Showing papers in "Movement Disorders in 1994"

Unified Parkinson's disease rating scale characteristics and structure

Abstract: Our purpose was to verify some basic aspects of validation of the Unified Parkinson's Disease Rating Scale (UPDRS). One hundred and sixty-seven Parkinson's disease (PD) patients were included. Group A (n = 40) was simultaneously assessed by five raters who applied the UPDRS and other PD rating scales (PDRS). A set of timed tests, the Mini-Mental State Examination (MMSE), and the Hamilton Scale for Depression (HSD) were administered by an independent examiner. Group B (n = 127) was individually assessed through the UPDRS and the other PDRSs by one neurologist in four different hospitals. The UPDRS was administered in 16.95 +/- 7.98 min. The internal consistency was high (Cronbach's alpha = 0.96). Nevertheless, the items related to depression, motivation/initiative, and tremor were scarcely consistent. The Interrater reliability was satisfactory (all the items had k > 0.40). There was a high correlation of the UPDRS with the Hoehn and Yahr staging (rs = 0.71; p < 0.001) and some timed tests (finger tapping; arising from chair), but also with the MMSE and HSD (rs = 0.53; rs = 0.64; p < 0.001). The convergent validity with the other PDRS (Intermediate Scale and Schwab and England Scale) was very high (rs = 0.76-0.96; p < 0.001). The factor analysis identified six factors that explained 59.6% of the variance. The dimension "tremor" showed a remarkable independence. The UPDRS is a multidimensional, reliable, and valid scale, with some inconveniences derived from its internal consistency, discriminant validity, and pragmatic application.

Increased levels of lipid hydroperoxides in the parkinsonian substantia nigra: An HPLC and ESR study

Abstract: Previous studies examining the involvement of oxidative stress in the substantia nigra in Parkinson's disease have measured terminal products of lipid peroxidation or the function of antioxidant defense systems. We report a more specific early marker of lipid peroxidation, lipid hydroperoxides, in a high-performance liquid chromatography (HPLC) and electron spin resonance (ESR) investigation. HPLC-chemiluminescent detection revealed two classes of lipid hydroperoxides in brain tissue extracts--free fatty acid hydroperoxides and cholesterol lipid hydroperoxides. Only cholesterol lipid hydroperoxides were consistently detected in all tissue extracts. Cholesterol lipid hydroperoxides had a 10-fold increase in the Parkinson's disease substantia nigra compared to control subjects. ESR detection of radical degradation products, including those of lipid hydroperoxides, in nigral homogenates incubated with the spin trap N-t-butyl-alpha-phenyl nitrone (PBN) showed a marked variation in ESR signal between tissues. Despite the increased levels of lipid hydroperoxides in parkinsonian substantia nigra, there was no overall difference in ESR signal intensity between nigral tissues from controls and from patients with Parkinson's disease. The increased levels of an early component of the peroxidation chain in substantia nigra in Parkinson's disease support the hypothesis of a continuous toxic process involving oxygen radical activity. However, using previously frozen tissue, ESR evidence for increased radical formation could not be demonstrated.

Movement disorders following lesions of the thalamus or subthalamic region.

