1. Articles from robert ritch

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    1. Parapapillary choroidal microvascular density in acute primary angle-closure and primary open-angle glaucoma: an optical coherence tomography angiography study

      Parapapillary choroidal microvascular density in acute primary angle-closure and primary open-angle glaucoma: an optical coherence tomography angiography study

      Back ground/aims To determine whether parapapillary choroidal microvasculature (PPCMv) density, measured by optical coherence tomography angiography, differed between acute primary angle-closure (APAC), primary open-angle glaucoma (POAG) and controls. Methods This is a prospective, cross-sectional, observational study. Data from 149 eyes from two academic referral centres were analysed. Automated PPCMv density was calculated in inner and outer annuli around the optic nerve region in addition to the peripapillary superficial vasculature, using customised software. A generalised estimating equation was used to compare vessel densities among groups, adjusted for confounders. Results Data from 40 eyes with APAC, 65 eyes with POAG and ...

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    2. Elucidation Of The Role Of The Lamina Cribrosa In Glaucoma Using Optical Coherence Tomography

      Elucidation Of The Role Of The Lamina Cribrosa In Glaucoma Using Optical Coherence Tomography

      Glaucoma is a chronic and progressive optic neuropathy characterized by the death of retinal ganglion cells and corresponding visual field loss. Despite the growing number of studies on the subject, the pathogenesis of the disease remains unclear. Notwithstanding, several studies have shown that the lamina cribrosa (LC) is considered an anatomic site of glaucomatous optic nerve injury, thus having a key role in the pathophysiology of glaucoma development and progression. Different morphological alterations of the LC have been described in vivo in glaucomatous eyes after the evolution of optical coherence tomography (OCT) devices. The most relevant findings were the reduction ...

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    3. Optical coherence tomography angiography in glaucoma

      Optical coherence tomography angiography in glaucoma

      Assessment of the vasculature within the optic nerve, peripapillary superficial retina, macula, and peripapillary choroid can be determined in glaucoma using optical coherence tomography angiography (OCTA). Decreased perfusion within the pre-laminar layer of the optic nerve has been correlated with glaucoma severity. The peripapillary superficial retinal vessel density allows diagnosis and detection of glaucoma progression in a manner similar to the peripapillary retinal nerve fiber layer (RNFL) thickness. Furthermore, decreased peripapillary vessel density of the intact hemiretina or unaffected eye of glaucomatous eyes suggests that vascular changes can occur prior to detectable visual field damage. The accuracy for glaucoma detection ...

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    4. Reasons why OCT Global Circumpapillary Retinal Nerve Fiber Layer Thickness is a Poor Measure of Glaucomatous Progression

      Reasons why OCT Global Circumpapillary Retinal Nerve Fiber Layer Thickness is a Poor Measure of Glaucomatous Progression

      Purpose: To assess the effects of local defects, segmentation errors, and improper image alignment on the performance of the commonly used optical coherence tomography (OCT) measure of progression, that is the change in global (average) circumpapillary retinal nerve fiber layer (cpRNFL) thickness (ΔG). Methods: One hundred fifty eyes suspected of, or with, early glaucoma had OCT circle and cube scans obtained using eye tracking on two occasions at least 1 year apart. Statistical progression was defined by fixed values of ΔG (3-8 um) and quantile regression. For a reference standard, four authors identified 30 eyes as "likely progressed," and 61 ...

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    5. Optical Coherence Tomography Can Be Used to Assess Glaucomatous Optic Nerve Damage in Most Eyes With High Myopia

      Optical Coherence Tomography Can Be Used to Assess Glaucomatous Optic Nerve Damage in Most Eyes With High Myopia

      Precis: It is generally assumed that optical coherence tomography ( OCT ) cannot be used to diagnose glaucomatous optic neuropathy ( GON ) in high myopes. However, this study presents evidence that there is sufficient information in OCT scans to allow for accurate diagnosis of GON in most eyes with high myopia . Purpose: The purpose of this study was to test the hypothesis that glaucomatous damage can be accurately diagnosed in most high myopes via an assessment of the OCT results. Patients and Methods: One hundred eyes from 60 glaucoma patients or suspects, referred for OCT scans and evaluation, had corrected spherical refractive errors ...

