1. Articles in category: Neurology

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    1. Demonstration of the time course of retrograde trans-synaptic degeneration in the visual system using optical coherence tomography

      Demonstration of the time course of retrograde trans-synaptic degeneration in the visual system using optical coherence tomography
      26 patients were recruited following acute unilateral damage to the postgeniculate visual pathway (onset 12–50 years prior to testing) together with age and sex matched controls. Peripapillary retinal nerve fibre layer (RNFL) thickness was measured with optical coherence tomography on a single occasion. (2) 7 of the 26 patients and a further 4 patients with incomplete hemianopia were recruited within 5 months of the injury (range 5–177 days). In this group the RNFL thickness was measured serially for at least 43 days (range 43–876 days) to study the rate of change. Results (1) There is a negative ...
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    2. Heterogeneous patterns of tissue injury in NARP syndrome

      Heterogeneous patterns of tissue injury in NARP syndrome

      Point mutations at m.8993T>C and m.8993T>G of the mtDNA ATPase 6 gene cause the neurogenic weakness, ataxia and retinitis pigmentosa (NARP) syndrome, a mitochondrial disorder characterized by retinal, central and peripheral neurodegeneration. We performed detailed neurological, neuropsychological and ophthalmological phenotyping of a mother and four daughters with NARP syndrome from the mtDNA m.8993T>C ATPase 6 mutation, including 3-T brain MRI, spectral domain optical coherence tomography (SD-OCT), adaptive optics scanning laser ophthalmoscopy (AOSLO), electromyography and nerve conduction studies (EMG-NCS) and formal neuropsychological testing. The degree of mutant heteroplasmy for the m.8993T>C mutation was ...

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    3. Associations between retinal nerve fiber layer abnormalities and optic nerve examination

      Associations between retinal nerve fiber layer abnormalities and optic nerve examination
      Objective: Retinal nerve fiber layer (RNFL) abnormalities detected by optical coherence tomography (OCT) are useful markers for axonal loss and visual dysfunction in multiple sclerosis (MS), but their role in routine clinical management is not well-studied. Methods: Clinical and OCT examinations were performed on 240 patients attending a neurology clinic. Using OCT 5th percentile to define abnormal RNFL thickness, we compared eyes classified by neurologists as having optic atrophy to RNFL thickness, and afferent pupillary defect (APD) to RNFL thickness ratios of eye pairs. Results: Mean RNFL thickness was less in eyes classified by neurologists as having optic atrophy (79 ...
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    4. In vivo rat brain measurements of changes in signal intensity depth profiles as a function of temperature using wide-field optical coherence tomography

      In vivo rat brain measurements of changes in signal intensity depth profiles as a function of temperature using wide-field optical coherence tomography
      In our previous study, we used optical coherence tomography (OCT) and reported an increase in signal intensity of depth profiles between euthanasia injection and cardiac arrest (CA), demonstrating the potential as a tool for monitoring/diagnosing brain tissue viability [Appl. Opt.48, 4354 (2009)APOPAI0003-693510.1364/AO.48.004354]. Here, for the first time to our knowledge, we measured three-dimensional (3D) OCT images through a thinned skull changing temperatures in the rat brain. The measurements were made at 10min intervals for 210min to evaluate correlations of temperature with heart rate and ratios of signal intensity (RSI). The 3D image area ...
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    5. Disease activity in idiopathic intracranial hypertension: a 3-month follow-up study

      Disease activity in idiopathic intracranial hypertension: a 3-month follow-up study

      Idiopathic intracranial hypertension (IIH) is a disorder of raised intracranial pressure (ICP) in the absence of identifiable pathology. The purpose of this study was to evaluate the clinical presentation and monitor a 3-month course using frequent optical coherence tomography (OCT) evaluations, visual field testings and lumbar opening pressure measurements. A longitudinal study of 17 patients with newly diagnosed IIH and 20 healthy overweight controls were included in the study. Peripapillary retinal nerve fiber layer thickness (RNFLT) and retinal thickness (RT) measurements (Stratus OCT-3, fast RNFL 3.4 protocol), and Humphrey visual field testing were evaluated at regular intervals. Repeat lumbar ...