Abstract: Reports of 62 cases with a movement disorder associated with a focal lesion in the thalamus and/or subthalamic region were analyzed. Thirty-three cases had a lesion confined to the thalamus. Sixteen cases had a thalamic lesion extending into the subthalamic region and/or midbrain. Thirteen cases had a lesion in the subthalamic region or a subthalamic lesion extending into the midbrain. Nineteen cases with dystonia, 18 with asterixis, 17 with ballism-chorea, three with paroxysmal dystonia, and five with clonic or myorhythmic movements have been described. No case with isolated tremor has been described. In 53 cases with unilateral thalamic or subthalamic lesions, all but one with bilateral blepharospasm (associated with right posterior thalamic, pontomesencephalic, and bilateral cerebellar lesions) had dyskinesias in the limbs contralateral to the lesion. The other nine cases had bilateral paramedian thalamic lesions; seven developed bilateral dyskinesias, and the remaining two had unilateral dyskinesias. Regarding the 19 patients with dystonia, the two with bilateral blepharospasm had thalamic and upper brainstem lesions, and one with hemidystonia and torticollis had a subthalamic lesion. The other 16 patients all had a unilateral thalamic lesion with contralateral dystonia (10 hemidystonia, five focal dystonia affecting a hand and/or and one segmental dystonia involving face, arm, and hand). The exact location of the thalamic lesion was mentioned in 10 cases; the posterior or posterolateral thalamus was involved in six and the paramedian thalamus in four. These areas are more posterior or medial to the ventrolateral and ventroanterior thalamic nuclei, which receive pallido-thalamic and nigro-thalamic afferents. Two cases developed dystonia immediately after thalamotomy, and one case developed it 4 days after head trauma. The others initially had a hemiplegia and developed dystonia 1-9 months after the acute insult. Fifteen of the 17 patients with chorea had a unilateral lesion in the subthalamic nucleus or subthalamic region (eight due to infarcts, one to hemorrhage, five to mass lesions, and one to multiple sclerosis). All had contralateral hemichorea or hemiballism. One other case had bilateral chorea of the hands and tongue due to paramedian thalamic infarction. Another case with generalized chorea and thalamic atrophy was complicated by stereotaxic surgery. Thirteen of the 18 cases with asterixis had lesions confined to the thalamus. Eight were associated with thalamotomy, and five others had a stroke (four infarction and one hemorrhage) affecting the contralateral thalamus.(ABSTRACT TRUNCATED AT 400 WORDS)

Interrater reliability of the unified Parkinson's disease rating scale motor examination

Abstract: Interrater reliability of the Unified Parkinson's Disease Rating Scale (UPDRS) motor examination was assessed by three neurologists experienced in the administration of this scale. Intraclass correlation coefficients indicated good-to-excellent agreement for speeded repeated movements, resting tremor, arising from a chair, and gait; moderate agreement for action tremor, rigidity, posture, postural stability, and bradykinesia; and poor agreement for speech disorder and facial immobility. Overall, these results indicate that satisfactory interrater reliability is attainable with the UPDRS motor examination.

Utility of an objective dyskinesia rating scale for Parkinson's disease: inter- and intrarater reliability assessment.

Abstract: Although dyskinesia is a frequent and important problem in Parkinson's disease (PD), a reliable assessment measure has not been thoroughly developed and tested. We modified the Obeso dyskinesia scale to create an objective rating scale for dyskinesia assessment during activities of daily living. Thirteen physicians and 15 study coordinators involved in a clinical trial independently reviewed videotape segments of PD patients performing three tasks: walking, putting on a coat, and lifting a cup to the lips for drinking. Raters evaluated the severity of worst dyskinesia seen, the types of all dyskinesias seen, and the type of dyskinesia most associated with motoric disability. For all assessments, the total group showed statistically significant inter- and intrarater reliability. Physicians had a higher consistency than did coordinators, but for most measures the difference was not statistically significant. Physicians and coordinators found the scale easy to use and especially practical for rating dyskinesia severity and for identifying the most disabling dyskinesia. Dyskinesias can be assessed in clinical trials and warrant regular documentation.

Histologic assessment of dose‐related diffusion and muscle fiber response after therapeutic botulinum a toxin injections

Abstract: Fiber diameter variability, acetylcholinesterase staining properties, and average fiber diameter were determined 5 weeks after varying doses of botulinum A toxin were administered into albino rabbit longissimus dorsi muscle. The average fiber diameter within the muscle appeared to be a function of the dose of botulinum toxin injected. Fiber diameter variability correlated with the dose of botulinum toxin administered. Both fiber diameter variability and acetylcholinesterase spread characteristics showed a distinct diffusion gradient over a defined field within a muscle. At lower doses (1 IU), collapse of the diffusion gradient occurred over a 15-30-mm segment of muscle. At higher doses (5-10 IU), diffusion of botulinum A toxin effect occurred throughout the entire muscle with no apparent end point. This study demonstrated that botulinum A toxin produces a gradient of denervation in a given muscle and that both the magnitude of denervation and the extent of the gradient are dose dependent. Furthermore, both muscle fiber diameter variability and acetylcholinesterase staining were useful as measures of chemodenervation.

Levodopa-induced dyskinesias in Parkinson's disease phenomenology and pathophysiology.