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    6. A Topographic Comparison of OCT Minimum rim Width (BMO-MRW) and Circumpapillary Retinal nerve Fiber Layer (cRNFL) Thickness Measures in Eyes with or Suspected Glaucoma

      A Topographic Comparison of OCT Minimum rim Width (BMO-MRW) and Circumpapillary Retinal nerve Fiber Layer (cRNFL) Thickness Measures in Eyes with or Suspected Glaucoma

      Précis: Bruch’s membrane opening-minimum rim width and circumpapillary retinal nerve fiber layer thickness measures may be improved by comparing probability levels and accounting for blood vessel locations. Purpose: To understand the differences between two optical coherence tomography (OCT) measures of glaucomatous damage: the Bruch’s membrane opening-minimum rim width ( BMO-MRW ) and circumpapillary retinal nerve fiber layer (cRNFL) thickness. Materialsand Methods: OCT circle scans were obtained for an early glaucoma group (EG) of 88 eyes (88 patients) with 24-2 MD better than –6.0dB, and a broader group (BG) of 188 eyes (110 patients) with 24-2 MD from -0 ...

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    7. Qualitative evaluation of neuroretinal rim and retinal nerve fibre layer on optical coherence tomography to detect glaucomatous damage

      Qualitative evaluation of neuroretinal rim and retinal nerve fibre layer on optical coherence tomography to detect glaucomatous damage

      Purpose To understand the added value of Bruch’s membrane opening-minimum rim width (BMO-MRW) measurements to conventional circumpapillary retinal nerve fibre layer (cpRNFL) thickness measurements on optical coherence tomography (OCT) imaging for discriminating between perimetric glaucoma and healthy eyes, evaluated through a qualitative evaluation. Methods 384 healthy eyes and 188 glaucoma eyes were evaluated, and glaucoma eyes were categorised as perimetric (n=107) based on a history of ≥3 consecutive abnormal 24–2 visual field tests or suspected glaucoma if they did not (n=81). OCT-derived BMO-MRW and cpRNFL reports were qualitatively evaluated by two experienced graders in isolation at ...

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    8. Macular Vascularity in Ischemic Optic Neuropathy Compared to Glaucoma by Projection-Resolved Optical Coherence Tomography Angiography

      Macular Vascularity in Ischemic Optic Neuropathy Compared to Glaucoma by Projection-Resolved Optical Coherence Tomography Angiography

      PURPOSE To compare macular vasculature in patients with primary open-angle glaucoma (POAG) POAG and atrophic non-arteritic anterior ischemic optic neuropathy (NAION). Design Prospective, cross-sectional study METHODS Thirty seven eyes with moderate and advanced POAG, 19 eyes with atrophic NAION, and 40 eyes of normal subjects were imaged using optical coherence tomography angiography (OCT-A). Macular ganglion cell complex (GCC) and peripapillary retinal nerve fiber layer (RNFL) thicknesses were measured in addition to macular superficial and deep vasculature after projection removal using custom software. RESULTS Linear models showed that while averaged peripapillary RNFL and macular GCC were not different between NAION and ...

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    9. An Examination of the Frequency of Paravascular Defects and Epiretinal Membranes in Eyes With Early Glaucoma Using En-face Slab OCT Images

      An Examination of the Frequency of Paravascular Defects and Epiretinal Membranes in Eyes With Early Glaucoma Using En-face Slab OCT Images

      Purpose: To examine the frequency of paravascular defects (PDs) and macular epiretinal membranes (ERMs) in eyes categorized as having mild glaucoma or glaucoma suspect using en-face slab analysis of optical coherence tomography (OCT) scans. Materials and Methods: Fifty-seven glaucomatous eyes, 44 low-risk suspect eyes, and 101 healthy control eyes were included in the study. The 101 glaucomatous and suspect eyes had a mean deviation better than −6 dB on the 24-2 visual field, and a spherical refractive error between±6 D or axial length <26.5 mm. Two OCT-graders masked to eye classification identified ERMs and PDs on en-face slab ...

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    10. Optical coherence tomography circle scans can be used to study many eyes with advanced glaucoma

      Optical coherence tomography circle scans can be used to study many eyes with advanced glaucoma

      Purpose To examine the utility of optical coherence tomography (OCT) for studying eyes with advanced glaucoma [i.e., eyes with a 24-2 visual field (VF) mean deviation (MD) worse than -15 dB], we tested the hypothesis that if these eyes had a 10-2 total deviation (TD) map with points better than -8 dB, then the topographically corresponding regions on the circumpapillary retinal nerve fiber layer (cpRNFL) should show a preserved region. Design Evaluation of technology study Participants 39 eyes from 33 patients (mean: 68.8 ± 9.2 years) with a diagnosis of glaucoma had a 24-2 VF with a MD ...

