Category: Neurology

Objective: To compare retinal nerve fiber layer (RNFL) and macular thickness measurements in patients with multiple sclerosis (MS) and neuromyelitis optica (NMO) with or without history of optic neuritis and in controls using Fourier-domain (FD) optical coherence tomography (OCT). Methods: Patients with MS (n=60), NMO (n=33), longitudinal extensive transverse myelitis (LETM) (n=28) and healthy controls (n=41) were submitted to ophthalmic examination, including automated perimetry, and to FD-OCT RNFL and macular thickness measurements. Five groups of eyes were compared: MS with or without previous optic neuritis, NMO, LETM and controls. Correlation between OCT and visual field (VF ...

Objective To evaluate 3D spectral domain optical coherence tomography (SDOCT) volume scans as a tool for quantification of optic nerve head (ONH) volume as a potential marker for treatment effectiveness and disease progression in idiopathic intracranial hypertension (IIH). Design and Patients Cross-sectional pilot trial comparing 19 IIH patients and controls matched for gender, age and body mass index. Each participant underwent SDOCT. A custom segmentation algorithm was developed to quantify ONH volume (ONHV) and height (ONHH) in 3D volume scans. Results Whereas peripapillary retinal nerve fiber layer thickness did not show differences between controls and IIH patients, the newly developed ...

Recent studies have shown that people with multiple sclerosis (MS) who also have diseases related to vascular health such as high cholesterol, high blood pressure, diabetes, cardiovascular disease, and others, may end up more disabled than people with MS who don't have those diseases. This has led to a growing interest in the role of vascular diseases in MS since they may provide another avenue of MS treatment. Some also think that vascular disease may even be a cause of MS. The back of the eye, the retina, is well-suited to studying vascular diseases as blood vessels can be ...

We present spectral domain polarization-sensitive optical coherence tomography (SD PS-OCT) imaging of peripheral nerves. Structural and polarization-sensitive OCT imaging of uninjured rat sciatic nerves was evaluated both qualitatively and quantitatively. OCT and its functional extension, PS-OCT, were used to image sciatic nerve structure with clear delineation of the nerve boundaries to muscle and adipose tissues. A long-known optical effect, bands of Fontana, was also observed. Postprocessing analysis of these images provided significant quantitative information, such as epineurium thickness, estimates of extinction coefficient and birefringence of nerve and muscle tissue, frequency of bands of Fontana at different stretch levels of nerve ...

Background/Objective Parkinson's disease (PD) and the atypical parkinsonian syndromes multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are movement disorders associated with degeneration of the central nervous system. Degeneration of the retina has not been systematically compared in these diseases. Methods This cross-sectional study used spectral-domain optical coherence tomography with manual segmentation to measure the peripapillar nerve fiber layer, the macular thickness, and the thickness of all retinal layers in foveal scans of 40 patients with PD, 19 with MSA, 10 with CBS, 15 with PSP, and 35 age- and sex-matched controls. Results The ...

Speckle contrast based optical coherence angiography (OCA) and optical coherence Doppler tomography (ODT) have been applied to image cerebral blood flow previously. However, the contrast mechanisms of these two methods are not fully studied. Here, we present both flow phantom and in vivo animal experiments using ultrahigh-resolution OCA (μOCA) and ODT (μODT) to investigate the flow sensitivity differences between these two methods. Our results show that the high sensitivity of μOCA for visualizing minute vasculature (e.g., slow capillary beds) is due to the enhancement by random Brownian motion of scatterers (e.g., red and white blood cells) within the ...

Background: To assess the efficacy of quantitative analysis of the optic nerve head and peripapillary retinal nerve fiber layer (RNFL) with the spectral-domain optical coherence tomography (SD-OCT) in differentiating optic disc edema (ODE) from optic nerve head drusen (ONHD). Methods: Prospective clinical study. Twenty-five eyes of 25 ODE patients (group 1), 25 eyes of 25 ONHD patients (group 2), and 25 eyes of 25 healthy subjects were included. The thickness of the peripapillary RNFL, the thickness of the subretinal hyporeflective space (SHYPS), the area of the SHYPS, the horizontal length of the optic nerve head, and the angle between the ...

Purpose To calculate and validate a linear discriminant function (LDF) for spectral-domain optical coherence tomography (OCT) to improve the diagnostic ability of retinal nerve fiber layer (RNFL) thickness parameters for the detection of multiple sclerosis (MS). Design Observational cross-sectional study. Participants Patients with multiple sclerosis (n = 115) and age-matched healthy subjects (n = 115) were enrolled in the study. Methods The Spectralis OCT system (Heidelberg Engineering, Heidelberg, Germany) was used to obtain the circumpapillary RNFL thickness in both eyes of each participant. Main Outcome Measures A validating set including 60% of the study subjects (69 healthy individuals and 69 patients with ...