Abstract: The aim of this study was to provide further insight into the phenomenology and pathophysiology of monophasic and biphasic dyskinesias induced by levodopa in Parkinson's disease. For this purpose, the type, localization, severity, and timing of dyskinesias were evaluated in 15 parkinsonian patients in relation to motor disability after administration of levodopa using a video-electromyographic recording device. Foot-dystonia, myoclonus, and akathisia were observed in most patients. The dyskinesias started in the foot, usually on the side most affected by the disease, and spread in an "ascending wave" to the contralateral side, the trunk, and upper extremities. In a few patients, onset was axial, spreading almost instantaneously to all limbs. The dyskinesias were dystonic and ballistic at the start, and became increasingly choreic as they attained the upper limbs. Their intensity was maximal in the lower limbs, then progressively decreased, while increasing in upper limbs and head. The results indicate that there is no strict dichotomy between biphasic and monophasic dyskinesias. In other words, there is a "continuum" between the first dyskinesias and those observed during the period of maximal clinical improvement. These dyskinesias can also appear in reverse order, as if there were an "oscillator" determining a sequence of alternating patterns.

A multicenter double‐blind placebo‐controlled trial of pergolide as an adjunct to sinemet® in Parkinson's disease

Abstract: Three hundred and seventy-six subjects with advanced Parkinson's disease participated in a prospective, double-blind placebo-controlled study of the dopamine agonist pergolide mesylate as an adjunct to Sinemet. At 6 months, patients randomized to pergolide had a statistically significant improvement in total Parkinson's score, scores of activities of daily living, motor function, number of "off" hours, Hoehn and Yahr stage, and numerous parameters of parkinsonian function including bradykinesia, rigidity, gait, and dexterity. This benefit was obtained with the addition of a mean dose of 2.94 mg of pergolide, which permitted a 24.7% reduction in dose of levodopa. Adverse reactions were, for the most part, mild, reversible, and not of major clinical significance. No significant cardiac or electrocardiographic abnormalities were detected. This study demonstrates that pergolide mesylate, as an adjunct to levodopa, is an effective antiparkinsonian agent that provides clinical improvement while permitting a reduction in levodopa dose.

Parkinsonian syndromes associated with hydrocephalus: Case reports, a review of the literature, and pathophysiological hypotheses

Abstract: We present nine cases of obstructive hydrocephalus (OH) associated with marked parkinsonism. Four patients had noncommunicating OH (NCOH) [three nontumoral aqueductal stenosis (AS), one tumoral AS]. The presentation was that of acute or subacute parkinsonism, usually at the time of acute recurrent ventricular obstruction. Three had a marked response to levodopa and required short-term treatment after shunting. However, one has remained levodopa dependent after 2 1/2 years. Three of the five patients with communicating OH (COH) presented with shunt-responsive normal pressure hydrocephalus (NPH), only later to develop progressive parkinsonism. One of these was found to have progressive supranuclear palsy (PSP) at autopsy and PSP was clinically suspected in one other patient. A third had an atypical course suggestive of PSP; however, autopsy demonstrated the combination of Lewy body parkinsonism and the sequelae of hydrocephalus. The remaining two COH patients presented with levodopa-responsive parkinsonism. Subsequent clinical features and imaging studies suggested the presence of NPH. The pathophysiology of hydrocephalic parkinsonism probably involves variable sites of dysfunction in the nigrostriatal pathway and/or the cortico-striato-pallido-thalamo-cortical circuit. At certain locations these pathways lie in close proximity to the ventricular system and may be subjected to mass effects and ischemic changes secondary to ventriculomegaly. The additional importance of possible associations between subcortical cerebral ischemia, NPH, and "degenerative" disorders such as PSP and Parkinson's disease is discussed.

The syndrome of painful legs and moving toes.

