Microendoscopic transventricular deep brain stimulation of the anterior nucleus of the thalamus as a safe treatment in intractable epilepsy: A feasibility study.

INTRODUCTION: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) is proposed in patients with severe intractable epilepsy. When used, the transventricular approach increases the risk of bleeding due the anatomy around the entry point in the thalamus. To avoid such a complication, we used a transventricular microendoscopic technique. METHODS: We performed a retrospective study of nine adult patients who were surgically treated for refractory epilepsy between 2010 and 2019 by DBS of the anterior thalamic nucleus. RESULTS: Endoscopy provides a direct visual control of the entry point of the lead in the thalamus through the ventricle by avoiding ependymal vessels. No hemorrhage was recorded and accuracy was systematically checked by intraoperative stereotactic MRI. We reported a responder rate improvement in 88.9% of patients at 1 year and in 87.5% at 2 years. We showed a significant decrease in global seizure count per month one year after DBS (68.1%; P=0.013) leading to an overall improvement in quality of life. No major adverse effect was recorded during the follow-up. ANT DBS showed a prominent significant effect with a decrease of the number of generalized seizures. CONCLUSION: We aimed at a better ANT/lead collimation using a vertical transventricular approach under microendoscopic monitoring. This technique permitted to demonstrate the safety and the accuracy of the procedure.

Dentate nucleus as target for deep brain stimulation in dystono-dyskinetic syndromes.

PURPOSE: To discuss the potential of deep brain stimulation (DBS) of the dentate nucleus as a treatment for dystono-dyskinetic syndromes. METHODS: An extensive literature review covered the anatomy and physiology of the dentate nucleus and the experimental evidence for its involvement in the pathophysiology of dystonia and dyskinesia. RESULTS: Evidence from animal models and from functional imaging in humans is strongly in favor of involvement of the dentate nucleus in dystono-dyskinetic syndromes. Results from previous surgical series of dentate nucleus stimulation were promising but precise description of movement disorders being treated were lacking and outcome measures were generally not well defined. CONCLUSIONS: In the light of new evidence regarding the involvement of the dentate nucleus in dystono-dyskinetic syndromes, we present a review of the current literature and discuss why the question of dentate nucleus stimulation deserves to be revisited.

Long-term follow-up of pallidal Deep Brain Stimulation in teenagers with refractory Tourette syndrome and comorbid psychiatric disorders: About three cases.

OBJECTIVES: Tourette syndrome (TS) is a complex neuropsychiatric disorder associated with comorbid psychiatric disorders. Peak of tic severity typically occurs in early adolescence and impacts quality of life. Since 1999, promising therapeutic effects of Deep Brain Stimulation (DBS) have been reported in tic reduction for adults with refractory TS. The aim of the study was to assess the long-term risk-benefit ratio of pallidal DBS for young patients with refractory TS and severe comorbid psychiatric disorders. METHODS: We retrospectively assessed the long-term clinical outcomes of three adolescents who underwent pallidal DBS for the treatment of refractory TS. RESULTS: The mean duration of follow-up was 52 months in our case series. We observed that motor tics decreased with posteroventral GPi DBS in all patients, without reaching a continuous significance over the long-term follow-up. Self-reported social inclusion was globally improved, despite lack of efficacy of DBS on comorbid conditions. CONCLUSIONS: These findings suggest a long-term therapeutic benefit of early DBS intervention for highly socially impaired young patients suffering from intractable TS with severe comorbid psychiatric conditions. Further studies are needed to determine the most effective targets of DBS on both tics and comorbid psychiatric profile of TS.

Psychiatric comorbidity in temporal DNET and improvement after surgery.

