Cranial Dystonia Research Articles

Isolated frontalis, corrugator and procerus dystonia: a blepharospasm variant

Blepharospasm (BSM) is a form of cranial dystonia caused by involuntary bilateral eye closure produced by contractions of orbicularis oculi muscles, often accompanied by dystonic movements of the eyebrows, paranasal, facial, masticatory, labial, lingual, oral, pharyngeal, laryngeal and cervical muscles1-3. In most instances, BSM is idiopathic. However, cases associated with lesions in rostral brainstem or other parts of basal ganglia (multiple sclerosis, stroke, thalamotomy and autoimmune disorders) have been described 1,3,4 […] Isolated frontalis, corrugator and procerus dystonia – a blepharospasm [...]

Current and future medical treatment in primary dystonia

Dystonia is a hyperkinetic movement disorder, characterized by involuntary and sustained contractions of opposing muscles causing twisting movements and abnormal postures. It is often a disabling disorder that has a significant impact on physical and psychosocial wellbeing. The medical therapeutic armamentarium used in practice is quite extensive, but for many of these interventions formal proof of efficacy is lacking. Exceptions are the use of botulinum toxin in patients with cervical dystonia, some forms of cranial dystonia (in particular, blepharospasm) and writer's cramp; deep brain stimulation of the pallidum in generalized and segmental dystonia; and high-dose trihexyphenidyl in young patients with segmental and generalized dystonia. In order to move this field forward, we not only need better trials that examine the effect of current treatment interventions, but also a further understanding of the pathophysiology of dystonia as a first step to design and test new therapies that are targeted at the underlying biologic and neurophysiologic mechanisms.

Pan-American Consortium of Multiple System Atrophy. Preliminary Report (P06.079)

Objective: To describe the clinical and epidemiological characteristics of a series of patients diagnosed with MSA from 5 different centers from North America and Latin America. Background Multiple system atrophy (MSA) is a rare, sporadic and rapidly progressive neurodegenerative disorder that presents with parkinsonism, cerebellar ataxia and autonomic failure. Clinical, demographic and epidemiological data from different centers have provided valuable information concerning the natural history of MSA and have contributed to improved diagnostic criteria. Design/Methods: We retrospectively analyzed the clinical data of 78 patients with probable MSA from 5 different movement disorders centers from Argentina, Chile, Mexico and the United States. Evaluations were performed according to the clinical and imagenologic criteria recently established. No patients with probable MSA were confirmed by autopsy. Results: Forty women and 38 men were included, with a mean age of 65,5 ±10 years. Family history was negative in 64 patients and unknown in 14. Seventy five percent corresponded to MSA-P variant. Dysautonomic symptoms were observed in 90,8 % of individuals, including mictional urgency 84,6%, orthostatism 65,3%, “cold hands” 41,9%, and severe hypophonia 86%. Dysphagia, falls and cranial cervical dystonia were present in the majority of cases. Response to levodopa was poor and transitory. MR imaging showed putaminal atrophy in 16 patients and hyperintense putaminal rims in 13 and the “hot cross bun” sign in 6. The mean estimate survival was 6 years (range 1-14). Chile and Mexico were countries with greater “mestizo” populations. Conclusions: The present series presents preliminary data about MSA in centers from North America and Latin America. In spite of the great ancestry variability observed in this population, no differences were observed regarding the other Western series. Disclosure: Dr. Gatto has nothing to disclose. Dr. Chana has nothing to disclose. Dr. Etcheverry has nothing to disclose. Dr. Gallin has nothing to disclose. Dr. Miranda has nothing to disclose. Dr. Parisi has nothing to disclose. Dr. Sanguinetti has nothing to disclose. Dr. Rodriguez Violante has nothing to disclose. Dr. Litvan has nothing to disclose.

Pre‐operative evaluations for DBS in dystonia

The preoperative evaluation in dystonia aims at characterizing the severity and topography of motor symptoms in patients, who have previously been selected for deep brain stimulation (DBS). The literature search was performed using PubMed, CINAHL, and the Cochrane Collaborative databases. Commonly used scales for clinical assessment are the Burke-Fahn-Marsden dystonia rating scale for generalized dystonia and the Toronto Western Spasmodic Torticollis Scale for cervical dystonia. Motor assessment is completed by quality of life and functional scales, such as the Short-Form Health Survey (SF-36) or the Parkinson's Disease Questionnaire 39. Validated rating scales for cranial or upper limb dystonia are lacking. In common clinical practice, these outcome measures can be administered in an open-label fashion because double blind assessment is only required for ascertaining new treatment indications or research purposes. The same measures are to be used postoperatively to revaluate outcome after DBS. Brain MRI is required to confirm diagnosis and assess structural abnormalities. Other imaging techniques, particularly functional imaging, are used for research purposes.

