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1.
Mult Scler ; : 13524585241280842, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39344166

RESUMO

BACKGROUND: The role of the glymphatic system in multiple sclerosis (MS)-related disability remains underexplored. Diffusion-tensor image analysis along the perivascular space (DTI-ALPS) offers a non-invasive method to assess glymphatic function. OBJECTIVE: To evaluate glymphatic function in MS patients with lower and higher disability. METHODS: This study included 118 MS patients who underwent structural, diffusion-weighted imaging, and clinical assessment. The participants were divided into lower (MS-L, n = 57) and higher disability (MS-H, n = 61) subgroups. Brain parenchymal fraction (BPF), lesion load (LL), and DTI-ALPS index were measured. Subgroup differences and correlations between DTI-ALPS index and other measures were explored. Logistic regression was performed to evaluate BPF, LL, and DTI-ALPS index in classifying lower and higher disability patients. RESULTS: Significant differences in DTI-ALPS index between MS-H and MS-L (d = -0.71, false discovery rate-corrected p-value (p-FDR) = 0.001) were found. The DTI-ALPS index correlated significantly with disease duration (rp = -0.29, p-FDR = 0.002) and EDSS (rsp = -0.35, p-FDR = 0.0002). It also showed significant correlations with BPF and LL. DTI-ALPS index and LL were significant predictors of disability subgroup (DTI-ALPS: odds ratio (OR) = 1.77, p = 0.04, LL: OR = 0.94, p = 0.02). CONCLUSION: Our findings highlight DTI-ALPS index as an imaging biomarker in MS, suggesting the involvement of glymphatic impairment in MS pathology, although further research is needed to elucidate its role in contributing to MS-related disability.

2.
BMC Urol ; 24(1): 20, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273296

RESUMO

BACKGROUND: Multiple Sclerosis (MS) is an often debilitating disease affecting the myelin sheath that encompasses neurons. It can be accompanied by a myriad of pathologies and adverse effects such as neurogenic lower urinary tract dysfunction (NLUTD). Current treatment modalities for resolving NLUTD focus mainly on alleviating symptoms while the source of the discomfort emanates from a disruption in brain to bladder neural circuitry. Here, we leverage functional magnetic resonance imaging (fMRI), repetitive transcranial magnetic stimulation (rTMS) protocols and the brains innate neural plasticity to aid in resolving overactive bladder (OAB) symptoms associated with NLUTD. METHODS: By employing an advanced neuro-navigation technique along with processed fMRI and diffusion tensor imaging data to help locate specific targets in each participant brain, we are able to deliver tailored neuromodulation protocols and affect either an excitatory (20 min @ 10 Hz, applied to the lateral and medial pre-frontal cortex) or inhibitory (20 min @ 1 Hz, applied to the pelvic supplemental motor area) signal on neural circuitry fundamental to the micturition cycle in humans to restore or reroute autonomic and sensorimotor activity between the brain and bladder. Through a regimen of questionnaires, bladder diaries, stimulation sessions and analysis, we aim to gauge rTMS effectiveness in women with clinically stable MS. DISCUSSION: Some limitations do exist with this study. In targeting the MS population, the stochastic nature of MS in general highlights difficulties in recruiting enough participants with similar symptomology to make meaningful comparisons. As well, for this neuromodulatory approach to achieve some rate of success, there must be enough intact white matter in specific brain regions to receive effective stimulation. While we understand that our results will represent only a subset of the MS community, we are confident that we will accomplish our goal of increasing the quality of life for those burdened with MS and NLUTD. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov (NCT06072703), posted on Oct 10, 2023.


