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Background/aim: In this study, we investigated the blink reflex (BR) after simultaneous and asynchronous stimulation of two trigeminal nerve branches. The objective was to characterize the physiology of trigeminal and facial circuits. Materials and methods: We performed three sets of experiments: recording BR response i. after supraorbital nerve stimulation (SON), after mental nerve stimulation (MN), and after simultaneous SON and MN stimulation (SON+MN) in 18 healthy individuals; ii. after MN (at an intensity eliciting BR response) preceding SON at various interstimulus intervals (ISIs) in seven healthy subjects; iii after MN (at sensory threshold) preceding SON at various ISIs. We compared the magnitudes of early and late responses. Results: The R1 amplitude after simultaneous SON+MN stimulation was greater than responses after single stimulation of the same branches. After simultaneous stimulations, the R2 and R2c areas under the curve (AUC) were smaller than the arithmetic sums of R2 and R2c AUC obtained after single stimulations. The second experiment provided a recovery excitability curve. In the third step, we obtained facilitation of R1 and inhibition of late responses. Conclusion: The SON+MN stimulation caused an increased R1 circuit excitability compared to the arithmetic sum of the single stimulations; however, magnitudes of late responses did not potentiate. Thus, we have provided evidence for R1 circuit enhancement by simultaneous stimulation in humans, whereas modulation of late responses exhibited a recovery curve similar to that shown for paired SON stimulation.
Subject(s)
Blinking , Electric Stimulation , Healthy Volunteers , Humans , Blinking/physiology , Adult , Male , Female , Electric Stimulation/methods , Trigeminal Nerve/physiology , Young Adult , ElectromyographyABSTRACT
OBJECTIVE: This study evaluated the isolated and combined effects of fear and PPS paradigms on SBR. METHOD: The prospective study was conducted with healthy participants. After stimulation of the right median nerve at the wrist, bilateral recordings were randomized under the following conditions: First experiment (with the right hand on the chair armrest): i. baseline recordings, ii. while watching fearful facial expressions from the Karolinska Emotional Faces battery (fear), iii. post-watching (post-fear), iv. while watching neutral facial expressions from the same battery (neutral), v. Immediately after viewing (post-neutral). Second experiment (right hand 2 cm away from the right eye, PPS): i. reference condition (PPS), ii. while watching fearful facial expressions (PPS-fear), iii. while watching neutral facial expressions (PPS-neutral). In each condition, SBR latency, area, duration, and amplitudes were measured and compared between conditions. RESULTS: We included 16 participants. SBR could be recorded in 11 (mean age:30.7 ± 5.2, F/M:5/6). First experiment: SBR amplitude was significantly reduced in fear condition (p = 0.008), and SBR area was reduced considerably in fear and post-fear conditions (p = 0.004) compared to the baseline. Second experiment: The SBR area was higher in the PPS (p = 0.009) compared to the baseline and even higher in the fearPPS compared to the PPS (p = 0.038). In neutral or PPS-neutral conditions, the area of the SBR did not change significantly. CONCLUSION: Fear suppressed SBR, but fear increased SBR when a threat stimulus was present. The findings were unrelated to habituation or attention, indicating cortical-amygdala-bulbar connections.
Subject(s)
Blinking , Facial Expression , Fear , Humans , Fear/physiology , Adult , Male , Female , Blinking/physiology , Prospective Studies , Median Nerve/physiology , Electromyography , Electric Stimulation , Young AdultABSTRACT
BACKGROUND: Responsive deep brain stimulation (rDBS) uses physiological signals to deliver stimulation when needed. rDBS is hypothesized to reduce stimulation-induced speech effects associated with continuous DBS (cDBS) in patients with essential tremor (ET). OBJECTIVE: To determine if rDBS reduces cDBS speech-related side effects while maintaining tremor suppression. METHODS: Eight ET participants with thalamic DBS underwent unilateral rDBS. Both speech evaluations and tremor severity were assessed across three conditions (DBS OFF, cDBS ON, and rDBS ON). Speech was analyzed using intelligibility ratings. Tremor severity was scored using the Fahn-Tolosa-Marin Tremor Rating Scale (TRS). RESULTS: During unilateral cDBS, participants experienced reduced speech intelligibility (P = 0.025) compared to DBS OFF. rDBS was not associated with a deterioration of intelligibility. Both rDBS (P = 0.026) and cDBS (P = 0.038) improved the contralateral TRS score compared to DBS OFF. CONCLUSIONS: rDBS maintained speech intelligibility without loss of tremor suppression. A larger prospective chronic study of rDBS in ET is justified. © 2024 International Parkinson and Movement Disorder Society.