Abstract: The clinical presentation, symptoms, and signs in 20 new patients with the painful legs and moving toes syndrome are presented. Painful legs and moving toes may develop in the setting of spinal cord and cauda equina trauma, lumbar root lesions, injuries to bony or soft tissues of the feet, and peripheral neuropathy. In 4 of the 20 cases in the present study, no definite cause was found. Pain preceded the onset of toe movements in 18 cases, but in 2 the reverse sequence occurred. The pain had many of the characteristics of causalgia, but none of the patients exhibited the full picture of reflex sympathetic dystrophy, and peripheral trauma was the trigger in only 5 cases. Several patients reported that the occurrence of toe movements was closely related to the pain, although abolition of pain with lumbar sympathetic blocks was not necessarily associated with disappearance of the movements. Several features suggest a central origin for the movements. Symptoms may begin on one side and become bilateral; movements may be momentarily suppressed by voluntary action or exacerbated by changing posture; and electromyography reveals complex patterns of rhythmic activity with normal recruitment of motor units involving several myotomes. Three other patients with similar moving toes but no pain are also described. The occurrence of similar movements in the absence of pain raises the possibility that these cases represent examples at one end of a spectrum of disorders, with pain alone (causalgia) at the other end and the syndrome of painful legs and moving toes in between.(ABSTRACT TRUNCATED AT 250 WORDS)

"Apraxia of lid opening," a focal eyelid dystonia: clinical study of 32 patients.

Abstract: We have seen 32 patients with "apraxia of lid opening" (ALO) in the following clinical settings: as an isolated condition (3 patients), idiopathic blepharospasm (BSP, 20 patients, including 4 familial cases), progressive supranuclear palsy (PSP, 7 patients), and dystonic parkinsonian syndrome (2 patients). Twenty-nine patients treated with botulinum toxin into the orbicularis oculi muscle were rated before and after treatment and 83% of the patients improved on a clinical scale. Best results were obtained with injections directed toward the junction of the preseptal and pretarsal parts of the palpebral orbicularis oculi. Several patients also improved on anticholinergic drugs. Besides medical treatment, lid crutches, in conjunction with botulinum toxin injections, were useful in some patients. ALO is not a true apraxia; it constitutes an eyelid dystonia as shown by its clinical and electrophysiological features as well as pharmacological reactions and is encountered in a clinical spectrum ranging from an isolated form to predominant BSP. It was an important cause of treatment failures in botulinum toxin-treated BSP but by modifying our injection strategy and by adding anticholinergic drugs and also lid crutches, we obtained a good functional benefit.

A case-control study of Parkinson's disease in a horticultural region of British Columbia.

Abstract: We compared personal histories of 127 cases and 245 controls to identify possible environmental risk factors for idiopathic parkinsonism (IP) Of our controls, 121 had cardiac disease (CD) and 124 were randomly selected from electoral lists (voters) Using logistic regression and adjusting for sex and age, we ran separate analyses: IP versus CD and IP versus voters A full occupational history was collected, as was known contact with all pesticides associated with the tree fruit sector of the agricultural industry We found a significant association between IP and having had an occupation in which exposure through handling or directly contacting pesticides was probable, but no specific chemicals were associated with IP We conclude that although occupations involving the use of agricultural chemicals may predispose to the development of IP, it seems likely that the pathogenesis is multifactorial rather than related to a specific agent

Rating impairment and disability in Parkinson's disease: evaluation of the Unified Parkinson's Disease Rating Scale.

Abstract: Although the Unified Parkinson's Disease Rating Scale (UPDRS) is widely used to monitor disease progression and drug efficacy, no attempts have been made to evaluate its scientific and clinical quality. Poor clinical sensibility of items in the activities of daily living (ADL) section and redundancy of items in the motor examination (ME) section prompted us to determine if the number of items in these sections could be reduced to a smaller, equally sensitive set that would describe the data as relibly as did the original set of items. Therefore, we assessed 111 patients with idiopathic Parkinson's disease on the UPDRS and Hoehn and Yahr staging scales. Our results show that the ADL (13 items) and ME (14 items) sections can be reduced to 8 items each without loss of reliability or validity. Our report is preliminary and needs validation.

Visual control of arm movement in Parkinson's disease

Abstract: Patients with Parkinson's disease (PD) are more dependent on visual information during movements than normals. To investigate the mechanisms underlying deterioration of movement under nonvisual conditions, we studied two-dimensional pointing movements to randomly occurring targets. The experimental design allowed us to systematically manipulate visual feedback during the movement by removing vision of the target, of the moving hand, or of both. Execution of pointing movements in PD deviated most severely from that of normals when PD patients moved without vision of their own moving hand. Under this condition, undershooting of the target appeared, and movements were particularly slow. In contrast, with complete vision or when only vision of the target was occluded, pointing movements of PD patients were accurate and faster. PD patients had no difficulties selecting the correct movement direction. Reaction times were longer in PD patients irrespective of the availability of visual feedback. Our findings suggest that the ability of PD patients to use nonvisual feedback during execution of arm movements is impaired.