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    11. Optical Coherence Tomography Angiography in Papilledema Compared With Pseudopapilledema

      Optical Coherence Tomography Angiography in Papilledema Compared With Pseudopapilledema

      Purpose : The purpose of this study is to evaluate differences in optical coherence tomography angiography (OCT-A) findings between patients with papilledema and pseudopapilledema. Methods : In this prospective, comparative study, 41 eyes of 21 subjects with papilledema, 27 eyes of 15 subjects with pseudopapilledema, and 44 eyes of 44 healthy normal subjects were included and were imaged using OCT-A. In addition to peripapillary total vasculature maps obtained with commercial vessel density mapping, major vessel removal using customized image analysis software was also used to measure whole image capillary density and peripapillary capillary density (PCD). Peripapiilary retinal nerve fiber layer (RNFL) and ...

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    12. Effects of Circumpapillary Retinal Nerve Fiber Layer Segmentation Error Correction on Glaucoma Diagnosis in Myopic Eyes

      Effects of Circumpapillary Retinal Nerve Fiber Layer Segmentation Error Correction on Glaucoma Diagnosis in Myopic Eyes

      Purpose: In a myopic population, we investigated the occurrence of circumpapillary retinal nerve fiber layer (RNFL) segmentation errors that required manual correction in optical coherence tomography (OCT) and its effect on glaucoma diagnostic capability of OCT. Materials and Methods: Myopic subjects (spherical equivalent refractive error <−3 diopters) with and without primary open-angle glaucoma were recruited. Three circumpapillary RNFL scans with diameters of 3.45, 4.50, and 6.00▒mm were obtained using spectral-domain OCT. RNFL segmentation errors were manually corrected. Receiver operating characteristic curves of RNFL thickness were obtained and area under the curves (AUCs) were calculated before and ...

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    13. Noninvasive Detection of Mitochondrial Dysfunction in Ocular Hypertension and Primary Open-angle Glaucoma

      Noninvasive Detection of Mitochondrial Dysfunction in Ocular Hypertension and Primary Open-angle Glaucoma

      Purpose: To assess mitochondrial dysfunction in vivo in ocular hypertension (OHT) and primary open-angle glaucoma (POAG) using retinal metabolic analysis. Patients and Methods: This was an observational, cross-sectional study performed from November 2015 to October 2016 at the New York Eye and Ear Infirmary of Mount Sinai. Thirty-eight eyes with varying stages of POAG, 16 eyes with OHT, and 32 control eyes were imaged on a custom fundus camera modified to measure full retinal thickness fluorescence at a wavelength optimized to detect flavoprotein fluorescence (FPF). Optical coherence tomography was used to measure the retinal ganglion cell-plus layer (RGC+) thickness. Macular ...

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    14. Comparison of Widefield and Circumpapillary Circle Scans for Detecting Glaucomatous Neuroretinal Thinning on Optical Coherence Tomography

      Comparison of Widefield and Circumpapillary Circle Scans for Detecting Glaucomatous Neuroretinal Thinning on Optical Coherence Tomography

      Purpose : Our purpose was to compare the effectiveness of detecting progressive retinal nerve fiber layer (RNFL) thickness changes using widefield scans compared to circumpapillary circle scans derived from optic disc volume scans when using a manual region-of-interest (ROI) approach . Methods : In a prospective observational study, a total of 125 eyes diagnosed clinically with glaucoma or suspected glaucoma that had both widefield (12 × 9 mm) and optic disc (6 × 6 mm) scans obtained at least one year apart were included. Changes in the RNFL thickness between the two visits were evaluated within region(s) of observed or suspected glaucomatous damage, which ...