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OBJECTIVE: To determine if the co-occurrence of apathy and impulse control disorders (ICDs) in Parkinson disease is dependent on instrument selection and assess the concurrent validity of three motivation measures by examining interrelationships between them. METHOD: Ninety-seven cognitively normal individuals with idiopathic Parkinson disease (PD) completed the Questionnaire for Impulsive-Compulsive Disorders in Parkinson Disease-Rating Scale (QUIP-RS) and three apathy measures: the Apathy Scale, Lille Apathy Rating Scale, and Item 4 of the Movement Disorder Society-Unified Parkinson Disease Rating Scale. RESULTS: Fifty (51.5%) participants were classified as apathetic on at least one measure, and only four individuals (4.3%) obtained clinically elevated scores on all three measures. The co-occurrence of apathy and ICD varied across measures. CONCLUSIONS: We observed a co-occurrence of apathy and ICDs in PD patients with each apathy instrument; however, limited concurrent validity exists across measures. This is important for future investigations into shared pathophysiology and the design of future clinical trials aimed at improving the early detection and treatment of these debilitating syndromes.
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OBJECTIVE: Cerebrotendinous xanthomatosis (CTX) is an inherited metabolic disorder characterized by progressive neurologic and extraneurologic findings. The aim of this retrospective, descriptive study was to explore the time of presentation and diagnosis, and to expand the phenotype and genotype of CTX, based on a nationwide and comprehensive series of patients in Turkey. METHODS: The demographic, clinical, biochemical and genotypic characteristics of the CTX patients were reviewed. Data on molecular analysis, age of onset and diagnosis, diagnostic delay, neurologic and extraneurologic symptomatology, results of plasma cholestanol levels, brain magnetic resonance imaging and electromyography at the time of diagnosis were reviewed. RESULTS: 100 confirmed CTX patients from 72 families were included. The mean age at diagnosis was 28.16 ± 14.28 years, and diagnostic delay was 18.39 ± 13.71 years. 36 patients were diagnosed in childhood. Frequency of intention tremor (p = 0.069), peripheral neuropathy (p = 0.234) and psychiatric manifestations (p = 0.396) did not differ between two groups, demonstrating the high rate in pediatric patients. Three adult patients showed a milder phenotype without neurologic involvement. Seven patients had normal plasma cholestanol levels despite neurological impairment. Sequencing of the CYP27A1 gene revealed 25 different variants, with a novel c.671_672del variant not previously described in literature. CONCLUSION: Based on the observations of this Turkish CTX cohort, it is emphasized that the true prevalence of CTX is probably underestimated and that it has a wide spectrum of clinical phenotypes even without neurological impairment. In children, abnormal cerebellar findings, peripheral neuropathy and psychiatric findings associated with intellectual disability have been suggested as warning signs to avoid diagnostic delay. In cases of clinical suspicion, molecular analysis is recommended despite normal plasma cholestanol levels, as severe neurologic involvement may occur in CTX patients without elevated cholestanol levels.