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    6. Retinal nerve fiber layer evaluation in multiple sclerosis with spectral domain optical coherence tomography

      Retinal nerve fiber layer evaluation in multiple sclerosis with spectral domain optical coherence tomography
      Purpose: Histopathologic studies have reported retinal nerve fiber layer (RNFL) thinning in various neurodegenerative diseases. Attempts to quantify this loss in vivo have relied on ­time-domain optical coherence tomography (TDOCT), which has low resolution and requires substantial interpolation of data for volume measurements. We hypothesized that the significantly higher resolution of spectral-domain optical coherence tomography (SDOCT) would better detect RNFL changes in patients with multiple sclerosis, and that RNFL thickness differences between eyes with and without optic neuritis might be identified more accurately. Methods: In this retrospective case series, patients with multiple sclerosis were recruited from the Judith Jaffe Multiple ...
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    7. Using retinal architecture to help characterize multiple sclerosis patients

      Using retinal architecture to help characterize multiple sclerosis patients

      Objective: We compared retinal nerve fibre layer (RNFL) thickness and visual function in a heterogeneous multiple sclerosis (MS) cohort to determine whether optical coherence tomography (OCT) may complement the existing methods used to characterize MS patients. Design: Cross-sectional cohort study. Participants: One hundred and ninety-three patients with optic neuritis (ON) as a clinically isolated syndrome (CIS) (n = 63), relapsing-remitting MS (RRMS) (n = 108), secondary progressive MS (SPMS) (n = 13), and primary progressive MS (PPMS) (n = 9). Methods: All patients underwent standardized ophthalmic, neurological, and OCT testing at a single academic institution. Results: RNFL values were reduced in PPMS (94.3 ...

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    8. Measurement of signal intensity depth profiles in rat brains with cardiac arrest maintaining primary temperature by wide-field optical coherence tomography

      Measurement of signal intensity depth profiles in rat brains with cardiac arrest maintaining primary temperature by wide-field optical coherence tomography
      We have already reported that after an injection for euthanasia, the signal intensity of optical coherence tomography (OCT) images are 2.7 times increased before cardiac arrest (CA) using OCT and rat brains without temperature control to show the potential of OCT to monitor tissue viability in brains [Appl. Opt. 48, 4354 (2009)]. In this paper, we similarly measured maintaining the primary temperature of rat brains. It was confirmed that when maintaining the primary temperature, the time courses of the ratios of signal intensity (RSIs) were almost the same as those without temperature control. RSIs after CA varied from 1 ...
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    9. A serial study of retinal changes following optic neuritis with sample size estimates for acute neuroprotection trials

      A serial study of retinal changes following optic neuritis with sample size estimates for acute neuroprotection trials
      Following an episode of optic neuritis, thinning of the retinal nerve fibre layer, which indicates axonal loss, is observed using optical coherence tomography. The longitudinal course of the retinal changes has not been well characterized. We performed a serial optical coherence tomography study in patients presenting with optic neuritis in order to define the temporal evolution of retinal nerve fibre layer changes and to estimate sample sizes for proof-of-concept trials of neuroprotection using retinal nerve fibre layer loss as the outcome measure. Twenty-three patients (7 male, 16 female, mean age 31 years) with acute clinically isolated unilateral optic neuritis were ...
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    10. Optical coherence tomography in multiple sclerosis: a systematic review and meta-analysis

      Optical coherence tomography in multiple sclerosis: a systematic review and meta-analysis

      Optical coherence tomography (OCT) is a new method that could aid analysis of neurodegeneration in multiple sclerosis (MS) by capturing thinning of the retinal nerve fibre layer (RNFL). Meta-analyses of data for time domain OCT show RNFL thinning of 20·38 μm (95% CI 17·91—22·86, n=2063, p<0·0001) after optic neuritis in MS, and of 7·08 μm (5·52—8·65, n=3154, p<0·0001) in MS without optic neuritis. The estimated RNFL thinning in patients with MS is greater than the extent expected in normal ageing, probably because of retrograde trans-synaptic degeneration ...

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    11. Reproducibility of high-resolution optical coherence tomography in multiple sclerosis

      Reproducibility of high-resolution optical coherence tomography in multiple sclerosis

      Optical coherence tomography (OCT) is a non-invasive method to quantify neurodegeneration as an outcome in multiple sclerosis clinical trials; however, no data exist on Cirrus spectral domain optical coherence tomography (SD-OCT) reproducibility in patients with multiple sclerosis. The objective of this study was to determine the protocol for achieving optimal inter-visit, inter-rater, and intra-rater reproducibility for studies performed on healthy controls and multiple sclerosis patients utilizing novel high-definition SD-OCT. This is a prospective study of inter-visit, inter-rater, and intra-rater reproducibility in multiple sclerosis patients (n = 58) and healthy controls (n = 32) on Cirrus-HD SD-OCT. Excellent reproducibility of average and quadrantic ...

