1. Articles from Jay S. Duker

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    1. Microscope-Integrated Intraoperative Ultrahigh-Speed Swept-Source Optical Coherence Tomography for Widefield Retinal and Anterior Segment Imaging

      Microscope-Integrated Intraoperative Ultrahigh-Speed Swept-Source Optical Coherence Tomography for Widefield Retinal and Anterior Segment Imaging

      BACKGROUND AND OBJECTIVE: To demonstrate the feasibility of retinal and anterior segment intraoperative widefield imaging using an ultrahigh-speed, swept-source optical coherence tomography (SS-OCT) surgical microscope attachment. PATIENTS AND METHODS: A prototype post-objective SS-OCT using a 1,050-nm wavelength, 400 kHz A-scan rate, vertical cavity surface-emitting laser (VCSEL) light source was integrated to a commercial ophthalmic surgical microscope after the objective. Each widefield OCT data set was acquired in 3 seconds (1,000 × 1,000 A-scans, 12 × 12 mm 2 for retina and 10 × 10 mm 2 for anterior segment). RESULTS: Intraoperative SS-OCT was performed in 20 eyes of 20 patients ...

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    2. OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY TO DETECT MACULAR CAPILLARY ISCHEMIA IN PATIENTS WITH INNER RETINAL CHANGES AFTER RESOLVED DIABETIC MACULAR EDEMA

      OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY TO DETECT MACULAR CAPILLARY ISCHEMIA IN PATIENTS WITH INNER RETINAL CHANGES AFTER RESOLVED DIABETIC MACULAR EDEMA

      To compare foveal vascular anatomy between patients with and without disorganization of retinal inner layers (DRILs) after resolved diabetic macular edema using optical coherence tomography angiography (OCTA). Methods: Twenty-four eyes of 21 age- and sex-matched patients with resolved diabetic macular edema were included in this retrospective, cross-sectional study. All eyes were imaged with enhanced high-definition line or cross-line structural B scans and 3 × 3-mm OCTA scans. Optical coherence tomography B scans were analyzed for the presence of DRIL, and based on this, eyes were classified as either DRIL present or DRIL absent. The foveal avascular zone area on OCTA was ...

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    3. Polypoidal Choroidal Vasculopathy on Swept-Source Optical Coherence Tomography Angiography with Variable Interscan Time Analysis

      Polypoidal Choroidal Vasculopathy on Swept-Source Optical Coherence Tomography Angiography with Variable Interscan Time Analysis

      Purpose : To use a novel optical coherence tomography angiography (OCTA) algorithm termed variable interscan time analysis (VISTA) to evaluate relative blood flow speeds in polypoidal choroidal vasculopathy (PCV). Methods : Prospective cross-sectional study enrolling patients with confirmed diagnosis of PCV. OCTA of the retina and choroid was obtained with a prototype swept-source OCT system. The acquired OCT volumes were centered on the branching vascular network (BVN) and polyps as determined by indocyanine-green angiography (ICGA). The relative blood flow speeds were characterized on VISTA-OCTA. Results : Seven eyes from seven patients were evaluated. Swept-source OCTA enabled detailed enface visualization of the BVN and ...

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    4. Image Averaging, a Powerful Tool in Optical Coherence Tomography and OCT Angiography

      Image Averaging, a Powerful Tool in Optical Coherence Tomography and OCT Angiography

      In an elegantly conducted study, Uji et al 1 describe the association of averaging multiple en face images with the quality of the optical coherence tomography angiography (OCTA) images of the choroidal microvasculature. They demonstrate that the resulting vascular images approximate much more closely the structure of the choriocapillaris as visualized histopathologically. This is an interesting and potentially important advance in the ability of OCTA to image the choriocapillaris in vivo.

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    5. Diagnosing Choroidal Neovascularization in Asymptomatic Individuals Using Optical Coherence Tomography Angiography

      Diagnosing Choroidal Neovascularization in Asymptomatic Individuals Using Optical Coherence Tomography Angiography

      Optical coherence tomography angiography (OCTA) is a noninvasive, rapid imaging technique that generates angiographic images without intravenous dye injections. Cross-sectional studies have described the presence of asymptomatic choroidal neovascularization (CNV) in patients with intermediate age-related macular degeneration (AMD). This case report describes the OCT features on longitudinal follow-up of a patient who started with unilateral asymptomatic CNV and eventually developed symptomatic exudative AMD.