Treatment of Generalized Dystonia

The armamentarium for clinicians treating patients with generalized dystonia, previously restricted to only a few oral medications that often caused intolerable side effects, has been radically expanded in the past decade with the widespread application of deep brain stimulation (DBS). With DBS, patients who in the past would have been restricted to a life of severe motor disability from a young age can now lead lives with only minimal symptoms. Although DBS should therefore be considered as a treatment option for any patient with severe, medically refractory dystonia, important questions remain about patient selection, including what factors predict which patients will benefit from DBS, and when in the course of disease DBS should be performed. Reports show that patients with primary dystonia respond better than those with secondary dystonia, and limb and axial muscles may improve more than cranial dystonia. Some studies also suggest that shorter duration of disease may be associated with better outcomes. However, it is important to note that even among those thought to respond best to DBS, i.e. patients with primary generalized dystonia, there is a subset that will have significant and sustained clinical benefit with oral medications. It is therefore important that adequate trials of oral medications be attempted prior to referral for surgery. On the other hand, once it is clear that medical therapies are not providing significant benefit or are not well tolerated, children with disabling generalized primary dystonia should be referred quickly for DBS. The dramatic clinical improvement that can be seen with DBS can restore normal or near-normal functioning and avoid the physical and emotional costs of an extended period of decreased physical and social functioning. In general, a levodopa trial should always be considered as the first treatment at the time of presentation of any patient with childhood-onset limb dystonia, in order to exclude dopa-responsive dystonia. Once a diagnosis of primary generalized dystonia is established, we typically initiate treatment with trihexyphenidyl, titrating slowly up to a high dose. We then frequently add baclofen as a second agent. If clinical improvement at that point is inadequate and the dystonia is causing significant functional impairment, we then consider referral for DBS.

The Broadening Application of Chemodenervation in X-Linked Dystonia-Parkinsonism (Part II): An Open-Label Experience With Botulinum Toxin-A (Dysport®) Injections for Oromandibular, Lingual, and Truncal-Axial Dystonias

ABSTRACTWhile the majority of chemodenervation clinics worldwide typically use botulinum toxins for the treatment of common conditions such as blepharopsams, cervical dystonia, limb dystonia, and spasticity, the unusually high concentration of X-linked dystonia-parkinsonism (XDP) has allowed us to collect and describe our experience in the use of botulinum toxin type A (BoNT-A) on rarer dystonic patterns. BoNT-A (Dysport®) was injected in a total 109 dystonias of XDP. Our cohort included: 50 cases in the oromandibular area (jaw opening: 32 cases, jaw closing: 12 cases, and jaw deviation: 6 cases); 35 cases in the lingual area (tongue protrusion: 27 cases and tongue curling: 8 cases); and, 24 cases in the truncal-axial area (flexor: 12 cases, extensor: 7 cases, and lateral-extensor: 5 cases). Interestingly, pain, often a nonprominent symptom of dystonias, was frequently reported in 40/50 XDP cases with oromandibular dystonia and 18/24 XDP cases with truncal-axial dystonia. All BoNT-A procedures were performed under electromyography guidance. A “high potency, low dilution” BoNT-A protocol was applied for oromandibular, lingual, cranial, cervical, and distal limb dystonias; whereas for dystonias of the abdominal, paraspinal, and proximal limb muscles, a “low potency, high dilution” BoNT-A injection protocol was applied. Outcomes measures included: the global dystonia rating scale (DRS) and pain visual analog scale (VAS) reduction at week 4; duration of BoNT-A effects; and, side effect profile. The median DRS score after 4 weeks was 3 (“substantial improvement”) for oromandibular and lingual dystonias and 2 (“moderate improvement”) for truncal-axial dystonias. Pain reduction was significantly reduced (75%–80% in oromandibular; 30%–80% in truncal-axial dystonias). The median duration of BoNT-A effect was 16 weeks for oromandibular, 12 weeks for lingual, and 11 weeks for truncal-axial dystonias. Compared to a generally safe and well-tolerated BoNT-A injections for truncal-axial dystonias, the oromandibular-lingual dystonias had the following frequency of adverse events: oromandibular—19% in jaw opening and 17% in jaw closing dystonias; lingual—19% in tongue protrusion and 13% in tongue curling dystonias. The most frequent adverse events were mouth dryness and dysphagia. Thus, BoNT-A injection working protocols may be adopted in XDP dystonia that adheres to cost minimization (e.g., lower dose end per selected muscle), while achieving some benefit, and potentially reduce the adverse event profile.

