Head Tremor Research Articles

Dystonic head tremor secondary to neurocysticercosis

Dystonic head tremor secondary to neurocysticercosis

Isolated Cervical Dystonia: Diagnosis and Classification.

This document presents a consensus on the diagnosis and classification of isolated cervical dystonia (iCD) with a review of proposed terminology. The International Parkinson and Movement Disorder Society Dystonia Study Group convened a panel of experts to review the main clinical and diagnostic issues related to iCD and to arrive at a consensus on diagnostic criteria and classification. These criteria are intended for use in clinical research, but also may be used to guide clinical practice. The benchmark is expert clinical observation and evaluation. The criteria aim to systematize the use of terminology as well as the diagnostic process, to make it reproducible across centers and applicable by expert and non-expert clinicians. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations, which are incorporated into the current criteria. Three iCD presentations are described in some detail: idiopathic (focal or segmental) iCD, genetic iCD, and acquired iCD. The relationship between iCD and isolated head tremor is also reviewed. Recognition of idiopathic iCD has two levels of certainty, definite or probable, supported by specific diagnostic criteria. Although a probable diagnosis is appropriate for clinical practice, a higher diagnostic level may be required for specific research studies. The consensus retains elements proven valuable in previous criteria and omits aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of iCD expands, these criteria will need continuous revision to accommodate new advances. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

INVESTIGATING BLOOD LACTATE CONCENTRATION AS A PROGNOSTIC INDICATOR FOR BIRDS PRESENTING WITH BREVETOXICOSIS: 2020-2021.

Large blooms of the dinoflagellate Karenia brevis cause annual harmful algal bloom events, or "red tides" on Florida's Gulf Coast. Each year, the Clinic for the Rehabilitation of Wildlife (CROW) is presented with hundreds of cases of aquatic birds that exhibit neurologic clinical signs due to brevetoxicosis. Double-crested cormorants (Phalacrocorax auratus) are the most common species seen, and typically present with a combination of ataxia, head tremors, knuckling, and/or lagophthalmos. Blood lactate levels are known to increase in mammals for a variety of reasons, including stress, hypoxia, sepsis, and trauma, but there is limited literature on blood lactate values in avian species. The objective of this study was to determine the prognostic value of blood lactate concentration on successful rehabilitation and release of birds presenting with clinical signs consistent with brevetoxicosis. Blood lactate levels were collected on intake, the morning after presentation and initial therapy, and prior to disposition (release or euthanasia) from 194 birds (including 98 cormorants) representing 17 species during the 2020-2021 red tide season. Overall, mean blood lactate at intake, the morning after intake, and predisposition was 2.9, 2.8, and 3.2 mmol/L, respectively, for released birds across all species (2.9, 2.9, and 3.2 mmol/L for released cormorants); 3.4, 3.4, and 6.5 mmol/L for birds that died (4.0, 3.5, and 7.9 mmol/L for cormorants that died); and 3.1, 3.5, and 4.7 mmol/L for birds that were euthanized (3.5, 4.7, and 4.9 mmol/L for cormorants that were euthanized). On average, birds that died or were euthanized had an elevated lactate at all time points as compared to those that were released, but these results were not statistically significant (P = 0.13). These results indicate that blood lactate levels do not appear to be useful as a prognostic indicator for successful release of birds, including double-crested cormorants, affected by brevetoxicosis.

Validation of a guideline to reduce variability in diagnosing cervical dystonia

BackgroundCervical dystonia is characterized by a variable pattern of neck muscle involvement. Due to the lack of a diagnostic test, cervical dystonia diagnosis is based on clinical examination and is therefore subjective. The present work was designed to provide practical guidance for clinicians in confirming or refuting suspected cervical dystonia.MethodsParticipants were video recorded according to a standardized protocol to assess 6 main clinical features possibly contributing to cervical dystonia diagnosis: presence of repetitive, patterned head/neck movements/postures inducing head/neck deviation from neutral position (item 1); sensory trick (item 2); and red flags related to conditions mimicking dystonia that should be absent in dystonia (items 3–6). Inter-/intra-rater agreement among three independent raters was assessed by k statistics. To estimate sensitivity and specificity, the gold standard was cervical dystonia diagnosis reviewed at each site by independent senior neurologists.ResultsThe validation sample included 43 idiopathic cervical dystonia patients and 41 control subjects (12 normal subjects, 6 patients with isolated head tremor, 4 with chorea, 6 with tics, 4 with head ptosis due to myasthenia or amyotrophic lateral sclerosis, 7 with orthopedic/rheumatologic neck diseases, and 2 with ocular torticollis). The best combination of sensitivity and specificity was observed considering all the items except for an item related to capability to voluntarily suppress spasms (sensitivity: 96.1%; specificity: 81%).ConclusionsAn accurate diagnosis of cervical dystonia can be achieved if, in addition to the core motor features, we also consider some clinical features related to dystonia mimics that should be absent in dystonia.

