1. Articles from Randy H. Kardon

    1-18 of 18
    1. Optical coherence tomography is highly sensitive in detecting prior optic neuritis

      Optical coherence tomography is highly sensitive in detecting prior optic neuritis

      Objective To explore sensitivity of optical coherence tomography (OCT) in detecting prior unilateral optic neuritis. Methods This is a retrospective, observational clinical study of all patients who presented from January 1, 2014, to January 6, 2017, with unilateral optic neuritis and OCT available at least 3 months after the attack. We compared OCT retinal nerve fiber layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) thicknesses between affected and unaffected contralateral eyes. We excluded patients with concomitant glaucoma or other optic neuropathies. Based on analysis of normal controls, thinning was considered significant if RNFL was at least 9 µm or ...

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      Mentions: Randy H. Kardon
    2. Optical Coherence Angiographic Demonstration of Retinal Changes From Chronic Optic Neuropathies

      Optical Coherence Angiographic Demonstration of Retinal Changes From Chronic Optic Neuropathies

      Glaucoma causes a decrease in peripapillary perfused capillary density on optical coherence tomography (OCT) angiography. However, other chronic optic neuropathies have not been explored with OCT angiography to see if these changes were specific to glaucoma. The authors evaluated OCT angiography in 10 patients who suffered various kinds of chronic optic neuropathies, including optic neuritis and ischaemic optic neuropathy, and found that all optic neuropathies showed a decrease in peripapillary vessel density on OCT angiography, regardless of the aetiology of the optic neuropathy. The peripapillary vessel loss on OCT angiography correlated well with the areas of retinal nerve fibre layer ...

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    3. Avoiding Clinical Misinterpretation and Artifacts of Optical Coherence Tomography Analysis of the Optic Nerve, Retinal Nerve Fiber Layer, and Ganglion Cell Layer

      Avoiding Clinical Misinterpretation and Artifacts of Optical Coherence Tomography Analysis of the Optic Nerve, Retinal Nerve Fiber Layer, and Ganglion Cell Layer

      Background: Optical coherence tomography (OCT) has become an important tool for diagnosing optic nerve disease. The structural details and reproducibility of OCT continues to improve with further advances in technology. However, artifacts and misinterpretation of OCT can lead to clinical misdiagnosis of diseases if they go unrecognized. Evidence Acquisition: A literature review using PubMed combined with clinical and research experience. Results: We describe the most common artifacts and errors in interpretation seen on OCT in both optic nerve and ganglion cell analyses. We provide examples of the artifacts, discuss the causes, and provide methods of detecting them. In addition, we ...

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    4. The Pattern of Visual Fixation Eccentricity and Instability in Optic Neuropathy and Its Spatial Relationship to Retinal Ganglion Cell Layer Thickness

      The Pattern of Visual Fixation Eccentricity and Instability in Optic Neuropathy and Its Spatial Relationship to Retinal Ganglion Cell Layer Thickness

      Purpose : The purpose of this study was to assess whether clinically useful measures of fixation instability and eccentricity can be derived from retinal tracking data obtained during optical coherence tomography (OCT) in patients with optic neuropathy (ON) and to develop a method for relating fixation to the retinal ganglion cell complex (GCC) thickness. Methods : Twenty-nine patients with ON underwent macular volume OCT with 30 seconds of confocal scanning laser ophthalmoscope (cSLO)-based eye tracking during fixation. Kernel density estimation quantified fixation instability and fixation eccentricity from the distribution of fixation points on the retina. Preferred ganglion cell layer loci (PGCL ...

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    5. Combined use of high-density and volumetric optical coherence tomography for the segmentation of neural canal opening in cases of optic nerve edema

      Combined use of high-density and volumetric optical coherence tomography for the segmentation of neural canal opening in cases of optic nerve edema

      In cases of optic-nerve-head edema, the presence of the swelling reduces the visibility of the underlying neural canal opening (NCO) within spectral-domain optical coherence tomography (SD-OCT) volumes. Consequently, traditional SD-OCT-based NCO segmentation methods often overestimate the size of the NCO. The visibility of the NCO can be improved using high-definition 2D raster scans, but such scans do not provide 3D contextual image information. In this work, we present a semi-automated approach for the segmentation of the NCO in cases of optic disc edema by combining image information from volumetric and high-definition raster SD-OCT image sequences. In particular, for each subject ...