Assuntos
Esclerose Múltipla , Bexiga Urinária Hiperativa , Humanos , Feminino , Esclerose Múltipla/complicações , Esclerose Múltipla/terapia , Imagem de Tensor de Difusão , Qualidade de Vida , Encéfalo , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
J Appl Clin Med Phys ; : e14396, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38894588

RESUMO

Noncoplanar arc optimization has been shown to reduce OAR doses in SRS/SRT and has the potential to reduce doses to OARs in SBRT. Extracranial targets have additional considerations, including large OARs and, in the case of the liver, volume constraints on the healthy liver. Considering pathlengths through OARs that encompass target volumes may lead to specific dose reductions as in the encompassing healthy liver tissue. These optimizations must also leverage delivery efficiency and trajectory sampling to ensure ease of clinical translation. The purpose of this research is to generate optimized static-couch arcs that separately consider serial and parallel OARs and arc delivery efficiency, with a trajectory sampling metric, towards the aim of reducing dose to OARs and the surrounding healthy liver tissue. Separate BEV cost maps were created for parallel, and serial OARs by means of a fast ray-triangle intersection algorithm. An additional BEV cost map was created for the liver which, by definition, encompasses the liver tumors. The individual costs of these maps were summed and combined with the sampling metric for 100 000 random combinations of arc trajectories. A search algorithm was applied to find an arc trajectory solution that satisfied BEV cost and sampling optimization, while also ensuring an efficient delivery was possible with a low number of arcs. This method of arc selection was evaluated for 16 liver SBRT patients characterized by small and large target volumes. Comparisons were made with a clinical arc template of coplanar arcs. Dosimetric plan quality was evaluated using published guidelines and metrics from RTOG1112. Four of five plan quality metrics for the liver were significantly reduced when planned with optimized noncoplanar arcs. Median (range) reductions of the volumes receiving 10, 18, and 21 Gy were found of 140.4 (295.8) cc (p = 0.001), 28.2 (230.6) cc (p = 0.002) and 18.5 (155.5) cc (p = 0.04). A significant increase in median (range) dose to the right kidney of 0.2 ± 0.9 Gy (p = 0.03) was also found using optimized noncoplanar arcs, which was below the tolerance of 10 Gy for all cases. The average number of arcs chosen was 4 ± 1. Optimizing serial and parallel OARs separately during static couch noncoplanar arc selection significantly reduced the dose to the liver during SBRT using a moderate number of arcs.

4.
Mult Scler ; 29(10): 1304-1315, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37435828

RESUMO

BACKGROUND: Black and Hispanic patients with multiple sclerosis (MS) have been shown to accumulate greater multiple sclerosis-associated disability (MSAD) than White patients. Disparities in social determinants of health (SDOH) among these groups have also been reported. OBJECTIVE: To determine the extent to which associations of race and ethnicity with MSAD may be attributable to differences in SDOH. METHODS: Retrospective chart analysis of patients at an academic MS center grouped by self-identified Black (n = 95), Hispanic (n = 93), and White (n = 98) race/ethnicity. Individual patient addresses were geocoded and matched with neighborhood-level area deprivation index (ADI) and social vulnerability index (SVI). RESULTS: Average Expanded Disability Status Scale (EDSS) scores at last-recorded evaluations of White patients (1.7 ± 2.0) were significantly lower than Black (2.8 ± 2.4, p = 0.001) and Hispanic (2.6 ± 2.6, p = 0.020) patients. Neither Black race nor Hispanic ethnicity was significantly associated with EDSS in multivariable linear regression models that included individual-level SDOH indicators and either ADI or SVI. CONCLUSION: Black race and Hispanic ethnicity are not significantly associated with EDSS in models that include individual and neighborhood-level SDOH indicators. Further research should elucidate mechanisms by which structural inequities affect MS disease course.


Assuntos
Disparidades nos Níveis de Saúde , Esclerose Múltipla , Determinantes Sociais da Saúde , Humanos , Hispânico ou Latino , Estudos Retrospectivos , Negro ou Afro-Americano , Brancos
5.
Neurourol Urodyn ; 42(1): 239-248, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36321777