Risk factors of social anxiety in patients with essential tremor.

To study the risk factors of social anxiety (SA) in essential tremor (ET) patients. Motor, cognition, and SA were evaluated using the Fahn-Tolosa-Marin Tremor Rating Scale (FTMTRS), Mini-Mental State Examination (MMSE), and Liebowitz Social Anxiety Scale (LSAS) for each subject. The potential risk factors of SA in ET were analyzed using univariate analysis. A total of 80 ET patients and 85 healthy controls completed the evaluation. The LSAS evaluation showed that the prevalence of SA in the ET group was 48.8%, higher than that in controls (12.9%, P < 0.001). Female (OR = 4.959, P = 0.014), younger age (OR = 4.172, P = 0.037), and head tremor (OR = 4.707, P = 0.025) were risk factors of SA among ET patients. SA is prevalent in patients with ET. Risk factors, such as female sex, age, and head tremor, should be considered for the prevention and intervention of SA in ET patients.

Opsoclonus-myoclonus syndrome associated with pancreatic neuroendocrine tumor: a case report

BackgroundOpsoclonus-myoclonus syndrome (OMS) is a rare, immune-mediated neurological disorder. In adults, the pathogenesis can be idiopathic, post-infectious or paraneoplastic, the latter etiology belonging to the ever-expanding group of defined paraneoplastic neurological syndromes (PNS). In contrast to other phenotypes of PNS, OMS cannot be ascribed to a single pathogenic autoantibody. Here, we report the first detailed case of paraneoplastic, antibody-negative OMS occurring in association with a pancreatic neuroendocrine tumor (pNET).Case presentationA 33-year-old female presented with a two-week history of severe ataxia of stance and gait, dysarthria, head tremor, myoclonus of the extremities and opsoclonus. Her past medical history was notable for a metastatic pancreatic neuroendocrine tumor, and she was subsequently diagnosed with paraneoplastic opsoclonus-myoclonus syndrome. Further workup did not reveal a paraneoplastic autoantibody. She responded well to plasmapheresis, as she was refractory to the first-line therapy with corticosteroids.ConclusionsThis case expands current knowledge on tumors associated with paraneoplastic opsoclonus-myoclonus syndrome and the age group in which it can occur. It further adds evidence to the effectiveness of plasmapheresis in severe cases of opsoclonus-myoclonus syndrome with a lack of response to first-line therapy.

A Case Report of Acupotomy and Herbal Medicine Treatment for Patient with Essential Head Tremor

A Case Report of Acupotomy and Herbal Medicine Treatment for Patient with Essential Head Tremor

Exploring the heterogeneous morphometric data in essential tremor with probabilistic modelling

Essential tremor (ET) is a prevalent movement disorder characterized by marked clinical heterogeneity. Here, we explored the morphometric underpinnings of this cross-subject variability on a cohort of 34 patients with right-dominant drug-resistant ET and 29 matched healthy controls (HCs). For each brain region, group-wise morphometric data was modelled by a multivariate Gaussian to account for morphometric features’ (co)variance.No group differences were found in terms of mean values, highlighting the limits of more basic group comparison approaches. Variance in surface area was higher in ET in the left lingual and caudal anterior cingulate cortices, while variance in mean curvature was lower in the right superior temporal cortex and pars triangularis, left supramarginal gyrus and bilateral paracentral gyrus. Heterogeneity further extended to the right putamen, for which a mixture of two Gaussians fitted the ET data better than a single one.Partial Least Squares analysis revealed the rich clinical relevance of the ET population’s heterogeneity: first, increased head tremor and longer symptoms’ duration were accompanied by broadly lower cortical gyrification. Second, more severe upper limb tremor and impairments in daily life activities characterized the patients whose morphometric profiles were more atypical compared to the average ET population, irrespective of the exact nature of the alterations.Our results provide candidate morphometric substrates for two different types of clinical variability in ET. They also demonstrate the importance of relying on analytical approaches that can efficiently handle multivariate data and enable to test more sophisticated hypotheses regarding its organization.