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    6. Visualization of changes in the foveal avascular zone in both observed and treated diabetic macular edema using optical coherence tomography angiography

      Visualization of changes in the foveal avascular zone in both observed and treated diabetic macular edema using optical coherence tomography angiography

      Background Central vision loss in diabetic retinopathy is commonly related to diabetic macular edema (DME). The objective of this study was to describe changes between consecutive visits on optical coherence tomography angiography (OCTA) of the foveal avascular zone (FAZ) in eyes with DME. Methods 20 eyes from 14 patients with DME were imaged on 2 successive clinic visits separated by at least 1 month. The mean interval between visits was 3.2 months. The only intervention used was intravitreal anti-VEGF in 11 eyes; the others were observed over time without treatment. Two different readers measured FAZ area using a pseudo-automated ...

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    7. Analysis Of AGE-RELATED Choroidal Layers Thinning In Healthy Eyes Using SWEPT-SOURCE Optical Coherence Tomography

      Analysis Of AGE-RELATED Choroidal Layers Thinning In Healthy Eyes Using SWEPT-SOURCE Optical Coherence Tomography

      Purpose: To study the changes in the choroidal layers thickness with age in a healthy population using swept-source optical coherence tomography. Methods: Retrospective data analysis of a subgroup of eyes from a previous single-center, prospective, cross-sectional, noninterventional study. One hundred and sixty-nine healthy eyes were evaluated using swept-source optical coherence tomography. Inclusion criteria were best-corrected visual acuity between 20/20 and 20/25, spherical equivalent between ±3 diopters, and no systemic or ocular diseases. Two independent investigators determined the macular horizontal choroidal thickness (CT) and the Haller's layer thickness across a 9 mm line centered at the fovea. Subjects ...

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    8. OCT Technology: Will We Be “Swept” Away?

      OCT Technology: Will We Be “Swept” Away?

      A look at the differences between spectral-domain and swept-source OCT, and the potential clinical benefits of swept-source. As is sometimes the case with technology, just when we get comfortable using a device and begin to understand its secrets, limitations and how to best put it to use in our practices, a shiny new instrument arrives and demands our attention. Though this imaging modality has been around for some time, swept-source optical coherence tomography is one such example. It captures your attention, and though you may already use a spectral-domain device, you’re left wondering if it’s the next big ...

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    9. Optical coherence tomography angiography artifacts in retinal pigment epithelial detachment

      Optical coherence tomography angiography artifacts in retinal pigment epithelial detachment

      Objective To describe optical coherence tomography angiography (OCTA) reflectance artifacts secondary to retinal pigment epithelial detachment (RPED). Design Retrospective review. Methods Four eyes from 4 subjects were included. Three presented with RPED and 1 eye was a normal control. Two eyes diagnosed with RPED and the normal eye were evaluated using en face OCTA centred at the fovea acquired using the RTVue XR Avanti (Optovue Inc). In the third eye with RPED, OCTA imaging was performed using a CIRRUS 5000 prototype modified to do OCTA imaging on a spectral domain OCT platform provided by Carl Zeiss Meditec, Inc. The segmented ...

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    10. Optical Coherence Tomography Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy

      Optical Coherence Tomography Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy

      Background: Optical coherence tomography angiography (OCTA) has demonstrated good utility in qualitative analysis of retinal and choroidal vasculature and therefore may be relevant in the diagnostic and treatment efforts surrounding nonarteritic anterior ischemic optic neuropathy (NAION). Methods: Retrospective, cross-sectional study of 10 eyes of 9 patients with a previous or new diagnosis of NAION that received imaging with OCTA between November 2015 and February 2016. Two independent readers qualitatively analyzed the retinal peripapillary capillaries (RPC) and peripapillary choriocapillaris (PCC) for flow impairment. Findings were compared with automated visual field and structural optical coherence tomography (OCT) studies. Results: Flow impairment seen ...