RESUMO

OBJECTIVE: To identify specific white matter tracts (WMTs) whose disruption is associated with the severity of neurogenic lower urinary tract dysfunction (NLUTD) in two independent cohorts of women with multiple sclerosis (MS) and NLUTD. METHODS: Cohort 1 consisted of twenty-eight women with MS and NLUTD. The validation cohort consisted of 10 women with MS and NLUTD. Eleven healthy women served as controls. Participants of both MS cohorts had the same inclusion and exclusion criteria. Both MS cohorts and the healthy controls underwent the same clinical assessment and functional MRI (fMRI) protocol, except that the validation MS cohort underwent 7-Tesla fMRI scan. Fifteen WMTs (six coursing to relevant brainstem areas) involved in bladder control were a priori regions of interest (ROI). Spearman's correlation test was performed between each the Fractional Anisotropy (FA) and mean diffusivity (MD) of each WMT and the clinical parameters. RESULTS: Overall, we found a very high degree of overlap (100% of a priori ROI) in the tracts identified by our correlation analysis as having the greatest contribution to NLUTD symptoms in MS women. The right inferior cerebellar peduncle, left posterior limb of internal capsule, and left superior cerebellar peduncle displayed significant associations to the greatest number of clinical parameters. CONCLUSIONS: Our correlation analysis supports the role of specific WMT disruptions in the contribution of symptoms in women with MS and NLUTD, as confirmed in two independent MS cohorts.


Assuntos
Esclerose Múltipla , Substância Branca , Humanos , Feminino , Substância Branca/diagnóstico por imagem , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética
6.
BMC Med Inform Decis Mak ; 23(1): 255, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946182

RESUMO

Multiple Sclerosis (MS) is a chronic disease developed in the human brain and spinal cord, which can cause permanent damage or deterioration of the nerves. The severity of MS disease is monitored by the Expanded Disability Status Scale, composed of several functional sub-scores. Early and accurate classification of MS disease severity is critical for slowing down or preventing disease progression via applying early therapeutic intervention strategies. Recent advances in deep learning and the wide use of Electronic Health Records (EHR) create opportunities to apply data-driven and predictive modeling tools for this goal. Previous studies focusing on using single-modal machine learning and deep learning algorithms were limited in terms of prediction accuracy due to data insufficiency or model simplicity. In this paper, we proposed the idea of using patients' multimodal longitudinal and longitudinal EHR data to predict multiple sclerosis disease severity in the future. Our contribution has two main facets. First, we describe a pioneering effort to integrate structured EHR data, neuroimaging data and clinical notes to build a multi-modal deep learning framework to predict patient's MS severity. The proposed pipeline demonstrates up to 19% increase in terms of the area under the Area Under the Receiver Operating Characteristic curve (AUROC) compared to models using single-modal data. Second, the study also provides valuable insights regarding the amount useful signal embedded in each data modality with respect to MS disease prediction, which may improve data collection processes.


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico por imagem , Redes Neurais de Computação , Aprendizado de Máquina , Algoritmos , Neuroimagem
7.
Neurourol Urodyn ; 41(7): 1612-1619, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35842826

RESUMO

OBJECTIVES: A number of neurourology imaging studies have mainly focused on investigating the brain activations during micturition in healthy and neuropathic patients. It is, however, also necessary to study brain functional connectivity (FC) within bladder-related regions to understand the brain organization during the execution of bladder function. This study aims to identify the altered brain network associated with bladder function in multiple sclerosis (MS) women with voiding dysfunction through comparisons with healthy subjects via concurrent urodynamic study (UDS)/functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: Ten healthy adult women and nine adult ambulatory women with clinically stable MS for ≥6 months and symptomatic voiding phase neurogenic lower urinary tract dysfunction (NLUTD) underwent UDS/fMRI evaluation with a task of bladder filling/emptying that was repeated three to five times. We quantitatively compared their FC within 17 bladder-related brain regions during two UDS phases: "strong desire to void" and "(attempt at) voiding initiation." RESULTS: At "strong desire to void," the healthy group showed significantly stronger FC in regions involved in bladder filling and suppression of voiding compared to the patient group. These regions included the bilateral anterior cingulate cortex, right supplementary motor area, and right middle frontal gyrus. During "(attempt at) voiding initiation," healthy subjects exhibited stronger FC in the right inferior frontal gyrus compared to MS patients. CONCLUSION: Our study offers a new way to identify alterations in the neural mechanisms underlying NLUTD and provides potential targets for clinical interventions (such as cortical neuromodulation) aimed at restoring bladder functions in MS patients.


