Purpose To study the correlation between glaucomatous visual field (VF) defects assessed by standard automated perimetry (SAP) and peripapillary retinal nerve fiber layer (RNFL) thinning measured by spectral domain optical coherence tomography (OCT) using a modified OCT-based peripapillary RNFL structure–function map. Patients and methods Perimetric glaucoma patients and age-matched normal control subjects were recruited from a university hospital clinic. All eyes underwent testing with the Spectralis spectral domain OCT and SAP on the same day. An OCT-based correspondence map, which correlated VF areas with peripapillary RNFL sectors was created to evaluate the relationship between glaucomatous RNFL thinning and VF ...

Purpose To assess intra / inter-observer agreement, and diagnostic capabilities of a color fundus photograph, fundus fluorescein angiography (FFA), and spectral domain optical coherence tomography (SD-OCT) in making a diagnosis of myopic choroidal neovascularization (CNV). Patients and methods Two masked observers evaluated FFA and SD-OCT images to identify the presence of myopic CNV in 80 high-myopic eyes of 57 patients. A third masked observer identified CNV on a color fundus photo. Presence of myopic CNV on a fundus photo was defined as presence of subretinal hemorrhage, thickening of the retina and / or visible membrane at the macula. Presence of myopic CNV ...

Purpose Compare wide-field Optomap imaging and optical coherence tomography (OCT) with clinical examination in diabetic retinopathy (DR). Methods Patients referred from Diabetic Eye Screening Programmes to three centres underwent dilated ophthalmoscopy and were assigned a DR grade. Wide-field colour imaging and OCT were then examined by the same clinician at that visit and a combined grade was assigned. Independent graders later reviewed the images and assigned an imaging-only grade. These three grades (clinical, combined, and imaging) were compared. The method that detected the highest grade of retinopathy, including neovascularisation, was determined. Results Two thousand and forty eyes of 1023 patients ...

Purpose Correlate OCT-derived measures of drusen and retinal pigment epithelium (RPE) atrophy areas (RAs) with demographic features in an elderly population. Patients and methods Subjects aged 50 years and older underwent Cirrus OCT scanning. Drusen area and volume were obtained from the macula within a central circle (CC) of 3   mm and a surrounding perifoveal ring (PR) of 3–5   mm, using the RPE analysis software (6.0). RA measurements were generated for the 6 × 6   mm 2 retinal area. Gender, age, smoking status, and systolic blood pressure (SBP) were considered. Results A total of 434 eyes were included. RA ...

Quantitatively determining physiological parameters at a microscopic level in the retina furthers the understanding of the molecular pathways of blinding diseases, such as diabetic retinopathy and glaucoma. An essential parameter, which has yet to be quantified noninvasively, is the retinal oxygen metabolic rate (rMRO 2 ). Quantifying rMRO 2 is challenging because two parameters, the blood flow rate and hemoglobin oxygen saturation (sO 2 ), must be measured together. We combined photoacoustic ophthalmoscopy (PAOM) with spectral domain-optical coherence tomography (SD-OCT) to tackle this challenge, in which PAOM measured the sO 2 and SD-OCT mapped the blood flow rate. We tested the integrated ...

We thank Mark Brezinski for his Correspondence ( Capabilities, limitations, and misconceptions of using OCT to assess vulnerable plaques . Nat. Rev. Cardiol. doi:10.1038/nrcardio.2014.62-c1 ) 1 on our Review ( Clinical classification of plaque morphology in coronary disease . Nat. Rev. Cardiol. 11 , 379 – 389 ; 2014 ), 2 and for his comments and clarifications. We agree that the phenomenon

Purpose The purpose of this study was to assess choroidal thickness in migraine patients during acute migraine attacks and compare them with healthy controls, using spectral domain optical coherence tomography (OCT). Patients and methods In this prospective case–control study, choroidal thicknesses of 46 migraine patients during acute migraine attacks and 46 age- and sex-matched healthy subjects were measured using a high-speed, high-resolution frequency domain-OCT device. All patients underwent a complete ophthalmic examination before the measurements. OCT measurements were taken at the same time of day (0900 hours), in order to minimize the effects of diurnal variation. Results There was ...

