Effects of subthalamic nucleus lesions in a putative model of tardive dyskinesia in the rat

The effects of bilateral excitotoxic lesions of the subthalamic nucleus on vacuous chewing movements induced by chronic neuroleptic therapy were examined in the rat. Fluphenazine decanoate (25 mg/kg i.m. q 3 weeks × 24 weeks) induced vacuous chewing movements, as previously described. This response was suppressed to control levels in animals tested 1–3 weeks following bilateral infusion of quinolinic acid (100 nmol/1 μl per side) into the subthalamic nucleus. Subthalamic nucleus lesions resulted in increased locomotion and sniffing in neuroleptic-naive animals, but these responses were suppressed by concomitant neuroleptic treatment. As vacuous chewing movements induced by chronic neuroleptics are considered to be analogous to tardive dyskinesia in humans, our findings lend further support to the importance of the subthalamic nucleus in the regulation of orofacial movements and suggest that tardive dyskinesia may, in part, be related to altered activity in this structure. This, in turn, suggests that current models of basal ganglia function are inadequate to account for certain pathological states and require re-examination. © 1996 Wiley-Liss, Inc.     

Lacosamide for children with paroxysmal kinesigenic dyskinesia

ObjectivesThis study was performed to evaluate the efficacy and tolerability of lacosamide (LCM) for paroxysmal kinesigenic dyskinesia (PKD) in children.MethodsWe retrospectively reviewed the medical charts of pediatric PKD patients (aged <16 years) treated with LCM. Data regarding demographic characteristics, proline-rich transmembrane protein 2 (PRRT2) gene variant, clinical features of PKD, dose of LCM, efficacy, and adverse events were recorded.ResultsFour eligible patients (3 males, 1 female) were identified, with an age of onset ranging from 8.3 to 14.7 years. PRRT2 variant was evaluated in three children and a c.649dupC variant was identified in one child with a positive family history. Attacks were bilateral in three children and left-sided in one. Two children had a family history of PKD and one child had a family history of benign infantile epilepsy. Treatment with carbamazepine failed in two children due to drowsiness and auditory disturbance. The initial dose of LCM was 50 mg/day in three children and 100 mg/day in one. All patients were attack-free within a few days. The maintenance dose was mostly similar to the initial dose. No adverse events related to LCM were reported during follow-up.ConclusionsLCM is an effective and well-tolerated treatment for PKD in children, and low-dose treatment may be viable.     

脑出血病人上肢运动功能障碍相关弥散张量成像研究简

目的探讨利用弥散张量成像（diffusion tensor imaging,DTI）技术评估与高血压脑出血病人上肢运动功能障碍相关的皮质脊髓束（corticospinaltract,CST）受损情况。方法运用DTI技术三维重建21例高血压脑出血病人病变侧CST,分析CST受损情况与病侧Brunnstrom上肢评分以及美国国立卫生院神经功能缺损评分（national institutes of health stroke scale,NIHSS）之间的关系。结果DTI所显示的CST受损程度与Bmnnstrom上肢评分呈负相关（Rs=-0．83,P〈0．001）,与NIHSS评分呈正相关（Rs：0．79,P〈0．001）。结论DTI可直观显示与脑出血病人上肢功能障碍密切相关的CST受损情况,有助于病情的客观评估。     

Anticonvulsant-induced dyskinesia

Anticonvulsant-induced dyskinesia (AID) is an underdiagnosed side effect of many anticonvulsants that may take place during initial or chronic treatment at normal or toxic drug levels. The occurrence of AID subjects the patient to another medical condition and may prompt an extensive work-up. Similarities with other drug-induced dyskinesias and some animal studies suggest that dopaminergic dysfunction in the basal ganglia is pivotal in the occurrence of dyskinesia. Clinical presentation and outcomes are variable; however, in most cases, dyskinesias respond well to anticonvulsant withdrawal. Enhancing the awareness of AID is important in light of the recent development of many new anticonvulsants and their wider clinical use.     

Neuronal intranuclear inclusion disease: Two cases of dopa‐responsive juvenile parkinsonism with drug‐induced dyskinesia

There are very few conditions that present with dopa‐responsive juvenile parkinsonism. We present two such children with neuronal intranuclear inclusion disease (NIID) who had an initial good levodopa response that was soon complicated by disabling dopa‐induced dyskinesia. One child was diagnosed by rectal biopsy in life, and the other diagnosis was confirmed at postmortem. In this patient, dopamine transporter imaging showed severely decreased binding of the radiotracer in the striatum on both sides. Bilateral subthalamic deep brain stimulation in this patient produced initial improvement, but this was not sustained. Both patients died within 10 years of symptom onset. As well as levodopa responsiveness with rapid onset of dyskinesia, clues to the diagnosis of NIID in patients presenting with parkinsonism include the presence of gaze‐evoked nystagmus, early onset dysarthria and dysphagia and oculogyric crises. Differential diagnosis of clinical symptoms and neuropathological findings are discussed including the approach to rectal biopsy for early diagnosis. © 2010 Movement Disorder Society     

Dyskinetic and dystonic cerebral palsy and birth

Two hundred and nineteen cases of the dyskinetic and dystonic forms of cerebral palsy which were seen in the course of three decades at a single clinic have been analysed. Fifty-seven patients had kernicterus. In the remaining 162, 71% of whom were born at term, birthweight was below the expected mean in two-thirds. There was no relationship between birth weight, or abnormal birth, or asphyxia, and the ultimate clinical severity of the children. We conclude that abnormal birth and asphyxia are not direct causes of the cerebral damage, but are expressions of a pre-existing condition resulting in susceptibility to the stress of birth, whether it is normal or abnormal.