Cerebellar abiotrophy in an Icelandic horse

BackgroundCerebellar abiotrophy (CA) is an uncommon hereditary neurodegenerative disorder affecting the cerebellar Purkinje cells. Equine CA has been reported in several breeds, but a genetic etiology has only been confirmed in the Arabian breed, where CA is caused by an autosomal recessive mutation.Case presentation.Clinical and histological findings consistent with CA are reported in an 8.5-month-old Icelandic filly. The filly showed a perceived sudden onset of marked head tremor, incoordination, ataxia, lack of menace response and a broad-based stance. Cerebrospinal fluid, hematological and biochemical findings were all within the normal range, ruling out several differential diagnoses. Post mortem histopathological examination revealed Purkinje cell degeneration accompanied by astrogliosis. Assessment of the filly’s pedigree revealed that its parents shared a common ancestor.ConclusionsTo the authors’ knowledge, this is the first report of CA in the Icelandic breed. The identification of a common parental ancestor makes autosomal recessive inheritance of CA in this filly possible, but this would need to be confirmed by further studies. Veterinarians and breeders working with Icelandic horses should be aware of this condition and report suspected cases in order to support genetic investigation.

Adaptive multi symptoms control of Parkinson's disease by deep reinforcement learning

Parkinson's disease (PD) is one of the really frequent disorders, with hand and head tremors and rigidity being the most common sequelae. Deep brain stimulation (DBS) is a common treatment used to alleviate the symptoms of this disease. This work investigates an ultra-local model (ULM) based on a sliding mode observer (SMO) to simultaneously reduce hand tremor and rigidity. specifically, a deep deterministic policy gradient (DDPG) controller is adaptively designed in the current study to reduce observer estimation error and improve the nonlinear dynamic features of a central neural network (CNN). The DDPG is designed with an actor that produces policy demands and a critic that measures the effectiveness of the actor’s policy orders. The offered methodology employs a DDPG-based mechanism to compensate for the shortcomings of the ULM-based SMO. In the present mechanism, training of the weight values of both networks (actor and critic) is by the gradient descent way that relies on the tremor fault's reward return. Finally, the following methodology is analyses by computer simulation in a variety of contexts (robustness and controller performance) and compared to current practices to prove the benefits and adaptability of the procedure with varied models and patients. Additionally, the controllers are implemented in the hardware-in-the-loop (HiL) simulations testbed to validate the performance of the developed scheme's profitability from a realistic perspective.

Locus coeruleus degeneration and cerebellar gray matter changes in essential tremor.

The pathophysiology of essential tremor (ET) is not fully understood, and studies suggest pathological changes mainly occur in the cerebellum and locus coeruleus (LC). Fifty-three ET patients, including 30 patients with head tremor (h-ET), 23 patients without head tremor (nh-ET), 71 age and education matched healthy controls (HCs) were enrolled. All participants underwent Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and T1 scans on a 3-Tesla MR system. Next, we assessed the relationship between the contrast-to-noise ratio of LC (CNRLC) and the score of The Essential Tremor Rating Assessment Scale (TETRAS) and cerebellum gray matter (GM) volume. Significant difference of CNRLC was found between ET and HC groups. The CNRLC of ET groups is lower than the HC group (p = 0.031). Subgroup analysis showed that the CNRLC in nh-ET was significantly lower than HCs (p = 0.016). Compared to HCs, h-ETs showed marked atrophy in the cerebellum: the vermis IV-V and lobule VI (GRF corrected, p < 0.05). A significant negative correlation was found between CNRLC and the vermis lobule IV-V in h-ETs (r = -0.651, p < 0.001). No significant correlation was found between CNRLC and TETRAS scores. The LC and the cerebellum might both involve in the pathophysiology of ET. LC evaluation using NM-MRI might be an effective tool for us to explore the pathophysiology of ET further.