Serious concerns exist about the Review by Otsuka et al . (Clinical classification of plaque morphology in coronary disease. Nat. Rev. Cardiol. 11, 379–389; 2014 ), 1 some of which are discussed in this Correspondence. The concerns are predominately about the authors' understanding of the principles and application of optical coherence tomography (OCT),

Real-time optical spectrum analysis is an essential tool in observing ultrafast phenomena, such as the dynamic monitoring of spectrum evolution. However, conventional method such as optical spectrum analyzers disperse the spectrum in space and allocate it in time sequence by mechanical rotation of a grating, so are incapable of operating at high speed. A more recent method all-optically stretches the spectrum in time domain, but is limited by the allowable input condition. In view of these constraints, here we present a real-time spectrum analyzer called parametric spectro-temporal analyzer (PASTA), which is based on the time-lens focusing mechanism. It achieves a ...

The purpose is to study the diagnostic performance of optical coherence tomography (OCT) and alternative diagnostic tests for neovascular age-related macular degeneration (nAMD). Methods employed are as follows:systematic review and meta-analysis; Index test: OCT including time-domain (TD-OCT) and the most recently developed spectral domain (SD-OCT); comparator tests: visual acuity, clinical evaluation (slit lamp), Amsler chart, colour fundus photographs, infra-red reflectance, red-free images / blue reflectance, fundus autofluorescence imaging (FAF), indocyanine green angiography (ICGA), preferential hyperacuity perimetry (PHP), and microperimetry; reference standard: fundus fluorescein angiography. Databases searched included MEDLINE, MEDLINE In Process, EMBASE, Biosis, SCI, the Cochrane Library, DARE, MEDION, and ...

Purpose To compare multimodal imaging in detecting lacquer cracks in highly myopic eyes, and to correlate these findings with those of spectral-domain optical coherence tomography (SD-OCT). Methods An observational case series study. Patients with a refractive error worse than −8 diopters and lacquer cracks were recruited. The rates of detection of the lacquer cracks using multimodal imaging including near-infrared reflectance (NIR) imaging, fundus autofluorescence (FAF) imaging, and fluorescence angiography (FA) were compared. The characteristic findings of multimodal imaging were correlated with those of SD-OCT. Results NIR imaging was more sensitive (92.9 % ) in detecting lacquer cracks than either FAF (12 ...

Purpose To determine the influence of choroidal thickness (CT) and image setting on repeatability of subfoveal choroidal thickness (SFCT) manual measurement using enhanced depth imaging optical coherence tomography (EDI-OCT). Methods This retrospective study included 189 eyes from 189 adults. Two observers (A and B) measured the SFCT from 1   :   1 micron and 1   :   1 pixel images for evaluation of interobserver repeatability. Observer A performed a single additional measurement for intraobserver repeatability. Results The mean age was 45.1±11.1 years. The mean SFCT from 1   :   1 pixel and 1   :   1 micron images were 315.3±89.2 and 312 ...

Correspondence

The planarian is widely used as a model for studying tissue regeneration. In this study, we used optical coherence tomography (OCT) for the real-time, high-resolution imaging of planarian tissue regeneration. Five planaria were sliced transversely to produce 5 head and 5 tail fragments. During a 2-week regeneration period, OCT images of the planaria were acquired to analyze the signal attenuation rates, intensity ratios, and image texture features (including contrast, correlation, homogeneity, energy, and entropy) to compare the primitive and regenerated tissues. In the head and tail fragments, the signal attenuation rates of the regenerated fragments decreased from −0.2 dB ...

Powerful semiconductor sources of broadband light are useful for sensing, spectroscopy and biomedical imaging schemes such as optical coherence tomography. Although LEDs and superluminescent diodes offer broadband emission, their output powers are usually limited, which restricts applications. Now, a team from China and Scotland report…

Photothermal diffusion-wave imaging is a promising technique for the analysis of a range of media. However, traditional diffusion-wave techniques are limited by the physics of parabolic diffusion and can only produce depth-integrated planar images. Here, we report a depth-resolved photothermal imaging modality, henceforth termed truncated-correlation photothermal coherence tomography (TC-PCT). This enables three-dimensional visualization of subsurface features, which is not possible with known optical or photothermal imaging techniques. Examples include imaging of solids with intricate subsurface structures and discontinuities, such as holes in steel, burn depth profiles in tissues, and the structure of bone. It is compatible with regulations concerning maximum ...

Purpose To compare intraocular lens implantation using a motorized injector vs standard manual injector through a 2.2-mm clear corneal incision. Methods Patients underwent standard phacoemulsification using a 2.2-mm clear corneal incision. Hydrophobic acrylic aspheric intraocular lens (Acrysof SN60WF intraocular lens (IOL)) was inserted using D cartridge with manual monarch injector or autosert motorized injector. IOL safety, final incision size and wound integrity in terms of anterior and posterior wound gape, and descemet’s membrane detachment were compared between the two groups at post-operative day 1 and at 1 month using Anterior Segment Optical Coherence Tomography. Results The study ...