Botulinum toxin in the treatment of dystonic tics.

Abstract: Botulinum toxin (BTX) injections provide effective treatment for a variety of disorders manifested by inappropriate muscle contractions, but its efficacy in the treatment of tics has not been previously studied. Ten male patients 13-53 years of age who were diagnosed with Tourette's syndrome manifested by disabling focal tics were included in this pilot study. Five patients had frequent blinking and blepharospasm, rendering them "blind," and five patients had severe and painful dystonic tics involving their neck muscles. All 10 patients experienced moderate to marked improvement in the intensity and frequency of tics after BTX injections into the involved muscles. Patients in whom premonitory urges preceded their tics noted marked lessening of these sensory symptoms. The benefit lasted 2-20 weeks after injections. There were no serious complications, except for transient ptosis in two and neck pain, stiffness, or weakness in three patients. BTX injections appear to be safe and effective treatment for patients with focal dystonic tics. The treatment ameliorates not only involuntary movements but also the premonitory sensory component associated with some tics.

Neurological sequelae following carbon monoxide poisoning clinical course and outcome according to the clinical types and brain computed tomography scan findings.

Abstract: The prognosis for patients who survive carbon monoxide (CO) poisoning is uncertain, particularly in those who develop persistent neurological complications after recovery from the initial coma. Thirty-one patients with the sequelae of CO poisoning, followed for a year, are described. Eight had a progressive course, and 23 had a delayed relapse after an initial recovery period of approximately 20 days (range, 1-36 days). Those with a progressive course developed a persistent akinetic-mute state, and four of the eight died. Those with the delayed relapsing course either developed a parkinsonian state with behavioral and cognitive impairment but could walk (nine cases), or progressed further to an akinetic-mute state, and were bed-bound (14 cases); the deterioration to either condition occurred rapidly over a few days to a week. Fourteen of the patients with the delayed relapses (61%) subsequently improved, but three (13%) died. Those with a progressive course without initial recovery were younger (mean age, 37.0 years) than those with a delayed relapsing course (55.2 years; p < 0.01). The mean duration of their initial coma (9.8 days) was longer than that in delayed relapsing cases (2.0 days; p < 0.01). The mean initial CO hemoglobin level was not different in the two groups. Brain computed tomography (CT) scans were obtained at the onset of sequelae in both groups. Ten patients had a normal CT scan, 13 had white matter low-density lesions, and four had globus pallidus low-density lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Propriospinal myoclonus: Evidence for spinal “pattern” generators in humans

Abstract: The clinical and electrophysiological characteristics of eight patients with propriospinal myoclonus are described. Myoclonus developed within days or weeks of cervical trauma in half the patients. Seven cases had axial flexion jerks, and one axial extension jerks. Myoclonic EMG activity consisted of repetitive bursts with a frequency of 1-7 Hz. The jerks in three of the cases were comprised of alternating and rhythmic bursts of EMG activity in rectus abdominis and the paraspinal muscles. From these new observations, it is proposed that cervical trauma can lead to the partial release of a spinal pattern generator. The latter is capable of recruiting muscles through long propriospinal pathways into complex rhythmic activity.

Treatment of severe axial tardive dystonia with clozapine: Case report and hypothesis

Abstract: We report a patient with severe axial tardive dystonia who has had dramatic improvement for 4 years after treatment with the atypical antipsychotic drug clozapine (625 mg/day). Clozapine differs from conventional neuroleptics in that it has higher affinity for D1 and lower affinity for D2 dopamine receptors than do conventional antipsychotics, which are relatively selective D2 antagonists. We propose that repetitive stimulation of the D1 receptor by endogenous dopamine, resulting in sensitization of the D1-mediated striatal output in the presence of D2 receptor blockade, is a fundamental mechanism mediating tardive dyskinesia, including the dystonic type. According to this hypothesis, it is primarily the D1 antagonist action of clozapine that accounts for its inability to cause tardive dyskinesia as well as its therapeutic effect in tardive dystonia. Regardless of its mechanism of action, the sustained improvement observed in this case suggests that clozapine should be tried in cases of severe refractory tardive dystonia.