Assuntos
Esclerose Múltipla , Bexiga Urinária , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Micção , Urodinâmica
8.
J Appl Clin Med Phys ; 23(11): e13765, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36052983

RESUMO

Class solution template trajectories are used clinically for efficiency, safety, and reproducibility. The aim was to develop class solutions for single cranial metastases radiotherapy/radiosurgery based on intracranial target positioning and compare to patient-specific trajectories in the context of 4π optimization. Template trajectories were constructed based on the open-source Montreal Neurological Institute (MNI) average brain. The MNI brain was populated with evenly spaced spherical target volumes (2 cm diameter, N = 243) and organs-at-risk (OARs) were identified. Template trajectories were generated for six anatomical regions (frontal, medial, and posterior, each with laterality dependence) based on previously published 4π optimization methods. Volumetric modulated arc therapy (VMAT) treatment plans generated using anatomically informed template 4π trajectories and patientspecific 4π trajectories were compared against VMAT plans from a standard four-arc template. Four-arc optimization techniques were compared to the standard VMAT template by placing three spherical targets in each of six anatomical regions of a test patient. This yielded 54 plans to compare various plan quality metrics. Increasing plan technique complexity, the total number of OAR maximum dose reductions compared to the standard arc template for the 6 anatomical classes was 4+/-2 (OFIXEDc) and 7+/-2 (OFIXEDi). In 65.6% of all cases, optimized fixed-couch positions outperformed the standard-arc template. Of the three comparisons, the most complex (OFIXEDi) showed the greatest statistical significance compared to the least complex (VMATi) across 12 plan quality metrics of maximum dose to each OAR, V12Gy, total plan Monitor Units, conformity index, and gradient index (p < 0.00417). In approximately 70% of all cases, 4π optimization methods outperformed the standard-arc template in terms of maximum dose reduction to OAR, by exclusively changing the arc geometry. We conclude that a tradeoff exists between complexity of a class solution methodology compared to patient-specific methods for arc selection, in the context of plan quality improvement.


Assuntos
Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Radioterapia de Intensidade Modulada/métodos
9.
Behav Brain Sci ; 45: e190, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36172785

RESUMO

Bruineberg and colleagues highlight work using Markov blankets to demarcate the bounds of the mind. This echoes earlier attempts to demarcate the bounds of the mind from a dynamical systems perspective. Advocates of mechanistic explanation have challenged the dynamical approach to independently motivate the application of the formalism, a challenge that Markov blanket theorists must also meet.

10.
Arch Phys Med Rehabil ; 101(4): 599-606, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31821798

RESUMO

OBJECTIVE: To investigate the feasibility of conducting exoskeleton-assisted gait training (EGT) and the effects of EGT on gait, metabolic expenditure, and physical function in persons with multiple sclerosis (MS). DESIGN: Single-group pilot study. SETTING: Research laboratory in a rehabilitation hospital. PARTICIPANTS: Individuals with MS (N=10; mean age, 54.3±12.4y) and Expanded Disability Status Scale 6.0-7.5. INTERVENTIONS: All participants completed up to 15 sessions of EGT. MAIN OUTCOME MEASURES: Timed 25-foot walk test at self-selected and fast speed, 6-minute walk test, metabolic expenditure of walking and timed Up and Go test were assessed during walking without the exoskeleton at baseline and immediate post training. RESULTS: All participants tolerated the training intensity and completed training without adverse events. After training, gait speed was improved and metabolic expenditure was reduced significantly during the timed 25-foot walk test at self-selected speed. CONCLUSIONS: EGT is not only feasible but may also improve gait efficiency for persons with MS. Our observed improvement in gait speed was associated with reduced metabolic expenditure, which was likely because of improved neuromotor coordination. Further studies are required to investigate the effectiveness and integration of EGT in the continuum of MS rehabilitation.