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    11. Choroidal Vessel Diameters in Pseudoexfoliation and Pseudoexfoliation Glaucoma Analyzed Using Spectral-Domain Optical Coherence Tomography

      Choroidal Vessel Diameters in Pseudoexfoliation and Pseudoexfoliation Glaucoma Analyzed Using Spectral-Domain Optical Coherence Tomography

      Abstract Purpose of the Study: The purpose of the study was to analyze choroidal vessel diameters in pseudoexfoliation (PXF) and pseudoexfoliation glaucoma (PXFG) using spectral-domain optical coherence tomography (SD-OCT). Materials and Methods: Fifty patients (100 eyes) with PXF and PXFG who underwent high-definition 1-line raster SD-OCT imaging at New England Eye Center, Boston, were retrospectively identified and divided into unilateral PXFG (26 patients, 52 eyes), unilateral PXF (4 patients, 8 eyes), bilateral PXFG (4 patients, 8 eyes), and bilateral PXF (16 patients, 32 eyes). Eyes with concomitant chorioretinal pathology, history of shunting/filtering for glaucoma, and significant anisometropia were excluded ...

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    12. Comparison of Optical Coherence Tomography Angiography and Fluorescein Angiography for the Identification of Retinal Vascular Changes in Eyes With Diabetic Macular Edema

      Comparison of Optical Coherence Tomography Angiography and Fluorescein Angiography for the Identification of Retinal Vascular Changes in Eyes With Diabetic Macular Edema

      BACKGROUND AND OBJECTIVE: To compare the visualization of microaneurysms (MA) and the foveal avascular zone (FAZ) area using optical coherence tomography angiography (OCTA) versus fluorescein angiography (FA) in patients with diabetic macular edema (DME). PATIENTS AND METHODS: Patients were prospectively recruited for same-day imaging on spectral-domain OCTA and FA. OCTA images were automatically segmented into superficial (sOCTA) and deep (dOCTA) capillary plexuses. The number of visible MAs and the FAZ area were compared between the two imaging modalities. RESULTS: Nineteen eyes of 10 patients were included. There was a statistically significant difference between MA counts for FA, sOCTA, and dOCTA ...

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    13. Use of Retinal Optical Coherence Tomography to Detect Congenital Zika Syndrome

      Use of Retinal Optical Coherence Tomography to Detect Congenital Zika Syndrome

      First identified in rhesus monkeys in Uganda in 1947, the Zika virus (ZIKV), a flavirus spread most commonly by the Aedes aegypti and Aedes albopictus mosquitos, 1 was not implicated in human disease until 1953, when it was recognized in Nigeria to produce a mild, febrile illness. The virus, related to the pathogens that cause yellow fever, dengue, and the West Nile virus, 1 has emerged recently as a serious health care threat resulting in widespread panic across the globe, particularly in the Pacific and the Americas. The recent outbreak began in Brazil in 2015, with over 1 million people ...

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    14. Analysis of Scleral Feeder Vessel in Myopic Choroidal Neovascularization Using Optical Coherence Tomography Angiography

      Analysis of Scleral Feeder Vessel in Myopic Choroidal Neovascularization Using Optical Coherence Tomography Angiography

      To describe the appearance of a scleral-derived feeder vessel in a highly myopic eye with secondary choroidal neovascularization (CNV) as visualized on both en face high-speed swept-source (SS) optical coherence tomography angiography (OCTA) prototype, and a commercially available spectral-domain (SD) OCTA, with the corresponding en face and cross-sectional structural OCT images. In this case report, a 60-year-old white male presented with high myopia and secondary CNV in the right eye, previously treated with anti-vascular endothelial growth factor, and was imaged on both SD-OCT and SS-OCT. The neovascular complex could be visualized on both devices. Structural en face SS-OCT images demonstrated ...

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    15. SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY REVEALS CHORIOCAPILLARIS ALTERATIONS IN EYES WITH NASCENT GEOGRAPHIC ATROPHY AND DRUSEN-ASSOCIATED GEOGRAPHIC ATROPHY

      SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY REVEALS CHORIOCAPILLARIS ALTERATIONS IN EYES WITH NASCENT GEOGRAPHIC ATROPHY AND DRUSEN-ASSOCIATED GEOGRAPHIC ATROPHY

      Purpose: To investigate choriocapillaris (CC) alteration in patients with nascent geographic atrophy (nGA) and/or drusen-associated geographic atrophy (DAGA) using swept-source optical coherence tomography angiography (OCTA). Methods: A 1,050-nm wavelength, 400 kHz A-scan rate swept-source optical coherence tomography prototype was used to perform volumetric swept-source optical coherence tomography angiography over 6 mm x 6 mm fields of view in patients with nGA and/or DAGA. The resulting optical coherence tomography (OCT) and OCTA data were analyzed using a combination of en face and cross-sectional techniques. Variable interscan time analysis (VISTA) was used to differentiate CC flow impairment from complete ...