Subject(s)
Cholestanetriol 26-Monooxygenase , Cholestanol , Xanthomatosis, Cerebrotendinous , Humans , Xanthomatosis, Cerebrotendinous/genetics , Xanthomatosis, Cerebrotendinous/blood , Xanthomatosis, Cerebrotendinous/diagnosis , Male , Female , Adult , Turkey/epidemiology , Adolescent , Child , Cholestanetriol 26-Monooxygenase/genetics , Young Adult , Middle Aged , Cholestanol/blood , Retrospective Studies , Child, Preschool , Magnetic Resonance Imaging , Phenotype , Brain/pathology , Brain/diagnostic imaging , Brain/metabolism , Mutation , Genotype , Age of OnsetABSTRACT
To report the results of 'responsive' deep brain stimulation (DBS) for Tourette syndrome (TS) in a National Institutes of Health funded experimental cohort. The use of 'brain derived physiology' as a method to trigger DBS devices to deliver trains of electrical stimulation is a proposed approach to address the paroxysmal motor and vocal tic symptoms which appear as part of TS. Ten subjects underwent bilateral staged DBS surgery and each was implanted with bilateral centromedian thalamic (CM) region DBS leads and bilateral M1 region cortical strips. A series of identical experiments and data collections were conducted on three groups of consecutively recruited subjects. Group 1 (n = 2) underwent acute responsive DBS using deep and superficial leads. Group 2 (n = 4) underwent chronic responsive DBS using deep and superficial leads. Group 3 (n = 4) underwent responsive DBS using only the deep leads. The primary outcome measure for each of the 8 subjects with chronic responsive DBS was calculated as the pre-operative baseline Yale Global Tic Severity Scale (YGTSS) motor subscore compared to the 6 month embedded responsive DBS setting. A responder for the study was defined as any subject manifesting a ≥ 30 points improvement on the YGTSS motor subscale. The videotaped Modified Rush Tic Rating Scale (MRVTRS) was a secondary outcome. Outcomes were collected at 6 months across three different device states: no stimulation, conventional open-loop stimulation, and embedded responsive stimulation. The experience programming each of the groups and the methods applied for programming were captured. There were 10 medication refractory TS subjects enrolled in the study (5 male and 5 female) and 4/8 (50%) in the chronic responsive eligible cohort met the primary outcome manifesting a reduction of the YGTSS motor scale of ≥ 30% when on responsive DBS settings. Proof of concept for the use of responsive stimulation was observed in all three groups (acute responsive, cortically triggered and deep DBS leads only). The responsive approach was safe and well tolerated. TS power spectral changes associated with tics occurred consistently in the low frequency 2-10 Hz delta-theta-low alpha oscillation range. The study highlighted the variety of programming strategies which were employed to achieve responsive DBS and those used to overcome stimulation induced artifacts. Proof of concept was also established for a single DBS lead triggering bi-hemispheric delivery of therapeutic stimulation. Responsive DBS was applied to treat TS related motor and vocal tics through the application of three different experimental paradigms. The approach was safe and effective in a subset of individuals. The use of different devices in this study was not aimed at making between device comparisons, but rather, the study was adapted to the current state of the art in technology. Overall, four of the chronic responsive eligible subjects met the primary outcome variable for clinical effectiveness. Cortical physiology was used to trigger responsive DBS when therapy was limited by stimulation induced artifacts.
Subject(s)
Deep Brain Stimulation , Tics , Tourette Syndrome , Humans , Male , Female , Tourette Syndrome/therapy , Tourette Syndrome/complications , Tics/therapy , Tics/etiology , Deep Brain Stimulation/methods , Treatment Outcome , Severity of Illness IndexABSTRACT
Prader-Willi syndrome (PWS) is a complex, genetic disorder characterized by multisystem involvement, including hyperphagia, maladaptive behaviors and endocrinological derangements. Recent developments in advanced neuroimaging have led to a growing understanding of PWS as a neural circuit disorder, as well as subsequent interests in the application of neuromodulatory therapies. Various non-invasive and invasive device-based neuromodulation methods, including vagus nerve stimulation (VNS), transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and deep brain stimulation (DBS) have all been reported to be potentially promising treatments for addressing the major symptoms of PWS. In this systematic literature review, we summarize the recent literature that investigated these therapies, discuss the underlying circuits which may underpin symptom manifestations, and cover future directions of the field. Through our comprehensive search, there were a total of 47 patients who had undergone device-based neuromodulation therapy for PWS. Two articles described VNS, 4 tDCS, 1 rTMS and 2 DBS, targeting different symptoms of PWS, including aberrant behavior, hyperphagia and weight. Multi-center and multi-country efforts will be required to advance the field given the low prevalence of PWS. Finally, given the potentially vulnerable population, neuroethical considerations and dialogue should guide the field.
