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BACKGROUND: The dentatorubrothalamic tract (DRTT) remains understudied in idiopathic cervical dystonia (CD), despite evidence that the pathway is relevant in the pathophysiology of the disorder. OBJECTIVE: The aim of this study was to examine the DRTT in patients with CD using diffusion tensor imaging (DTI)-based tractography. METHODS: Magnetic resonance imaging scans from 67 participants were collected to calculate diffusion tractography metrics using a binary tractography-based DRTT template. Fractional anisotropy and diffusivity measures of left and right DRTT were computed and compared between 32 subjects with CD and 35 age-matched healthy volunteers. RESULTS: Fractional anisotropy of right DRTT and mean and axial diffusivity of left DRTT were significantly reduced in patients with CD. Similar abnormalities were observed in patients with focal CD and patients with CD without tremor. DTI metrics did not correlate with disease duration or severity. CONCLUSIONS: Significant reductions in DTI measures suggest microstructural abnormalities within the DRTT in CD, characterized by a tractography pattern consistent with decreased axonal integrity. © 2021 International Parkinson and Movement Disorder Society.
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Imagem de Tensor de Difusão , Torcicolo , Anisotropia , Imagem de Difusão por Ressonância Magnética , Humanos , Torcicolo/diagnóstico por imagemRESUMO
AIM: Structural, functional, and metabolic changes in the dorsolateral prefrontal cortex (DLPFC) are implicated in the pathogenesis of major depressive disorder (MDD). We used proton magnetic resonance spectroscopy ((1) H-MRS) to examine the metabolite choline (glycerophosphocholine plus phosphocholine), which is used as an index of membrane integrity in the left DLPFC, in adolescents and young adults with MDD who were treatment-resistant and had a positive family history compared to healthy controls. Differences in the choline resonance indicate an imbalance between synthesis and degradation activity of neuronal and glia membrane phospholipids. METHODS: Seventeen adolescents with MDD and 11 healthy controls underwent (1) H-MRS. A short echo point-resolved spectroscopy (echo time = 30 ms, repetition time = 2000 ms) protocol was used with a voxel (4.5cm(3) , 128 averages) placed within the left DLPFC. RESULTS: There were significantly increased choline (P = 0.04) and creatine concentrations (P = 0.005) in the left DLPFC of the MDD group compared to controls. In MDD participants, choline concentration correlated with scores on the Beck Depression Inventory (r = 0.41, P = 0.03). CONCLUSION: Increased left DLPFC choline and creatine levels in depressed adolescents may be biomarkers for the disorder. The increased choline levels may indicate abnormalities in neuronal membrane integrity, and the increased creatine could be reflective of altered energy demands and metabolism.
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Colina/metabolismo , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Resistente a Tratamento/metabolismo , Córtex Pré-Frontal/metabolismo , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: Choosing Wisely Canada and most major anesthesia and preoperative guidelines recommend against obtaining preoperative tests before low-risk procedures. However, these recommendations alone have not reduced low-value test ordering. In this study, the theoretical domains framework (TDF) was used to understand the drivers of preoperative electrocardiogram (ECG) and chest X-ray (CXR) ordering for patients undergoing low-risk surgery ('low-value preoperative testing') among anesthesiologists, internal medicine specialists, nurses, and surgeons. METHODS: Using snowball sampling, preoperative clinicians working in a single health system in Canada were recruited for semi-structured interviews about low-value preoperative testing. The interview guide was developed using the TDF to identify the factors that influence preoperative ECG and CXR ordering. Interview content was deductively coded using TDF domains and specific beliefs were identified by grouping similar utterances. Domain relevance was established based on belief statement frequency, presence of conflicting beliefs, and perceived influence over preoperative test ordering practices. RESULTS: Sixteen clinicians (7 anesthesiologists, 4 internists, 1 nurse, and 4 surgeons) participated. Eight of the 12 TDF domains were identified as the drivers of preoperative test ordering. While most participants agreed that the guidelines were helpful, they also expressed distrust in the evidence behind them (knowledge). Both a lack of clarity about the responsibilities of the specialties involved in the preoperative process and the ease by which any clinician could order, but not cancel tests, were drivers of low-value preoperative test ordering (social/professional role and identity, social influences, belief about capabilities). Additionally, low-value tests could also be ordered by nurses or the surgeon and may be completed before the anesthesia or internal medicine preoperative assessment appointment (environmental context and resources, beliefs about capabilities). Finally, while participants agreed that they did not intend to routinely order low-value tests and understood that these would not benefit patient outcomes, they also reported ordering tests to prevent surgery cancellations and problems during surgery (motivation and goals, beliefs about consequences, social influences). CONCLUSIONS: We identified key factors that anesthesiologists, internists, nurses, and surgeons believe influence preoperative test ordering for patients undergoing low-risk surgeries. These beliefs highlight the need to shift away from knowledge-based interventions and focus instead on understanding local drivers of behaviour and target change at the individual, team, and institutional levels.