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    12. Simple Eye Test Measures Damage from Multiple Sclerosis

      Simple Eye Test Measures Damage from Multiple Sclerosis

      A quick, painless eye measurement shows promise as a way to diagnose multiple sclerosis in its very early stages, and to track the effectiveness of treatments, researchers from UT Southwestern Medical Center have found in a multicenter study. “This technique has the potential to provide a powerful and reliable assessment strategy to measure structural changes in the central nervous system, both for diagnostic purposes and in clinical trials to monitor whether potential treatments can prevent deterioration or restore nerve function,” said Dr. Elliot Frohman, professor of neurology and ophthalmology, director of the Multiple Sclerosis Clinical Center at UT Southwestern and ...

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    13. Comparison of Optical Coherence Tomography and Scanning Laser Polarimetry Measurements in Patients with Multiple Sclerosis

      Comparison of Optical Coherence Tomography and Scanning Laser Polarimetry Measurements in Patients with Multiple Sclerosis
      Purpose. To compare optical coherence tomography (OCT) and scanning laser polarimetry (GDx) measurements of the retinal nerve fiber layer (RNFL) in multiple sclerosis (MS) patients with and without optic neuritis (ON). Methods. OCT and GDx were performed on 68 MS patients. Qualifying eyes were divided into two groups: 51 eyes with an ON history >=6 months before (ON eyes) and 65 eyes with no history of ON (non-ON eyes). Several GDx and OCT parameters and criteria were used to define an eye as abnormal, for example, GDx nerve fiber indicator (NFI) >20 or 30, OCT average RNFL thickness, and GDx ...
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    14. Fiber spectral domain optical coherence tomography for in vivo rat brain imaging

      Fiber spectral domain optical coherence tomography for in vivo rat brain imaging
      A well established navigation method is one of the key conditions for successful brain surgery: It should be accurate, safe and online operable. Recent research shows that Optical Coherence Tomography is a potential solution for this application by providing a high resolution and small probe dimension. In this study a fiber Spectral-Domain OCT system with a super luminescent diode with the center wavelength of 840 nm providing 13.6 µm axial resolution was used. A single mode fiber (Ø 125 µm) was employed as the detecting probe. The information acquired by OCT was reconstructed into grayscale images by vertically aligning ...
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    15. Retinal nerve fiber layer thickness in subgroups of multiple sclerosis, measured by optical coherence tomography and scanning laser polarimetry

      Retinal nerve fiber layer thickness in subgroups of multiple sclerosis, measured by optical coherence tomography and scanning laser polarimetry
      Abstract  Optical coherence tomography (OCT) and scanning laser polarimetry (GDx ECC) are non-invasive methods used to assess retinal nerve fiber layer (RNFL) thickness, which may be a reliable tool used to monitor axonal loss in multiple sclerosis (MS). The objectives of this study are (1) to compare OCT with the GDx ECC; (2) to assess and compare the RNFL thickness in subgroups of MS. Ophthalmologic examination and RNFL assessment by OCT and GDx were performed in 65 MS patients (26 relapsing-remitting (RRMS), ten secondary-progressive (SPMS), 29 primary-progressive (PPMS)). Twenty-eight patients (43%) had a history of optic neuritis (ON). Adjustments were ...
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    16. Patterns of retinal nerve fiber layer loss in multiple sclerosis patients with or without optic neuritis and glaucoma patients

      Patterns of retinal nerve fiber layer loss in multiple sclerosis patients with or without optic neuritis and glaucoma patients

      OBJECTIVE: Optical coherence tomography (OCT) has gained increasing attention in multiple sclerosis (MS) research and has been suggested as outcome measure for neuroprotective therapies. However, to date it is not clear whether patterns of retinal nerve fiber layer thickness (RNFLT) loss are different in MS compared to other diseases such as glaucoma and data on RNFLT loss in MS patients with or without optic neuritis (ON/NON) have remained inconsistent or even contradictory. METHODS: In this large cross-sectional study we analyzed the patterns of axonal loss of retinal ganglion cells in MS eyes (n=262) with and without history of ...

