Purpose To present a selected case series of different phenotypes of the normal outer plexiform layer (OPL) visualized by optical coherence tomography (OCT). Methods Five cases were selected to represent the spectrum of appearances of the OPL in this case series. Categorical descriptions of each manifestation were then developed. Additional SD-OCT scans were obtained from a normal volunteer to further support the hypothesis. Results The inner one-third of the OPL typically appears hyperreflective on OCT, while the outer two-thirds (Henle fiber layer) may have a more varied appearance. Six different phenotypes of Henle fiber layer reflectivity were noted in this ...

Purpose: To compare the measurements of drusen area from manual segmentation of color fundus photographs with those generated by an automated algorithm designed to detect elevations of the retinal pigment epithelium (RPE) on spectral domain optical coherence tomography (SDOCT) images. Methods: Fifty eyes with drusen secondary to non-exudative age-related macular degeneration (AMD) were enrolled. All eyes were imaged with the Cirrus HD-OCT instrument (Carl Zeiss Meditec, Dublin, CA) using a 200x200 A-scan raster pattern covering a 6mm X 6mm area centered on the fovea. Digital color fundus images were taken on the same day. Drusen were traced manually on the ...

Purpose: To analyze the axial distribution of intraretinal cystoid changes in patients with retinal vein occlusion (RVO), incorporating a new hypothesis about the optical coherence tomographic boundary between the outer nuclear layer and the outer plexiform layer. Methods: Data were collected from patients with RVO who underwent spectral domain coherence tomography imaging. For each image set, certified graders evaluated each retinal layer for cystoid macular edema, defined as hyporeflective intraretinal cystoid spaces. Subretinal fluid, if present, was also noted. Results: Forty-eight eyes were evaluated (24 branch RVO, 18 central RVO, 6 hemiretinal vein occlusion). Cystoid macular edema was present in ...

Purpose: The purpose of this study is to quantify the normal retinal thickness (RT) and retinal nerve fiber layer thickness (RNFLT), and to obtain cross-sectional area measurements of the main retinal artery and vein in the rabbit animal model using spectral domain optical coherence tomography (SD-OCT). Materials and methods: Fifteen eyes of 15 adult rabbits were used to obtain SD-OCT scans. RT, RNFLT and cross-sectional areas of the main retinal artery and vein were measured with a custom-made software grading tool (OCTOR) on selected B-scans at the edge of the optic nerve head and at 1, 2, 3 and 4 ...

Purpose: Changes in the choroid, in particular its thickness, are believed to be of importance in the pathophysiology of a number of retinal diseases. The purpose of this study is to adapt the graph search algorithm to semi-automatically identify the choroidal layer in spectral-domain optical coherence tomography (SD-OCT) volume scans and compare its performance to manual delineation. Methods: A graph-based multi-stage segmentation approach was used to identify the choroid, defined as the layer between the outer border of the retinal pigment epithelium (RPE) band and the choroid-sclera junction. Thirty randomly chosen macular SD-OCT (Heidelberg Spectralis) volumes were obtained from 20 ...

Purpose:To compare the sensitivity of volume scanning with optical coherence tomography (OCT), to non-mydriatic fundus photography, for the detection of retinal abnormalities in asymptomatic populations. Methods:Asymptomatic subjects without known ocular disease recruited over a six-month period .For each eye, two undilated 45º fundus images, and four undilated volume OCT image sets covering the macula and optic nerve, were obtained. Fundus photographs were evaluated for abnormalities both inside and outside the fundal area covered by OCT. OCT image sets were evaluated for internal limiting membrane irregularities, abnormal retinal thickness, hyper/hyporeflective foci, and photoreceptor/retinal pigment epithelium irregularities. Detection ...

Objective To combine “extramacular” and “enhanced depth” optical coherence tomographic (OCT) scanning protocols to facilitate enhanced characterization of patients with birdshot chorioretinopathy. Methods Spectral-domain OCT images were prospectively collected from 24 eyes of 12 patients with birdshot chorioretinopathy. The images were acquired both from the macula and from 4 peripheral locations: superior and inferior to the temporal vascular arcades, nasal to the optic disc, and temporal to the macula. All images were obtained using enhanced depth scanning protocols. Qualitative and quantitative assessments were performed and compared with those from healthy, age-matched controls. Results Generalized loss of the photoreceptor inner segment ...

In accordance with one aspect of the present invention, an optical coherence tomography instrument comprises an eyepiece for receiving at least one eye of a user is provided; a light source that outputs light that is directed through the eyepiece into the user's eye; an interferometer configured to produce optical interference using light reflected from the user's eye; an optical detector disposed so as to detect said optical interference; and electronics coupled to the detector. The electronics can be configured to perform a risk assessment analysis based on optical coherence tomography measurements obtained using the interferometer. An output ...

Carl Zeiss Meditec Press Release - Medical technology provider Carl Zeiss Meditec announced today the introduction of a new family of ZEISS OCT (Optical Coherence Tomography) products at the 2012 AAO-APAO Joint Meeting in Chicago. The new CIRRUS OCT family is comprised of two new CIRRUS™ HD-OCT products, models 5000 and 500, and two new integrated multi-modality OCT and fundus imaging systems, the CIRRUS™ photo models 800 and 600. The new OCT platforms deliver clinical and workflow solutions that span the spectrum of care and address specific workflow and practice needs. “The new CIRRUS family offers a choice of high-quality ZEISS ...

Abstract: Age-related macular degeneration (AMD) is the leading cause of severe visual loss in people aged 50 years or older in the developed world. In recent years, major advances have been made in the treatment of AMD, with the introduction of anti-angiogenic agents, offering the first hope of significant visual recovery for patients with neovascular AMD. In line with these advances, a new imaging modality—optical coherence tomography (OCT)—has emerged as an essential adjunct for the diagnosis and monitoring of patients with AMD. The ability to accurately interpret OCT images is thus a prerequisite for both retina specialists and ...

Purpose:To evaluate the effect of angle of incidence on macular thickness and volume measurements obtained by spectral-domain optical coherence tomography (SDOCT) Methods: 30 eyes from 15 healthy young subjects underwent macular cube volume scans (512 x 128 protocol) following dilation using the Cirrus SDOCT. Scans were obtained by positioning the scanning beam in the center of the dilated pupil, as well as in four eccentric positions (approximately 3 mm from the center), superior, inferior, nasal, and temporal, For creating oblique angles of incidence between the light beam and the retina. In all cases, the region scanned by the volume ...