Brain Structural Changes in Focal Dystonia-What About Task Specificity? A Multimodal MRI Study.

BACKGROUND: The neural basis of task specificity in dystonia is still poorly understood. This study investigated gray and white matter (WM) brain alterations in patients with task-specific dystonia (TSD) and non-task-specific dystonia (NTSD). METHODS: Thirty-six patients with TSD (spasmodic dysphonia, writer's cramp), 61 patients with NTSD (blepharospasm, cervical dystonia), and 83 healthy controls underwent 3D T1-weighted and diffusion tensor magnetic resonance imaging (MRI). Whole brain cortical thickness and voxel-based morphometry; volumes of basal ganglia, thalamus, nucleus accumbens, amygdala, and hippocampus; and WM damage were assessed. Analysis of variance models were used to compare MRI measures between groups, adjusting for age and botulinum toxin (BoNT) treatment. RESULTS: The comparison between focal dystonia patients showed cortical thickness and gray matter (GM) volume differences (ie, decreased in NTSD, increased in TSD) in frontal, parietal, temporal, and occipital cortical regions; basal ganglia; thalamus; hippocampus; and amygdala. Cerebellar atrophy was found in NTSD patients relative to controls. WM damage was more severe and widespread in task-specific relative to NTSD patients. TSD patients receiving BoNT, relative to nontreated patients, had cortical thickening and increased GM volume in frontoparietal, temporal, and occipital regions. NTSD patients experiencing pain showed cortical thickening of areas involved in pain-inhibitory mechanisms. CONCLUSIONS: TSD and NTSD are characterized by opposite alterations of the main cortical and subcortical sensorimotor and cognitive-controlling brain structures, suggesting the possible presence of different pathophysiological and/or compensatory mechanisms underlying the complexity of the two clinical phenotypes of focal dystonia. © 2020 International Parkinson and Movement Disorder Society.

Optical coherence tomography in patients with Wilson's disease.

OBJECTIVES: Wilson disease (WD) is an autosomal recessive disorder that leads to copper accumulation and deposition in different organs, frequently affecting visual pathways. Recent studies have detected morphological changes of the retina in patients with WD using optical coherence tomography (OCT). Measuring the thickness of the retinal nerve fibre layer (RNFL) with OCT provides an objective assessment of integrity and morphological abnormalities of the retina. The aim of this study was to evaluate the relationship between OCT parameters and form of the disease, therapy and symptoms duration, as well as severity of neurological impairment. METHODS: The study comprised of 52 patients with WD and 52 healthy controls (HC). All the patients were on a regular and stable chelation therapy and/or zinc salts. Patients were divided into two groups, with neurological (NWD) or hepatic form of the disease (HWD). OCT was performed to assess the RNFL thickness. RESULTS: The WD patients had significantly lower intraocular pressure in both eyes and lower RNFL thickness than the HC. There were no differences between NWD and HWD in any of the ophthalmologically tested parameters. No significant correlations were found between clinical features and retinal thickness parameters. Stratification of the cohort according to the disease duration showed that disease duration did not influence the RNFL thickness. CONCLUSION: We found that involvement of the retina represented a subclinical finding in neurologically intact patients in the HWD group. Nevertheless, the value of OCT as a biomarker for the assessment of the clinical course and progression of WD still remains uncertain.

Psychiatric Symptoms in the Initial Motor Stage of Parkinson's Disease.

Neuropsychiatric symptoms (NPS) are common in Parkinson's disease (PD). The aim of this study was to estimate the correlates of NPS in patients with PD in the initial motor stage of the disease (hemiparkinsonism). A total of 111 patients with PD and 105 healthy control participants were assessed. Patients with PD experienced apathy, depression, and anxiety more frequently compared with healthy controls. Sleep disturbances occurred commonly in early PD patients. Patients with PD and mild cognitive impairment (MCI) had depression and anxiety more frequently, but not apathy, compared with patients with PD without MCI. The results of this study confirm a high burden of NPS even in the earliest motor stage of PD.

De novo mutation in the GNAL gene causing seemingly sporadic dystonia in a Serbian patient.

BACKGROUND: Mutations in GNAL (DYT25) have recently been established as the first confirmed cause of focal or segmental adult-onset dystonia. Mutation carriers show craniocervical involvement; however, the GNAL mutational and phenotypic spectrum remain to be further characterized, and guidelines for diagnostic testing need to be established. METHODS: The authors used Sanger sequencing to test for changes in the GNAL coding or splice-site regions in 236 Serbian patients suffering from isolated dystonia with craniocervical involvement. RESULTS: One novel likely pathogenic substitution (c.1061T>C; p.Val354Ala) in GNAL was detected in a sporadic cervical dystonia patient (mutation frequency: 0.4%). This mutation was not present in the DNA of either parent, despite confirmed parentage. CONCLUSIONS: This is the first report of a de novo GNAL mutation causing genetically proven, seemingly sporadic DYT25 dystonia. Our finding highlights the importance of genetic testing for GNAL mutations in establishing the molecular diagnosis even for patients with a negative family history.

