomy, lateral cantholysis, and eyelid with orbital abscess drainage. Pus collection culture was positive for Staphylococcus aureus. Even though she responded well to antibiotics treatment, progression involved severe orbital inflammation with marked increased orbital pressure, and her visual acuity was such that she had no light perception. Combined central retinal vein, central retinal artery and cilioretinal artery occlusion were identified. Fundus examination showed retinal whitening at the posterior pole and a few scattered flame-shaped retinal hemorrhages. The cilioretinal artery presented with perivascular retinal whitening. A fundus fluorescein angiogram revealed cilioretinal and retinal artery filling delay and also delayed arteriovenous transit time. She also developed an ischemic macular hole after a week of treatment. We demonstrate an optical coherence tomography image showing the intact posterior hyaloid membrane that represents no traction on the macula to support the ischemic cause.Conclusion: Multiple retinal vascular occlusion and ischemic macular hole could be an early complication of severe orbital cellulitis from increased orbital pressure; therefore, close monitoring of visual acuity with IOP, and prompt treatment when indicated might reduce the risk of consequent blindness.Keywords: black fly, orbital cellulitis, central retinal vein occlusion, central retinal artery occlusion, cilioretinal artery occlusion, macular hol

Colocalization error between the scanning laser ophthalmoscope infrared reflectance and optical coherence tomography images of the heidelberg spectralis

PURPOSE: To examine the colocalization error between the infrared reflectance (IR) scanning laser ophthalmoscope (SLO) and spectral domain optical coherence tomography (SD-OCT) images of the Heidelberg Spectralis. METHODS: The IR and corresponding horizontal raster SD-OCT images were compared in 10 healthy volunteers examined with 3 Heidelberg Spectralis + OCT instruments. The center points of retinal vessels selected by random uniform sampling in scanning laser ophthalmoscope-IR images were compared with colocalizing points in corresponding SD-OCT images by two masked readers. The error of colocalization was measured in the SD-OCT image. The point positions were recorded using Cartesian coordinates measured in microns. The error of colocalization was evaluated using a fixed-effects generalized least squares regression model with location and instrument as predictor variables. RESULTS: A total of 1,617 points in the IR and SD-OCT images were analyzed, and the mean error of colocalization was 42.2 +/- 32.4 mum. The Heidelberg Spectralis instrument used was not a significant predictor of colocalization error (P = 0.15). The colocalization errors were negatively correlated with x-coordinate position (P \u3c 0.001). CONCLUSION: There is a mean colocalization error between the IR and SD-OCT images produced by the Heidelberg Spectralis that is on the scale of many features being evaluated in the fundus. The variability in these measurements means the confidence interval for the exact colocalization is much larger. Because of the magnitude and variability of the error, the colocalization feature of the Heidelberg Spectralis should be used as a rough guide, not an absolute determinant

The lack of concordance between subretinal drusenoid deposits and large choroidal blood vessels

PURPOSE: To evaluate the concordance between pseudodrusen as manifested by subretinal drusenoid deposits and large choroidal blood vessels using stereological analysis of spectral-domain optical coherence tomography (SD OCT) images. DESIGN: Retrospective, observational case series. METHODS: The SD OCT images of 31 consecutive patients with the clinical appearance of pseudodrusen from a private-referral retinal clinic were retrospectively reviewed. A grid of 19 evenly spaced vertical lines was randomly superimposed on each SD OCT image using ImageJ to perform systematic uniform random sampling. The main outcome measure was the likelihood of association between subretinal drusenoid deposits and large choroidal vessels. RESULTS: Uniform random systematic sampling of 589 samples found the proportion of geometric probes intersecting subretinal drusenoid deposits to be 0.28, large choroidal vessel 0.65, and both 0.19. This value was nearly identical to the product of the joint probabilities and was within the 95% confidence interval (0.15-0.21) of the point estimate as calculated by the binomial theorem, indicating mutual independence. The subretinal drusenoid deposits were associated with neither large choroidal vessels nor the intervals in between. CONCLUSIONS: Our results demonstrate that there is no concordance between subretinal drusenoid deposits and large choroidal vessels or the stroma in between. As a consequence, hypotheses postulating that subretinal drusenoid deposits are associated with large choroidal vessels or the choroidal stromal spaces should be abandoned. Stereological techniques are powerful methods used in image evaluation in other fields of study and appear to have utility in analyzing OCT findings of the retina and choroid