Botulinum toxin a injections for the treatment of hand tremors

Abstract: We conducted an open-label study to determine the utility of treating severe hand tremors with intramuscular injections of botulinum toxin (BTX) in forearm and arm muscles in 26 patients, 12 with Parkinson's disease (PD) and 14 with essential tremor (ET). The effect after 6 weeks for each patient was evaluated using two clinical rating scales, subjective evaluations of functional improvement and global disability, measures of weakness, and computer-assisted quantitative assessments of tremor. Although none of the clinical scores averaged > 3/4 point change, statistical significance was found on comparison of pre- and postinjection scores in the Webster Tremor and Global Disability Scales in the ET patients. Similarly, although average tremor amplitudes decreased by no more than 25% by quantitative analysis, amplitude decrease significantly correlated with patient subjective assessment in ET. In only two of 12 PD (17%) and three of 14 ET patients (21%) were major quantitative changes in tremor amplitude (> 50% reduction) found after BTX injections. Nevertheless, 10 patients (38%; five PD and five ET) reported moderate to marked subjective improvement in functional benefit after BTX. These findings suggest that although there were no major changes in clinical ratings or objective measurements, BTX injections may subjectively improve tremor in some patients, particularly those with ET.

Dystonia and dyskinesia in glutaric aciduria type I: clinical heterogeneity and therapeutic considerations.

Abstract: Glutaric aciduria type I (GA-I) is an inborn error in the degradation of lysine, hydroxylysine, and tryptophan due to a deficiency of glutaryl-CoA dehydrogenase. Glutaric, 3-OH-glutaric, and glutaconic acids are excreted in the urine, particularly during intercurrent illness. The enzyme may be assayed in leukocytes, cultured fibroblasts and chorionic villi. Twelve new cases, 9 months-16 years of age, are reported, comprising all known cases of GA-I in Sweden and Norway. Ten had a severe dystonic-dyskinetic disorder, one had a mild hyperkinetic disorder, and one was asymptomatic. Two children died in a state of hyperthermia. Carnitine deficiency and malnutrition developed in patients with severe dystonia and dysphagia, which necessitated substitution and gastrostomy. A slowly progressive dyskinetic disorder developed in spite of adequate early dietary treatment in one subject. Macrocephaly was found in three. Computed tomography and magnetic resonance investigations in 10 showed deep bitemporal spaces in 7. Neuropsychological testing of 8 of 12 subjects demonstrated receptive language function to be superior to expressive language and motor function. Cognitive functions were obviously less affected than motor functions. A review of 57 pooled cases showed that a severe dystonic syndrome developed in 77%, a mild extrapyramidal syndrome in 10%, and 12% were asymptomatic. This disorder may pass undetected in the cerebral palsy and mentally retarded child and adult populations. Repeated urine examinations of organic acids in the urine and enzyme assay may be necessary to confirm GA-I.

"Minimal change" multiple system atrophy.

Abstract: We describe the pathological findings in two patients who developed atypical parkinsonism and autonomic failure, leading to a diagnosis of multiple system atrophy (MSA). Postmortem examination of the brain showed cell loss restricted to substantia nigra and locus coeruleus. However, glial cytoplasmic inclusions (GCIs) were present in both cases. We propose that GCIs are highly suggestive of a pathological diagnosis of MSA in the absence of detectable cell loss outside pigmented brain stem nuclei and that brains from cases of atypical parkinsonism should routinely be examined for their presence.

Factors influencing the amplitude and frequency of essential tremor

Abstract: Quantitative electromyography (EMG) and triaxial accelerometry were used to measure hand tremor, finger tremor, and forearm motor unit activity in 36 men and 23 women with essential tremor. Hand tremor was studied with and without 300-g mass loading. Tremor and EMG were recorded twice, with a 3-min rest interval, to assess the spontaneous intertrial variability in tremor amplitude, frequency, and motor unit entrainment. In general, the minimum detectable differences in tremor amplitude, frequency, and motor unit entrainment were roughly 30%, 5%, and 10% of the initial sample means, respectively, assuming a sample size of 30 patients, a statistical power of 0.9, and a significance level of 0.05. Linear regression analyses were performed to test the hypotheses that (a) there is an age-associated decrease in tremor frequency that is independent of symptom duration and (b) tremor frequency and motor unit entrainment make independent contributions to tremor amplitude. Our data supported both hypotheses.