White matter abnormalities in Parkinson's disease patients with glucocerebrosidase gene mutations.

Glucocerebrosidase gene mutations represent a genetic risk factor for the development of Parkinson's disease. This study investigated brain alterations in Parkinson's disease patients carrying heterozygous glucocerebrosidase gene mutations using structural and diffusion tensor magnetic resonance imaging. Among 360 Parkinson's disease patients screened for glucocerebrosidase gene mutations, 19 heterozygous mutation carriers (5.3%) were identified. Of these, 15 patients underwent a neuropsychological evaluation and a magnetic resonance imaging scan. Sixteen age- and sex-matched healthy controls and 14 idiopathic Parkinson's disease patients without glucocerebrosidase gene mutations were also studied. Tract-based spatial statistics was used to perform a white matter voxel-wise analysis of diffusion tensor magnetic resonance imaging metrics. Mean fractional anisotropy values were obtained from white matter tracts of interest. Voxel-based morphometry was used to assess gray-matter atrophy. Cognitive deficits were found in 9 mutation carrier patients (60%). Compared with controls, Parkinson's disease patients carrying glucocerebrosidase gene mutations showed decreased fractional anisotropy in the olfactory tracts, corpus callosum, and anterior limb of the internal capsule bilaterally, as well as in the right anterior external capsule, and left cingulum, parahippocampal tract, parietal portion of the superior longitudinal fasciculus, and occipital white matter. Mutation carrier patients also had decreased fractional anisotropy of the majority of white matter tracts compared with Parkinson's disease patients with no mutations. No white matter abnormalities were found in Parkinson's disease patients without glucocerebrosidase gene mutations. No gray matter difference was found between patients and controls. In Parkinson's disease patients, verbal fluency scores correlated with white matter abnormalities. Parkinson's disease patients carrying glucocerebrosidase gene mutations experience a distributed pattern of white matter abnormalities involving the interhemispheric, frontal corticocortical, and parahippocampal tracts. White matter pathology in these patients may have an impact on the clinical manifestations of the disease, including cognitive impairment.

Cerebral Amyloid Angiopathy-Related Inflammation (CAA-rI): Three Heterogeneous Case Reports and a Focused Literature Review.

Cerebral amyloid angiopathy-related inflammation (CAA-rI) is a largely reversible, subacute encephalopathy, which is considered as a rare variant of cerebral amyloid angiopathy (CAA). Although the diagnosis of this inflammatory vasculopathy is generally clinico-pathologic, a probable or possible diagnosis can often be established based on current clinico-radiological diagnostic criteria. This is important since CAA-rI is considered as a treatable disorder, which most commonly occurs in the elderly population. Behavioral changes and cognitive deterioration are highlighted as the most common clinical signs of CAA-rI, followed by a heterogeneous spectrum of typical and atypical clinical presentations. However, despite the well-established clinical and radiological features incorporated in the current diagnostic criteria for this CAA variant, this rare disorder is still insufficiently recognized and treated. Here, we have shown three patients diagnosed with probable CAA-rI, with significant heterogeneity in the clinical and neuroradiological presentations, followed by different disease courses and outcomes after the introduction of immunosuppressive treatment. Moreover, we have also summarized up-to-date literature data about this rare, yet underdiagnosed, immune-mediated vasculopathy.

Long-term outcome of patients with neurological form of Wilson's disease compliant to the de-coppering treatment.

BACKGROUND: A substantial proportion of Wilson's disease (WD) patients exhibit residual neurological symptoms. Data on the prognostic value of initial clinical features and treatment choices in WD patients compliant to the therapy is relatively sparse. AIM: The aim of the present study was to identify predictors of the long-term outcome of patients with WD with good treatment adherence. METHODS: Forty patients with neurological form of WD were evaluated before the de-coppering treatment initiation (based on the medical records) and after mean 15.25 ± 11.24 years of the stable treatment. Severity of neurological symptoms were assessed with a tier two of Global Assessment Scale (GAS) for Wilson's Disease. RESULTS: The most frequent symptoms prior to treatment initiation were dysarthria (90%), tremor (90%), clumsiness (67.5%), depression (67.5%), and gait disturbance (62.5%). Significant decrease in the frequency of dysarthria, clumsiness, tremor, gait disturbance, postural instability and an improvement in school/work performance were observed after the long-term treatment, while frequency of dysphagia, drooling, bradykinesia and rigidity, dystonic and choreatic features did not change. Overall symptom severity decreased over time. Presence of dystonia before treatment initiation was the only identified predictor of worse residual GAS score. Greater severity of residual dystonia was associated with female gender and longer disease duration. CONCLUSION: Although patients with neurological form of WD compliant to de-coppering treatment had favorable disease outcome, a significant burden of residual neurological symptoms was observed after the long-term follow-up. Dystonia at disease onset was the only identified predictor of the worse long-term outcome.