Cervical dystonia: A new phenomenological classification for botulinum toxin therapy

ABSTRACT Background Cervical dystonia (CD) is the most frequent form of focal dystonia. Over the last years botulinum toxin has been the treatment of choice, but a significant proportion of patients do not respond adequately to the preparation. It is this problem that has led to this analysis of the clinical forms of CD using additional CT and MRI examinations. Patients and Methods 78 patients were investigated whose primary CD was confirmed by the first diagnostic procedures. The position of the neck and head in lateral tilt, rotation and flexion backwards or forwards was clinically evaluated. All patients underwent CT of the soft tissues of the neck using slices at levels C1 to C7 and the bone window from the base of the skull to C7. The cervical spine and the soft tissues of the neck were examined in T1 and T2-weighted magnetic resonance imaging using a slice thickness of 2 mm, as well as in T1-weighting tilted towards the deep muscles of the neck. For comparison, the MRI data were subsequently analysed of 50 patients who did not have CD. The greatest diameter was measured and the form described of all the muscles able to be captured in the neck region, including the small neck muscles, and the positions of the cervical vertebra relative to each other were noted. Only the results of the clinical and CT bone window examinations are analysed here. Results It was found that, concerning lateral flexion and rotation, in 20% of the patients the disorder affected muscles that act on the atlanto-occipital joints (producing laterocaput and/or torticaput), and in a further 20%, only affected muscles that act on the cervical spine (producing laterocollis and/or torticollis). 60% exhibited both types of disorders, although with different degrees of head (-caput) and neck (-collis) involvement. This produced a ratio consequently for these forms of the disorder of 1:1:3. The position of C1, C2 and C3 to each other and to the base of the skull was captured in the CT bone window in angle degrees, and permitted torticollis (all 4 levels show the same angle of rotation) to be differentiated from torticaput (the base of skull and C1 levels show the same angle of rotation but at C2 and C3 this angle is different). Obviously the obliquus capitis inferior muscle has a particular role in torticaput: in 73% of the patients with CD it was clearly different on each side. Conclusions 1. It is necessary to distinguish between neck and head types (-collis and -caput) to establish the treatment strategy with Btx, since different groups of muscles are affected. 2. Visual analysis of the clinical picture is usually sufficient for differentiating dystonia involving muscles that have their origin or insertion on the cervical spine from the disorder involving muscles that have their origin or insertion on the skull. Imaging (CT bone window) is only useful in addition to clinical evaluation for assessing rotation of the head. 3. Lateral shift always occurs when there is laterocollis on one side and laterocaput on the other. A sagittal shift forwards, as a combination of anterocollis and retrocaput, is usually caused by bilateral dystonia of the sternocleidomastoid muscles. 4. Anterocollis can be differentiated from anterocaput by clinical lateral observation of the angle between the cervical spine and the thoracic spine and/or between the cervical spine and the base of the skull. The same applies to differentiating retrocollis from retrocaput. 5. The term ‘cervical dystonia’ should be understood as a generic term that encompasses both CD in the narrower meaning (where the muscles acting on the cervical spine are dystonic) and cranial dystonia (where it is the muscles acting on the skull that are dystonic). 6. If the classification of CD proposed here is taken into account, injections of Btx into muscles that are not involved in the dystonia can be avoided.