Assuntos
Exoesqueleto Energizado , Transtornos Neurológicos da Marcha/reabilitação , Esclerose Múltipla/reabilitação , Adulto , Idoso , Teste de Esforço , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Projetos Piloto , Velocidade de Caminhada
11.
J Neuroophthalmol ; 40(4): 558-565, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32991388

RESUMO

BACKGROUND: Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, idebenone has been shown to be safe and to provide a trend toward improved visual acuity, but long-term evidence of effectiveness in real-world clinical practice is sparse. METHODS: Open-label, multicenter, retrospective, noncontrolled analysis of long-term visual acuity and safety in 111 LHON patients treated with idebenone (900 mg/day) in an expanded access program. Eligible patients had a confirmed mitochondrial DNA mutation and had experienced the onset of symptoms (most recent eye) within 1 year before enrollment. Data on visual acuity and adverse events were collected as per normal clinical practice. Efficacy was assessed as the proportion of patients with either a clinically relevant recovery (CRR) or a clinically relevant stabilization (CRS) of visual acuity. In the case of CRR, time to and magnitude of recovery over the course of time were also assessed. RESULTS: At time of analysis, 87 patients had provided longitudinal efficacy data. Average treatment duration was 25.6 months. CRR was observed in 46.0% of patients. Analysis of treatment effect by duration showed that the proportion of patients with recovery and the magnitude of recovery increased with treatment duration. Average gain in best-corrected visual acuity for responders was 0.72 logarithm of the minimal angle of resolution (logMAR), equivalent to more than 7 lines on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Furthermore, 50% of patients who had a visual acuity below 1.0 logMAR in at least one eye at initiation of treatment successfully maintained their vision below this threshold by last observation. Idebenone was well tolerated, with most adverse events classified as minor. CONCLUSIONS: These data demonstrate the benefit of idebenone treatment in recovering lost vision and maintaining good residual vision in a real-world setting. Together, these findings indicate that idebenone treatment should be initiated early and be maintained more than 24 months to maximize efficacy. Safety results were consistent with the known safety profile of idebenone.


Assuntos
Atrofia Óptica Hereditária de Leber/tratamento farmacológico , Ubiquinona/análogos & derivados , Acuidade Visual , Adolescente , Adulto , Idoso , Antioxidantes/uso terapêutico , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Óptica Hereditária de Leber/fisiopatologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Ubiquinona/uso terapêutico , Adulto Jovem
12.
J Neurosci Res ; 96(7): 1176-1185, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29607550

RESUMO

Although the thalamus is not considered primarily as a limbic structure, abundant evidence indicates the essential role of the thalamus as a modulator of limbic functions indirectly through the amygdala. The amygdala is a central component of the limbic system and serves an essential role in modulating the core processes including the memory, decision-making, and emotional reactions. The amygdalothalamic pathway is the largest direct amygdalo-diencephalic connection in the primates including the human brain. Given the crucial role of the amygdalothalamic tract (ATT) in memory function and diencephalic amnesia in stroke patients, diffusion tensor imaging may be helpful in better visualizing the surgical anatomy of this pathway noninvasively. To date, few diffusion-weighted studies have focused on the amygdala, yet the fine neuronal connection of the amygdala and thalamus known as the ATT has yet to be elucidated. This study aimed to investigate the utility of high spatial resolution diffusion tensor tractography for mapping the trajectory of the ATT in the human brain. We studied 15 healthy right-handed human subjects (12 men and 3 women with age range of 24-37 years old). Using a high-resolution diffusion tensor tractography technique, for the first time, we were able to reconstruct and measure the trajectory of the ATT. We further revealed the close relationship of the ATT with the temporopontine tract and the fornix bilaterally in 15 healthy adult human brains.


