48 research outputs found
Multimodal imaging of a presumed embolic cilioretinal artery occlusion
PURPOSE: To describe clinical features including multimodal imaging in a rare case of presumed embolic cilioretinal artery occlusion with long-term follow-up examination. METHODS: A 61-year-old man presented after noticing an acute-onset central scotoma in the left eye during coronary arteriography. Fundus color photography, red-free imaging, near-infrared reflectance, spectral domain optical coherence tomography (OCT), fluorescein angiography, and swept-source OCT angiography were performed. RESULTS: Color and red-free fundus imaging both showed retinal whitening in the territory corresponding to a cilioretinal artery in the left eye. Consistent with an ischemic event, the near-infrared reflectance showed a hyporeflective area in the same location. Spectral domain OCT showed hyperreflectivity and generalized thickening of the inner nuclear layer, ganglion cell layer, and retinal nerve fiber layer. Seven years later, color, red-free, and near-infrared reflectance imaging appeared normal, but the spectral domain OCT showed thinning of all retinal layers in the affected area. Furthermore, swept-source OCT angiography demonstrated markedly reduced capillary flow signal in the superficial and deep capillary plexuses, corresponding to a persistent scotoma described by the patient. CONCLUSION: This case report illustrates hallmark features of a rare presumed embolic cilioretinal artery occlusion and its long-term manifestations with thorough historical and multimodal imaging data. When standard fundus imaging with color, red-free, and near-infrared reflectance appears normal years after a retinal vascular insult, OCT and OCT angiography can corroborate a patient's persistent visual deficit and provide clarity to the diagnosis
Should routine eye examinations be included in treatment bundles for patients with candidemia?
OCT and OCT Angiography Update: Clinical Application to Age-Related Macular Degeneration, Central Serous Chorioretinopathy, Macular Telangiectasia, and Diabetic Retinopathy
Similar to ultrasound adapting soundwaves to depict the inner structures and tissues, optical coherence tomography (OCT) utilizes low coherence light waves to assess characteristics in the eye. Compared to the previous gold standard diagnostic imaging fluorescein angiography, OCT is a noninvasive imaging modality that generates images of ocular tissues at a rapid speed. Two commonly used iterations of OCT include spectral-domain (SD) and swept-source (SS). Each comes with different wavelengths and tissue penetration capacities. OCT angiography (OCTA) is a functional extension of the OCT. It generates a large number of pixels to capture the tissue and underlying blood flow. This allows OCTA to measure ischemia and demarcation of the vasculature in a wide range of conditions. This review focused on the study of four commonly encountered diseases involving the retina including age-related macular degeneration (AMD), diabetic retinopathy (DR), central serous chorioretinopathy (CSC), and macular telangiectasia (MacTel). Modern imaging techniques including SD-OCT, TD-OCT, SS-OCT, and OCTA assist with understanding the disease pathogenesis and natural history of disease progression, in addition to routine diagnosis and management in the clinical setting. Finally, this review compares each imaging technique’s limitations and potential refinements
Linear and planar reflection artifacts on swept-source and spectral-domain optical coherence tomography due to hyperreflective crystalline deposits