In a previous study, we reported measurements of three-dimensional (3D) optical coherence tomography (OCT) images through a thinned skull by reducing temperatures from 28 °C to 18 °C in vivo in the rat brain to show negative correlation coefficients (CCs) between ratios of signal intensity (RSI) and temperature for applications to monitoring brain viability. In this study, using the same OCT system, we measured 3D OCT images of the rat brain by periodically changing tissue temperatures from 20 °C to 32 °C in vivo. In the evaluation of CCs among RSI, temperature, and heart rate, the largest number of periods ...

Background Optical coherence tomography (OCT) is a simple, high-resolution technique to quantify the thickness of retinal nerve fiber layer (RNFL), which provides an indirect measurement of axonal damage in multiple sclerosis (MS). This study aimed to evaluate RNFL thickness in patients at presentation with clinically isolated syndromes (CIS) suggestive of MS. Methodology This was a cross-sectional study. Twenty-four patients with CIS suggestive of MS (8 optic neuritis [ON], 6 spinal cord syndromes, 5 brainstem symptoms and 5 with sensory and other syndromes) were prospectively studied. The main outcome evaluated was RNFL thickness at CIS onset. Secondary objectives were to study ...

Patients with idiopathic intracranial hypertension (IIH) often present papilledema at the optic nerve head (ONH), associated with visual field losses. In order to quantify the edema, the computation of its volume is needed. Optical coherence tomography (OCT) is a noninvasive method for spatial imaging of retinal layer composition. However, current algorithms fail to segment the ONH in IIH patients satisfactorily. We developed an automatic method for segmenting the retinal pigment epithelium layer (RPE) from spatial high-resolution OCT ONH scans with robust performance in IIH patients. Using a hypothetical extension of the RPE through the ONH we were able to compute ...

Macular optical coherence tomography (OCT) segmentation, enabling quantification of retinal axonal and neuronal subpopulations, may help elucidate the neuroretinal pathobiology of multiple sclerosis (MS). This study aimed to determine the agreement, reproducibility, and visual correlations of retinal layer thicknesses measured by different OCT segmentation techniques, on two spectral-domain OCT devices. Macular scans of 52 MS patients and 30 healthy controls from Spectralis OCT and Cirrus HD-OCT were segmented using fully manual (Spectralis), computer-aided manual (Spectralis and Cirrus), and fully automated (Cirrus) segmentation techniques. Letter acuity was recorded. Bland-Altman analyses revealed low mean differences across OCT segmentation techniques on both devices ...

Multiple sclerosis (MS) is a common neurological disease in North America and Europe. Although most patients develop major locomotor disability over the course of 15–20 years, in approximately one-third of patients the long-term course is favorable, with minimal disability. Although current disease-modifying treatments reduce the relapse rate, their long-term effects are uncertain. MS treatment trials are challenging because of the variable clinical course and typically slow evolution of the disease. Magnetic resonance imaging (MRI) is sensitive in monitoring MS pathology and facilitates evaluation of potential new treatments. MRI measurements of lesion activity have identified new immunomodulatory treatments for preventing ...

Background: Optical coherence tomography can be used to assess retinal degeneration in multiple sclerosis (MS). Thinning of the retinal nerve fibre layer and macular thickness have been well characterized, but newer devices allow quantification of all retinal layers. Objectives: The objective of this study was to evaluate the thickness of the paramacular retina, peripapillary retinal nerve fibre layer, and deeper paramacular layers in MS patient subgroups, using state-of-the-art optical coherence tomography. Methods: Using a Heidelberg Engineering Spectralis device, we performed paramacular volumetric retinal scans and circular peripapillary fibre-layer scans, manually segmenting different retinal layers into single horizontal foveal scans in ...

Multiple sclerosis (MS) is an autoimmune, inflammatory, neurodegenerative, demyelinating disease of the central nervous system, predominantly involving myelinated neurons of the brain, spinal cord, and optic nerve. Optic neuritis is frequently associated with MS and often precedes other neurologic deficits associated with MS. A large number of patients experience visual defects and have abnormalities concomitant with neurologic abnormalities. Transgenic mice manifesting spontaneous neurologic and ocular disease are unique models that have revolutionized the study of MS. Spontaneous experimental autoimmune encephalomyelitis (sEAE) presents with spontaneous onset of demyelination, without the need of an injectable immunogen. This review highlights the various models ...