Stereotactic MRI in DYT1 dystonia: focal signal abnormalities in the basal ganglia do not contraindicate deep brain stimulation.

AIMS: To study stereotactic magnetic resonance imaging (MRI) features of the basal ganglia in DYT1 primary dystonia. METHODS: Twenty-five genetically confirmed DYT1 dystonia patients (age range, 8-66 years; mean age, 22 years) underwent brain MRI under general anesthesia at the time of globus pallidus internus (GPi) deep brain stimulation (DBS) surgery. MR images were retrospectively reviewed for signal intensity alterations. Clinical improvement of patients was assessed by comparing pre- and postoperative Burke-Fahn-Marsden Dystonia Rating Scale scores. RESULTS: Seventeen patients out of 25 (68%) exhibited T(1)-weighted hypointense/T(2)-weighted hyperintense signal abnormalities in the putamen and globus pallidus on MR images. Signals were isointense with cerebrospinal fluid in all sequences. The mean volume of focal signal abnormalities was 15 mm(3) (maximum, 154.5 mm(3)). The total volume of focal signal abnormalities in the basal ganglia was correlated with the duration of the disease (p = 0.01). Although clinical outcome did not differ as a function of the presence of focal signal abnormalities overall, patients with signals within the GPi tended to show lesser improvement (p = 0.04). CONCLUSIONS: T(1)-hypointense/T(2)-hyperintense signal abnormalities are common findings in the putamen and globus pallidus of DYT1 patients but do not contraindicate DBS. However, their presence within the GPi may reduce the efficacy of DBS treatment.

[Neurosurgical treatment in childhood dystonias and dyskinesias]. / Tratamientos neuroquirúrgicos en las distonías y discinesias de la infancia.

AIM: To present the post-surgery clinical results of deep brain stimulation of the internal globus pallidus (GPi) in a group of paediatric patients with primary and secondary dystonic-dyskinetic syndrome. PATIENTS AND METHODS: Between November 1996 and May 2006, 121 patients were submitted to interventions with bilateral deep brain stimulation of the GPi, 58 of whom were children (age range: 5-16 years); 35 were cases of primary dystonia, of which 17 were carriers of the DYT1 mutation and 10 were not. A further 8 cases were myoclonic dystonias, 3 of whom presented the DYT11 mutation. With regard to the secondary dystonias, 4 were carriers of PKAN (pantothenate kinase-associated neurodegeneration) syndrome and 9 were cases of post-anoxic encephalopathies. RESULTS: Percentage improvements were as follows: in the case of DYT1+ primary dystonias, 80% at one year maintained at 3 years; in cases of DYT1-, 70% at one year maintained at 3 years, and in the myoclonic dystonias, 50% at one year and 85% at 3 years. In the group of patients with secondary dystonias due to post-anoxic encephalopathies, we found an improvement of 30% at one year and 40% at 3 years; in the group with PKAN syndrome, the figures were 60% at one year and 50% at two years. CONCLUSIONS: Treatment involving bilateral deep brain stimulation of the GPi nuclei in childhood cases of generalised dystonias is highly effective, the best prognoses being those offered by the group with primary dystonias and especially those related to the DYT1 mutation. Treatment also proved to be effective in the case of secondary dystonias, although with lower degrees of improvement.

Tratamientos neuroquirúrgicos en las distonías y discinesias de la infancia / Neurosurgical treatment in childhood dystonias and dyskinesias

Objetivo. Presentar los resultados clínicos poscirugíade estimulación cerebral profunda del globo pálido interno (Gpi)en un grupo de enfermos pediátricos con síndrome distonodiscinéticoprimario y secundario. Pacientes y métodos. Desde noviembrede 1996 hasta mayo de 2006 se operaron con estimulación cerebralprofunda del Gpi, de forma bilateral, 121 enfermos, de los cuales58 eran niños (rango de edad: 5-16 años): 35 eran distonías primarias,de los que 17 eran portadores de la mutación DYT1, 10 no y 8eran distonías mioclónicas, tres de ellas con la mutación DYT11.En cuanto a las distonías secundarias, 4 eran portadores del síndromePKAN (pantothenate kinase-associated neurodegeneration) y9 eran encefalopatías postanóxicas. Resultados. La mejoría porcentualfue la siguiente: en el caso de las distonías primariasDYT1+, 80% al año mantenida a los 3 años; en los DYT1–, 70% alaño mantenida a los 3 años, y en las distonías mioclónicas, 50%al año y 85% a los 3 años. En el grupo de enfermos con distoníassecundarias por encefalopatías postanoxicas encontramos una mejoríadel 30% al año y 40% a los 3 años, y en el grupo con síndromePKAN, 60% al año y 50% a los dos años. Conclusiones. El tratamientopor estimulación cerebral profunda bilateral de los núcleosdel Gpi en los casos de distonías generalizadas de la infanciaes altamente eficaz, siendo el grupo de las distonías primarias y especialmentelas relacionadas con la mutación DYT1 las de mejorpronóstico. En el caso de las distonías secundarias, la eficaciatambién se ha probado, aunque con grados de mejoría inferiores

Aim. To present the post-surgery clinical results of deep brain stimulation of the internal globus pallidus (GPi) ina group of paediatric patients with primary and secondary dystonic-dyskinetic syndrome. Patients and methods. BetweenNovember 1996 and May 2006, 121 patients were submitted to interventions with bilateral deep brain stimulation of the GPi,58 of whom were children (age range: 5-16 years); 35 were cases of primary dystonia, of which 17 were carriers of the DYT1mutation and 10 were not. A further 8 cases were myoclonic dystonias, 3 of whom presented the DYT11 mutation. With regardto the secondary dystonias, 4 were carriers of PKAN (pantothenate kinase-associated neurodegeneration) syndrome and 9were cases of post-anoxic encephalopathies. Results. Percentage improvements were as follows: in the case of DYT1+primary dystonias, 80% at one year maintained at 3 years; in cases of DYT1–, 70% at one year maintained at 3 years, and inthe myoclonic dystonias, 50% at one year and 85% at 3 years. In the group of patients with secondary dystonias due to postanoxicencephalopathies, we found an improvement of 30% at one year and 40% at 3 years; in the group with PKAN syndrome,the figures were 60% at one year and 50% at two years. Conclusions. Treatment involving bilateral deep brain stimulation ofthe GPi nuclei in childhood cases of generalised dystonias is highly effective, the best prognoses being those offered by thegroup with primary dystonias and especially those related to the DYT1 mutation. Treatment also proved to be effective in thecase of secondary dystonias, although with lower degrees of improvement