Outer retinal corrugations in age-related macular degeneration

IMPORTANCE: Optical coherence tomography (OCT) abnormalities of age-related macular degeneration (AMD) have not been fully characterized because of the complex morphology and a lack of correlative histologic studies. Expansion of our ability to interpret increasing attributes brings us closer to the goal of in vivo histologic analysis of the eye by OCT. OBJECTIVE: To describe a new outer retinal finding of AMD using spectral-domain (SD) OCT and suggest histopathologic correlates. DESIGN, SETTING, AND PARTICIPANTS: Twenty-five eyes of 16 patients with AMD with severe atrophy due to either choroidal neovascularization (CNV) or geographic atrophy (GA) and 53 donor eyes of 53 patients with late AMD were included. Imaging studies were conducted at a referral retinal practice and histopathology was done at a university research laboratory. EXPOSURES: Findings in the outer retina were evaluated in SD-OCT images in eyes with atrophy of the retinal pigment epithelium (RPE) and compared with histopathologic findings in eyes with GA or CNV that also showed loss of the RPE. MAIN OUTCOMES AND MEASURES: Spectral-domain OCT and histologic characteristics of the outer retina. RESULTS: The mean (SD) age of the 16 patients was 82.7 (7.9) years. Twenty eyes had CNV and 5 eyes had GA. The mean best-corrected visual acuity was 0.800 logMAR (interquartile range, 0.350-1.000 logMAR), a Snellen equivalent of 20/126. A curvilinear hyperreflective density was identified above the Bruch membrane line within the atrophic area in the SD-OCT images. At the internal border, the material was contiguous with the outer portion of the RPE band. Below the material was a relatively hyporeflective space. The material was thrown into folds in cases with atrophy following CNV or was seen as a sheet with numerous bumps in eyes with GA. Review of histopathologic findings of eyes with advanced GA and CNV revealed a rippled layer of basal laminar deposits in an area of RPE atrophy that was located in the same level as the curvilinear line seen in the OCT images. CONCLUSIONS AND RELEVANCE: We have described a new entity, termed outer retinal corrugations, which may correspond to histological findings of basal laminar deposits, extracellular deposits that persist in eyes with late AMD. Observation of this undulating band does not necessarily mean there is exudation or leakage; as a consequence, these patients do not need treatment based on this solitary finding

Idiopathic polypoidal choroidal vasculopathy in Thai patients with clinical and angiographic choroidal neovascularization

Chavakij Bhoomibunchoo,1 Yosanan Yospaiboon,1 Somanus Thoongsuwan,2 Duangnate Rojanaporn,3 Nawat Watanachai,4 Pichai Jirarattanasopa,5 Nattapon Wongcumchang,6 Atchara Amphornphruet,7 Sritatath Vongkulsiri,8 Eakkachai Arayangkoon9 1Department of Ophthalmology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 2Department of Ophthalmology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 3Department of Ophthalmology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, 4Department of Ophthalmology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 5Department of Ophthalmology, Faculty of Medicine, Prince of Songkla University, Songkhla, 6Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, 7Department of Ophthalmology, Rajavithi Hospital, Bangkok, 8Department of Ophthalmology, Phramongkutklao Hospital, Bangkok, 9Department of Ophthalmology, Mettapracharak Hospital, Nakhon Pathom, Thailand Objective: This study aimed to study the prevalence and characteristics of idiopathic polypoidal choroidal vasculopathy (IPCV) in Thai patients with clinical and angiographic choroidal neovascularization (CNV).Patients and methods: A consecutive case study of 140 patients presenting with CNV was conducted in nine large referral eye centers throughout Thailand. The demographic data, fundus photographs, fundus fluorescein angiography and indocyanine green angiography of the patients&nbsp;were analyzed.Results: Of 129 patients with clinical and angiographic CNV, IPCV was diagnosed in 100&nbsp;patients (77.52%), idiopathic CNVs in 16 patients (12.40%) and age-related macular degeneration (AMD) in 12 patients (9.30%). Of the 107 eyes with IPCV, 90 eyes (84.11%) had both branching venous networks (BVNs) and polypoidal lesions. Most IPCV patients (93%) had unilateral involvement and were at a younger age than AMD patients. In all, 79 eyes (73.83%) had lesions found in the macular area, 14 eyes (13.08%) in the temporal to vascular arcades, ten eyes (9.35%) in the peripapillary area and four eyes (3.74%) in both macular and peripapillary areas. The clinical manifestations of IPCV at presentation were categorized into two patterns. There were 95 eyes (88.79%) of a hemorrhagic pattern and 12 eyes (11.21%) of an exudative pattern.Conclusion: IPCV is the most common macular disease in Thai patients with CNV. Most IPCVs have both BVNs and polypoidal lesions located in the macular area and present with a hemorrhagic pattern. Keywords: idiopathic polypoidal choroidal vasculopathy, prevalence, choroidal neovascularization, age-related macular degeneratio