Naltrexone, an opiate antagonist, fails to modify motor symptoms in patients with Parkinson's disease

Abstract: One month of adjunct treatment with naltrexone (100 mg/day) was compared with placebo in a double-blind, randomized, cross-over design in two groups of patients with Parkinson's disease. The first group was composed of 10 patients with a moderate motor impairment insufficiently controlled by monotherapy with bromocriptine. The second group was composed of eight patients with L-dopa-induced peak-dose dyskinesia. Naltrexone as compared with placebo did not demonstrate any significant change in motor function in either group. These negative clinical results do not support a significant role of endogenous opioid systems in the pathophysiology of motor impairment in Parkinson's disease.

The neuropathological features of neuroacanthocytosis

Abstract: In this article we describe the neuropathological changes in three patients with neuroacanthocytosis and review the neuropathology of the other eight cases reported in the literature. Macroscopically the brains showed enlargement of the lateral ventricles, especially the frontal horns. The most severely and consistently affected brain areas were the caudate nucleus and putamen, which were atrophic and showed by light microscopy marked neuronal loss and gliosis. Small and medium-sized striatal neurons were particularly depleted. The globus pallidus was almost as severely involved as the striatum. In some cases the thalamus, substantia nigra, and anterior horns of the spinal cord showed pathology, mainly neuronal loss and mild gliosis. Brain areas with no pathology included the subthalamic nucleus, cerebral cortex, cerebellum, pons, and medulla. The preservation of these areas may help in the neuropathological distinction of neuroacanthocytosis from Huntington's disease.

Suppression of dyskinesias in advanced Parkinson's disease: moderate daily clozapine doses provide long-term dyskinesia reduction.

Abstract: Dyskinesias commonly appear during L-dihydroxyphenylalanine (L-DOPA) therapy of advanced Parkinson's disease (PD) and can occur in both dose-related and dose-independent patterns. Clozapine exerts a dose-related suppression of L-DOPA-induced dyskinesias by shifting the i.v. L-DOPA dose-response curve for production of dyskinesias without altering relief of parkinsonism. We report our outpatient experience with 13 patients on daily clozapine therapy (maximum dose 400 mg/day), followed for 3-21 months (median 10). Beneficial effects of clozapine, determined from twice-weekly diaries, included increased "on time" and decreased "off time" and time "on with dyskinesia." Improvements were statistically apparent by 75 mg/day and remained so through 200 mg/day. Sedation was a common problem, reflected by increased time "asleep" which was significant by 50 mg/day. Sedation was dose limiting in most patients. Orthostatic hypotension and sialorrhea were variably present. No patients had seizures, bone marrow toxicity, or detectable loss of efficacy of clozapine with chronic use. We conclude that clozapine is an effective agent for suppression of dyskinesias in PD with an effective daily dose for most patients of 100-200 mg/day.

Characteristics of handwriting of patients with Huntington's disease.

Abstract: Patients with Huntington's disease exhibit poorer-quality handwriting, sometimes clinically exhibiting macrographia, an increase in the size of handwriting. To characterize deficits in handwriting of patients with Huntington's disease, we compared the writing of 12 young, 12 age-matched controls, and 12 patients with Huntington's disease. Subjects were asked to write the letter "l" four times, at a constant length, on a graphics tablet that sampled pen position at 200 Hz. Huntington's disease causes chorea (involuntary movement), akinesia (difficulty in initiating voluntary movement), and bradykinesia (slowness and difficulty in maintaining voluntary movement). To distinguish changes in handwriting quality due to involuntary movement from impairments of voluntary movement, handwriting samples with obvious choreic movements were analyzed separately from other handwriting samples. Several measures of quality of handwriting were considered, based on: the regularity and consistency of handwriting, the efficiency of movement trajectories, and the proportions of movement occurring at specific frequencies. Results suggested that Huntington's disease increases variability of movement parameters, and causes problems in producing smooth movements. Choreic movement was best characterized by the number of zero crossings in the velocity function relative to the prescribed number of writing strokes. We hypothesize that macrographia in Huntington's disease occurs when chorea predominates over bradykinesia. Comparisons were made between the handwriting of patients with Huntington's and Parkinson's diseases.