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    6. Homonymous Ganglion Cell Layer Thinning After Isolated Occipital Lesion: Macular OCT Demonstrates Transsynaptic Retrograde Retinal Degeneration

      Homonymous Ganglion Cell Layer Thinning After Isolated Occipital Lesion: Macular OCT Demonstrates Transsynaptic Retrograde Retinal Degeneration

      A 48-year-old man was examined 24 months after medial and surgical treatment of an isolated well-circumscribed right occipital lobe abscess. An asymptomatic residual left homonymous inferior scotoma was present. Fundus examination revealed temporal pallor of both optic discs, and optical coherence tomography (OCT) revealed mild temporal loss of retinal nerve fiber layer in both eyes. No relative afferent pupillary defect was present. Assessment of the retinal ganglion cell layer demonstrated homonymous thinning in a pattern corresponding to the homonymous visual field loss. There were no abnormalities of the lateral geniculate nuclei or optic tracts on review of the initial brain ...

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      Mentions: Randy H. Kardon
    7. Scanning Laser Polarimetry, but not Optical Coherence Tomography Predicts Permanent Visual Field Loss in Acute Non-Arteritic Anterior Ischemic Optic Neuropathy

      Scanning Laser Polarimetry, but not Optical Coherence Tomography Predicts Permanent Visual Field Loss in Acute Non-Arteritic Anterior Ischemic Optic Neuropathy

      Purpose Scanning laser polarimetry (SLP) reveals abnormal retardance of birefringence in locations of the edematous peripapillary retinal nerve fiber layer (RNFL), which appear thickened by OCT, in non-arteritic anterior ischemic optic neuropathy (NAION). We hypothesize initial sector SLP RNFL abnormalities will correlate with long-term regional visual field loss due to ischemic injury. Methods We prospectively performed automated perimetry, SLP and HD- OCT of the RNFL in 25 eyes with acute NAION. We grouped visual field threshold and RNFL values into Garway-Heath inferior/superior disc sectors and corresponding superior/inferior field regions. We compared sector SLP RNFL thickness with corresponding visual ...

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    8. Effectiveness of averaging strategies to reduce variance in retinal nerve fibre layer thickness measurements using spectral-domain optical coherence tomography

      Effectiveness of averaging strategies to reduce variance in retinal nerve fibre layer thickness measurements using spectral-domain optical coherence tomography

      Background Automated detection of subtle changes in peripapillary retinal nerve fibre layer thickness (RNFLT) over time using optical coherence tomography (OCT) is limited by inherent image quality before layer segmentation, stabilization of the scan on the peripapillary retina and its precise placement on repeated scans. The present study evaluates image quality and reproducibility of spectral domain (SD)-OCT comparing different rates of automatic real-time tracking (ART). Methods Peripapillary RNFLT was measured in 40 healthy eyes on six different days using SD-OCT with an eye-tracking system. Image brightness of OCT with unaveraged single frame B-scans was compared to images using ART ...

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    9. Automated 3D region-based volumetric estimation of optic disc swelling in papilledema using spectral-domain optical coherence tomography

      Automated 3D region-based volumetric estimation of optic disc swelling in papilledema using spectral-domain optical coherence tomography

      The six-stage Frisén scale is a qualitative and subjective method for assessing papilledema (optic disc swelling due to raised intracranial pressure) using fundus photographs. The recent introduction of spectral-domain optical coherence tomography (SD-OCT) presents a promising alternative to enable the 3-D quantitative estimation of papilledema. In this work, we propose an automated region-based volumetric estimation of the degree of papilledema from SD-OCT. After using a custom graph-based approach to segment the surfaces of the swollen optic nerve head, the volumes of the nasal, superior, temporal, and inferior regions are computed. Using a dataset of 70 SD-OCT optic-nerve-head (ONH) SD-OCT ...

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    10. Characterization of structure and function of the mouse retina using pattern electroretinography, pupil light reflex, and optical coherence tomography

      Characterization of structure and function of the mouse retina using pattern electroretinography, pupil light reflex, and optical coherence tomography

      Objective  To perform in vivo analysis of retinal functional and structural parameters in healthy mouse eyes. Animal Studied  Adult C57BL/6 male mice (n = 37). Procedures  Retinal function was evaluated using pattern electroretinography (pERG) and the chromatic pupil light reflex (cPLR). Structural properties of the retina and nerve fiber layer (NFL) were evaluated using spectral-domain optical coherence tomography (SD-OCT). Results  The average pERG amplitudes were found to be 11.2 ± 0.7 μV (P50-N95, mean ± SEM), with an implicit time for P50-N95 interval of 90.4 ± 5.4 ms. Total retinal thickness was 229.5 ± 1.7 μm (mean ± SEM ...