Subject(s)
Deep Brain Stimulation , Prader-Willi Syndrome , Transcranial Direct Current Stimulation , Transcranial Magnetic Stimulation , Vagus Nerve Stimulation , Humans , Prader-Willi Syndrome/therapy , Vagus Nerve Stimulation/methods , Vagus Nerve Stimulation/instrumentation , Transcranial Magnetic Stimulation/methods , Deep Brain Stimulation/methods , Deep Brain Stimulation/instrumentation , Transcranial Direct Current Stimulation/methodsABSTRACT
The blink reflex (BR) is integrated at the brainstem; however, it is modulated by inputs from various structures such as the striatum, globus pallidus, substantia nigra, and nucleus raphe magnus but also from afferent input from the peripheral nervous system. Therefore, it provides information about the pathophysiology of numerous peripheral and central nervous system disorders. The BR is a valuable tool for studying the integrity of the trigemino-facial system, the relevant brainstem nuclei, and circuits. At the same time, some neurophysiological techniques applying the BR may indicate abnormalities involving structures rostral to the brainstem that modulate or control the BR circuits. This is a state-of-the-art review of the clinical application of BR modulation; physiology is reviewed in part 1. In this review, we aim to present the role of the BR and techniques related to its modulation in understanding pathophysiological mechanisms of motor control and pain disorders, in which these techniques are diagnostically helpful. Furthermore, some BR techniques may have a predictive value or serve as a basis for follow-up evaluation. BR testing may benefit in the diagnosis of hemifacial spasm, dystonia, functional movement disorders, migraine, orofacial pain, and psychiatric disorders. Although the abnormalities in the integrity of the BR pathway itself may provide information about trigeminal or facial nerve disorders, alterations in BR excitability are found in several disease conditions. BR excitability studies are suitable for understanding the common pathophysiological mechanisms behind various clinical entities, elucidating alterations in top-down inhibitory systems, and allowing for follow-up and quantitation of many neurological syndromes.
Subject(s)
Dystonic Disorders , Hemifacial Spasm , Humans , Blinking , Peripheral Nervous System , Facial Pain , Reflex/physiologyABSTRACT
BACKGROUND AND AIMS: This study aimed to identify the clinical characteristics and electrodiagnostic subtypes of Guillain-Barré syndrome (GBS) in Istanbul. METHODS: Patients with GBS were prospectively recruited between April 2019 and March 2022 and two electrodiagnostic examinations were performed on each patient. The criteria of Ho et al., Hadden et al., Rajabally et al., and Uncini et al. were compared for the differentiation of demyelinating and axonal subtypes, and their relations with anti-ganglioside antibodies were analyzed. RESULTS: One hundred seventy-seven patients were included, 69 before the coronavirus disease 2019 pandemic (April 2019-February 2020) and 108 during the pandemic (March 2020-March 2022), without substantial changes in monthly frequencies. As compared with the criteria of Uncini et al., demyelinating GBS subtype diagnosis was more frequent according to the Ho et al. and Hadden et al. criteria (95/162, 58.6% vs. 110/174, 63.2% and 121/174, 69.5%, respectively), and less frequent according to Rajabally et al.'s criteria (76/174, 43.7%). Fourteen patients' diagnoses made using Rajabally et al.'s criteria were shifted to the other subtype with the second electrodiagnostic examination. Of the 106 analyzed patients, 22 had immunoglobulin G anti-ganglioside antibodies (14 with the axonal subtype). They had less frequent sensory symptoms (54.5% vs. 83.1%, p = 0.009), a more frequent history of previous gastroenteritis (54.5% vs. 22.9%, p = 0.007), and a more severe disease as compared with those without antibodies. INTERPRETATION: Serial electrodiagnostic examinations are more helpful for accurate subtype diagnosis of GBS because of the dynamic pathophysiology of the disease. We observed no significant increase in GBS frequency during the pandemic in this metropolis.
Subject(s)
Guillain-Barre Syndrome , Humans , Prospective Studies , Neural Conduction/physiology , Electrodiagnosis/methods , Gangliosides , AntibodiesABSTRACT
OBJECTIVE: We studied blink reflex (BR) and BR excitability recovery (BRER) in patients with hemifacial spasm (HFS) exhibiting different abnormal discharge patterns. We hypothesized that patients with groups of clonic or tonic burst activities appear later in the disease course and may have more excitability of the BR circuit at the brainstem compared to patients with isolated twitchings, which occur earlier. METHODS: We included 124 patients with botulinum toxin-naive HFS (mean age 50.6 ± 13.3 years) and 40 healthy subjects. We performed surface polymyography on facial muscles in patients and classified them according to the abnormal discharge pattern: isolated discharges, grouped bursts forming random sequences, tonic spasms, and a combination of these activities. Then, we recorded BR and BRER at 200, 600, and 1000 ms interstimulus intervals. We compared disease duration, R1 and R2 latencies, R2 area-under-the-curve (AUC), and BRER% (i) between healthy subjects and patients and (ii) among groups of patients with different abnormal discharge patterns. RESULTS: There were isolated discharges in 28 patients, grouped bursts forming random sequences in 42, and continuous muscle activity with tonic spasms in one. The remaining patients had combinations. Mean R1 and R2 latencies were significantly longer, and mean R2 AUC was significantly higher on the symptomatic side of patients compared to healthy subjects. The mean BRER was enhanced on both sides in patients than in healthy subjects (p < 0.001). However, it was similar among patient groups with different abnormal discharge patterns (p > 0.05). The mean disease duration in patients with isolated discharges was shorter (3.3 ± 2.0 years) than those with grouped bursts or tonic spasms (p = 0.002; Kruskal-Wallis test). CONCLUSION: Our study observed that excitability at the brainstem was similar in HFS patients with different abnormal discharge patterns, suggesting that the difference in discharge patterns in HFS may be due to a reason other than the difference in BR excitability.