Assuntos
Tonsila do Cerebelo/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Sistema Límbico/anatomia & histologia , Tálamo/anatomia & histologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento Tridimensional , Sistema Límbico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/anatomia & histologia , Tálamo/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem
13.
J Magn Reson Imaging ; 46(2): 557-564, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27869333

RESUMO

PURPOSE: To improve the conspicuity of white matter lesions (WMLs) in multiple sclerosis (MS) using patient-specific optimization of single-slab 3D fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI). MATERIALS AND METHODS: Sixteen MS patients were enrolled in a prospective 3.0T MRI study. FLAIR inversion time and echo time were automatically optimized for each patient during the same scan session based on measurements of the relative proton density and relaxation times of the brain tissues. The optimization criterion was to maximize the contrast between gray matter (GM) and white matter (WM), while suppressing cerebrospinal fluid. This criterion also helps increase the contrast between WMLs and WM. The performance of the patient-specific 3D FLAIR protocol relative to the fixed-parameter protocol was assessed both qualitatively and quantitatively. RESULTS: Patient-specific optimization achieved a statistically significant 41% increase in the GM-WM contrast ratio (P < 0.05) and 32% increase in the WML-WM contrast ratio (P < 0.01) compared with fixed-parameter FLAIR. The increase in WML-WM contrast ratio correlated strongly with echo time (P < 10-11 ). Two experienced neuroradiologists indicated substantially higher lesion conspicuity on the patient-specific FLAIR images over conventional FLAIR in 3-4 cases (intrarater correlation coefficient ICC = 0.72). In no case was the image quality of patient-specific FLAIR considered inferior to conventional FLAIR by any of the raters (ICC = 0.32). CONCLUSION: Changes in proton density and relaxation times render fixed-parameter FLAIR suboptimal in terms of lesion contrast. Patient-specific optimization of 3D FLAIR increases lesion conspicuity without scan time penalty, and has potential to enhance the detection of subtle and small lesions in MS. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:557-564.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Líquido Cefalorraquidiano , Meios de Contraste/química , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
14.
Urol Clin North Am ; 51(2): 177-185, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609190

RESUMO

Lower urinary tract symptoms (LUTS) are highly prevalent in individuals with multiple sclerosis (MS). However, assessment of these symptoms is often hindered by vague definitions or absence of screening in asymptomatic patients. It is crucial to exercise caution when applying the non-neurogenic definition of urinary retention in this population. For men with MS experiencing persistent and treatment-resistant LUTS, urodynamic studies should be used to identify the underlying causes of symptoms. Although numerous therapies are presently accessible for managing LUTS in MS, there is a need for further investigation into emerging treatments such as percutaneous tibial nerve, and noninvasive brain stimulation.


Assuntos
Sintomas do Trato Urinário Inferior , Esclerose Múltipla , Masculino , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/terapia , Sintomas do Trato Urinário Inferior/diagnóstico , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/terapia
15.
Sci Rep ; 14(1): 17157, 2024 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060426

RESUMO

In addition to focal lesions, diffusely abnormal white matter (DAWM) is seen on brain MRI of multiple sclerosis (MS) patients and may represent early or distinct disease processes. The role of MRI-observed DAWM is understudied due to a lack of automated assessment methods. Supervised deep learning (DL) methods are highly capable in this domain, but require large sets of labeled data. To overcome this challenge, a DL-based network (DAWM-Net) was trained using semi-supervised learning on a limited set of labeled data for segmentation of DAWM, focal lesions, and normal-appearing brain tissues on multiparametric MRI. DAWM-Net segmentation performance was compared to a previous intensity thresholding-based method on an independent test set from expert consensus (N = 25). Segmentation overlap by Dice Similarity Coefficient (DSC) and Spearman correlation of DAWM volumes were assessed. DAWM-Net showed DSC > 0.93 for normal-appearing brain tissues and DSC > 0.81 for focal lesions. For DAWM-Net, the DAWM DSC was 0.49 ± 0.12 with a moderate volume correlation (ρ = 0.52, p < 0.01). The previous method showed lower DAWM DSC of 0.26 ± 0.08 and lacked a significant volume correlation (ρ = 0.23, p = 0.27). These results demonstrate the feasibility of DL-based DAWM auto-segmentation with semi-supervised learning. This tool may facilitate future investigation of the role of DAWM in MS.