S3196 Wilson Disease in a U.S. Navy Pilot: Delayed Diagnosis With Drastic Career Implications

Introduction: Wilson disease is an autosomal recessive genetic disorder of the intracellular copper transport ATP7B leading to impaired copper excretion and subsequent accumulation in the liver, brain and cornea. Index symptoms vary widely and include neurologic and psychiatric abnormalities. The wide array of subtle symptoms often lead to significant delays in diagnosis and thus prognostic implications for patients diagnosed with this rare disease. In the Armed Forces, the diagnosis and clinical sequelae can have drastic career implications especially when neurologic sequelae are resistant to treatment. Case Description/Methods: A 28 year old US Navy pilot male presented to behavioral health clinic with complaint of depressed mood. He was diagnosed with major depressive disorder which was resistant to traditional treatment for over a year. He developed fasciculations of his neck and arms which was associated with initiation of an SSRI. When he had difficulty landing an aircraft due these progressive symptoms, he was deemed incapable of flight. He later required admission for suicidal ideations. He had several concerning incidents occur including driving over a median and through several red lights. Neurology was consulted and examination showed hyperkinetic movements of his extremities with head and voice tremors. Lab work revealed ALT 52 and AST 48 and later, a ceruloplasmin of 6.7. A slit lamp exam was performed revealing Kayser-Fleischer rings. MRI brain showed abnormal T2 signal within the basal ganglia and midbrain consistent with copper deposition. MRI liver was consistent with cirrhosis. A liver biopsy confirmed the diagnosis of Wilson disease with cirrhosis. He was started on trientene and zinc for chelation and his mood markedly improved. However, his neurologic abnormalities have persisted despite ongoing therapy for over 4 years, permanently ending his piloting career. Discussion: Our case highlights the importance of careful clinical consideration in patients presenting with psychiatric complaints. We aim to highlight this patient’s response to therapy, and lack thereof, as the range of patient response can be quite broad. The majority of patient’s have significant or even total resolution of symptoms. Our patient had significant improvement in depression after chelation therapy but his neurologic symptoms did not recover. Regrettably, the patient’s Navy pilot career was brought to an early close given the severity of his symptoms and lack of response and thus, inability to perform as an aviator.

Diagnosis and Treatment of Essential Tremor.

Essential tremor is a chronic, progressive syndrome that primarily presents with an action tremor involving the arms and hands. This article reviews the history and physical examination features pertinent for diagnosis, differential diagnoses, and treatments and approaches for optimal control of symptoms. Essential tremor is a syndrome with symptoms extending beyond tremor to involve disturbances in gait, speech, cognition, and mood. Although the new guidelines on the definition and biaxial classification scheme have provided clarity, some tremor experts have critiqued the recently coined term essential tremor plus. For treatment, new orthotic devices and peripheral stimulation devices are now available in addition to pharmacologic and surgical options. Essential tremor has a rich clinical phenomenology with many subtleties and nuances. A detailed history with open-ended questions and focused questions encompassing medical history, social history, and family history is key for establishing the diagnosis. The presence of bilateral action tremor for 3 years and absence of isolated head and voice tremor and absence of task- and position-dependent tremor are necessary for diagnosis. Dystonic tremor, Parkinson disease tremor, physiologic tremor, and drug-induced tremor are common differential diagnoses. Differentiating these tremor disorders from essential tremor based on phenomenology and physical examination alone could be challenging; thus, clinicians should seek additional clues from a detailed history. Treatment could begin with noninvasive and nonpharmacologic therapies, especially in mild cases. As the severity increases, they can advance stepwise to include pharmacotherapies and surgical interventions. With the growing recognition that essential tremor is not a monosymptomatic disorder, management should involve a multidisciplinary team. Furthermore, treatment selection should be based on shared decision making between patients and providers that gives due consideration to severity of symptoms, level of functional disability, impact on social interactions, patient preferences, and patient expectations.

Cerebellar Abiotrophy in Australian Working Kelpies Is Associated with Two Major Risk Loci.