PURPOSE: To describe novel spectral-domain (SD) and swept-source (SS) optical coherence tomography (OCT) linear and planar reflection artifacts produced by hyperreflective crystalline deposits (HCD). METHODS: Imaging from 10 eyes with HCD producing linear and planar artifacts on OCT was retrospectively analyzed. All eyes had SD-OCT (Spectralis HRA + OCT, Heidelberg Engineering, Germany) and SS-OCT angiography (PLEX Elite 9000, Carl Zeiss Meditec, Inc., Dublin, CA) acquired on the same day. The horizontal extent of planar artifacts and the corresponding HCD on B-scans was measured using a digital caliper. Artifact features from HCD in eyes with non-neovascular age-related macular degeneration (AMD) were analyzed and compared to those seen in two eyes with the "onion sign," an OCT signature previously shown to represent cholesterol crystals (CC) in the sub-retinal pigment epithelium-basal laminar space of eyes with neovascular AMD. A third eye with the "onion sign" was imaged with dense B-scan (DB)-OCTA. RESULTS: Ten eyes of ten patients (77.4 ± 8.7 years) with HCD were analyzed. On SS-OCTA, HCD produced linear artifacts of high signal intensity passing through the HCD and spanning the entire scan depth. On SD-OCT, HCD produced planar artifacts located anterior to both the retina and a hyporeflective space representing normal vitreous signal. The horizontal extent of the artifact did not differ significantly from the corresponding HCD on OCT B-scans (P = 0.62). The OCT artifacts produced by the "onion sign" appeared similar to those of HCD. The additional eye with neovascular AMD imaged with DB-OCTA was characterized by a single, vertical, linear false-flow signal crossing retinal layers. CONCLUSIONS: To the authors' knowledge, this is the first description of SD- and SS-OCT/OCTA artifacts corresponding to both HCD and the "onion sign." These artifacts are likely due to highly reflective CC previously shown on histology to correspond to both of these OCT signatures
Vitamin A deficiency and the retinal “double carrot” sign with optical coherence tomography
Background Spectral-domain optical coherence tomography (SD-OCT) and full-field electroretinography (ERG) allow retinal assessment with vitamin A deficiency (VAD). Using SD-OCT, this study aimed to characterize and follow a novel retinal abnormality in patients with VAD and intramuscular supplementation. Methods Patients with VAD were retrospectively reviewed, including SD-OCT and electroretinography. Results Three patients had VAD following bariatric or colon surgery and varying supplementation. All had nyctalopia, extinguished scotopic rod-specific function with ERG, and decreased serum vitamin A. None demonstrated surface abnormalities. All received intramuscular vitamin A with subjective resolution of symptoms. On SD-OCT, four of six eyes exhibited homogenous foveal hyperreflectivity anterior to retinal pigment epithelium-Bruch complex, reminiscent of a "double carrot", which improved following supplementation. ERG findings demonstrated improved scotopic rod-specific function in all cases; however, photopic function remained diminished in two cases. Conclusions Structural improvement of the proposed "double carrot" sign occurs soon after vitamin A supplementation. While scotopic function improves rapidly following supplementation, cone function recovers more slowly. Therefore, foveal changes such as the "double carrot" sign suggest that structural recovery of cones precedes functional recovery
Analysis of Schwalbe′s Line (Limbal Smooth Zone) by Scanning Electron Microscopy and Optical Coherence Tomography in Human Eye Bank Eyes
Purpose: Implantation of intraocular devices may become critical as they decrease in size in the future. Therefore, it is desirable to evaluate the relationship between radial location and Schwalbe′s line (smooth zone) by examining its width with scanning electron microscopy (SEM) and to correlate this with observations by optical coherence tomography (OCT).
Methods: Full corneoscleral rings were obtained from twenty-six formalin-fixed human phakic donor eyes. SEM of each eye yielded a complete montage of the smooth zone, from which the area was measured, and width was determined in each quadrant. In three different eyes, time domain anterior segment OCT (Visante, Carl Zeiss Meditec Inc., Dublin, CA, USA) and spectral domain OCT (Cirrus 4.0, Carl Zeiss Meditec Inc., Dublin, CA, USA) were used to further characterize Schwalbe′s line.
Results: The overall smooth zone width was 79±22 μm, (n=15) ranging from 43 to 115 μm. The superior quadrant (103±8 μm, n=19), demonstrated significantly wider smooth zone than both the nasal (71±5 μm, n=19, P0.05). SEM findings of the smooth zone were correlated with visualization of Schwalbe′s line by Cirrus and Visante OCT imaging.