Status dystonicus: predictors of outcome and progression patterns of underlying disease.

BACKGROUND: Status dystonicus (SD) is a rare, life-threatening disorder characterized by acute worsening of generalized dystonia. METHODS: This study was conducted to characterize the pathogenesis, clinical course, and prognosis of SD. We reviewed the records of six centers and analyzed them together with all the cases previously reported in the literature. RESULTS: Eighty-nine episodes occurring in 68 patients were studied. The majority of patients were males (64.7%), were <15 years of age (58.8%), and had secondary dystonia as the underlying condition (37.8%). The episodes were mainly characterized by tonic muscle spasms (68.5%), with phasic forms more common in secondary forms and among females. Almost all cases needed a multistaged approach, with surgery being the most successful strategy. Neurological conditions preceding the episode worsened in 16.2% of cases (ending in death in 10.3%). CONCLUSIONS: The course and outcome of SD is highly variable; male gender and prevalent tonic phenotype predict a poor outcome.

Genetic and phenotypic variability in adult patients with Niemann Pick type C from Serbia: single-center experience.

BACKGROUND: Niemann Pick type C is an autosomal recessive lysosomal storage disorder caused by mutations in NPC1 and NPC2 genes. It is a neuro-visceral disease with a heterogeneous phenotype. Clinical features depend on the age at onset. Visceral manifestations are more prominent in the early onset (infantile) form, while neuro-psychiatric symptoms are more prominent in the late disease onset (juvenile and adult forms). METHODS: A total number of 150 patients have been screened for changes in NPC1 and NPC2 gene at the Neurology Clinic, University Clinical Centre of Serbia in the period 2012-2020. Clinical data were extracted for patients with biallelic mutations. RESULTS: Fifteen patients carried biallelic mutations in the NPC1. Out of eight different reported NPC1 variants, four are novel (c.1204_1205TT>GC, p.F402A; c.2486T>G, p.L829R; c.2795+5 G>C; c.3722T>A, p.L1241*). The mean age at the disease onset was 20.3 ± 11.9 years with the average diagnostic delay of 7.7 ± 4.3 years. Movement disorders and psychiatric or cognitive disturbances were the most common initial symptoms (in 33% and 28% patients, respectively). The average age at the first neurological manifestation was 21 ± 12.0 years. At the last examination, eye movement abnormalities (vertical slow saccades or vertical supranuclear gaze palsy), and ataxia were present in all patients, while dystonia was common (in 78.6% of patients). Presence of c.2861C>T, p.S954L mutation in homozygous state was associated with older age at the neurological symptom onset. CONCLUSIONS: Clinical findings were in line with the expected, but the diagnostic delay was common. We hypothesize that the presence of c.2861C>T, p.S954L mutation may contribute to the phenotype attenuation.

Longitudinal clinical, cognitive, and neuroanatomical changes over 5 years in GBA-positive Parkinson's disease patients.

OBJECTIVE: To study the longitudinal disease course of Parkinson's disease (PD) patients with glucocerebrosidase (GBA) mutation (GBA-positive) compared to PD non-carriers (GBA-negative) along a 5-year follow-up, evaluating changes in clinical and cognitive outcomes, cortical thickness, and gray-matter (GM) volumes. METHODS: Ten GBA-positive and 20 GBA-negative PD patients underwent clinical, neuropsychological, and MRI assessments (cortical thickness and subcortical, hippocampal, and amygdala volumes) at study entry and once a year for 5 years. At baseline and at the last visit, each group of patients was compared with 22 age-matched healthy controls. Clinical, cognitive, and MRI features were compared between groups at baseline and over time. RESULTS: At baseline, GBA-positive and GBA-negative PD patients had similar clinical and cognitive profiles. Compared to GBA-negative and controls, GBA-positive patients showed cortical thinning of left temporal, parietal, and occipital gyri. Over time, compared to GBA-negative, GBA-positive PD patients progressed significantly in motor and cognitive symptoms, and showed a greater pattern of cortical thinning of posterior regions, and frontal and orbito-frontal cortices. After 5 years, compared to controls, GBA-negative PD patients showed a pattern of cortical thinning similar to that showed by GBA-positive cases at baseline. The two groups of patients showed similar patterns of subcortical, hippocampal, and amygdala volume loss over time. CONCLUSIONS: Compared to GBA-negative PD, GBA-positive patients experienced a more rapid motor and cognitive decline together with a greater, earlier and faster cortical thinning. Cortical thickness measures may be a useful tool for monitoring and predicting PD progression in accordance with the genetic background.