Subject(s)
Hemifacial Spasm , Adult , Humans , Middle Aged , Blinking , Brain Stem , Facial MusclesABSTRACT
BACKGROUND AND OBJECTIVE: Rasmussen's encephalitis (RE) is a rare chronic neurological disorder, characterized by unilateral inflammation of the cerebral cortex, refractory focal epilepsy or epilepsia partialis continua, hemiparesis, and progressive cognitive decline. Interleukin-1 (IL-1) plays an important role in neuroinflammation as a key element in the activation of the inflammatory IL-1ß-IL-1 receptor type 1 (IL-1R1) axis. Anakinra, an IL-1 inhibitor, is successfully used in patients with new onset refractory status epilepticus and febrile infection-related epilepsy syndrome. METHODS AND RESULTS: We present 38-year-old male with RE having right-sided hemiparesis and continuous spasms being unresponsive to immune modulatory therapies like pulse steroid, intravenous immunoglobulin and anti-seizure drugs. After treatment with anakinra for three weeks, the continuous spasms almost completely subsided, and his muscle strength returned to normal. DISCUSSION: Anakinra may be considered as a treatment option in patients with RE and refractory seizures.
Subject(s)
Drug Resistant Epilepsy , Encephalitis , Male , Humans , Adult , Interleukin 1 Receptor Antagonist Protein/therapeutic use , Spasm , Interleukin-1 , Paresis , Magnetic Resonance ImagingABSTRACT
OBJECTIVE: There are reports of peripheral nerve and muscle involvement during or after coronavirus disease 2019 (COVID-19), even following a mild infection. Here, we aimed to analyze the objective findings regarding peripheral nerve, neuromuscular junction, and muscle function using electrophysiology in patients with a previous COVID-19 infection. METHODS: All consecutive patients with a history of COVID-19 were questioned for post-COVID-19 duration-related neurological complaints via Composite Autonomic Symptom Score-31 (COMPASS-31), modified Toronto Neuropathy score (mTORONTO), and Fatigue Severity Scale (FSS). Patients were dichotomized into two groups based on their scores in the questionnaire. Group 1 (patients with high scores in any area of the questionnaire) and Group 2 (patients with normal scores in all sections of the questionnaire). In the second step, Group 1 was invited to a preplanned hospital visit for electrophysiological analysis, including nerve conduction studies, repetitive nerve stimulation, needle electromyography (EMG), quantitative motor unit potential analysis (qMUP), and single fiber EMG. We included 106 patients in the study. According to the questionnaire, 38 patients constituted Group 1, and 68 formed Group 2. RESULTS: Of the 38 patients, 14 accepted and underwent preplanned electrophysiological examinations. Needle EMG revealed small, short, polyphasic MUPs with early recruitment, and qMUP analysis demonstrated an increased percentage of polyphasic potentials in three patients. The examinations in other patients were unremarkable. CONCLUSIONS: The high prevalence of complaints and objective myopathic findings in our cohort implicated the role of muscle involvement in the post-COVID-19 duration. Considering the socioeconomic and psychological burden of the post-COVID-19 duration among individuals and societies, a better understanding of the symptoms and myopathy is warranted.
