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1.
Brain ; 147(1): 267-280, 2024 01 04.
Article in English | MEDLINE | ID: mdl-38059801

ABSTRACT

The heterogenous aetiology of Parkinson's disease is increasingly recognized; both mitochondrial and lysosomal dysfunction have been implicated. Powerful, clinically applicable tools are required to enable mechanistic stratification for future precision medicine approaches. The aim of this study was to characterize bioenergetic dysfunction in Parkinson's disease by applying a multimodal approach, combining standardized clinical assessment with midbrain and putaminal 31-phosphorus magnetic resonance spectroscopy (31P-MRS) and deep phenotyping of mitochondrial and lysosomal function in peripheral tissue in patients with recent-onset Parkinson's disease and control subjects. Sixty participants (35 patients with Parkinson's disease and 25 healthy controls) underwent 31P-MRS for quantification of energy-rich metabolites [ATP, inorganic phosphate (Pi) and phosphocreatine] in putamen and midbrain. In parallel, skin biopsies were obtained from all research participants to establish fibroblast cell lines for subsequent quantification of total intracellular ATP and mitochondrial membrane potential (MMP) as well as mitochondrial and lysosomal morphology, using high content live cell imaging. Lower MMP correlated with higher intracellular ATP (r = -0.55, P = 0.0016), higher mitochondrial counts (r = -0.72, P < 0.0001) and higher lysosomal counts (r = -0.62, P = 0.0002) in Parkinson's disease patient-derived fibroblasts only, consistent with impaired mitophagy and mitochondrial uncoupling. 31P-MRS-derived posterior putaminal Pi/ATP ratio variance was considerably greater in Parkinson's disease than in healthy controls (F-tests, P = 0.0036). Furthermore, elevated 31P-MRS-derived putaminal, but not midbrain Pi/ATP ratios (indicative of impaired oxidative phosphorylation) correlated with both greater mitochondrial (r = 0.37, P = 0.0319) and lysosomal counts (r = 0.48, P = 0.0044) as well as lower MMP in both short (r = -0.52, P = 0.0016) and long (r = -0.47, P = 0.0052) mitochondria in Parkinson's disease. Higher 31P-MRS midbrain phosphocreatine correlated with greater risk of rapid disease progression (r = 0.47, P = 0.0384). Our data suggest that impaired oxidative phosphorylation in the striatal dopaminergic nerve terminals exceeds mitochondrial dysfunction in the midbrain of patients with early Parkinson's disease. Our data further support the hypothesis of a prominent link between impaired mitophagy and impaired striatal energy homeostasis as a key event in early Parkinson's disease.


Subject(s)
Parkinson Disease , Humans , Phosphocreatine/metabolism , Mitochondria/metabolism , Corpus Striatum/metabolism , Adenosine Triphosphate/metabolism
2.
Mov Disord ; 38(8): 1493-1502, 2023 08.
Article in English | MEDLINE | ID: mdl-37246815

ABSTRACT

BACKGROUND: Rescue of mitochondrial function is a promising neuroprotective strategy for Parkinson's disease (PD). Ursodeoxycholic acid (UDCA) has shown considerable promise as a mitochondrial rescue agent across a range of preclinical in vitro and in vivo models of PD. OBJECTIVES: To investigate the safety and tolerability of high-dose UDCA in PD and determine midbrain target engagement. METHODS: The UP (UDCA in PD) study was a phase II, randomized, double-blind, placebo-controlled trial of UDCA (30 mg/kg daily, 2:1 randomization UDCA vs. placebo) in 30 participants with PD for 48 weeks. The primary outcome was safety and tolerability. Secondary outcomes included 31-phosphorus magnetic resonance spectroscopy (31 P-MRS) to explore target engagement of UDCA in PD midbrain and assessment of motor progression, applying both the Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS-III) and objective, motion sensor-based quantification of gait impairment. RESULTS: UDCA was safe and well tolerated, and only mild transient gastrointestinal adverse events were more frequent in the UDCA treatment group. Midbrain 31 P-MRS demonstrated an increase in both Gibbs free energy and inorganic phosphate levels in the UDCA treatment group compared to placebo, reflecting improved ATP hydrolysis. Sensor-based gait analysis indicated a possible improvement of cadence (steps per minute) and other gait parameters in the UDCA group compared to placebo. In contrast, subjective assessment applying the MDS-UPDRS-III failed to detect a difference between treatment groups. CONCLUSIONS: High-dose UDCA is safe and well tolerated in early PD. Larger trials are needed to further evaluate the disease-modifying effect of UDCA in PD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Subject(s)
Parkinson Disease , Humans , Parkinson Disease/complications , Ursodeoxycholic Acid/therapeutic use , Double-Blind Method
3.
Appl Opt ; 62(30): 8150-8158, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-38038112