Quality of life in patients with treated and clinically stable Wilson's disease.

Health-related quality of life (HRQoL) in Wilson's disease (WD) has not been extensively studied. Therefore, the purpose of this cross-sectional study was to identify clinical and demographic factors influencing HRQoL in 60 treated, clinically stable patients with WD using a generic questionnaire, the Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36). The level of disability and grading of WD multisystemic manifestations were assessed by the Global Assessment Scale for WD (GAS for WD). The Mini Mental State Examination (MMSE) and the 21-item Hamilton Depression Rating Scale (HDRS) scoring were also applied by the same trained interviewers. Lower scores on the SF-36 domains were found in patients with neurological compared with those with a predominantly hepatic form of WD. The HRQoL of patients with WD and psychiatric symptoms was also lower than that of those without them. Finally, significant inverse correlations were obtained between the various SF-36 domains and all the following: period of latency from the first symptoms/signs appearance and treatment initiation, MMSE and HDRS scores, and different domains of the GAS for WD.

Perspectives on the pharmacological management of dystonia.

Introduction: Treatment of dystonia is particularly complex due to various etiologies and heterogeneous clinical manifestation, as well as different degrees of disability. In absence of causative treatment, all symptomatic therapy should be predominantly tailored to ameliorate those symptoms (motor and non/motor) that mostly affect patients' daily life and regular activities. Many different treatment options, including oral medications, neurosurgical interventions, physical and occupational therapy are available in treatment of dystonia.Areas covered: The aim of this perspective is to point out different possibilities in pharmacological management of dystonic movements. Due to pure clinical presentation, the authors concentrate mainly on the isolated dystonias, which are presented solely as dystonic movements. Combined and complex dystonias are not instructive due to compound clinical presentation and consequently, complicated treatment. The article is based on a literature search from sources including PubMed, the Cochrane Library, Web of Science, PiCarta, and PsycINFO.Expert opinion: Although dystonia therapy should be adapted according to the individual needs, severity, age, type, symptoms distribution and acceptable side-effect profile, certain principles should be followed to reach the optimal result. Furthermore, the authors believe that a better understanding of the pathophysiology of dystonia will bring with it the development of new and improved treatment approaches and medications.

NBIA Syndromes: A Step Forward from the Previous Knowledge.

A disturbed iron metabolism may damage brain and trigger disorders known as neurodegeneration with brain iron accumulation (NBIA). NBIAs are rare, inherited disorders in which responsible mutations affect the function of proteins that participate in tissue iron homeostasis. Accumulated iron, which may be recognized as a low signal intensity on T2-weighted MRI images, oftentimes points to a diagnosis. Recent genetic discoveries confirm that NBIA is not a homogenous group of diseases. Fifteen different NBIAs have been described to date; among these, autosomal recessive inheritance was reported in 13, and autosmal dominant and X-linked dominant inheritance in one disease, respectively. Among NBIAs, the most common is pantothenate kinase-associated neurodegeneration (PKAN-NBIA 1) (30%-50% of all NBIA cases), that occurrs as a consequence of the autosomal recessive mutation in PANK2 gene, followed by phospholipase 2-associated neurodegeneration (PLAN, NBIA 2), due to mutation in PLA2G6 gene, and mitochondrial membrane protein-associated neurodegeneration (MPAN) with the underlying C19orf12 mutation [Table 1]. NBIAs are characterized by complex motor presentations from early-onset degeneration and premature fatality to adult-onset parkinsonism and dystonia. Epileptic seizures, pyramidal signs, visual disorders, and cognitive deterioration can develop. NBIAs are often refractory to therapeutical strategies, although certain interventions may provide significant symptomatic relief in selected patients. In this review, we discuss the expanding clinical spectrum of these complex and rare syndromes, their genetic and imaging features, and potential therapeutical targets and strategies.

Changes of Phenotypic Pattern in Functional Movement Disorders: A Prospective Cohort Study.