EFNS guidelines on diagnosis and treatment of primary dystonias

to provide a revised version of earlier guidelines published in 2006. primary dystonias are chronic and often disabling conditions with a widespread spectrum mainly in young people. primary dystonias are classified as pure dystonia, dystonia plus or paroxysmal dystonia syndromes. Assessment should be performed using a validated rating scale for dystonia. Genetic testing may be performed after establishing the clinical diagnosis. DYT1 testing is recommended for patients with primary dystonia with limb onset before age 30, and in those with an affected relative with early-onset dystonia. DYT6 testing is recommended in early-onset or familial cases with cranio-cervical dystonia or after exclusion of DYT1. Individuals with early-onset myoclonus should be tested for mutations in the DYT11 gene. If direct sequencing of the DYT11 gene is negative, additional gene dosage is required to improve the proportion of mutations detected. A levodopa trial is warranted in every patient with early-onset primary dystonia without an alternative diagnosis. In patients with idiopathic dystonia, neurophysiological tests can help with describing the pathophysiological mechanisms underlying the disorder. botulinum toxin (BoNT) type A is the first-line treatment for primary cranial (excluding oromandibular) or cervical dystonia; it is also effective on writing dystonia. BoNT/B is not inferior to BoNT/A in cervical dystonia. Pallidal deep brain stimulation (DBS) is considered a good option, particularly for primary generalized or cervical dystonia, after medication or BoNT have failed. DBS is less effective in secondary dystonia. This treatment requires a specialized expertise and a multidisciplinary team.

Decreased striatal dopamine receptor binding in primary focal dystonia: A D2 or D3 defect?

Dystonia is an involuntary movement disorder characterized by repetitive patterned or sustained muscle contractions causing twisting or abnormal postures. Several lines of evidence suggest that abnormalities of dopaminergic pathways contribute to the pathophysiology of dystonia. In particular, dysfunction of D2-like receptors that mediate function of the indirect pathway in the basal ganglia may play a key role. We have demonstrated with positron emission tomography that patients with primary focal cranial or hand dystonia have reduced putamenal specific binding of [(18)F]spiperone, a nonselective D2-like radioligand with nearly equal affinity for serotonergic 5-HT(2A) sites. We then repeated the study with [(18)F]N-methyl-benperidol (NMB), a more selective D2-like receptor radioligand with minimal affinity for 5-HT(2A). Surprisingly, there was no decrease in NMB binding in the putamen of subjects with dystonia. Our findings excluded reductions of putamenal uptake greater than 20% with 95% confidence intervals. The analysis of the in vitro selectivity of NMB and spiperone demonstrated that NMB was highly selective for D2 receptors relative to D3 receptors (200-fold difference in affinity), whereas spiperone has similar affinity for all three of the D2-like receptor subtypes. These findings when coupled with other literature suggest that a defect in D3, rather than D2, receptor expression may be associated with primary focal dystonia.

Botulinum toxin for treatment of dystonia

Botulinum toxin (BT) is used in various medical specialties. However, dystonia is still one of the most important indications for BT therapy. BT drugs consist of botulinum neurotoxin, complexing proteins and excipients. Botox, Dysport and Xeomin are BT type A drugs and produce similar therapeutic and adverse effects (AE). Neurobloc/MyoBloc is based upon BT type B. Its use is limited by substantial systemic anticholinergic AE. The potency of BT drugs may be compared as follows: Botox:Xeomin:Dysport:Neuobloc/MyoBloc = 1:1:3:40. BT selectively blocks the cholinergic innervation of striate and smooth muscles and exocrine glands. It can produce obligate, local and systemic AE. However, its overall AE profile including long-term safety is excellent. BT can be blocked by antibodies. Risk factors include single doses, interinjection intervals and the immunological quality of the BT drug applied. Planning of BT therapy is based upon target muscle identification and estimation of their dystonic involvement. For planning of BT therapy and BT placement, electromyography and imaging techniques may be used additionally. So far, total Xeomin and Botox doses of up to 840 MU have been used without clinically detectable systemic AE. BT can be used to treat focal dystonias including cranial, pharyngolaryngeal, cervical and limb dystonias. In segmental and generalized dystonias, BT therapy has to be focussed on the most relevant target muscles. Combinations with all other treatment options including deep brain stimulation are possible. Recent safety data and availability of immunologically improved BT drugs are now allowing higher BT doses thus expanding the use of BT into more widespread dystonias.

Lingual protrusion dystonia: Frequency, etiology and botulinum toxin therapy

The purpose of this study was to examine lingual protrusion dystonia (LPD); its frequency, etiology and response to botulinum toxin therapy. Previous literature suggests that LPD is more frequently the result of heredodegenerative disease and that the use of botulinum toxin therapy in LPD is associated with significant adverse effects. This is a retrospective database and record review from a movement disorder clinic. Of 421 dystonia patients, we identified 17 with LPD (4%). Of these cases, the diagnoses were: primary cranial dystonia (5), primary generalized dystonia (2), tardive dystonia (7), heredodegenerative disease (1), multifactorial (1) and post-infectious (1). All primary cases had concomitant oromandibular dystonia. In some secondary cases the LPD was the only cranial feature. Nine received botulinum toxin injections and 55.6% sustained moderate or marked improvement. Of 89 total botulinum toxin sessions, 66.3% had an excellent response, and 92.1% had some response. 97.8% of the sessions resulted in no significant adverse effects. On one occasion one patient developed severe dysphagia requiring placement of a percutaneous gastrostomy (PEG) tube. We conclude that LPD is rare, most commonly the result of tardive and primary dystonia. Botulinum toxin therapy may be very effective but needs to be utilized with care because of the possibility for the development of dysphagia.