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    16. TOWARD QUANTITATIVE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: Visualizing Blood Flow Speeds in Ocular Pathology Using Variable Interscan Time Analysis

      TOWARD QUANTITATIVE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: Visualizing Blood Flow Speeds in Ocular Pathology Using Variable Interscan Time Analysis

      Purpose: Currently available optical coherence tomography angiography systems provide information about blood flux but only limited information about blood flow speed. The authors develop a method for mapping the previously proposed variable interscan time analysis (VISTA) algorithm into a color display that encodes relative blood flow speed. Methods: Optical coherence tomography angiography was performed with a 1,050 nm, 400 kHz A-scan rate, swept source optical coherence tomography system using a 5 repeated B-scan protocol. Variable interscan time analysis was used to compute the optical coherence tomography angiography signal from B-scan pairs having 1.5 millisecond and 3.0 milliseconds ...

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    17. Optical Coherence Tomography Angiography of Chorioretinal Diseases

      Optical Coherence Tomography Angiography of Chorioretinal Diseases

      Fluorescein angiography (FA) and indocyanine green angiography (ICGA) have been the gold standard for the evaluation of retinal and choroidal vasculature in the last three decades and have revolutionized the diagnosis of retinal and choroidal vascular diseases. The advantage of these imaging modalities lies in their ability to document retinal and choroidal vasculature through the dynamic assessment of contrast transit over time in the intravascular and extravascular spaces. However, disadvantages include the absence of depth resolution, blurring of details by contrast leakage, and the inability to selectively evaluate different levels of the retinal and choroidal microvasculature. In addition, these angiographic ...

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    18. Visualizing the Choriocapillaris Under Drusen: Comparing 1050-nm Swept-Source Versus 840-nm Spectral-Domain Optical Coherence Tomography Angiography

      Visualizing the Choriocapillaris Under Drusen: Comparing 1050-nm Swept-Source Versus 840-nm Spectral-Domain Optical Coherence Tomography Angiography

      Purpose : To investigate the appearance of choriocapillaris (CC) flow under drusen by comparing long-wavelength (1050 nm) swept-source optical coherence tomography (SS-OCT) angiography with shorter-wavelength (840 nm) spectral-domain (SD) OCT angiography. Methods : Patients with drusen imaged on both devices on the same day were selected and graded. Ambiguous OCT angiography (OCTA) signal loss was defined as low OCTA signal on the en face OCTA CC image that also had low OCT signal in the corresponding area on the en face OCT CC image and OCT B-scans. Unambiguous OCTA signal loss was defined as low OCTA signal on the en face OCTA ...

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    19. ULTRAHIGH SPEED SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF RETINAL AND CHORIOCAPILLARIS ALTERATIONS IN DIABETIC PATIENTS WITH AND WITHOUT RETINOPATHY

      ULTRAHIGH SPEED SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF RETINAL AND CHORIOCAPILLARIS ALTERATIONS IN DIABETIC PATIENTS WITH AND WITHOUT RETINOPATHY

      Purpose: To investigate the utility of ultrahigh speed, swept source optical coherence tomography angiography in visualizing retinal microvascular and choriocapillaris (CC) changes in diabetic patients. Methods: The study was prospective and cross-sectional. A 1,050 nm wavelength, 400 kHz A-scan rate swept source optical coherence tomography prototype was used to perform volumetric optical coherence tomography angiography of the retinal and CC vasculatures in diabetic patients and normal subjects. Sixty-three eyes from 32 normal subjects, 9 eyes from 7 patients with proliferative diabetic retinopathy, 29 eyes from 16 patients with nonproliferative diabetic retinopathy, and 51 eyes from 28 diabetic patients without ...