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PURPOSE: Cerebellar connectivity is thought to be abnormal in cervical dystonia (CD) and other dystonia subtypes, based on evidence from imaging studies and animal work. The authors investigated whether transcranial magnetic stimulation-induced cerebellar brain inhibition (CBI), a measure of cerebellar efficiency at inhibiting motor outflow, is abnormal in patients with CD and/or is associated with clinical features of CD. Because of methodological heterogeneity in CBI reporting, the authors deployed additional controls to reduce potential sources of variability in this study. METHODS: Cerebellar brain inhibition was applied in 20 CD patients and 14 healthy control subjects. Cerebellar brain inhibition consisted of a cerebellar conditioning stimulus delivered at four different interstimulus intervals (ISIs) before a test stimulus delivered to hand muscle representation in the motor cortex. The average ratio of conditioned to unconditioned motor evoked potential was computed for each ISI. Cervical dystonia clinical severity was measured using the Toronto Western Spasmodic Torticollis Rating Scale. Control experiments involved neuronavigated transcranial magnetic stimulation, neck postural control in patients, and careful screening for noncerebellar pathway inhibition via cervicomedullary evoked potentials. RESULTS: There was no difference between CBI measured in healthy control subjects and CD patients at any of the four ISIs; however, CBI efficiency was significantly correlated with worsening CD clinical severity at the 5 ms ISI. CONCLUSIONS: Cerebellar brain inhibition is a variable measure in both healthy control subjects and CD patients; much of this variability may be attributed to experimental methodology. Yet, CD severity is significantly associated with reduced CBI at the 5 ms ISI, suggestive of cerebello-thalamo-cortical tract dysfunction in this disorder.
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Torcicolo , Humanos , Encéfalo , Cerebelo/fisiologia , Estimulação Magnética Transcraniana/métodos , Músculo Esquelético , Potencial Evocado Motor/fisiologia , Inibição Neural/fisiologiaRESUMO
BACKGROUND: Low back pain (LBP) is a leading cause of disability and is among the top five reasons that patients visit their family doctors. Over-imaging for non-specific low back pain remains a problem in primary care. To inform a larger study to develop and evaluate a theory-based intervention to reduce inappropriate imaging, we completed an assessment of the barriers and facilitators to reducing unnecessary imaging for NSLBP among family doctors in Newfoundland and Labrador (NL). METHODS: This was an exploratory, qualitative study describing family doctors' experiences and practices related to diagnostic imaging for non-specific LBP in NL, guided by the Theoretical Domains Framework (TDF). Data were collected using in-depth, semi-structured interviews. Transcripts were analyzed deductively (assigning text to one or more domains) and inductively (generating themes at each of the domains) before the results were examined to determine which domains should be targeted to reduce imaging. RESULTS: Nine family doctors (four males; five females) working in community (n = 4) and academic (n = 5) clinics in both rural (n = 6) and urban (n = 3) settings participated in this study. We found five barriers to reducing imaging for patients with NSLBP: 1) negative consequences, 2) patient demand 3) health system organization, 4) time, and 5) access to resources. These were related to the following domains: 1) beliefs about consequences, 2) beliefs about capabilities, 3) emotion, 4) reinforcement, 5) environmental context and resources, 6) social influences, and 7) behavioural regulation. CONCLUSIONS: Family physicians a) fear that if they do not image they may miss something serious, b) face significant patient demand for imaging, c) are working in a system that encourages unnecessary imaging, d) don't have enough time to counsel patients about why they don't need imaging, and e) lack access to appropriate practitioners, community programs, and treatment modalities to prescribe to their patients. These barriers were related to seven TDF domains. Successfully reducing inappropriate imaging requires a comprehensive intervention that addresses these barriers using established behaviour change techniques. These techniques should be matched directly to relevant TDF domains. The results of our study represent the important first step of this process - identifying the contextual barriers and the domains to which they are related.
