Rechargeable Deep Brain Stimulators in the Management of Paediatric Dystonia:Well Tolerated with a Low Complication Rate

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; Deep brain stimulation (DBS) is a recognised method of treatment for primary and secondary dystonia. The size of non-rechargeable batteries has limited their use in small children. Our severe dystonia patients have required battery replacement every 20–24 months. &lt;b&gt;&lt;i&gt;Objectives:&lt;/i&gt;&lt;/b&gt; To evaluate reliability, care burden, patients’ satisfaction and complications related to the rechargeable neurostimulator Activa® RC (launched by Medtronic in Europe in autumn 2008). &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Complications were recorded prospectively, and a questionnaire on neurostimulator maintenance, care burden and parental satisfaction was applied to all patients with at least 3 months of follow-up. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; 30 Activa RCs were implanted between December 2008 and June 2010, 25 with a follow-up of 3–17 months (mean 10); the mean patient’s age at surgery was 11.1 years; 22/25 questionnaires were completed. All families achieved good standards of recharging. Caregivers were responsible for recharging in 82% of cases. With higher parameters of stimulation, recharging time was longer than initially recommended by the manufacturer. All but one family would recommend Activa RC to other patients. Transient recharging problems were the most common complication (36% of cases). Infection/skin erosion occurred in 8% of cases, self-resolving early seroma in 20%. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; Activa was found to offer reliable stimulation with a low rate of significant complications and a suitable treatment option for children with dystonia.</jats:p

Bilateral subthalamic nucleus deep brain stimulation for refractory total body dystonia secondary to metabolic autopallidotomy in a 4-year-old boy with infantile methylmalonic acidemia

The methylmalonic acidemias (MMAs) are a group of inborn errors of metabolism resulting in the accumulation of methylmalonic acid in body tissues and fluids. A recognized complication of MMA is bilateral liquefaction of the globus pallidi, resulting in a fulminant total body dystonia of childhood often refractory to medical treatment. This case of total body dystonia due to MMA in a 4-year-old boy had been medically refractory for 15 months. Complete metabolic destructive liquefaction of the pallidi, that is, autopallidotomy, necessitated an alternative, bilateral subthalamic nucleus (STN) target for deep brain stimulation (DBS) with a marked improvement in dystonia and reduction in pain. The case illustrates the efficacy of STN DBS in this condition and the technical challenges in targeting the STN in a small child.</jats:p

Shielded Battery Syndrome:A New Hardware Complication of Deep Brain Stimulation

&lt;i&gt;Background: &lt;/i&gt;Deep brain stimulation hardware is constantly advancing. The last few years have seen the introduction of rechargeable cell technology into the implanted pulse generator design, allowing for longer battery life and fewer replacement operations. The Medtronic® system requires an additional pocket adaptor when revising a non-rechargeable battery such as their Kinetra® to their rechargeable Activa® RC. This additional hardware item can, if it migrates superficially, become an impediment to the recharging of the battery and negate the intended technological advance. &lt;i&gt;Aim:&lt;/i&gt; To report the emergence of the ‘shielded battery syndrome’, which has not been previously described. &lt;i&gt;Methods:&lt;/i&gt; We reviewed our deep brain stimulation database to identify cases of recharging difficulties reported by patients with Activa RC implanted pulse generators. &lt;i&gt;Results:&lt;/i&gt; Two cases of shielded battery syndrome were identified. The first required surgery to reposition the adaptor to the deep aspect of the subcutaneous pocket. In the second case, it was possible to perform external manual manipulation to restore the adaptor to its original position deep to the battery. &lt;i&gt;Conclusions:&lt;/i&gt; We describe strategies to minimise the occurrence of the shielded battery syndrome and advise vigilance in all patients who experience difficulty with recharging after replacement surgery of this type for the implanted pulse generator.</jats:p

Beta-propeller protein-associated neurodegeneration:a new X-linked dominant disorder with brain iron accumulation

Neurodegenerative disorders with high iron in the basal ganglia encompass an expanding collection of single gene disorders collectively known as neurodegeneration with brain iron accumulation. These disorders can largely be distinguished from one another by their associated clinical and neuroimaging features. The aim of this study was to define the phenotype that is associated with mutations in WDR45, a new causative gene for neurodegeneration with brain iron accumulation located on the X chromosome. The study subjects consisted of WDR45 mutation-positive individuals identified after screening a large international cohort of patients with idiopathic neurodegeneration with brain iron accumulation. Their records were reviewed, including longitudinal clinical, laboratory and imaging data. Twenty-three mutation-positive subjects were identified (20 females). The natural history of their disease was remarkably uniform: global developmental delay in childhood and further regression in early adulthood with progressive dystonia, parkinsonism and dementia. Common early comorbidities included seizures, spasticity and disordered sleep. The symptoms of parkinsonism improved with l-DOPA; however, nearly all patients experienced early motor fluctuations that quickly progressed to disabling dyskinesias, warranting discontinuation of l-DOPA. Brain magnetic resonance imaging showed iron in the substantia nigra and globus pallidus, with a ‘halo’ of T(1) hyperintense signal in the substantia nigra. All patients harboured de novo mutations in WDR45, encoding a beta-propeller protein postulated to play a role in autophagy. Beta-propeller protein-associated neurodegeneration, the only X-linked disorder of neurodegeneration with brain iron accumulation, is associated with de novo mutations in WDR45 and is recognizable by a unique combination of clinical, natural history and neuroimaging features