Lower limb involvement in adult‐onset primary dystonia: frequency and clinical features

Despite the growing number of reports describing adult-onset primary lower limb dystonia (LLD) this entity has never been systematically evaluated in the general population of patients with primary adult-onset dystonia. From outpatients with adult-onset primary dystonia attending nine Italian University centres for movement disorders we consecutively recruited 579 patients to undergo a standardized clinical evaluation. Of the 579 patients assessed, 11 (1.9%) (8 women, 3 men) had LLD, either alone (n = 4, 0.7%) or as part of a segmental/multifocal dystonia (n = 7, 1.2%). The age at onset of LLD (47.9 +/- 17 years) was significantly lower than the age at onset of cranial dystonias (57.9 +/- 10.7 years for blepharospasm, and 58.9 +/- 11.8 years for oromandibular dystonia) but similar to that of all the other adult-onset primary dystonias. The lower limb was either the site of dystonia onset (36.4%) or the site of dystonia spread (63.6%). In patients in whom LLD was a site of spread, dystonia seemed to spread following a somatotopic distribution. Only one patient reported a recent trauma involving the lower limb whereas 36.4% of the patients reported pain at the site of LLD. Only 64% of our patients needed treatment for LLD, and similarly to previously reported cases, the most frequently tried treatments was botulinum toxin and trihexyphenidyl. The lower limb is an uncommon but possible topographical site of dystonia in adulthood that should be kept in consideration during clinical evaluation.

Meige's syndrome: A cranial dystonia treated with bilateral pallidal deep brain stimulation

Background Meige's syndrome is a rare form of segmental dystonia characterized by blepharospasm and oromandibular dystonia. Medical treatment including botulinum toxin injections usually present disappointing results. The experience on Deep Brain Stimulation (DBS) in the treatment of Meige's syndrome and other segmental dystonias is still limited. At the moment, only a few cases of pallidal DBS have been reported to improve this rare form of dystonia. Case description We report on a case of a woman with a 7-year history of Meige's syndrome, which rendered her functionally blind. The treatment with botulinum toxin injections failed to improve her symptoms, whereas stereotactic bilateral DBS of the pallidum led to a dramatic clinical improvement. Clinical assessment using the Burke–Fahn–Mardsen Dystonia Rating Scale (BFMDRS) in a double-blind manner, showed an improvement of 70% in the Movement score and 93.33% in the Disability score (84% reduction of the total score) on the 3 and 6 month follow-up. Conclusions Stereotactic pallidal DBS might be considered as a potential treatment in the management of Meige's syndrome.

Brain‐derived neurotrophic factor and risk for primary adult‐onset cranial‐cervical dystonia

Adult-onset dystonia may be related, amongst other factors, to abnormal neuronal plasticity in cortical and subcortical structures. Brain-derived neurotrophic factor is a major modulator of synaptic efficiency and neuronal plasticity. Recent works documented that a single nucleotide polymorphism (SNP) of the BDNF gene, the Val66Met SNP, modulates short-term plastic changes within motor cortical circuits. In this study we aimed at exploring the effect of this SNP upon the risk of developing common forms of primary adult-onset dystonia. We explored the influence of the Val66Met SNP of the BDNF gene on the risk of cranial and cervical dystonia in a cohort of 156 Italian patients and 170 age- and gender-matched healthy control subjects drawn from the same population. The presence of the rare Met allele was not significantly associated with the diagnosis of dystonia (age- and gender-adjusted odds ratios of 1.22, P = 0.38). The study had a >90% power to detect a 50% change in the risk of developing cranial-cervical dystonia associated with the presence of the Met allele. Moreover, there was no relationship between Val66Met SNP and age at dystonia onset or type of dystonia. Our data do not support the common variant Val66Met of the BDNF gene as an etiologic factor shared by the various forms of primary adult-onset dystonia.