Assuntos
Encéfalo , Aprendizado Profundo , Imageamento por Ressonância Magnética Multiparamétrica , Esclerose Múltipla , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Masculino , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Feminino , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Adulto , Pessoa de Meia-Idade , Aprendizado de Máquina Supervisionado , Imageamento por Ressonância Magnética/métodos
17.
Phys Med Biol ; 68(15)2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37369237

RESUMO

Objective. Non-coplanar arc geometry optimizations that take advantage of beam's eye view (BEV) geometric overlap information have been proven to reduce dose to healthy organs-at-risk (OARs). Recently, a metric called mean arc distance (MAD) has been developed that quantifies the arc geometry sampling of 4πspace. The purpose of this research is to combine improved BEV overlap information with MAD to generate static couch lung stereotactic body radiotherapy (SBRT) treatment plans deliverable on a C-arm linear accelerator.Approach. An algorithm utilizing the Moller-Trumbore ray-triangle intersection method was employed to compute a cost surrogate for dose to overlapping OARs using distances interpolated onto a PDD. Cost was combined with MAD for 100 000 random combinations of arc trajectories. A pathfinding algorithm for arc selection was created, balancing the contributions of MAD and 4πcost for the final trajectory. This methodology was evaluated for 18 lung SBRT patients. Cases were also planned with arcs from a clinical treatment template protocol for dosimetric and plan quality comparison. Results were evaluated using dose constraints in the context of RTOG0915.Main results. Five of six OARs had maximum dose reductions when planned with the arc trajectory optimization algorithm. Significant maximum dose reductions were found for esophagus (7.41 ± 0.91 Gy,p= 0.00019), trachea (5.56 ± 1.55 Gy,p= 0.0025), spinal cord (2.87 ± 1.13 Gy,p= 0.039), large bronchus (3.47 ± 1.49 Gy,p= 0.0075), and aorta (3.13 ± 0.99 Gy,p= 0.012). Mean dose to contralateral lung was also significantly reduced (0.50 ± 0.06 Gy,p= 0.00019). There were two significant increases in OAR doses: mean dose to ipsilateral lung (0.40 ± 0.09,p= 0.00086) and V5Gyto ipsilateral lung (1.95 ± 0.70%,p= 0.011). Paddick conformity index increased by 0.03 ± 0.02 (p= 0.14), remaining below a limit of 1.2 for both techniques.Significance. Static couch non-coplanar optimization yielded maximum dose reductions to OARs while maintaining target conformity for lung SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Radiocirurgia/métodos , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Pulmão , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Órgãos em Risco
18.
Brain Res ; 1817: 148510, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37488033

RESUMO

The hypothalamus plays essential roles in the human brain by regulating feeding, fear, aggression, reproductive behaviors, and autonomic activities. The septal nuclei and the bed nucleus of stria terminalis (BNST) are also known to be involved in control of autonomic, motivational, learning, emotional and associative processes in the human brain. Multiple animal dissection studies have revealed direct connectivity between central limbic gray matter nuclei and occipital cortex, particularly from the hypothalamic, septal and BNST nuclei. However, the detailed anatomy of this connectivity in the human brain has yet to be determined. The primary objective of this study was to explore the utility of high spatial and high angular resolution diffusion weighted tractography techniques for mapping the connectivity pathways between the occipital cortex and central limbic gray matter nuclei in the human brain. We studied 30 healthy adult human brains, delineated, and reconstructed the trajectory of the occipito-hypothalamic/septal/BNST for the first time in the human brain.