An autosomal recessive form of inherited cerebellar abiotrophy (CA) that is characterized by a degeneration of Purkinje and granule cells in the cerebellar cortex occurs in the Australian working kelpie dog breed. The clinical signs of CA include ataxia, head tremor, motor in-coordination, wide-based stance, and high-stepping gait. Investigation of clinical and pathological features indicated two closely related diseases with differences in age of onset. A genome-wide association study on 45 CA affected and 290 normal healthy Kelpies identified two significantly associated loci, one on CFA9 and a second on CFA20. Dogs homozygous for the risk haplotype on CFA20 (23 dogs) show clinical signs before ten weeks of age. Missense variants in the sixth exon of disruptor of telomeric silencing 1-like (DOT1Lp.R200Q) and in the only exon of Leucine Rich Repeat And Ig Domain Containing 3 (LINGO3p.R359C), both on CFA20, segregate with the associated risk marker which has incomplete penetrance (42%). Affected dogs homozygous for the risk haplotype on CFA9 have later onset ataxia. A missense variant in exon 5 of Vacuole Membrane Protein 1 (VMP1 p.P160Q) on CFA9 segregates as a fully penetrant Mendelian recessive with later-onset CA. Across mammals, the variety of causative loci so far identified as influencing cerebellar disorders reinforces the complexity of the pathways that contribute to cerebellar development and function, and to the pathophysiological mechanisms that may lead to cerebellar ataxia.

Bolu Abant İzzet Baysal Üniversitesi Nöroloji Kliniğinde Botulinum Toksin Uygulamaları Deneyimleri

Aim: The aim of this study was to evaluate the effects of different clinical applications of BoNT-A as hemifacial spasm, blepharospasm, cervical dystonia, bruxism, head tremor and spasticity in stroke, Multiple Sclerosis (MS), spinal trauma, hereditary spastic paraplegia, cerebral palsy, and chronic migraine. &#x0D; Material and Methods: In this retrospective study, which was conducted between January 2019 and December 2021, 79 patients with movement disorders, spasticity, and chronic migraine monitored in our clinic and whose BoNT-A injections were applied were included. The diagnosis and treatment, side effects encountered in therapy, follow-up during the treatment, and the response to the treatment evaluated subjectively by patients were discussed.&#x0D; Results: The improvement in patients' response to treatment was subjectively reported by themselves. The improvement in the response of the patients to the treatment subjectively stated that improvement of 60% and above was taken as good, improvement between 59-40% moderate, and improvement of 39% and below bad. Accordingly, 78.94% of the patients subjectively stated improvement as good, 13.15% as moderate, and 7.89% as bad. Although the incidence of complications was 9.21%, these side effects were mild and transient in all of the patients and did not cause any of the patients to discontinue the treatment.&#x0D; Conclusion: The results were statistically significant and consistent with the literature. This study supports the fact that botulinum toxin therapy is effective and safe for HS, BS, cervical dystonia, spasticity, bruxism, head tremor, and chronic migraine.

Does Head Tremor Predict Postural Instability After Bilateral Thalamic Stimulation in Essential Tremor?

Essential tremor (ET) may present with head tremor (HT), of presumed cerebellar nature. Deep brain stimulation (DBS) targeting the ventral intermediate (Vim) nucleus of the thalamus is a highly effective therapy for medication-refractory ET. However, stimulation-related side effects may include cerebellar abnormalities, such as postural instability. This retrospective cohort study evaluated the risk of post-Vim DBS postural instability (primary outcome measure) in patients with versus without head tremor (HT vs. nHT). The primary outcome measure, namely post-DBS postural instability, was assessed in both groups using a Wilcoxon rank sum t-test. The time to postural instability was determined using Cox proportional hazards regression analysis adjusted for age and sex. Out of 30 patients analyzed during the follow up period, there was similar postural instability detected in HT (9/14, 64%) and nHT patients (11/16, 69%) at 24 months post-Vim DBS (p=0.82), adjusted hazard ratio[aHR]=0.82, p=0.69). These data suggest that the presence or absence of HT does not have an impact on postural instability after bilateral Vim DBS in patients with ET.

From null to midline: changes in head posture do not predictably change head tremor in cervical dystonia.

A common view is that head tremor (HT) in cervical dystonia (CD) decreases when the head assumes an unopposed dystonic posture and increases when the head is held at midline. However, this has not been examined with objective measures in a large, multicenter cohort. For 80 participants with CD and HT, we analyzed videos from examination segments in which participants were instructed to 1) let their head drift to its most comfortable position (null point) and then 2) hold their head straight at midline. We used our previously developed Computational Motor Objective Rater (CMOR) to quantify changes in severity, amplitude, and frequency between the two postures. Although up to 9% of participants had exacerbated HT in midline, across the whole cohort, paired t-tests reveal no significant changes in overall severity (t = -0.23, p = 0.81), amplitude (t = -0.80, p = 0.43), and frequency (t = 1.48, p = 0.14) between the two postures. When instructed to first let their head drift to its null point and then to hold their head straight at midline, most patient's changes in HT were below the thresholds one would expect from the sensitivity of clinical rating scales. Counter to common clinical impression, CMOR objectively showed that HT does not consistently increase at midline posture in comparison to the null posture.