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    11. Automated Quantification of Volumetric Optic Disc Swelling in Papilledema Using Spectral-Domain Optical Coherence Tomography

      Automated Quantification of Volumetric Optic Disc Swelling in Papilledema Using Spectral-Domain Optical Coherence Tomography

      Purpose: To develop an automated method for the quantification of volumetric optic disc swelling in papilledema subjects using spectral-domain optical coherence tomography (SD-OCT) and to determine the extent that such volumetric measurements correlate with Frisén scale grades (from fundus photographs) and 2-D peripapillary retinal-nerve-fiber-layer (RNFL) and total-retinal (TR) thickness measurements from SD-OCT. Methods: A custom image-analysis algorithm was developed to obtain peripapillary circular RNFL thickness, TR thickness, and TR volume measurements from SD-OCT volumes of subjects with papilledema. In addition, peripapillary RNFL thickness measures from the commercially available Zeiss SD-OCT machine were obtained. Expert Frisén scale grades were independently obtained ...

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    12. Scanning Laser Polarimetry Reveals Status of Retinal Nerve Fiber Layer (RNFL) Integrity in Eyes with Optic Nerve Head Swelling by OCT

      Scanning Laser Polarimetry Reveals Status of Retinal Nerve Fiber Layer (RNFL) Integrity in Eyes with Optic Nerve Head Swelling by OCT

      Purpose OCT shows retinal nerve fiber layer (RNFL) thickening in optic nerve head (ONH) swelling, but does not provide information on acute axonal disruption. We hypothesized that scanning laser polarimetry (SLP) in comparison with OCT might reveal the status of axon integrity and visual prognosis in acute RNFL swelling. Methods We used threshold perimetry, OCT, and SLP to prospectively study eyes with papilledema (24), optic neuritis (13), NAION (21), and ONH swelling (defined as having average RNFL by OCT > 95th percentile of controls at presentation). Regional RNFL was judged reduced if the OCT or SLP measure in a quadrant was < 5th percentile of controls. Results At presentation, average RNFL by OCT was similar for eyes with papilledema and NAION (p=0.97), and less for optic neuritis. Average RNFL by SLP was less often increased, similar for papilledema and optic neuritis, but less for NAION (p=0.02) eyes. The RNFL by SLP was reduced in at least 1 quadrant in 1/24 eyes with papilledema, 1/14 eyes with optic neuritis, and in 13/21 eyes with NAION. In NAION eyes, quadrants with reduced SLP had corresponding visual field loss that did not recover at 1 or 6 months. By 1 month, eyes with NAION showed RNFL thinning by OCT (7/17 eyes) and by SLP in14/16 eyes) in contrast to optic neuritis (by OCT, 0/12; p=0.006 and by SLP, 1/12; p=0.0004). Conclusion OCT and SLP reveal different aspects of RNFL changes associated with ONH swelling. OCT reveals thickening, due to edema. SLP reveals a decrease in retardance in eyes with axonal injury associated with visual field loss, which is unlikely to recover. This study provides evidence that SLP may be predictive of regions of permanent axon dysfunction and visual field loss in eyes with optic disc edema.

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    13. Retinal Ganglion Cell Layer Thickness and Local Visual Field Sensitivity in Glaucoma

      Retinal Ganglion Cell Layer Thickness and Local Visual Field Sensitivity in Glaucoma

      Objective To compare loss in sensitivity measured using standard automated perimetry (SAP) with local retinal ganglion cell layer (RGC) thickness measured using frequency-domain optical coherence tomography in the macula of patients with glaucoma. Methods To compare corresponding locations of RGC thickness with total deviation (TD) of 10-2 SAP for 14 patients with glaucoma and 19 controls, an experienced operator hand-corrected automatic segmentation of the combined RGC and inner plexiform layer (RGC+IPL) of 128 horizontal B-scans. To account for displacement of the RGC bodies around the fovea, the location of the SAP test points was adjusted to correspond to the ...

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    14. Vision in Multiple Sclerosis: The Story, Structure-Function Correlations, and Models for Neuroprotection

      Vision in Multiple Sclerosis: The Story, Structure-Function Correlations, and Models for Neuroprotection
      Abstract: Visual dysfunction is one of the most common clinical manifestations of multiple sclerosis (MS). Just over a decade ago, MS clincial trials did not include visual outcomes, but experts recognized the need for more sensitive measures of visual function. Low-contrast letter acuity emerged as the leading candidate to measure visual disability in MS, and subsequent studies found low-contrast acuity testing to correlate well with brain MRI lesion burden, visual-evoked potentials, quality of life (QOL), and retinal nerve fiber layer (RNFL) loss, as measured by optical coherence tomography (OCT). OCT in MS has allowed for assessment of structure-function correlations that ...
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    15. Role of the Macular Optical Coherence Tomography Scan in Neuro-Ophthalmology