ABSTRACT

Planar and volumetric density measurements in the wake region behind a mounted hemispherical turret are obtained using laser Rayleigh scattering. The measurements are conducted in a Mach 2 wind tunnel facility at the Kirtland Air Force Base. Quantitative measurements of density and contour plots with lines of constant density are computed, thus enabling visualization of the turret wake's fluid dynamics. A new, to the best of our knowledge, laser diagnostic methodology and configuration for capturing laser images is also presented. This methodology enables further suppression of background light scattering. Multi-dimensional single-shot and time-average measurements are recorded at multiple axial locations behind the turret. The images acquired reveal turbulent regions of the wake flow, and a discussion of the observed phenomena is presented.

4.
J Magn Reson Imaging ; 55(2): 435-442, 2022 02.
Article in English | MEDLINE | ID: mdl-34322948

ABSTRACT

BACKGROUND: Glutathione (GSH) is an important brain antioxidant and a number of studies have reported its measurement by edited and nonedited localized 1 H spectroscopy techniques within a range of applications in healthy volunteers and disease states. Good test-retest reproducibility is key when assessing the efficacy of treatments aimed at modulating GSH levels within the central nervous system or when noninvasively assessing changes in GSH content over time. PURPOSE: To evaluate the intraday (in vitro and in vivo) and 1-month apart (in vivo) test-retest reproducibility of GSH measurements from GSH-edited MEGA-PRESS acquisitions at 3 T in a phantom and in the brain of a cohort of middle-aged and older healthy volunteers. STUDY TYPE: Prospective. SUBJECTS/PHANTOMS: A phantom containing physiological concentrations of GSH and metabolites with overlapping spectral signatures and 10 healthy volunteers (4 F, 6 M, 55 ± 14 years old). FIELD STRENGTH/SEQUENCE: GSH-edited spectra were acquired at 3 T using the MEGA-PRESS sequence. ASSESSMENT: The phantom was scanned twice and the healthy subjects were scanned three times (on two separate days, 1 month apart). GSH was quantified from each acquisition, with the in vivo voxels placed at the primary motor cortex (PMC) and the occipital cortex (OCC). STATISTICAL TESTS: Mean coefficients of variation (CV) were used to assess short-term (in vitro and in vivo) and longer-term (in vivo) test-retest reproducibility. RESULTS: In vitro, the CV was 2.3%. In vivo, the mean intraday CV was 3.3% in the PMC and 2.4% in the OCC, while the CVs at 1 month apart were 4.6% in the PMC and 7.8% in the OCC. DATA CONCLUSION: GSH-edited MEGA-PRESS spectroscopy allows measurement of GSH with excellent precision. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.


Subject(s)
Motor Cortex , Adult , Aged , Brain , Glutathione , Humans , Middle Aged , Occipital Lobe/diagnostic imaging , Prospective Studies , Reproducibility of Results
5.
Muscle Nerve ; 65(2): 203-210, 2022 02.
Article in English | MEDLINE | ID: mdl-34687220

ABSTRACT

INTRODUCTION/AIMS: The motor unit size index (MUSIX) may provide insight into reinnervation patterns in diseases such as amyotrophic lateral sclerosis (ALS). However, it is not known whether MUSIX detects clinically relevant changes in reinnervation, or if all muscles manifest changes in MUSIX in response to reinnervation after motor unit loss. METHODS: Fifty-seven patients with ALS were assessed at 3-month intervals for 12 months in four centers. Muscles examined were abductor pollicis brevis, abductor digiti minimi, biceps brachii, and tibialis anterior. Results were split into two groups: muscles with increases in MUSIX and those without increases. Longitudinal changes in MUSIX, motor unit number index (MUNIX), compound muscle action potential amplitude, and Medical Research Council strength score were investigated. RESULTS: One hundred thirty-three muscles were examined. Fifty-nine percent of the muscles exhibited an increase in MUSIX during the study. Muscles with MUSIX increases lost more motor units (58% decline in MUNIX at 12 months, P < .001) than muscles that did not increase MUSIX (34.6% decline in MUNIX at 12 months, P < .001). However, longitudinal changes in muscle strength were similar. When motor unit loss was similar, the absence of a MUSIX increase was associated with a significantly greater loss of muscle strength (P = .002). DISCUSSION: MUSIX increases are associated with greater motor unit loss but relative preservation of muscle strength. Thus, MUSIX appears to be measuring a clinically relevant response that can provide a quantitative outcome measure of reinnervation in clinical trials. Furthermore, MUSIX suggests that reinnervation may play a major role in determining the progression of weakness.