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      Mentions: Friedemann Paul
    17. Preliminary investigation on use of high-resolution optical coherence tomography to monitor injury and repair in the rat sciatic nerve

      Preliminary investigation on use of high-resolution optical coherence tomography to monitor injury and repair in the rat sciatic nerve
      Background and Objective Optical coherence tomography (OCT) has been used in limited settings to study peripheral nerve injury. The purpose of the study is to determine whether high-resolution OCT can be used to monitor nerve injury and regeneration in the rat sciatic nerve following crush injury, ligation, and transection with microsurgical repair. Study Design/Materials and Methods Forty-five rats were segregated into three groups. The right sciatic nerve was suture ligated (n = 15), cut then microsurgically repaired (n = 15), or crushed (n = 15). The left sciatic nerve served as the control; only surgical exposure and skin closure were performed. Each ...
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    18. Optic coherence tomography as a potential readout in clinical trials

      Optic coherence tomography as a potential readout in clinical trials
      Optical coherence tomography (OCT) is a noninvasive tool used for measuring tissue at micrometer resolution. It has been extensively applied to ocular pathologies and is now being studied as a biomarker in various neurologic conditions. The retina represents a unique environment for study, with unmyelinated axons that directly synapse into the central nervous system. When trying to quantify axonal degradation in neurologic disease, the currently used imaging modalities are limited in sensitivity and specificity. Early data suggest that several neurologic conditions have pathologic changes in the retinal nerve fiber layer of the eye, creating a potential surrogate marker for neurodegeneration ...
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    19. Evaluating loss of visual function in multiple sclerosis as measured by low-contrast letter acuity

      Evaluating loss of visual function in multiple sclerosis as measured by low-contrast letter acuity
      Background: Disturbances in visual function are common in patients with multiple sclerosis (MS) and are often accompanied by substantial impairments in daily functioning and quality of life. Lesions associated with these impairments frequently involve the afferent visual pathway. Expert Clinical Opinion: Because these impairments are often not readily apparent on commonly used high-contrast acuity tests, low-contrast charts (e.g., low-contrast Sloan letter charts) have gained validity in the assessment of visual dysfunction in patients with MS. Decrements in low-contrast letter acuity are associated with MS and correlate with increasing disability, MRI abnormalities, and reduced retinal nerve fiber layer (RNFL) thickness ...
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    20. 3D Eye Imaging Enters Neurology Offices

      3D Eye Imaging Enters Neurology Offices

      HEIDELBERG, Germany--(BUSINESS WIRE)--Heidelberg Engineering is introducing SPECTRALIS®, an office-based imaging device for tracking and measuring axonal change, at the 2010 meeting of the American Academy of Neurology in Toronto. The SPECTRALIS Tracking Laser Tomographer uses its on-board Nsite Axonal Analytics™ to track and measure axonal changes within the retinal nerve fiber layer (RNFL) by capturing high resolution cross-sectional images of the eye. “Even though SPECTRALIS offers 100 times higher resolution than an MRI, we don't expect our instrument to replace the role of MRI neurologists” .Numerous peer-reviewed clinical studies have been published in the last several years ...

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    21. Time domain and spectral domain optical coherence tomography in multiple sclerosis: A comparative cross-sectional study

      Conventional time domain optical coherence tomography has been established for the in vivo assessment of retinal axonal loss in multiple sclerosis. The innovative spectral domain imaging is superior to the conventional technique with respect to data acquisition speed, resolution and reproducibility. However, until now comparability of the two techniques has not been investigated in multiple sclerosis. In this study involving 55 multiple sclerosis patients, data obtained using both techniques (Stratus time domain optical coherence tomography and Cirrus spectral domain optical coherence tomography, Carl Zeiss Meditec) showed an excellent correlation (Pearson’s r = 0.926, p < 0.001). However, owing to ...
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    22. Five Advances in Research and Drug Development for MS

      Optical Coherence Tomography (OCT) - for many people the first signs of MS involve blurred version as caused by optic neuritis. It appears as if the very sensitive nerves in the back of the eye tend to be a vulnerable area for the onset of MS-related damage. OCT provides a sensitive, quantitative and easy way to measure the health of nerve fibers in the back of the eye. OCT holds the potential to assess the existence of nerve-related damage possibly before any other symptoms of MS have developed. As such, the possibility exists to allow earlier medical or treatment intervention before ...
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