Subject(s)
COVID-19 , Muscular Diseases , Humans , Muscle, Skeletal , Prevalence , ElectromyographyABSTRACT
OBJECTIVE: This study aims to clinically evaluate the impulse control disorders (ICDs) encountered in treating Parkinson's disease. METHOD: This is a retrospective analysis between 2010 and 2022. We retrieved the medical records of all patients diagnosed with idiopathic Parkinson's disease. The demographic and clinical findings were recorded. ICDs constituted a specific item in the examination, and each one (compulsive shopping, compulsive eating, pathological gambling, hypersexuality, punding, dopamine dysregulation syndrome, and hobbyism) was noted separately. RESULTS: In the study period, we identified 1824 patients (56.2% men, n = 1025). The mean age was 70.5 ± 11.9 years. In the cohort, 128 (7%) patients with Parkinson's disease had one or more ICDs. The ICDs were compulsive shopping, punding/hobbyism, compulsive eating, hypersexuality, pathological gambling, and dopamine dysregulation syndrome. When we compared patients with and without ICDs, patients with ICDs were younger (p ≤ 0.001), and the men/women ratio was higher in this group with ICDs. Although the mean daily pramipexole dose was higher in patients with ICDs, mean daily long-acting pramipexole dose was only 1.4 ± 0.92 mg/day. CONCLUSION: The significant findings in this study were (i) the lower frequency of ICDs (7%); (ii) the common occurrence of compulsive shopping, punding/hobbyism, and compulsive eating; and (iii) the development of ICDs under relatively lower doses of pramipexole. We suggest that ICDs in Parkinson's disease should be associated with a personal trait with dopamine agonists, and potential electrophysiological or genetic markers of this trait warrant further analysis to avoid treatment in these patients.
Subject(s)
Disruptive, Impulse Control, and Conduct Disorders , Parkinson Disease , Male , Humans , Female , Middle Aged , Aged , Aged, 80 and over , Parkinson Disease/complications , Parkinson Disease/drug therapy , Parkinson Disease/epidemiology , Dopamine , Pramipexole/therapeutic use , Retrospective Studies , Disruptive, Impulse Control, and Conduct Disorders/epidemiology , Disruptive, Impulse Control, and Conduct Disorders/etiology , Dopamine Agonists/adverse effects , SyndromeABSTRACT
BACKGROUND: Deep brain stimulation (DBS) is a highly efficient, evidence-based therapy to alleviate symptoms and improve quality of life in movement disorders such as Parkinson's disease, essential tremor, and dystonia, which is also being applied in several psychiatric disorders, such as obsessive-compulsive disorder and depression, when they are otherwise resistant to therapy. SUMMARY: At present, DBS is clinically applied in the so-called open-loop approach, with fixed stimulation parameters, irrespective of the patients' clinical state(s). This approach ignores the brain states or feedback from the central nervous system or peripheral recordings, thus potentially limiting its efficacy and inducing side effects by stimulation of the targeted networks below or above the therapeutic level. KEY MESSAGES: The currently emerging closed-loop (CL) approaches are designed to adapt stimulation parameters to the electrophysiological surrogates of disease symptoms and states. CL-DBS paves the way for adaptive personalized DBS protocols. This review elaborates on the perspectives of the CL technology and discusses its opportunities as well as its potential pitfalls for both clinical and research use in neuropsychiatric disorders.
Subject(s)
Deep Brain Stimulation , Mental Disorders , Parkinson Disease , Humans , Deep Brain Stimulation/methods , Quality of Life , Brain , Mental Disorders/therapy , Parkinson Disease/therapyABSTRACT
BACKGROUND: Here, we aimed to investigate the roles of long-term potentiation-like (LTP-like) plasticity using intermittent theta burst (iTBS) protocol and resting motor threshold (rMT) in the differential diagnosis of Alzheimer's disease (AD), diffuse dementia with Lewy bodies (DLB) and frontotemporal dementia (FTD). METHOD: We enrolled 21 subjects with AD, 28 subjects with DLB, 14 subjects with FTD, and 33 elderly subjects with normal cognitive functions into the study. We recorded rMT and percentage amplitude change of motor evoked potentials (MEPs) after the iTBS protocol in each group. RESULTS: In patients with AD and DLB, the percentage amplitude change of MEPs, and rMTs were significantly lower than in healthy subjects. However, no significant difference was observed in individuals with FTD. CONCLUSION: Our findings showed that transcranial magnetic stimulation measures, particularly rMTs and LTP-like plasticity, may be potential biomarkers to distinguish between different dementia subtypes. Impaired motor cortical excitability and synaptic plasticity were more prominent in AD and DLB than in FTD. This aligns with the evidence that cortical motor networks are usually spared in FTDs in early-to-middle stages.