Conclusion: The smooth zone appears widest superiorly and thinnest inferonasally, suggesting that as glaucoma surgical devices become smaller, their placement could be targeted clinically by using OCT with preference to the superior quadrant, to minimize damage to the corneal endothelium
Endogenous fungal endophthalmitis: international, multicentre, retrospective analysis of clinical outcomes following surgical and medical management, and screening
Objectives: To report the clinical outcomes of surgical management versus medical management alone in cases of endogenous fungal endophthalmitis. Additionally, we explore the role of routine ophthalmic screening. Methods: Retrospective observational multicentre study. We examined the databases of five UK centres and a tertiary centre in the United States for patients with Candida septicaemia (candidemia) and/or clinically established endogenous fungal endophthalmitis. Clinical data including visual acuity and other outcomes were reviewed and analysed with statistics. Results: A total of 404 patients were included from all centres. Forty-six eyes were diagnosed clinically as presumed EFE - of which 25 were later confirmed with positive vitreous biopsies. 18/46 received systemic medical treatment with or without intravitreal injection of antifungal agents and without a significant logMAR vision improvement from 1.15 ± 0.29 at baseline to 0.74 ± 0.21 at last follow up. The remaining 28/46 eyes received both systemic medical treatment and vitrectomy, and visual acuity improved from 1.56 ± 0.19 to 1.14 ± 0.21 after surgery (p = 0.04). At the last follow up, 18/28 eyes (64.3%) had an attached retina with no tamponade, three attached under oil and two ending up with detached retina. Silicone oil was retained in three eyes due to either patient comorbidities precluding further surgery or due to surgeon preference to ensure long-term anatomical stability. Two cases resulted in macular and/or fibrovascular scarring and one in enucleation. Out of 359 patients with candidemia, 95 (26.4%) had ophthalmological examination and only 9 (9.47% of those examined and 2.5% of the total) had endogenous fungal endophthalmitis (7 confirmed with vitreous sample cultures and 2 presumed). Conclusion: Although our findings suggest that vitrectomy may improve outcomes in select cases of EFE, the retrospective nature of our study and the potential for bias mandate cautious interpretation. Therefore, further prospective studies are necessary to shed more light with novel insights. A more targeted, case-by-case screening paradigm for patients with candidemia is advocated for optimum outcomes and efficient use of resources.</p
Multimodal imaging features and clinical relevance of subretinal lipid globules
Purpose: To describe the presence of subretinal lipid globules (SLG), analyze the multimodal imaging features inherent in their optical properties and provide a means to distinguish them from other retinal structures and clinical signs.
Design: Retrospective cohort study.
Methods: The clinical data and multimodal imaging features of 39 patients (49 eyes) showing SLG were evaluated. Patients underwent color fundus photography, near-infrared reflectance (NIR), spectral-domain (SD) and swept-source (SS) optical coherence tomography (OCT) and OCT angiography. In vitro phantom models were used to model OCT optical properties of water, mineral oil, and intralipid droplets and to investigate the optical mechanisms producing hypertransmission tails beneath SLG.
Results: The SLG were not visible in color fundus photographs or NIR images. With both SD- and SS-OCT B-scans, SLG appeared as 31-157 micron round hyporeflective structures demonstrating a characteristic hypertransmission tail previously described with lipid globules found in the choroid and in neovascular membranes. Similarly, with en face OCT, SLG appeared as small round hyporeflective structures. SLG were encountered most often in eyes with neovascular age-related macular degeneration (AMD) that had type 1 macular neovascularization (MNV) (91.8%). Of these eyes, 93.3% were receiving intravitreal anti-vascular endothelial growth factor (VEGF) therapy (median of 15 injections) with a mean follow-up of 52.6 months. The number of prior injections positively correlated with the number of SLG. The detection of MNV preceded the presence of SLG in 66.7% of cases. En face OCT showed that in many eyes (49%) SLG appeared in clusters of >10. In 38.8% of eyes, SLG were found overlying type 1 MNV and in 44.9% of eyes, often those with more numerous SLG, the SLG were located near the lesion border. In 2 eyes with AMD followed for nonexudative type 1 MNV, SLG were detected prior to the detection of other imaging signs of exudation. SLG were observed in several other exudative macular diseases. Phantom models demonstrated that the hypertransmission tail beneath SLG is related to a lensing effect produced by these hyporeflective spherical structures.
Conclusions: SLG are a newly recognized OCT feature frequently seen in eyes receiving intravitreal anti-VEGF therapy for type 1 MNV due to AMD. OCT B-scans show SLG as small, round, hyporeflective structures with a characteristic hypertransmission tail. This OCT signature is influenced by the OCT focal plane and it relates to reduced signal attenuation through oil and a lensing effect created by a higher refractive index compared to surrounding tissue
Asymmetric and Eccentric Laser Pointer Maculopathy in a Teenager
This is a Photo Essay and does not have an abstract. Please download the PDF or view the article in HTML