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    20. Choroidal Neovascularization Analyzed on Ultrahigh-Speed Swept-Source Optical Coherence Tomography Angiography Compared to Spectral-Domain Optical Coherence Tomography Angiography

      Choroidal Neovascularization Analyzed on Ultrahigh-Speed Swept-Source Optical Coherence Tomography Angiography Compared to Spectral-Domain Optical Coherence Tomography Angiography

      Purpose To compare visualization of choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) using an ultrahigh-speed swept-source (SS) optical coherence tomography angiography (OCTA) prototype vs a spectral-domain (SD) OCTA device. Design Comparative analysis of diagnostic instruments. Methods Patients were prospectively recruited to be imaged on SD OCT and SS OCT devices on the same day. The SD OCT device employed is the RTVue Avanti (Optovue, Inc, Fremont, California, USA), which operates at ∼840 nm wavelength and 70 000 A-scans/second. The SS OCT device used is an ultrahigh-speed long-wavelength prototype that operates at ∼1050 nm wavelength and 400 000 ...

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    21. Choroidal Morphology and Vascular Analysis in Eyes With Neovascular Age-Related Macular Degeneration Using Spectral-Domain Optical Coherence Tomography

      Choroidal Morphology and Vascular Analysis in Eyes With Neovascular Age-Related Macular Degeneration Using Spectral-Domain Optical Coherence Tomography

      BACKGROUND AND OBJECTIVE: To describe morphology and vascular layer thickness of the choroid in eyes with neovascular age-related macular degeneration (AMD) using spectral-domain optical coherence tomography (SD-OCT). PATIENTS AND METHODS: Cross-sectional, retrospective analysis of 15 eyes with neovascular AMD and 11 healthy age-matched eyes that underwent single horizontal, high-definition raster line imaging using high-definition SD-OCT. Two independent graders assessed choroid morphology and measured the thickness of individual vascular layers of the choroid beneath the fovea. RESULTS: Normal concave choroidal contour was found in 13.3% of eyes with neovascular AMD and 100% of healthy eyes. The thickest point of the ...

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    22. Retinal Capillary Network and Foveal Avascular Zone in Eyes with Vein Occlusion and Fellow Eyes Analyzed With Optical Coherence Tomography Angiography

      Retinal Capillary Network and Foveal Avascular Zone in Eyes with Vein Occlusion and Fellow Eyes Analyzed With Optical Coherence Tomography Angiography

      Purpose : To evaluate the perifoveolar retinal capillary network at different depths and to quantify the foveal avascular zone (FAZ) in eyes with retinal vein occlusion (RVO) compared with their fellow eyes and healthy controls using spectral-domain optical coherence tomography angiography (SD-OCTA). Methods : We prospectively recruited 23 patients with RVO including 15 eyes with central RVO (CRVO) and 8 eyes with branch RVO (BRVO), their fellow eyes, and 8 age-matched healthy controls (8 eyes) for imaging on prototype OCTA software within RTVue-XR Avanti. The 3 × 3 mm and 6 × 6 mm en face angiograms of superficial and deep retinal capillary plexuses ...

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    23. Optical Coherence Tomography Angiography Findings in Coats' Disease

      Optical Coherence Tomography Angiography Findings in Coats' Disease

      BACKGROUND AND OBJECTIVE: To describe optical coherence tomography angiography (OCTA) findings in patients with unilateral Coats' disease. PATIENTS AND METHODS: Retrospective, observational case series of four patients with unilateral Coats' disease who underwent bilateral OCTA imaging. RESULTS: Bilateral macular OCTA findings of eight eyes are described. An abnormal foveal avascular zone (FAZ) with inner retinal vessels traversing the avascular zone in the superficial capillary plexus was visible on OCTA in the affected eye of all four patients. A similarly abnormal FAZ was noted on OCTA in the clinically normal fellow eye in two of the four patients (50%). CONCLUSION: OCTA ...

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    24. A Comparison Between Optical Coherence Tomography Angiography and Fluorescein Angiography for the Imaging of Type 1 Neovascularization

      A Comparison Between Optical Coherence Tomography Angiography and Fluorescein Angiography for the Imaging of Type 1 Neovascularization

      Purpose : To determine the sensitivity of the combination of optical coherence tomography angiography (OCTA) and structural optical coherence tomography (OCT) for detecting type 1 neovascularization (NV) and to determine significant factors that preclude visualization of type 1 NV using OCTA. Methods : Multicenter, retrospective cohort study of 115 eyes from 100 patients with type 1 NV. A retrospective review of fluorescein (FA), OCT, and OCTA imaging was performed on a consecutive series of eyes with type 1 NV from five institutions. Unmasked graders utilized FA and structural OCT data to determine the diagnosis of type 1 NV. Masked graders evaluated FA ...

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    1. (138 articles) Jay S. Duker
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