Subject(s)
Alzheimer Disease , Cortical Excitability , Frontotemporal Dementia , Lewy Body Disease , Pick Disease of the Brain , Aged , Humans , Frontotemporal Dementia/diagnosis , Alzheimer Disease/diagnosis , Lewy Body Disease/diagnosis , Transcranial Magnetic StimulationABSTRACT
We hypothesized that "long latency reflexes" (LLRs), associated segmental reflex (SR), and mixed nerve silent periods (MnSPs) recorded on the distal upper extremity muscles would behave differently in patients with cervical dystonia and focal hand dystonia. We enrolled patients with cervical dystonia, generalized dystonia, focal hand dystonia, and healthy individuals. We recorded SR, LLRs, and MnSPs. The mean amplitude of SR on the affected side of focal hand dystonia was significantly lower (p = 0.010). The parameters related to LLRs and MnSPs were not different between groups. We suggest, using SR, LLRs, and MnSPs, we could not show an electrophysiological signature specific to dystonia.
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INTRODUCTION: In polycythemia vera (PV) patients undergoing phlebotomy, iron deficiency (ID) may develop. ID has been linked to restless legs syndrome (RLS), and in one study, 29.6% of PV patients had RLS. We aimed to evaluate the frequency of RLS in PV and to evaluate factors that might play a role in RLS development among PV and essential thrombocythemia (ET) patients. METHODS: We consecutively included PV cases as the patient group, and ET and ID patients and healthy subjects (HSs) were included as controls. Those with conditions that could lead to RLS were excluded. All subjects were questioned according to the diagnostic criteria of the International Restless Legs Syndrome Study Group. RESULTS: Twenty-seven PV, 23 ET, and 22 ID patients and 23 HSs were included. RLS was detected in 25.9%, 34.8%, and 45.5% of PV, ET, and ID patients, respectively. None of the HSs had RLS. In univariate analysis, interferon-α and anagrelide use, magnesium levels, and the Leeds assessment of neuropathic symptoms and signs (LANSS) scores had a significant impact on RLS in PV and ET patients (p = 0.014, p = 0.032, p = 0.036, and p = 0.003, respectively). CONCLUSION: RLS was more common among PV and ET patients than HSs, which was irrespective to the iron status. RLS was more frequent in ET patients than that observed in PV cases, indicating that ID may not be the only causative factor for RLS development in PV. Further prospective studies are needed to determine the prevalence and risk factors of RLS developing in PV and ET.
Subject(s)
Iron Deficiencies , Polycythemia Vera , Restless Legs Syndrome , Humans , Polycythemia Vera/complications , Polycythemia Vera/epidemiology , Polycythemia Vera/diagnosis , Cross-Sectional Studies , Restless Legs Syndrome/epidemiology , Restless Legs Syndrome/etiology , PrevalenceABSTRACT
OBJECTIVE: In parkinsonian syndromes, presentations other than current diagnostic criteria are considered atypical findings. Our goal was to identify and describe the frequency and features of uncommon manifestations of atypical parkinsonian syndromes within our group. METHODS: We retrospectively retrieved the medical records of all patients admitted to our clinic with parkinsonism between January 2011 and January 2022. We only included patients with atypical parkinsonian syndromes, in which the diagnosis was based on current clinical criteria. We retrospectively analyzed neurological, psychiatric, radiological, and electrophysiological characteristics. Typical and atypical features were classified according to the current clinical criteria and previous reports. RESULTS: We determined 51 patients with atypical parkinsonian syndromes; 46 were included, whereas five were excluded due to insufficient follow-up. The probable diagnoses were multiple system atrophy (MSA, n = 19), dementia with Lewy bodies (DLB, n = 10), frontotemporal dementia (FTD, n = 10), corticobasal syndrome (CBS, n = 3), progressive supranuclear palsy (PSP, n = 4). The prevalence of atypical findings was similar among different types of atypical parkinsonian syndromes (p = 0.847). Atypical findings were eyelid myoclonus, double vision in MSA; ataxia, myoclonus, and a typical hummingbird sign on MRI in DLB; pyramidal findings and family history in FTD; early onset, family history, and onset with psychiatric findings in PSP-like phenotype. Genetic causes were identified in the FTD-like phenotype with pyramidal findings, whereas symptom onset was early with myoclonus in the PSP-like phenotype. CONCLUSION: Atypical findings such as abnormal saccades, myoclonus, and ataxia may be a part of degenerative syndromes. However, family history, onset at an earlier age, and specific neurological findings suggest genetic syndromes.