Subject(s)
Amyotrophic Lateral Sclerosis , Electromyography/methods , Humans , Motor Neurons/physiology , Muscle Strength , Muscle, Skeletal/physiology
6.
Eur J Neurol ; 29(8): 2163-2172, 2022 08.
Article in English | MEDLINE | ID: mdl-35460319

ABSTRACT

BACKGROUND AND PURPOSE: Health risks associated with SARS-CoV-2 infection are undisputed. Moreover, the capability of vaccination to prevent symptomatic, severe, and fatal COVID-19 is recognized. There is also early evidence that vaccination can reduce the chance for long COVID-19. Nonetheless, the willingness to get vaccinated and receive booster shots remains subpar among people with neurologic disorders. Vaccine scepticism not only jeopardizes collective efforts to end the COVID-19 pandemic but puts individual lives at risk, as some chronic neurologic diseases are associated with a higher risk for an unfavorable COVID-19 course. METHODS: In this position paper, the NeuroCOVID-19 Task Force of the European Academy of Neurology (EAN) summarizes the current knowledge on the prognosis of COVID-19 among patients with neurologic disease, elucidates potential barriers to vaccination coverage, and formulates strategies to overcome vaccination hesitancy. A survey among the Task Force members on the phenomenon of vaccination hesitancy among people with neurologic disease supports the lines of argumentation. RESULTS: The study revealed that people with multiple sclerosis and other nervous system autoimmune disorders are most skeptical of SARS-CoV-2 vaccination. The prevailing concerns included the chance of worsening the pre-existing neurological condition, vaccination-related adverse events, and drug interaction. CONCLUSIONS: The EAN NeuroCOVID-19 Task Force reinforces the key role of neurologists as advocates of COVID-19 vaccination. Neurologists need to argue in the interest of their patients about the overwhelming individual and global benefits of COVID-19 vaccination. Moreover, they need to keep on eye on this vulnerable patient group, its concerns, and the emergence of potential safety signals.


Subject(s)
COVID-19 Vaccines , COVID-19 , Nervous System Diseases , Vaccination Hesitancy , COVID-19/complications , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , Humans , Pandemics , SARS-CoV-2 , Vaccination/psychology , Post-Acute COVID-19 Syndrome
7.
J Neurol Neurosurg Psychiatry ; 92(5): 510-518, 2021 05.
Article in English | MEDLINE | ID: mdl-33589474

ABSTRACT

OBJECTIVE: The clinical utility of routine genetic sequencing in amyotrophic lateral sclerosis (ALS) is uncertain. Our aim was to determine whether routine targeted sequencing of 44 ALS-relevant genes would have a significant impact on disease subclassification and clinical care. METHODS: We performed targeted sequencing of a 44-gene panel in a prospective case series of 100 patients with ALS recruited consecutively from the Sheffield Motor Neuron Disorders Clinic, UK. All participants were diagnosed with ALS by a specialist Consultant Neurologist. 7/100 patients had familial ALS, but the majority were apparently sporadic cases. RESULTS: 21% of patients with ALS carried a confirmed pathogenic or likely pathogenic mutation, of whom 93% had no family history of ALS. 15% met the inclusion criteria for a current ALS genetic-therapy trial. 5/21 patients with a pathogenic mutation had an additional variant of uncertain significance (VUS). An additional 21% of patients with ALS carried a VUS in an ALS-associated gene. Overall, 13% of patients carried more than one genetic variant (pathogenic or VUS). Patients with ALS carrying two variants developed disease at a significantly earlier age compared with patients with a single variant (median age of onset=56 vs 60 years, p=0.0074). CONCLUSIONS: Routine screening for ALS-associated pathogenic mutations in a specialised ALS referral clinic will impact clinical care in 21% of cases. An additional 21% of patients have variants in the ALS gene panel currently of unconfirmed significance after removing non-specific or predicted benign variants. Overall, variants within known ALS-linked genes are of potential clinical importance in 42% of patients.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Genetic Testing , Mutation , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult
8.
Eur J Neurol ; 28(11): 3849-3855, 2021 11.
Article in English | MEDLINE | ID: mdl-33460486

