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Spectral domain optical coherence tomography and adaptive optics: imaging photoreceptor layer morphology to interpret preclinical phenotypes.

ABSTRACT: Recent years have seen the emergence of advances in imaging technology that enable in vivo evaluation of the living retina. Two of the more promising techniques, spectral domain optical coherence tomography (SD-OCT) and adaptive optics (AO) fundus imaging provide complementary views of the retinal tissue. SD-OCT devices have high axial resolution, allowing assessment of retinal lamination, while the high lateral resolution of AO allows visualization of individual cells. The potential exists to use one modality to interpret results from the other. As a proof of concept, we examined the retina of a 32 year-old male, previously diagnosed with a red-green color vision defect. Previous AO imaging revealed numerous gaps throughout his cone mosaic, indicating that the structure of a subset of cones had been compromised. Whether the affected cells had completely degenerated or were simply morphologically deviant was not clear. Here an AO fundus camera was used to re-examine the retina (~6 years after initial exam) and SD-OCT to examine retinal lamination. The static nature of the cone mosaic disruption combined with the normal lamination on SD-OCT suggests that the affected cones are likely still present.

SUBMITTER: Rha J

PROVIDER: S-EPMC3444150 | biostudies-literature | 2010

REPOSITORIES: biostudies-literature

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Spectral domain optical coherence tomography and adaptive optics: imaging photoreceptor layer morphology to interpret preclinical phenotypes.

Rha Jungtae J Dubis Adam M AM Wagner-Schuman Melissa M Tait Diane M DM Godara Pooja P Schroeder Brett B Stepien Kimberly K Carroll Joseph J

Advances in experimental medicine and biology 20100101

Recent years have seen the emergence of advances in imaging technology that enable in vivo evaluation of the living retina. Two of the more promising techniques, spectral domain optical coherence tomography (SD-OCT) and adaptive optics (AO) fundus imaging provide complementary views of the retinal tissue. SD-OCT devices have high axial resolution, allowing assessment of retinal lamination, while the high lateral resolution of AO allows visualization of individual cells. The potential exists to u ...[more]

PMID: 20238030

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Project description:PurposeTo assess the signal composition of cone photoreceptors three-dimensionally in healthy retinas using adaptive optics optical coherence tomography (AO-OCT).MethodsStudy population. Twenty healthy eyes of ten subjects (age 23 to 67). Procedures. After routine ophthalmological assessments, eyes were examined using AO-OCT. Three-dimensional volumes were acquired at 2.5° and 6.5° foveal eccentricity in four main meridians (superior, nasal, inferior, temporal). Cone densities and signal compositions were investigated in four different planes: the cone inner segment outer segment junction (IS/OS), the cone outer segment combined with the IS/OS (ISOS+), the cone outer segment tips (COST) and full en-face plane (FEF) combining signals from all mentioned cone layers. Additionally, reliability of a simple semi-automated approach for assessment of cone density was tested. Main outcome measures. Cone density of IS/OS, IS/OS+, COST and FEF. Qualitative depiction and composition of each cone layer. Inter-rater agreement of cone density measurements.ResultsMean overall cone density at all eccentricities was highest at the FEF plane (21.160/mm2), followed by COST (20.450/mm2), IS/OS+ (19.920/mm2) and IS/OS (19.530/mm2). The different meridians and eccentricities had a significant impact on cone density, with lower eccentricity resulting in higher cone densities (p≤.001), which were highest at the nasal, then temporal, then inferior and then superior meridian. Depiction of the cone mosaic differed between all 4 layers regarding signal size and packing density. Therefore, different cone layers showed evident but not complete signal overlap. Using the semi-automated technique for counting of cone signals achieved high inter-rater reliability (ICC > .99).ConclusionsIn healthy individuals qualitative and quantitative changes in cone signals are found not only in different eccentricities and meridians, but also within different photoreceptor layers. The variation between cone planes has to be considered when assessing the integrity of cone photoreceptors in healthy and diseased eyes using adaptive optics technology.

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Dataset Information

Spectral domain optical coherence tomography and adaptive optics: imaging photoreceptor layer morphology to interpret preclinical phenotypes.

Publications

Spectral domain optical coherence tomography and adaptive optics: imaging photoreceptor layer morphology to interpret preclinical phenotypes.

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