Somatosensory temporal discrimination in patients with primary focal dystonia

Purposes:To determine whether somatosensory temporal discrimination will reliably detect subclinical sensory impairment in patients with various forms of primary focal dystonia.Methods:The somatosensory temporal discrimination threshold (STDT) was tested in 82...

Oromandibular dystonia: A dental approach

Oromandibular dystonia consists of prolonged spasms of contraction of the muscles of the mouth and jaw. Primary idiopathic forms and secondary forms exist. Secondary dystonia develops due to environmental factors; some cases of cranial dystonia after dental procedure have been reported, but the causal relationship between these procedures and dystonia remains unclear. Traumatic situations in the mouth, such as poor aligned dentures or multiple teeth extractions may cause an impairment of proprioception of the oral cavity, leading to subsequent development of dystonia. The clinical characteristics of oromandibular dystonia are classified according to the affected muscles. The muscles involved may be the muscles of mastication, muscles of facial expression, or the muscles of the tongue. At present, there is no known cure for OMD. The mainstay of treatment for most focal dystonia is botulinum toxin injections. It is important for the dentist to be familiar with oromandibular dystonia, as it can develop after dental treatment and is often misdiagnosed as a dental problem.

Treatment of focal dystonias with botulinum neurotoxin

This is a review on the use of injections of botulinum toxin for the treatment of focal dystonias. Disorders covered include cranial dystonia, cervical dystonia, spasmodic dysphonia, and focal hand dystonia. Considered are clinical aspects, alternative treatment strategies and principles of use of botulinum toxin injections.

Clinical spectrum of Hallervorden-Spatz syndrome in India

Hallervorden-Spatz syndrome is a rare autosomal recessive disorder that involves progressive extrapyramidal manifestations. Classical and atypical clinical presentations are known. Clinical details of patients admitted to the neurology ward or attending the movement disorder clinic of the All India Institute of Medical Sciences between January 2001 and July 2007 were reviewed. Sixteen patients (9 males and 7 females) were included in the study (median age 14 years; range 6–25). The most common clinical presentation was limb or cranial onset progressive dystonia. The patients with early onset had more frequent truncal and axial dystonia, including retrocollis, oromandibular-facial dystonia and chorea, dysarthria, pyramidal signs, gait disturbance, cognitive impairment, delay in milestones, retinitis pigmentosa, optic atrophy, oculomotor abnormalities, positive family history and acanthocytosis. Although rare, cerebellar ataxia, behavioural abnormalities, parkinsonism and apraxia of eyelid opening were exclusively seen in late onset patients. The present study highlights the heterogeneity of this disease entity and also describes certain unusual clinical features.

A prospective blinded evaluation of deep brain stimulation for the treatment of secondary dystonia and primary torticollis syndromes

The aim of this study was to provide an objective assessment of deep brain stimulation (DBS) for groups of patients with mixed secondary dystonia and primary torticollis syndromes by a blinded evaluation of 13 consecutive patients who underwent ineffective medical treatment and botulinum toxin injections. Nine patients with secondary dystonia and 4 with cranial dystonia involving prominent spasmodic torticollis were selected for a DBS implant after they underwent unsuccessful medical treatment. Preoperative videos and neurological assessments were obtained and the DBS implant was inserted into the globus pallidus internus. Postoperatively, DBS parameters were adjusted to provide optimal benefit. Postoperative videotapes and quality of life scores were obtained. Blinded randomized evaluation of videotapes was performed by a neurologist specializing in movement disorders. Videos were scored using the Unified Dystonia Rating Scale, Toronto Western Spasmodic Torticollis Rating Scale, Burke-Fahn-Marsden Dystonia Rating Scale, or Abnormal Involuntary Movement Scale. Quality of life scoring was assessed using a standardized 7-point Global Rating Scale. All 13 patients completed preoperative videotaping, medical assessment, and surgery. Optimal DBS programming was completed in 6.5 visits over 5.9 months. Seven patients reported marked improvement, 3 reported moderate improvement, 2 reported slight improvement or no change, and 1 was lost to follow-up. Examiner scores on the Global Rating Scale reflected patient self-reported scores. Global subjective gains and notable objective improvement were observed in 11 of 13 patients. Although the benefits were variable and not fully predictable, they were of sufficient magnitude to justify offering the procedure when medications and botulinum toxin injections have failed.

Unravelling the tortuous tale of dystonia

Unravelling the tortuous tale of dystonia