ABSTRACT

Coronavirus disease 2019 (COVID-19), a multi-organ disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), continues to challenge health and care systems around the globe. The pandemic has disrupted acute neurology services and routine patient care and has impacted the clinical course in patients with chronic neurological disease. COVID-19 appears to have exposed inequalities of societies and healthcare systems and had a disproportionate impact on already vulnerable communities. The next challenge will be to set up initiatives to stop disparities in all aspects related to COVID-19. From the medical perspective, there is a need to consider inequalities in prevention, treatment and long-term consequences. Some of the issues of direct relevance to neurologists are summarised. With this appraisal, the European Academy of Neurology NeuroCOVID-19 Task Force intends to raise awareness of the potential impact of COVID-19 on inequalities in healthcare and calls for action to prevent disparity at individual, national and supranational levels.


Subject(s)
COVID-19 , Neurology , Humans , Pandemics , SARS-CoV-2 , Vaccination
9.
Brain ; 143(12): 3603-3618, 2020 12 01.
Article in English | MEDLINE | ID: mdl-33439988

ABSTRACT

Mitochondrial dysfunction is postulated to be central to amyotrophic lateral sclerosis (ALS) pathophysiology. Evidence comes primarily from disease models and conclusive data to support bioenergetic dysfunction in vivo in patients is currently lacking. This study is the first to assess mitochondrial dysfunction in brain and muscle in individuals living with ALS using 31P-magnetic resonance spectroscopy (MRS), the modality of choice to assess energy metabolism in vivo. We recruited 20 patients and 10 healthy age and gender-matched control subjects in this cross-sectional clinico-radiological study. 31P-MRS was acquired from cerebral motor regions and from tibialis anterior during rest and exercise. Bioenergetic parameter estimates were derived including: ATP, phosphocreatine, inorganic phosphate, adenosine diphosphate, Gibbs free energy of ATP hydrolysis (ΔGATP), phosphomonoesters, phosphodiesters, pH, free magnesium concentration, and muscle dynamic recovery constants. Linear regression was used to test for associations between brain data and clinical parameters (revised amyotrophic functional rating scale, slow vital capacity, and upper motor neuron score) and between muscle data and clinico-neurophysiological measures (motor unit number and size indices, force of contraction, and speed of walking). Evidence for primary dysfunction of mitochondrial oxidative phosphorylation was detected in the brainstem where ΔGATP and phosphocreatine were reduced. Alterations were also detected in skeletal muscle in patients where resting inorganic phosphate, pH, and phosphomonoesters were increased, whereas resting ΔGATP, magnesium, and dynamic phosphocreatine to inorganic phosphate recovery were decreased. Phosphocreatine in brainstem correlated with respiratory dysfunction and disability; in muscle, energy metabolites correlated with motor unit number index, muscle power, and speed of walking. This study provides in vivo evidence for bioenergetic dysfunction in ALS in brain and skeletal muscle, which appears clinically and electrophysiologically relevant. 31P-MRS represents a promising technique to assess the pathophysiology of mitochondrial function in vivo in ALS and a potential tool for future clinical trials targeting bioenergetic dysfunction.


Subject(s)
Mitochondria/chemistry , Mitochondrial Diseases/metabolism , Adenosine Triphosphate/metabolism , Aged , Amyotrophic Lateral Sclerosis/metabolism , Brain Chemistry , Cross-Sectional Studies , Energy Metabolism , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Motor Neurons/metabolism , Motor Neurons/pathology , Muscle Contraction , Muscle Strength , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Oxidative Phosphorylation , Phosphocreatine/metabolism , Walking
10.
Curr Opin Ophthalmol ; 31(5): 423-426, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32740065

