Faculty Bibliography

An 8-year-old girl with a history of type 1 diabetes was referred for an evaluation of pigment changes in the right macula. Curvilinear hypopigmented streaks were noted in the fovea, with corresponding disruption of the photoreceptor layer on spectral domain optical coherence tomography. On further questioning, a history of laser pointer play 2 years prior was elicited, with acknowledgement of direct laser pointing in the child's eye. The family was advised to remove any commercial laser devices from the home, and observation of the pathology was recommended.

PURPOSE: To use fractal dimensional analysis to investigate retinal vascular disease patterns in patients with diabetic retinopathy using spectral domain optical coherence tomography angiography. METHODS: A retrospective study was conducted which included 49 eyes from 26 control subjects and 58 eyes from 35 patients known to have diabetic retinopathy. Of the 58 eyes with known retinopathy, 31 were categorized as nonproliferative diabetic retinopathy (13 mild, 9 moderate, and 9 severe) and 27 were categorized as proliferative diabetic retinopathy. Optical coherence tomography angiography images were acquired using the RTVue XR Avanti (Optovue, Inc). Automated segmentation was obtained through both the superficial and deep capillary plexuses for each eye. Grayscale optical coherence tomography angiography images were standardized and binarized using ImageJ (National Institutes of Health). Fractal box-counting analyses were conducted using Fractalyse (TheMA). Fractal dimensions (FDs) and correlation coefficient of the superficial and deep capillary plexuses were compared between control eyes and those in various stages of diabetic retinopathy. RESULTS: The superficial and deep capillary plexuses from diabetic and control eyes were analyzed. The average FD for diabetic eyes was significantly lower than in control eyes in the superficial plexus (P = 2.4 x 10) and in the deep capillary plexus (P = 1.87 x 10 ) with a more statistically significant difference noted in the deep capillary plexus. When analyzing diabetic patients without edema noted on optical coherence tomography, the FD was significantly reduced in the superficial (P = 0.001) and deep (P = 1.49 x 10) plexuses. When analyzing diabetic patients with edema noted on optical coherence tomography, the FD was significantly reduced in the superficial (P = 2.0 x 10) and deep (P = 1.85 x 10) plexuses. CONCLUSION: The optical coherence tomography angiography FD is significantly lower in both superficial and deep capillary plexuses in eyes with all stages studied of diabetic retinopathy. The results were more often significant for the deep capillary plexus. The use of fractal analysis provides an objective criterion to assess microvascular disease burden in diabetic retinopathy.

Purpose/UNASSIGNED:To determine if inner retinal layer reflectivity in eyes with acute central retinal vein occlusion (CRVO) correlates with visual acuity at 12 months. Methods/UNASSIGNED:Macular optical coherence tomography (OCT) scans were obtained from 22 eyes of 22 patients with acute CRVO. Optical intensity ratios (OIRs), defined as the mean OCT reflectivity of the inner retinal layers normalized to the mean reflectivity of the RPE, were measured from the presenting and 1-month OCT image by both manual measurements of grayscale B-scans and custom algorithmic measurement of raw OCT volume data. OIRs were assessed for association with final visual outcome. Cohort subgroup division for analysis was determined statistically. Results/UNASSIGNED:Eyes with poorer final visual acuity (≥20/70) at 1 year were more likely to have a higher ganglion cell layer OIR than eyes with better final visual acuity (<20/70) at 1 month (manually: 0.591 to 0.735, P = 0.006, algorithmically: 0.663 to 0.799, P = 0.014). At 1 month, eyes with a poorer final visual acuity demonstrated a higher variance of OIR measurements (algorithmically: 0.087 vs. 0.160, P = 0.002) per scan than eyes with better final visual acuity. Conclusions/UNASSIGNED:In acute CRVO, ganglion cell layer changes at 1 month, including increased reflectivity and increased heterogeneity of reflectivity signal as expressed as OIR and OIR variance, were associated with a poorer visual prognosis at 1 year. Technique calibration with larger sample sizes and automated integration into OCT platforms will be necessary to determine if OIR can be a clinically useful prognostic tool.

Telemedicine services facilitate the evaluation, diagnosis, and management of the remote patient. Telemedicine has rapidly flourished in the United States and has improved access to care, outcomes, and patient satisfaction. However, the use of telemedicine in ophthalmology is currently in its infancy and has yet to gain wide acceptance. Current models of telemedicine in ophthalmology are largely performed via "store and forward" methods, but remote monitoring and interactive modalities exist. Although studies have examined the effects of telemedicine, few reports have characterized its current status. We perform a descriptive analysis of the current state of teleophthalmology in the United States. We describe the use of teleophthalmology in the hospital and outpatient settings. We also review the applications to retinopathy of prematurity, diabetic retinopathy, age-related macular degeneration, and glaucoma, as well as anticipated barriers and hurdles for the future adoption of teleophthalmology. With ongoing advances in teleophthalmology, these models may provide earlier detection and more reliable monitoring of vision-threatening diseases.

PURPOSE OF REVIEW/OBJECTIVE:This review will seek to answer if advances in ophthalmic imaging and evolution of treatment modalities have shed further light on the epidemiology, pathophysiology, diagnosis, and acute management of acute CRAO. RECENT FINDINGS/RESULTS:Imaging characteristics of acute CRAO have been further characterized with the use of fluorescein angiography, optical coherence tomography (OCT), OCT-angiography, and indocyanine-green angiography. Layer segmentation of OCT imaging has found inner retinal layer hyper-reflectivity to be a common finding in acute CRAO. Non-invasive therapies, fibrinolytic delivery, and surgical interventions for acute CRAO have been further evaluated as potential management tools. SUMMARY/CONCLUSIONS:A large body of literature reports very inconsistent treatment success with a wide variety of modalities. Currently, there is no clear evidence supporting the use of fibrinolytics in acute CRAO. Large, multicenter, randomized control trials are necessary to elucidate the role of the various acute treatment options in the management of CRAO.

Purpose: We used fractal dimensional analysis to analyze retinal vascular disease burden in eyes with diabetic retinopathy using spectral-domain optical coherence tomography angiography (OCTA). Methods: A retrospective study was performed of 13 eyes with diabetic retinopathy without diabetic macular edema and 56 control eyes. Optical coherence tomography angiography images were acquired using the RTVue XR Avanti. Automated segmentation was obtained through the superficial and deep capillary plexuses for each eye. Grayscale OCTA images were standardized and binarized using ImageJ. Fractal box-counting analyses were performed using Fractalyse. Fractal dimensions (FD) as well as software-generated vascular density analyses of the superficial and deep capillary plexuses were compared between diabetic and control eyes using 2-tailed t-tests and 1-way multivariate ANOVA (MANOVA) analyses. Results: The superficial and deep plexuses from diabetic and control eyes were analyzed. The average FD for diabetic eyes was significantly lower than control eyes for the superficial (P = 4.513 x 10-3) and deep (P = 2.653 x 10-3) capillary plexuses. In diabetic eyes, the vascular density also was significantly reduced in the superficial (P = 8.068 x 10-5) and deep (P = 3.120 x 10-6) capillary plexuses. One-way MANOVA showed a significant difference between diabetic and control eyes. Conclusions: The OCTA FD is significantly reduced in the superficial and deep capillary plexuses in eyes with diabetic retinopathy. Applying fractal analysis to OCTA imaging holds the potential to establish quantitative parameters for microvascular pathology.