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    15. Evaluation of a Qualitative Approach for Detecting Glaucomatous Progression Using Wide-Field Optical Coherence Tomography Scans

      Evaluation of a Qualitative Approach for Detecting Glaucomatous Progression Using Wide-Field Optical Coherence Tomography Scans

      Purpose : To determine the effectiveness of detecting glaucomatous progression by a qualitative evaluation of wide-field (12 × 9 mm) scans on optical coherence tomography imaging. This method was compared to a conventional quantitative analysis of the global circumpapillary retinal nerve fiber layer (cpRNFL) thickness. Methods : A total of 409 eyes with a clinical diagnosis of glaucoma or suspected glaucoma for which two wide-field scans were obtained at least 1 year apart ( n = 125) and within one session ( n = 284) were included to determine the sensitivity of detecting progression at 95% specificity. Qualitative OCT evaluation was performed in a similar manner to ...

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    16. Optical Coherence Tomography Angiography in Optic Disc Swelling

      Optical Coherence Tomography Angiography in Optic Disc Swelling

      Purpose To compare optical coherence tomography angiography (OCT-A) of peripapillary total vasculature and capillaries in patients with optic disc swelling. Design Cross-sectional study. Methods Twenty nine eyes with acute nonarteritic anterior ischemic optic neuropathy (NAION), 44 eyes with papilledema, 8 eyes with acute optic neuritis, and 48 eyes of normal subjects were imaged using OCT-A. Peripapillary total vasculature information was recorded using a commercial vessel density map. Customized image analysis with major vessel removal was also used to measure whole-image capillary density and peripapillary capillary density (PCD). Results Mixed models showed that the peripapillary total vasculature density values were significantly ...

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    17. Evaluation of a Region-of-Interest Approach for Detecting Progressive Glaucomatous Macular Damage on Optical Coherence Tomography

      Evaluation of a Region-of-Interest Approach for Detecting Progressive Glaucomatous Macular Damage on Optical Coherence Tomography

      Purpose : To evaluate a manual region-of-interest (ROI) approach for detecting progressive macular ganglion cell complex (GCC) changes on optical coherence tomography (OCT) imaging. Methods : One hundred forty-six eyes with a clinical diagnosis of glaucoma or suspected glaucoma with macular OCT scans obtained at least 1 year apart were evaluated. Changes in the GCC thickness were identified using a manual ROI approach (ROI M ), whereby region(s) of observed or suspected glaucomatous damage were manually identified when using key features from the macular OCT scan on the second visit. Progression was also evaluated using the global GCC thickness and an automatic ...

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    18. Association of Myopia With Peripapillary Perfused Capillary Density in Patients With Glaucoma An Optical Coherence Tomography Angiography Study

      Association of Myopia With Peripapillary Perfused Capillary Density in Patients With Glaucoma An Optical Coherence Tomography Angiography Study

      Importance This study used optical coherence tomographic angiography to assess for impaired blood flow in myopic eyes with or without open-angle glaucoma. Objective To compare the peripapillary perfused capillary density (PCD) between eyes with and without glaucoma. Design, Setting, and Participants In this cross-sectional study at a tertiary glaucoma referral practice, we recruited patients with myopic eyes of spherical equivalent of more than −3.0 diopters with and without open-angle glaucoma, patients with nonmyopic eyes with glaucoma, and patients with no disease from February 2016 to October 2016. We obtained 4.5 × 4.5-mm optical coherence tomographic angiography images of ...

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    19. Detecting Glaucomatous Progression With a Region-of-Interest Approach on Optical Coherence Tomography: A Signal-to-Noise Evaluation

      Detecting Glaucomatous Progression With a Region-of-Interest Approach on Optical Coherence Tomography: A Signal-to-Noise Evaluation

      Purpose : To compare two region-of-interest (ROI) approaches and a global thickness approach for capturing progressive circumpapillary retinal nerve fiber layer (cpRNFL) changes on optical coherence tomography (OCT) imaging. Methods : Progressive cpRNFL thickness changes were evaluated in 164 eyes with a clinical diagnosis of glaucoma or suspected glaucoma; all eyes underwent optic disc OCT imaging on two visits at least 1 year apart. Such changes were evaluated with a manual ROI approach (ROI M ), which involved manual identification of region(s) of observed or suspected glaucomatous damage. The ROI M was compared with an automatic ROI approach (ROI A ), where regions ...