ABSTRACT

PURPOSE OF REVIEW: The aim of this study was to report characteristics of patients presenting with serious ocular injuries during the COVID-19 stay-at-home orders. RECENT FINDINGS: Of 1058 patients presenting for emergency evaluation during the stay-at-home order, 62 (5.9%) patients [mean (SD) age, 41.1 (19.2) years; 19 (31%) women; 31 (50%) white] presented with severe ocular trauma. The daily mean (SD) number of patients who presented for emergency evaluation decreased from 49.0 (9) to 36.4 (6) during the quarantine (P < 0.001). Patients presenting during the stay-at-home order were less likely to have health insurance [odds ratio (OR), 0.33; 95% confidence interval (95% CI), 0.13-0.90, P = 0.024], more likely to have a delayed presentation (difference, 22.7 h, 95% CI, 5.8-39.5, P < 0.001, more likely to travel farther to seek emergency care (difference, 10.4 miles, 95% CI, 2.6-18.2, P < 0.001) and more likely to have an injury occur at home (OR, 22.8; 95% CI, 9.6-54.2, P < 0.001). Of injuries occurring at home, there was a significant increase in injuries arising from home improvement projects during the stay-at-home order (28 vs. 0%, P = 0.02). SUMMARY: During the COVID-19 pandemic, patients with ocular trauma were more likely to have injuries sustained at home and have additional barriers to care. These changes underscore a need for targeted interventions to optimize emergent eye care during a pandemic.


Subject(s)
Betacoronavirus , Coronavirus Infections/epidemiology , Emergency Service, Hospital/statistics & numerical data , Eye Injuries/epidemiology , Pneumonia, Viral/epidemiology , Quarantine , Adult , COVID-19 , Delivery of Health Care , Eye Injuries/diagnosis , Eye Injuries/prevention & control , Female , Humans , Incidence , Male , Middle Aged , Odds Ratio , Pandemics , Philadelphia/epidemiology , Retrospective Studies , SARS-CoV-2 , Young Adult
11.
Orbit ; 38(1): 84-86, 2019 Feb.
Article in English | MEDLINE | ID: mdl-29565715

ABSTRACT

Adnexal and periocular involvement in Neisseria gonorrhoeae (NG) infection is rare. This report describes the case of a patient with a delayed diagnosis of gonococcal dacryoadenitis with contiguous conjunctivitis and corneal involvement. She underwent extensive inpatient laboratory and infectious workup but rapidly progressed to corneal perforation requiring emergent penetrating keratoplasty prior to a positive culture confirming the diagnosis. To date, this is the first reported case of ophthalmologic NG infection with associated conjunctivitis, dacryoadenitis, and corneal perforation.


Subject(s)
Conjunctivitis, Bacterial/microbiology , Corneal Perforation/microbiology , Dacryocystitis/microbiology , Eye Infections, Bacterial/microbiology , Gonorrhea/microbiology , Neisseria gonorrhoeae/isolation & purification , Anti-Bacterial Agents/therapeutic use , Conjunctivitis, Bacterial/diagnosis , Conjunctivitis, Bacterial/surgery , Corneal Perforation/diagnosis , Corneal Perforation/surgery , Dacryocystitis/diagnosis , Dacryocystitis/surgery , Eye Infections, Bacterial/diagnosis , Eye Infections, Bacterial/surgery , Female , Gonorrhea/diagnosis , Gonorrhea/surgery , Humans , Keratoplasty, Penetrating , Tomography, X-Ray Computed , Young Adult
12.
J Neurol Neurosurg Psychiatry ; 89(3): 248-255, 2018 03.
Article in English | MEDLINE | ID: mdl-29089397

ABSTRACT

OBJECTIVE: To assess clinical, electrophysiological and whole-body muscle MRI measurements of progression in patients with motor neuron disease (MND), as tools for future clinical trials, and to probe pathophysiological mechanisms in vivo. METHODS: A prospective, longitudinal, observational, clinicoelectrophysiological and radiological cohort study was performed. Twenty-nine patients with MND and 22 age-matched and gender-matched healthy controls were assessed with clinical measures, electrophysiological motor unit number index (MUNIX) and T2-weighted whole-body muscle MRI, at first clinical presentation and 4 months later. Between-group differences and associations were assessed using age-adjusted and gender-adjusted multivariable regression models. Within-subject longitudinal changes were assessed using paired t-tests. Patterns of disease spread were modelled using mixed-effects multivariable regression, assessing associations between muscle relative T2 signal and anatomical adjacency to site of clinical onset. RESULTS: Patients with MND had 30% higher relative T2 muscle signal than controls at baseline (all regions mean, 95% CI 15% to 45%, p<0.001). Higher T2 signal was associated with greater overall disability (coefficient -0.009, 95% CI -0.017 to -0.001, p=0.023) and with clinical weakness and lower MUNIX in multiple individual muscles. Relative T2 signal in bilateral tibialis anterior increased over 4 months in patients with MND (right: 10.2%, 95% CI 2.0% to 18.4%, p=0.017; left: 14.1%, 95% CI 3.4% to 24.9%, p=0.013). Anatomically, contiguous disease spread on MRI was not apparent in this model. CONCLUSIONS: Whole-body muscle MRI offers a new approach to objective assessment of denervation over short timescales in MND and enables investigation of patterns of disease spread in vivo. Muscles inaccessible to conventional clinical and electrophysiological assessment may be investigated using this methodology.