Optic neuritis is an inflammatory optic neuropathy that affects many patients with multiple sclerosis (MS) at some point during their disease course. Differentiation of acute episodes of MS-associated optic neuritis from other autoimmune and inflammatory optic neuropathies is vital for treatment choice and further patient management, but is not always straightforward. Over the past decade, a number of new imaging, laboratory and electrophysiological techniques have entered the clinical arena. To date, however, no consensus guidelines have been devised to specify how and when these techniques can be most rationally applied for the diagnostic work-up of patients with acute optic neuritis ...

The quarter century since the foundation of the Royal College of Ophthalmologists has coincided with immense change in the subspecialty of medical retina, which has moved from being the province of a few dedicated enthusiasts to being an integral, core part of ophthalmology in every eye department. In age-related macular degeneration, there has been a move away from targeted, destructive laser therapy, dependent on fluorescein angiography to intravitreal injection therapy of anti-growth factor agents, largely guided by optical coherence tomography. As a result of these changes, ophthalmologists have witnessed a marked improvement in visual outcomes for their patients with wet ...

Purpose To evaluate imaging findings of patients with focal choroidal excavation (FCE) in the macula using swept-source optical coherence tomography (SS-OCT) and correlate it clinically. Methods Prospective observational case series. Eleven consecutive patients (12 eyes) with FCE were described. Data on demographics and clinical presentation were collected and imaging findings (including color photography, fundus autofluorescence imaging, fluorescein angiography, indocyanine green angiography, spectral-domain optical coherence tomography, and SS-OCT) were analyzed. Results The primary diagnosis was epiretinal membrane (two eyes), choroidal neovascularization (one eye), polypoidal choroidal vasculopathy (three eyes), central serous chorioretinopathy (one eye), and dry age-related macular degeneration (two eyes). Eleven ...

Job Summary and Essential Functions: Known for its scientific and operational excellence, Regeneron is a leading science-based biopharmaceutical company that discovers, invents, develops, manufactures, and commercializes medicines for the treatment of serious medical conditions. Regeneron markets medicines for eye diseases, colorectal cancer, and a rare inflammatory condition and has product candidates in development in other areas of high unmet medical need, including hypercholesterolemia, oncology, rheumatoid arthritis, allergic asthma, and atopic dermatitis. Summary: This individual will be the key internal Ophthalmology Research scientist supporting the design and creation of viral vectors for genetic manipulation of experimental animals for the group. They ...

Optical coherence tomography (OCT) is a widely used structural imaging method. However, it has limited use in molecular imaging due to the lack of an effective contrast mechanism. Gold nanoparticles have been widely used as molecular probes for optical microcopy based on Surface Plasmon Resonance (SPR). Unfortunately, the SPR enhanced backscattering from nanoparticles is still relatively weak compared with the background signal from microscopic structures in biological tissues when imaged with OCT. Consequently, it is extremely challenging to perform OCT imaging of conventional nanoparticles in thick tissues with sensitivity comparable to that of fluorescence imaging. We have discovered and demonstrated ...

In published post-mortem pathological studies, more than two-thirds of acute coronary events are associated with the rupture of lipid-rich, voluminous, and outwardly remodelled plaques covered by attenuated and inflamed fibrous caps in the proximal part of coronary arteries. Superficial erosion of the plaques is responsible for most of the remaining events; the eroded plaques usually do not demonstrate much lipid burden, do not have thin fibrous caps, are not positively remodelled, and are not critically occlusive. Both noninvasive and invasive imaging studies have been performed to clinically define the plaque characteristics in acute coronary syndromes in an attempt to identify ...

Purpose To evaluate the effect of image compression of spectral-domain optical coherence tomography (OCT) images in the examination of eyes with exudative age-related macular degeneration (AMD). Methods Thirty eyes from 30 patients who were diagnosed with exudative AMD were included in this retrospective observational case series. The horizontal OCT scans centered at the center of the fovea were conducted using spectral-domain OCT. The images were exported to Tag Image File Format (TIFF) and 100, 75, 50, 25 and 10 % quality of Joint Photographic Experts Group (JPEG) format. OCT images were taken before and after intravitreal ranibizumab injections, and after relapse ...