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Dor Lombar , Terapia Comportamental , Diagnóstico por Imagem , Feminino , Humanos , Dor Lombar/diagnóstico , Masculino , Terra Nova e Labrador , Atenção Primária à SaúdeRESUMO
Background: Major depressive disorder (MDD) is common in youth and treatment options are limited. We evaluated the effectiveness and safety of repetitive transcranial magnetic stimulation (rTMS) in adolescents and transitional aged youth with treatment resistant MDD. Methods: Thirty-two outpatients with moderate to severe, treatment-resistant MDD, aged 13-21 years underwent a three-week, open-label, single center trial of rTMS (ClinicalTrials.gov identifier NCT01731678). rTMS was applied to the left dorsolateral prefrontal cortex (DLPFC) using neuronavigation and administered for 15 consecutive week days (120% rest motor threshold; 40 pulses over 4 s [10 Hz]; inter-train interval, 26 s; 75 trains; 3,000 pulses). The primary outcome measure was change in the Hamilton Depression Rating Scale (Ham-D). Treatment response was defined as a >50% reduction in Ham-D scores. Safety and tolerability were also examined. Results: rTMS was effective in reducing MDD symptom severity (t = 8.94, df = 31, p < 0.00001). We observed 18 (56%) responders (≥ 50% reduction in Ham-D score) and 14 non-responders to rTMS. Fourteen subjects (44%) achieved remission (Ham-D score ≤ 7 post-rTMS). There were no serious adverse events (i.e., seizures). Mild to moderate, self-limiting headaches (19%) and mild neck pain (16%) were reported. Participants ranked rTMS as highly tolerable. The retention rate was 91% and compliance rate (completing all study events) was 99%. Conclusions: Our single center, open trial suggests that rTMS is a safe and effective treatment for youth with treatment resistant MDD. Larger randomized controlled trials are needed. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT01731678.