Subject(s)
Action Potentials , Amyotrophic Lateral Sclerosis/diagnostic imaging , Muscle, Skeletal/diagnostic imaging , Muscular Atrophy, Spinal/diagnostic imaging , Adult , Aged , Amyotrophic Lateral Sclerosis/physiopathology , Case-Control Studies , Cohort Studies , Electromyography , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Middle Aged , Motor Neuron Disease/diagnostic imaging , Motor Neuron Disease/physiopathology , Muscle, Skeletal/innervation , Muscle, Skeletal/physiopathology , Muscular Atrophy, Spinal/physiopathology , Prospective Studies , Whole Body Imaging
13.
Curr Opin Neurol ; 30(1): 61-66, 2017 02.
Article in English | MEDLINE | ID: mdl-27906756

ABSTRACT

PURPOSE OF REVIEW: Acute optic neuritis is a common clinical problem, requiring a structured assessment to guide management and prevent visual loss. The optic nerve is the most accessible part of the central nervous system, so optic neuritis also represents an important paradigm to help decipher mechanisms of damage and recovery in the central nervous system. Important developments include the advent of optical coherence tomography as a biomarker of central nervous system axonal loss, the discovery of new pathological antibodies, notably against aquaporin-4 and, more recently, myelin oligodendrocyte protein, and emerging evidence for sodium channel blockade as a novel therapeutic approach to address energy failure in neuroinflammatory disease. RECENT FINDINGS: We will present a practical approach to assessment of optic neuritis, highlighting the role of optical coherence tomography, when to test for new antibodies and the results of recent trials of sodium channel blockers. SUMMARY: Optic neuritis remains a clinical diagnosis; increasingly optical coherence tomography is a key ancillary investigation. Patients with 'typical' optic neuritis, commonly a first presentation of multiple sclerosis, must be distinguished from 'atypical' optic neuritis, who require testing for new pathological antibodies and require more aggressive-targeted treatment. Sodium channel blockade is an emerging and novel potential therapeutic pathway in neuroinflammatory disease.


Subject(s)
Axons/pathology , Brain/pathology , Optic Nerve/pathology , Optic Neuritis/pathology , Brain/diagnostic imaging , Humans , Optic Nerve/diagnostic imaging , Optic Neuritis/diagnostic imaging , Tomography, Optical Coherence
14.
Brain ; 139(Pt 3): 816-28, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26912640