Introduction: Functional movement disorders (FMD) refer to a group of movement disorders that present with clinical characteristics incongruent to those due to established pathophysiologic processes, as for example in the case of neurodegeneration or lesions. The aim of this study was to assess clinical features that contribute to the specific phenotypic presentations and disease course of FMD. Methods: The study consisted of 100 patients with FMD treated at Clinic for Neurology, Clinical Center of Serbia, who were longitudinally observed. Comprehensive clinical and psychiatric assessment was performed at the baseline, when initial FMD phenotype was defined. Follow-up assessment of phenotypic pattern over the time and clinical course was done after 3.2 ± 2.5 years at average. Results: We showed that 48% of FMD patients were prone to changes of phenotypic pattern during the disease course. Dystonia had tendency to remains as single and unchanged phenotype over the time (68.2%), while patients initially presented with Tremor, Gait disorder, Parkinsonism and Mixed phenotype were more susceptible to developing additional symptoms (62.5, 50, and 100%, respectively). Higher levels of somatoform experiences (p = 0.033, Exp(B) = 1.082) and higher motor severity (p = 0.040, Exp(B) = 1.082) at baseline assessment were associated with an increased likelihood of further enriching of FMD phenotype with additional functional symptoms. Also, these patients more frequently reported pain, and had higher scores on majority of applied psychiatric scales, together with more frequent presence of major depressive disorder. Conclusion: Results from this prospective study suggested tendency for progression and enrichment of functional symptoms in FMD patients over time. Besides functional core symptoms, other key psychological and physical features (like pain or multiple somatisations) were quite relevant for chronicity and significant dysability of FMD patients.

Clinical course of patients with pantothenate kinase-associated neurodegeneration (PKAN) before and after DBS surgery.

INTRODUCTION: Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with a progressive clinical course. In addition to symptomatic therapy, DBS has been increasingly recognized as a potential therapeutic strategy, especially in severe cases. Therefore, we wanted to report our experience regarding benefits of DBS in five PKAN cases in 3-year follow-up study. METHODS: Five genetically confirmed PKAN patients from Serbia underwent GPi-DBS. To assess clinical outcome, we reviewed medical charts and applied: Schwab and England Activities of Daily Living Scale (S&E), EQ-5D questionnaire for quality of life, Patient Global Impression of Improvement (GPI-I), Functional Independence Measure (FIM), Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), Barry Albright Dystonia Scale (BAD). Patients were evaluated in five visits: at the disease onset, 5 years after the onset, before surgery, 6 months and 14-36 months after the surgery. Improvement of 20% was accepted as significant. RESULTS: Overall, dystonia significantly improved after GPi-DBS at 6 and 14-36 months postoperatively, when assessed by the BFMDRS and BAD. However, two patients failed to improve considerably. Four patients reported improvement on GPI-I, while one remained unchanged. Three patients reported significant improvement, when assessed with S&E and FIM. EQ-5D showed the most prominent improvement in the domains of mobility and pain/discomfort. CONCLUSION: Three out of our five patients experienced beneficial effects of the GPi-DBS, in up to 36 months follow-up. Two patients who had not reached significant improvement had longer disease duration; therefore, it might be reasonable to recommend GPi-DBS as soon as dystonia became disabling.

Pharmacokinetic drug evaluation of opicapone for the treatment of Parkinson's disease.

INTRODUCTION: Opicapone (OPC) is a novel, potent, reversible, and purely peripheral third-generation COMT inhibitor, which provides an enhancement in levodopa (L-Dopa) availability. It represents adjunctive therapy for L-Dopa treated patients with PD and motor fluctuations. Areas covered: The purpose of this study was to evaluate pharmacokinetic of OPC for the treatment of PD. Expert commentary: Oral OPC exhibits linear, dose-dependent absorption. However, following concomitant ingestion of a high-fat, high-calorie meal, the maximum plasma concentration will be decreased. A once-daily bedtime administration of OPC 1 h after the last daily L-Dopa/AADCi, are considered to avoid any interaction during the L-Dopa absorption phase. There are no clinically relevant effects of age (in adults), renal impairment or race on the pharmacokinetics of OPC. OPC dose adjustment is not needed in patients with mild to moderate chronic hepatic impairment. Opicapone exhibits the lowest potential for cytotoxicity in comparison with other COMT inhibitors. It significantly decreases COMT activity, with half-life of COMT inhibition in human erythrocytes of 61.6 h and increases systemic exposure to L-Dopa. This provides an enhancement in L-Dopa availability that translates into clinical benefit for PD patients in terms of significant decrease of OFF periods and increase in ON-time without troublesome dyskinesia.