Clinical Features, Neuroimaging, and Levodopa-Responsiveness in Holmes' Tremor: A Video-Based Case-Series with a Review of the Literature.

Holmes' tremor (HT) is a low-frequency tremor characterized by a combination of rest, posture, and action components. We are reporting the clinical features, neuroimaging findings, and levodopa responsiveness in 12 patients with HT. The majority of the patients were male (11/12). Dystonia was observed in 10 patients and the remaining two patients had head tremor, a "forme-fruste" of cervical dystonia. The underlying etiologies were vascular (n=8), head trauma (n=2), and tumor resection (n=2). Neuroimaging showed isolated involvement of the midbrain in four, thalamus in two, and basal ganglia and cerebellum in one patient each. A combination of the lesion (thalamus and cerebellum=2; cerebellopontine angle=1, and cortical/subcortical=1) was present in four patients. Levodopa responsiveness was seen in 75% of patients including one with levodopa-induced dyskinesia. Of 139 patients from 49 studies, levodopa was tried in 123 patients. Improvement with levodopa was seen in 71 patients (57.72%). No improvement with levodopa was observed in 33 patients (26.82%) and details regarding therapeutic response were unavailable in 19 patients (15.44%). Dystonia is an important clinical manifestation of HT. Levodopa responsiveness seen in the majority of the patients is consistent with the hypothesis that nigrostriatal pathway damage is crucial for the pathophysiology of HT.

Therapies, Research Funding, and Racial Diversity in Essential Tremor: A Systematic Review of the Literature.

Essential tremor (ET) is one of the most common tremor disorders in the world. Despite this, only one medication, propranolol, is approved by the Food and Drug Administration to treat it. We analyzed controlled clinical trials in ET, spanning the last 50 years, to identify potential shortcomings in the therapeutic clinical pipeline. Outcomes reviewed included demographics (specifically gender and race), therapeutic modalities, funding information, location of research, and trends over time. Clinical trials published in English were identified in scientific databases (Pubmed, SCOPUS, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform from 1970 through December 2021. Included trials were prospective, either single- or double-blinded (including blinded video assessments for surgical trials), with change in limb, head, or voice tremor as the primary outcome measure. One hundred and eighty-six controlled clinical trials were accepted for extraction, including 4207 patients. Of the 145 trials that included gender, males comprised 59% of the patient population. Only 6.4% of studies provided racial demographics; in these studies, 70.5% of patients were Caucasian. The most common therapeutic modality over the past 50 years was "pharmaceutical" (56%), and the most common pharmaceutical studied was propranolol (32%). 41% of clinical trials reported no specific funding. Future efforts should focus on increasing funding for clinical trial research in ET worldwide, and trials should be designed to be more inclusive of disadvantaged minorities.

L-Dopa response, choreic dyskinesia, and dystonia in Perry syndrome

IntroductionA marked response to L-Dopa and L-Dopa-induced dyskinesia (LID) make the diagnosis of Parkinson's disease (PD) highly likely. This paper evaluates response to L-Dopa in Perry syndrome (PS), parkinsonism with distinct molecular and neuropathologic characteristics. MethodsSix patients with PS with a mean follow-up of 5 years (0.5–12) were assessed by movement disorder specialists and video recorded in states off and on. Additionally, DATSCAN-SPECT was performed in 3 subjects. ResultsFour patients displayed a marked and sustained response to L-Dopa and LID. Additionally, we observed a distinct pattern of off-state predominant craniocervical dystonia responsive to L-Dopa in 4 patients, truncal dystonia in one, and dystonic head tremor in another. DATSCAN-SPECT was abnormal in 3 patients. ConclusionsPatients with PS may present PD-like parkinsonism with a marked and sustained response to L-Dopa and LID. The characteristic pattern of craniocervical dystonia may be a helpful clue to the diagnosis of PS.