ABSTRACT

In multiple sclerosis, microstructural damage of normal-appearing brain tissue is an important feature of its pathology. Understanding these mechanisms is vital to help develop neuroprotective strategies. The visual pathway is a key model to study mechanisms of damage and recovery in demyelination. Anterograde trans-synaptic degeneration across the lateral geniculate nuclei has been suggested as a mechanism of tissue damage to explain optic radiation abnormalities seen in association with demyelinating disease and optic neuritis, although evidence for this has relied solely on cross-sectional studies. We therefore aimed to assess: (i) longitudinal changes in the diffusion properties of optic radiations after optic neuritis suggesting trans-synaptic degeneration; (ii) the predictive value of early optic nerve magnetic resonance imaging measures for late optic radiations changes; and (iii) the impact on visual outcome of both optic nerve and brain post-optic neuritis changes. Twenty-eight consecutive patients with acute optic neuritis and eight healthy controls were assessed visually (logMAR, colour vision, and Sloan 1.25%, 5%, 25%) and by magnetic resonance imaging, at baseline, 3, 6, and 12 months. Magnetic resonance imaging sequences performed (and metrics obtained) were: (i) optic nerve fluid-attenuated inversion-recovery (optic nerve cross-sectional area); (ii) optic nerve proton density fast spin-echo (optic nerve proton density-lesion length); (iii) optic nerve post-gadolinium T1-weighted (Gd-enhanced lesion length); and (iv) brain diffusion-weighted imaging (to derive optic radiation fractional anisotropy, radial diffusivity, and axial diffusivity). Mixed-effects and multivariate regression models were performed, adjusting for age, gender, and optic radiation lesion load. These identified changes over time and associations between early optic nerve measures and 1-year global optic radiation/clinical measures. The fractional anisotropy in patients' optic radiations decreased (P = 0.018) and radial diffusivity increased (P = 0.002) over 1 year following optic neuritis, whereas optic radiation measures were unchanged in controls. Also, smaller cross-sectional areas of affected optic nerves at 3 months post-optic neuritis predicted lower fractional anisotropy and higher radial diffusivity at 1 year (P = 0.007) in the optic radiations, whereas none of the inflammatory measures of the optic nerve predicted changes in optic radiations. Finally, greater Gd-enhanced lesion length at baseline and greater optic nerve proton density-lesion length at 1 year were associated with worse visual function at 1 year (P = 0.034 for both). Neither the cross-sectional area of the affected optic nerve after optic neuritis nor the damage in optic radiations was associated with 1-year visual outcome. Our longitudinal study shows that, after optic neuritis, there is progressive damage to the optic radiations, greater in patients with early residual optic nerve atrophy, even after adjusting for optic radiation lesions. These findings provide evidence for trans-synaptic degeneration.


Subject(s)
Optic Neuritis/complications , Optic Neuritis/diagnosis , Retrograde Degeneration/diagnosis , Retrograde Degeneration/etiology , Synapses/pathology , Adult , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Visual Pathways/pathology
15.
J Clin Densitom ; 20(2): 205-215, 2017.
Article in English | MEDLINE | ID: mdl-26710681

ABSTRACT

Age- and disease (osteoporotic fractured and osteoarthritic tissue)-related changes in the distribution of cortical bone were examined, using a multimodality approach, including measurement of local density, geometry and mechanical properties, where changes in these properties can give rise to instability and increasing probability of fracture. In contrast to the majority of previously reported research, this study also focuses on the characteristic non-circular femoral neck cross-sectional geometry and variation in bone mineral density (BMD) around the femoral neck. Twenty-two osteoarthritic and 7 osteoporotic femoral neck slices, collected from elective and trauma-related arthroplasty, and 16 cadaveric donor tissue controls were tested mechanically using Reference Point Indentation (BioDent™, Active Life Technologies®, Santa Barbara, CA) and then scanned with in vitro-based radiography intended to replicate the dual-energy X-ray absorptiometry technique. All parameters were measured regionally around the circumference of the femoral neck, allowing examination of spatial variability within the cortical bone. Fractured tissue was less resistant to indentation in the thinner superolateral segment compared to other segments and other groups. BMD around the fractured femoral necks appeared more consistent than that of nonfractured tissue, where BMD was reduced in the superolateral segment for the other groups. Cortical bone was thin in the superolateral segment for all groups except for the osteoarthritic group, and was thicker in the inferomedial segment for both osteoarthritic and fractured groups, resulting in the largest variation in buckling ratio (ratio of cortical bone diameter to cortical bone thickness) around the femoral neck for the fractured group. With age, healthy controls appeared to have lower inferomedial cortical thickness, whereas no significant differences in Reference Point Indentation measurements and density were observed. The study has highlighted several (both quality- and quantity-related) parameters that may be used to improve prediction of fracture risk.


Subject(s)
Bone Density , Cortical Bone/physiopathology , Femoral Neck Fractures/physiopathology , Femur Neck/physiopathology , Osteoarthritis/physiopathology , Osteoporosis/physiopathology , Absorptiometry, Photon/methods , Adult , Aged , Aged, 80 and over , Biomechanical Phenomena , Compressive Strength , Cortical Bone/diagnostic imaging , Cortical Bone/pathology , Female , Femoral Neck Fractures/diagnostic imaging , Femoral Neck Fractures/pathology , Femur Neck/diagnostic imaging , Femur Neck/pathology , Humans , Male , Middle Aged
16.
Ophthalmic Plast Reconstr Surg ; 33(2): e33-e36, 2017.
Article in English | MEDLINE | ID: mdl-27046037

ABSTRACT

Orbital extension of subgaleal hematoma is rare. This report describes the case of an otherwise healthy 10-year-old girl who developed delayed contralateral proptosis and external ophthalmoplegia after relatively minor right-sided forehead trauma. She was found to have bilateral subgaleal hematomas communicating with a left superior subperiostial orbital hematoma. Over the course of 2 days, she developed an orbital compartment syndrome requiring emergent canthotomy and cantholysis, followed by surgical incision and drainage of her scalp hematoma without orbitotomy. Hematologic work-up revealed heterozygous factor VII deficiency.


