Biomedical Engineering and Bioengineering Commons^™

Multimodal Imaging Of Photoreceptor Structure In Choroideremia, Lynn W. Sun, Ryan D. Johnson, Vesper Williams, Phyllis Summerfelt, Alfredo Dubra, David V. Weinberg, Kimberly E. Stepien, Gerald A. Fishman, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Purpose

Choroideremia is a progressive X-linked recessive dystrophy, characterized by degeneration of the retinal pigment epithelium (RPE), choroid, choriocapillaris, and photoreceptors. We examined photoreceptor structure in a series of subjects with choroideremia with particular attention to areas bordering atrophic lesions.

Methods

Twelve males with clinically-diagnosed choroideremia and confirmed hemizygous mutations in the CHM gene were examined. High-resolution images of the retina were obtained using spectral domain optical coherence tomography (SD-OCT) and both confocal and non-confocal split-detector adaptive optics scanning light ophthalmoscope (AOSLO) techniques.

Results

Eleven CHM gene mutations (3 novel) were identified; three subjects had the same mutation and one …

Photoreceptor Inner Segment Morphology In Best Vitelliform Macular Dystrophy, Drew Scoles, Yusufu N. Sulai, Robert F. Cooper, Brian P. Higgins, Ryan D. Johnson, Joseph Carroll, Alfredo Dubra, Kimberly E. Stepien

Biomedical Engineering Faculty Research and Publications

PURPOSE

To characterize outer retina structure in best vitelliform macular dystrophy (BVMD) and to determine the effect of macular lesions on overlying and adjacent photoreceptors.

METHODS

Five individuals with BVMD were followed prospectively with spectral domain optical coherence tomography and confocal and nonconfocal split-detector adaptive optics scanning light ophthalmoscopy (AOSLO). The AOSLO cone photoreceptor mosaic images were obtained within and around retinal lesions. Cone density was measured inside and outside lesions. In 2 subjects, densities were compared with published measurements acquired ∼2.5 years before. One subject was imaged 3 times over a 5-month period.

RESULTS

The AOSLO imaging demonstrated that …

Longitudinal Imaging Of Microvascular Remodelling In Proliferative Diabetic Retinopathy Using Adaptive Optics Scanning Light Ophthalmoscopy, Toco Yuen Ping Chui, Alexander Pinhas, Alexander Gan, Moataz Razeen, Nishit Shah, Eric Cheang, Chun L. Liu, Alfredo Dubra, Richard B. Rosen

Biomedical Engineering Faculty Research and Publications

Purpose

To characterise longitudinal changes in the retinal microvasculature of type 2 diabetes mellitus (T2DM) as exemplified in a patient with proliferative diabetic retinopathy (PDR) using an adaptive optics scanning light ophthalmoscope (AOSLO).

Methods

A 35-year-old T2DM patient with PDR treated with scatter pan-retinal photocoagulation at the inferior retina 1 day prior to initial AOSLO imaging along with a 24-year-old healthy control were imaged in this study. AOSLO vascular structural and perfusion maps were acquired at four visits over a 20-week period. Capillary diameter and microaneurysm area changes were measured on the AOSLO structural maps. Imaging repeatability was established using …

Assessing Photoreceptor Structure Associated With Ellipsoid Zone Disruptions Visualized With Optical Coherence Tomography, Drew Scoles, John A. Flatter, Robert F. Cooper, Christopher S. Langlo, Scott Robison, Maureen Neitz, David V. Weinberg, Mark E. Pennesi, Dennis P. Han, Alfredo Dubra, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Purpose: To compare images of photoreceptor layer disruptions obtained with optical coherence tomography (OCT) and adaptive optics scanning light ophthalmoscopy (AOSLO) in a variety of pathologic states.

Methods: Five subjects with photoreceptor ellipsoid zone disruption as per OCT and clinical diagnoses of closed-globe blunt ocular trauma (n = 2), macular telangiectasia type 2 (n = 1), blue-cone monochromacy (n = 1), or cone-rod dystrophy (n = 1) were included. Images were acquired within and around photoreceptor lesions using spectral domain OCT, confocal AOSLO, and split-detector AOSLO.

Results: There were substantial differences in the extent and appearance of the photoreceptor mosaic …

Repeatability Of In Vivo Parafoveal Cone Density And Spacing Measurements, Robert Garrioch, Christopher S. Langlo, Adam M. Dubis, Robert F. Cooper, Alfredo Dubra, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Purpose. To assess the repeatability and measurement error associated with cone density and nearest neighbor distance (NND) estimates in images of the parafoveal cone mosaic obtained with an adaptive optics scanning light ophthalmoscope (AOSLO).

Methods. Twenty-one participants with no known ocular pathology were recruited. Four retinal locations, approximately 0.65[degrees] eccentricity from the center of fixation, were imaged 10 times in randomized order with an AOSLO. Cone coordinates in each image were identified using an automated algorithm (with or without manual correction) from which cone density and NND were calculated. Owing to naturally occurring fixational instability, the 10 images recorded from …

Subclinical Photoreceptor Disruption In Response To Severe Head Trauma, Kimberly E. Stepien, Wanda M. Martinez, Adam M. Dubis, Robert F. Cooper, Alfredo Dubra, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Commotio retinae is a transient opacification of the retina due to outer retinal disruption occurring in a contrecoup fashion after blunt trauma.Histological studies in animals and humans after ocular blunt trauma have revealed that disruption occurs at the level of the photoreceptor outer segments and retinal pigment epithelium.Recent reports using optical coherence tomography (OCT) have shown detectable disruption at the level of the photoreceptor inner segment/outer segment junction and retinal pigment epithelium and that these changes may be reversible over time with restoration of normal outer retinal architecture.However, the resolution of existing OCT technology may not be sensitive enough to …