Assuntos
Núcleos Septais , Adulto , Animais , Humanos , Núcleos Septais/diagnóstico por imagem , Núcleos Septais/fisiologia , Encéfalo , Imagem de Tensor de Difusão , Hipotálamo , Lobo Occipital
19.
Brain Behav ; 13(7): e3042, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37218403

RESUMO

BACKGROUND AND PURPOSE: The discovery of glymphatic function in the human brain has generated interest in waste clearance mechanisms in neurological disorders such as multiple sclerosis (MS). However, noninvasive in vivo functional assessment is currently lacking. This work studies the feasibility of a novel intravenous dynamic contrast MRI method to assess the dural lymphatics, a purported pathway contributing to glymphatic clearance. METHODS: This prospective study included 20 patients with MS (17 women; age = 46.4 [27, 65] years; disease duration = 13.6 [2.1, 38.0] years, expanded disability status score (EDSS) = 2.0 [0, 6.5]). Patients were scanned on a 3.0T MRI system using intravenous contrast-enhanced fluid-attenuated inversion recovery MRI. Signal in the dural lymphatic vessel along the superior sagittal sinus was measured to calculate peak enhancement, time to maximum enhancement, wash-in and washout slopes, and the area under the time-intensity curve (AUC). Correlation analysis was performed to examine the relationship between the lymphatic dynamic parameters and the demographic and clinical characteristics, including the lesion load and the brain parenchymal fraction (BPF). RESULTS: Contrast enhancement was detected in the dural lymphatics in most patients 2-3 min after contrast administration. BPF had a significant correlation with AUC (p < .03), peak enhancement (p < .01), and wash-in slope (p = .01). Lymphatic dynamic parameters did not correlate with age, BMI, disease duration, EDSS, or lesion load. Moderate trends were observed for correlation between patient age and AUC (p = .062), BMI and peak enhancement (p = .059), and BMI and AUC (p = .093). CONCLUSION: Intravenous dynamic contrast MRI of the dural lymphatics is feasible and may be useful in characterizing its hydrodynamics in neurological diseases.


Assuntos
Vasos Linfáticos , Esclerose Múltipla , Humanos , Feminino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Estudos Prospectivos , Vasos Linfáticos/diagnóstico por imagem , Vasos Linfáticos/metabolismo , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
20.
Mult Scler Relat Disord ; 74: 104727, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37086639

RESUMO

BACKGROUND: Trigeminal neuralgia (TN) is a well-recognized symptom of multiple sclerosis (MS), yet its clinical characteristics related to MS subtype is poorly studied. Our aim was to evaluate whether development and clinical outcome of TN are influenced by MS phenotype. METHODS: In this retrospective cohort study, our database from 2007 to 2022 was reviewed to identify patients who had both the diagnosis of MS and TN, whether TN was an initial symptom of MS or developed later in diagnosis. A detailed medical history and treatment outcome was obtained. Pain status was assessed retrospectively using the Barrow Neurological Institute Pain Scale (BNI-PS), with BNI-PS I-III considered as good pain control and BNI-PS IV-V as poor pain control. RESULTS: 58 patients had MS-related TN. 44 patients had relapsing remitting multiple sclerosis (RRMS) at the time of TN diagnosis, 11 had secondary progressive multiple sclerosis (SPMS) at the time of TN diagnosis, and type of MS was not clear in 3 patients at the time of TN diagnosis (either RRMS or SPMS). Over a mean follow up of 18.8 (SD=10.9) years, 30 transitioned to SPMS. TN was refractory to medical management in 9 RRMS and 22 SPMS patients (p = 0.001). TN patients with RRMS required lower median number of pain medications compared to SPMS (p = 0.014). Brain MRI was available in 41 of the entire cohort. Of these, 27 patients had demyelinating lesions in the trigeminal sensory pathway and 14 did not. Patients with existing lesions had a higher chance of failure of medical management (74% versus 36%, p = 0.017) and required surgical intervention (55% versus 7%, p = 0.003). DISCUSSION: TN was not seen in primary progressive multiple sclerosis (PPMS). In patients who transitioned to SPMS, TN was more likely to be refractory to medical management. TN was more refractory in the presence of demyelinating plaque involving trigeminal sensory pathway.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Radiocirurgia , Neuralgia do Trigêmeo , Humanos , Neuralgia do Trigêmeo/complicações , Neuralgia do Trigêmeo/diagnóstico por imagem , Estudos Retrospectivos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Resultado do Tratamento , Dor/complicações , Esclerose Múltipla Recidivante-Remitente/complicações
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