Subject(s)
Compartment Syndromes/etiology , Craniocerebral Trauma/complications , Hematoma/etiology , Orbital Diseases/diagnosis , Child , Factor VII Deficiency/complications , Female , Humans
17.
Muscle Nerve ; 54(3): 378-85, 2016 09.
Article in English | MEDLINE | ID: mdl-26821620

ABSTRACT

INTRODUCTION: The contribution of cranial and thoracic region electromyography (EMG) to diagnostic criteria for amyotrophic lateral sclerosis (ALS) has not been evaluated. METHODS: Clinical and EMG data from each craniospinal region were retrospectively assessed in 470 patients; 214 had ALS. Changes to diagnostic classification in Awaji-Shima and revised El Escorial criteria after withdrawal of cranial/thoracic EMG data were ascertained. RESULTS: Sensitivity for lower motor neuron involvement in ALS was highest in the cervical/lumbar regions; specificity was highest in cranial/thoracic regions. Cranial EMG contributed to definite/probable Awaji-Shima categorization in 1.4% of patients. Thoracic EMG made no contribution. For revised El Escorial criteria, cranial and thoracic data reclassified 1% and 5% of patients, respectively. CONCLUSION: Cranial EMG data make small contributions to both criteria, whereas thoracic data contribute only to the revised El Escorial criteria. However, cranial and thoracic region abnormalities are specific in ALS. Consideration should be given to allowing greater diagnostic contribution from thoracic EMG. Muscle Nerve 54: 378-385, 2016.


Subject(s)
Amyotrophic Lateral Sclerosis/diagnosis , Amyotrophic Lateral Sclerosis/physiopathology , Electromyography/methods , Electromyography/standards , Lumbosacral Region/innervation , Skull Base/innervation , Adult , Aged , Aged, 80 and over , England , Female , Humans , Male , Middle Aged , Neurologic Examination , Probability , Retrospective Studies , Sensitivity and Specificity , Young Adult
18.
Am J Obstet Gynecol ; 215(6): 777.e1-777.e4, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27530492

ABSTRACT

BACKGROUND: More than a decade ago, researchers described a survey of Maternal Fetal Medicine fellows that showed that chorionic villus sampling training was limited for Maternal Fetal Medicine fellows in the United States. Prenatal screening and diagnosis have rapidly evolved since then and include the introduction of noninvasive aneuploidy screening that uses cell-free fetal DNA. Yet, chorionic villus sampling remains the only method available for first-trimester genetic diagnosis. OBJECTIVE: This study evaluated the chorionic villus sampling training of Maternal Fetal Medicine fellows with respect to availability, competency standards, and education methods. STUDY DESIGN: In November 2015, an electronic survey was sent to Maternal Fetal Medicine fellows and fellowship directors of accredited Maternal Fetal Medicine fellowship programs in the United States. RESULTS: Fifty-eight percent of fellows (179/310) and 46% of program directors (35/76) responded. Ninety-five percent of Maternal Fetal Medicine fellows think that invasive diagnostic testing is essential to their training; 100% of fellows have amniocentesis training; and 65% have chorionic villus sampling training. The median number of chorionic villus sampling procedures that are expected during a fellowship in those who trained was 10. Eighty-eight percent of fellows and 89% of program directors state that chorionic villus sampling training could be better; 89% of fellows and 97% of directors would like access to simulated models. Barriers to training included lack of patients (71%) and lack of proficient attending supervisors (43%). CONCLUSION: Since the last survey, >10 years ago, chorionic villus sampling training has declined further. A decrease in the number of procedures that are performed is the leading barrier to this training.


Subject(s)
Chorionic Villi Sampling , Obstetrics/education , Perinatology/education , Fellowships and Scholarships , Female , Humans , Pregnancy , Pregnancy Trimester, First , Prenatal Diagnosis , Surveys and Questionnaires , United States
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