Pergolide compared with bromocriptine in Parkinson's disease: A multicenter, crossover, controlled study

Abstract: We compared the efficacy and safety of pergolide and bromocriptine in 57 patients with Parkinson's disease (PD) with a declining response to levodopa therapy in a single-blind, crossover study. Patients were placed randomly on the sequence bromocriptine-pergolide (12 + 12 weeks) or vice versa. Regular evaluations using the New York University Parkinson's Disease Scale were performed by a clinician blinded to treatment assignment. Patients' and clinicians' impressions also were recorded. The average daily dose of pergolide was 2.3 +/0- 0.8 mg, and that of bromocriptine was 24.2 +/- 8.4 mg. Significantly greater efficacy was demonstrated by both drugs as adjunctive therapy to levodopa compared with previous treatment of levodopa alone (pergolide, p = 0.0001; bromocriptine, p = 0.0005; Wilcoxon t test). Pergolide was more effective than bromocriptine in daily living scores (p = 0.020) and motor scores (p = 0.038). No difference in dyskinesias, dystonias, and psychosis was observed. Adverse events were more frequent in bromocriptine-treated patients. Most patients and physicians preferred pergolide to bromocriptine. Pergolide as adjunctive therapy to levodopa was more effective than bromocriptine in this short-term trial.

Hereditary variations in monoamine oxidase as a risk factor for Parkinson's disease

Abstract: Parkinson's disease (PD) is a common neurodegenerative disorder caused by loss of dopaminergic neurons in the brainstem. Recent studies suggest that several genes may have a role in determining individual susceptibility to this disease, and the degradative enzyme monoamine oxidase (MAO) has been implicated in the disease process. Wide differences in activity levels for both forms of this enzyme (MAO-A and MAO-B) exist in the human population, and levels of both are genetically determined. Here we have compared the frequency of haplotypes at the MAOA and MAOB loci on the X chromosome in 91 male patients with PD and 129 male controls. Alleles were marked using two restriction fragment length polymorphisms (RFLPs), a (GT)n repeat in the MAOA locus, and a (GT)n repeat in the MAOB locus. One particular haplotype marked by the RFLP's at MAOA was three times more frequent in patients with PD as compared with controls, and the overall distribution of these alleles was significantly different (p = 0.03) between these two groups. Another MAOA haplotype was about threefold more common in controls than in patients with PD (p = 0.005). No associations were observed between individual MAOB alleles and the disease state, but the frequency distribution for all alleles was significantly different in the two populations (p = 0.046). These findings support the idea that the MAO genes may be among the hereditary factors that influence susceptibility of individuals to PD.

Symptomatic and essential palatal tremor. 2. Differences of palatal movements.

Abstract: Palatal tremor, a rhythmic movement disorder of the soft palate, may be described as two separate entities: symptomatic palatal tremor (SPT) and essential palatal tremor (EPT). The symptomatic form is associated with brain stem or cerebellar disease, whereas the essential form has no known etiology. A cardinal symptom of EPT is the presence of ear clicks, which do not occur in SPT. Visual observation of the movements in the two disorders suggests that the difference in symptoms is due to the activation of different palatal muscles, the levator veli palatini in SPT and the tensor veli palatini in EPT. Electromyographic recording from the levator veli palatini muscle showed abnormal bursting activity time locked to the palatal movements in patients with SPT, but not in those with EPT. Because the two palatal muscles are innervated by different cranial nerves, SPT and EPT are likely to have separate origins.

Akathisia in Parkinson's disease

Abstract: This study evaluated the prevalence and clinical characteristics of akathisia in a tertiary care Parkinson's disease (PD) practice, and assessed the agreement between investigators for the diagnosis of akathisia in PD, and the sensitivity and specificity of a brief patient questionnaire. Fifty-six consecutive PD patients completed an akathisia questionnaire and then were clinically evaluated for akathisia by two examiners blinded to the patient questionnaire. Overall, 45% of PD patients had akathisia as determined by clinical evaluation. Interrater reliability for the diagnosis of akathisia was high (K = 0.89). Patient self-report of restlessness agreed with examiner diagnosis in 89% of the patients. The presence of akathisia was associated with the severity and age of onset of PD. Symptoms most frequently affected the legs, and associated movements were suppressible for brief periods.