      Role of the Macular Optical Coherence Tomography Scan in Neuro-Ophthalmology
      Background: Recent improvements in optical coherence tomographic (OCT) resolution and automated segmentation software have provided a means of relating visual pathway damage to structural changes in the retinal nerve fiber layer (RNFL) and corresponding soma of the ganglion cells in the inner layers of the macula and also in the outer photoreceptor layer in the macula. Evidence Acquisition: Studies correlating retinal structure with function are reviewed in the context of OCT in optic nerve and retinal disorders. Results: Recently published work provides evidence showing a strong relationship not only between the RNFL and visual threshold in optic nerve disorders but ...
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    16. Optical coherence tomography of the swollen optic nerve head: deformation of the peripapillary RPE layer in papilledema

      Optical coherence tomography of the swollen optic nerve head: deformation of the peripapillary RPE layer in papilledema

      Purpose: To examine the biomechanical deformation of load bearing structures of the optic nerve head (ONH) resulting from raised intracranial pressure, using high definition optical coherence tomography (HD-OCT). We postulate that elevated intracranial pressure induces forces in the retrolaminar subarachnoid space that can deform ONH structures, particularly the peripapillary Bruch's membrane (BM) and retinal pigment epithelium (RPE) layers. Methods: We compared HD-OCT optic nerve and peripapillary retinal nerve fiber layer (RNFL) findings in eyes with papilledema due to raised intracranial pressure to findings in eyes with optic disc swelling due to optic neuritis and non-arteritic anterior ischemic optic neuropathy ...

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    17. Diagnosis and Grading of Papilledema in Patients With Raised Intracranial Pressure Using Optical Coherence Tomography vs Clinical Expert Assessment Using a Clinical Staging Scale]

      Diagnosis and Grading of Papilledema in Patients With Raised Intracranial Pressure Using Optical Coherence Tomography vs Clinical Expert Assessment Using a Clinical Staging Scale]
      Objectives  To compare and contrast 2 methods of quantitating papilledema, namely, optical coherence tomography (OCT) and Modified Frisén Scale (MFS). Methods  Digital optic disc photographs and OCT fast retinal nerve fiber layer (RNFL) thickness, fast RNFL map, total retinal thickness, and fast disc images were obtained in 36 patients with papilledema. Digital optic disc photographs were randomized and graded by 4 masked expert reviewers using the MFS. We performed Spearman rank correlations of OCT RNFL thickness, OCT total retinal thickness, and MFS grade from photographs. Results  OCT RNFL thickness and MFS grade from photographs correlated well (R = 0.85). OCT ...
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    18. A Test of a Linear Model of Glaucomatous Structure–Function Loss Reveals Sources of Variability in Retinal Nerve Fiber and Visual Field Measurements

      PURPOSE. Retinal nerve fiber (RNFL) thickness and visual field loss data from patients with glaucoma were analyzed in the context of a model, to better understand individual variation in structure versus function. METHODS. Optical coherence tomography (OCT) RNFL thickness and standard automated perimetry (SAP) visual field loss were measured in the arcuate regions of one eye of 140 patients with glaucoma and 82 normal control subjects. An estimate of within-individual (measurement) error was obtained by repeat measures made on different days within a short period in 34 patients and 22 control subjects. A linear model, previously shown to describe the ...
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    1-18 of 18
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    Diagnosis and Grading of Papilledema in Patients With Raised Intracranial Pressure Using Optical Coherence Tomography vs Clinical Expert Assessment Using a Clinical Staging Scale] Optical coherence tomography of the swollen optic nerve head: deformation of the peripapillary RPE layer in papilledema Role of the Macular Optical Coherence Tomography Scan in Neuro-Ophthalmology Vision in Multiple Sclerosis: The Story, Structure-Function Correlations, and Models for Neuroprotection Retinal Ganglion Cell Layer Thickness and Local Visual Field Sensitivity in Glaucoma Scanning Laser Polarimetry Reveals Status of Retinal Nerve Fiber Layer (RNFL) Integrity in Eyes with Optic Nerve Head Swelling by OCT Automated Quantification of Volumetric Optic Disc Swelling in Papilledema Using Spectral-Domain Optical Coherence Tomography Characterization of structure and function of the mouse retina using pattern electroretinography, pupil light reflex, and optical coherence tomography Automated 3D region-based volumetric estimation of optic disc swelling in papilledema using spectral-domain optical coherence tomography Optical coherence tomography angiography of foveal neovascularisation in proliferative diabetic retinopathy Treating port wine stain birthmarks using dynamic optical coherence tomography-guided setting Repeatability of quantitative measurements of retinal layers with SD-OCT and agreement between vertical and horizontal scan protocols in healthy eyes