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    20. Peripapillary Perfused Capillary Density in Exfoliation Syndrome and Exfoliation Glaucoma versus POAG and Healthy Controls: An OCTA Study

      Peripapillary Perfused Capillary Density in Exfoliation Syndrome and Exfoliation Glaucoma versus POAG and Healthy Controls: An OCTA Study

      PURPOSE: To compare the peripapillary perfused capillary density (PCD) among eyes with exfoliation syndrome (XFS), exfoliation glaucoma (XFG), primary open-angle glaucoma (POAG), and controls. DESIGN: Observational, cross-sectional study. METHODS: Optical coherence tomography angiography (OCTA) images (4.5×4.5 mm) of the optic nerve head were obtained using a commercial spectral domain OCTA system (AngioVue Avanti RTVue-XR, OptoVue, Fremont, CA). Two concentric circles with 1.95-mm (inner) and 3.45-mm (outer) diameters were placed manually, producing an annulus of width 0.75 mm centered at the optic disc. PCD was calculated as the ratio of pixels associated with capillaries to ...

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    21. Imaging Congenital Optic Disc Pits and Associated Maculopathy Using Optical Coherence Tomography

      Imaging Congenital Optic Disc Pits and Associated Maculopathy Using Optical Coherence Tomography

      Objective: To elucidate the anatomy of congenital optic disc pits with and without maculopathy using optical coherence tomography. Setting: All patients were examined, photographed, and scanned at the New York Eye and Ear Infirmary. Patients: Ten eyes of eight consecutive patients with congenital optic disc pits were studied. Three eyes had associated serous macular detachment (group 1), four had evidence of resolved detachment (group 2), and three had no clinical macular pathologic lesion (group 3). Methods: Optical coherence tomography, a new, noninvasive, noncontact, imaging technology capable of producing cross-sectional images of the retina in vivo with high resolution (<17 μm ...

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    22. A Novel Method for Assessing Lamina Cribrosa Structure Ex Vivo Using Anterior Segment Enhanced Depth Imaging Optical Coherence Tomography

      A Novel Method for Assessing Lamina Cribrosa Structure Ex Vivo Using Anterior Segment Enhanced Depth Imaging Optical Coherence Tomography

      Purpose: The purpose of this study is to investigate the use of anterior segment enhanced depth imaging (EDI) optical coherence tomography (OCT) for ex vivo lamina cribrosa (LC) imaging. Materials and Methods: After removing anterior segment and vitreous, the optic nerve head (ONH) tissue of porcine eyes was placed on a customized eye holder for imaging. Serial EDI OCT B-scans (interval, ~35 [mu]m) of the ONH were obtained using anterior segment module of spectral-domain OCT. Various conditions were tested for better quality LC images. After EDI OCT, serial histologic sections were obtained (distance between sections, ~5 [mu]m). LC ...

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    23. The Association Between Clinical Features Seen on Fundus Photographs and Glaucomatous Damage Detected on Visual Fields and Optical Coherence Tomography Scans

      The Association Between Clinical Features Seen on Fundus Photographs and Glaucomatous Damage Detected on Visual Fields and Optical Coherence Tomography Scans

      Purpose: To classify the appearance of the optic disc seen on fundus photographs of healthy subjects and patients with or suspected glaucoma whose diagnosis was based upon visual fields (VFs) and spectral-domain optical coherence tomography (sdOCT) results. Patients and Methods: One eye of 100 patients with or suspected glaucoma and 62 healthy subjects were prospectively tested with 24-2 and 10-2 VF and macular and disc sdOCT cube scans. All eyes with or suspected glaucoma had a 24-2 mean deviation better than −6.0 dB and an abnormal appearing disc on stereophotographs. The retinal ganglion cell plus inner plexiform layer (RGC ...

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    24. Optical Coherence Tomography and Glaucoma Progression: A Comparison of a Region of Interest Approach to Average Retinal Nerve Fiber Layer Thickness

      Optical Coherence Tomography and Glaucoma Progression: A Comparison of a Region of Interest Approach to Average Retinal Nerve Fiber Layer Thickness

      PURPOSE To determine whether the change in the retinal nerve fiber layer (RNFL) thickness in a region of interest (ROI) is a better measure of glaucoma progression than the change in average circumpapillary (cp) RNFL thickness. METHODS Disc cube scans were obtained with frequency domain optical coherence tomography from 60 eyes of 60 patients (age, 61.7±12.7 y) with early or suspected glaucoma and controlled intraocular pressure. The average time between 2 test dates was 3.2±1.8 years. En-face images of the scans from the 2 tests were aligned based on the blood vessels, and cp ...

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    1-24 of 62 1 2 3 »
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