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PLAIN ENGLISH SUMMARY: The Alberta Depression Research Priority Setting Project aimed to meaningfully involve patients, families and clinicians in determining a research agenda aligned to the needs of Albertans who have experienced depression. The project was modeled after a process developed in the UK by the James Lind Alliance and adapted to fit the Alberta, Canada context. This study describes the processes used to ensure the voices of people with lived experience of depression were integrated throughout the project stages. The year long project culminated with a facilitated session to identify the top essential areas of depression research focus. People with lived experience were engaged as part of the project's Steering Committee, as survey participants and as workshop participants. It is hoped this process will guide future priority setting opportunities and advance depression research in Alberta. ABSTRACT: Background The Depression Research Priority Setting (DRPS) project has the clear aim of describing the patient engagement process used to identify depression research priorities and to reflect on the successes of this engagement approach, positive impacts and opportunities for improvement. To help support patient-oriented depression research priority setting in Alberta, the Patient Engagement (PE) Platform of the Alberta Strategy for Patient Oriented Research Support for People and Patient-Oriented Research and Trials (SUPPORT) Unit designed, along with the support of their partners in addictions and mental health, an explit process to engage patients in the design and execution of the DRPS. Methods The UK's James Lind Alliance (JLA) Priority Setting Partnership (PSP) method was adapted into a six step process to ensure voices of "people with lived experience" (PWLE) with depression were included throughout the project stages. This study uses an explicit and parallel patient engagement process throughout each estage of the PSP designed by the PE Platform. Patient engagement was divided into a five step process: i) Awareness and relationship building; ii) Co-designing and co-developing a shared decision making process; iii) Collaborative communication; iv) Collective sensemaking; and v) Acknowledgement, celebration and recognition. A formative evaluation of the six PE processes was undertaken to explore the success of the parallel patient engagement process. Results This project was successful in engaging people with lived depression experience as partners in research priority setting, incorporating their voices into the discussions and decisions that led to the top 25 depression research questions. Conclusions The DRPS project has positively contributed to depression research in Canada by identifying the priorities of Albertans who have experienced depression for depression research. Dissemination activities to promote further knowledge exchange of prioritized research questions, with emphasis on the importance of process in engaging the voices of PWLE of depression are planned.
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BACKGROUND: To support patient-oriented setting of priorities for depression research in Alberta, the Patient Engagement Platform of the Alberta Strategy for Patient Oriented Research's Support for People and Patient-Oriented Research and Trials Unit and Alberta Health Services' Addiction and Mental Health Strategic Clinical Network, along with partners in addictions and mental health, designed the Alberta Depression Research Priority Setting Project. The aim of the project was to survey patients, caregivers and clinicians/researchers in Alberta about what they considered to be the most important unanswered questions about depression. METHODS: The project adapted the James Lind Alliance Priority Setting Partnership method into a 6-step process to gather and prioritize questions about depression posed by people with lived depression experience, which included patients, caregivers, clinicians and health care practitioners. RESULTS: Implementation of the project, from initial data collection to final priority setting, took 10 months (August 2016 to June 2017). A total of 445 Albertans with lived experience of depression participated, ultimately identifying 11 priority depression research questions spanning the health continuum, life stages, and treatment and prevention opportunities. INTERPRETATION: This project is a fundamental step that has the potential to positively influence depression research. Including the voices of Albertans with lived experience will create advantages for depression research for Albertans, researchers and research funders, and for patient engagement in the research enterprise overall.
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BACKGROUND: Smaller hippocampal volumes, as assessed by magnetic resonance imaging (MRI), and proton magnetic resonance spectroscopy (1H-MRS) indexed alterations in brain metabolites have been identified in adults with major depressive disorder (MDD). Our group has found similar effects in MDD youth. However, this has not been studied in youth with treatment resistant MDD (TRD), nor has the interaction between regional N-acetyl-aspartate and volume deficits. N-acetyl-aspartate is an amino acid in the synthesis pathway of glutamate, and serves a marker of neuronal viability/number. METHODS: Fifteen typically developing youth (16-22 years of age; 7 males, 8 females) and eighteen youth with TRD (14-22 years of age; 8 males, 10 females) underwent 1H-MRS and MRI on a 3T scanner. A short echo PRESS protocol was used with voxels in the right and left hippocampi (6mL each). Hippocampal volume was evaluated using FreeSurfer. RESULTS: Compared with the typically developing group, youth with TRD had lower concentrations of N-acetyl-aspartate in the left hippocampus (p=0.004), and a trend for smaller left hippocampal volume (p=0.067). In TRD subjects, hippocampal N-acetyl-aspartate was inversely correlated with left (r=-0.68, p=0.003) but not right hippocampal volume. Right hippocampal glutamate+glutamine was greater in TRD youth compared to typically developing controls (p=0.007). CONCLUSIONS: These results suggest a neurochemical and structural deficit in the hippocampi of youth with TRD. These findings fit with the role of N-acetyl-aspartate in glutamate neurotransmission and the effect of glutamate on brain morphology.