BACKGROUND: "Alien tissue" may be responsible for a higher frequency of psychiatric disorders in patients with temporal lobe epilepsy (TLE). Also, ganglioglioma and dysembryoplastic neuroepithelial tumors (DNET) could represent a risk-factor for the development of post-surgical psychoses. Classically, severe psychiatric disorders contra-indicate epilepsy surgery. OBJECTIVES: Assessment of inter-ictal psychiatric disorders in 10 consecutive patients with temporal DNET, before and after epilepsy surgery with a minimum of a 2-year follow-up evaluation. METHODS: DNETs were confirmed on histological examination. Psychiatric disorders were classified according to the DSM-IV-TR. RESULTS: Five patients presented inter-ictal psychiatric disorders with, according to the DSM-IV-TR, undifferentiated schizophrenia (one case), "borderline" personality (two cases), intermittent explosive disorder with slight mental retardation (one case), and personality disorders not otherwise specified but with some traits of dependent personality and with mythomania (one case). The condition of these five patients dramatically improved after surgery. No psychiatric behavior or "de novo" psychosis was observed after surgery in any of the patients. CONCLUSION: The prevalence of inter-ictal psychiatric disorders appears to be high in epileptic patients with a temporal lobe DNET primarily in relation to personality and behavioral problems with some degree of impulsivity and verbal aggressiveness. The improvements after surgery suggest that this therapy could be performed in these patients and severe psychiatric disorders do not contra-indicate this procedure.

Extragenetic factors and clinical penetrance of DYT1 dystonia: an exploratory study.

Factors modifying the clinical penetrance of DYT1 dystonia are incompletely defined. Particularly, the contribution of extragenetic factors has been subject to only limited investigation and remains largely unexplored. A possible effect of childhood infections has been proposed, and the effect of other factors, such as perinatal adversity and trauma, has not been systematically investigated. We performed an exploratory analysis of the exposure to perinatal adversity, childhood infections, general anaesthesia and trauma comparing 39 manifesting carriers of the ∆GAG mutation, 23 non-manifesting carriers and 48 non-carriers from a multi-centre European series of 28 families with DYT1 dystonia, by means of a self-completed questionnaire and clinical interview. Detailed information on perinatal adversities (pre-term birth, complications at natural delivery, urgent caesarean section), previous childhood infections, and prior general anaesthesia or physical trauma was recorded. A positive association between a history of complications of vaginal delivery and manifestation of dystonia was detected, which was not confounded by age, gender, or education level (odds ratio 8.47, 95 % confidence interval 1.45-49.4, p = 0.02). We could not observe any significant association between presence of dystonia and the other investigated variables. Comparing non-manifesting carriers to non-carriers, the presence of the ∆GAG mutation per se was not associated with any of the environmental exposures explored. Perinatal adversities might modulate the clinical penetrance of DYT1 dystonia; their interaction with known genetic factors modifying penetrance of this condition should be investigated in new, larger collaborative studies.

Wicket spikes misinterpreted as focal abnormalities in idiopathic generalized epilepsy with prescription of carbamazepine leading to paradoxical aggravation.

Wicket spikes (WS) are a normal variant EEG pattern that sometimes can be mistaken for epileptiform activity. We present a patient with WS and idiopathic generalized epilepsy who had been wrongly diagnosed with focal epilepsy, which leads to the prescription of carbamazepine with severe aggravation of generalized tonic-clonic seizures. She was referred for presurgical assessment of refractory focal epilepsy but long-term video-EEG showed sharp theta waves over the temporal regions during awakening, with a typical aspect of WS during drowsiness, nREM sleep stages I-II, and rapid eye movements (REM) sleep. There were a few generalized spike-waves during sleep but interictal changes were increased in frequency at awakening with bursts of fast-generalized spike-waves. Carbamazepine was progressively withdrawn and the patient was progressively switched to zonisamide. The patient no longer complained of generalized tonic-clonic seizures. At one year follow-up, this patient receives zonisamide with valproate. She has remained seizure-free.

[Insulinoma presenting as pseudo-drug-resistant focal epilepsy]. / Un insulinome se présentant comme une épilepsie focale pharmacorésistante.

INTRODUCTION: We describe a case of insulinoma presenting as a refractory frontal lobe epilepsy in a 44-year-old man with a history of severe head trauma. CASE REPORT: Despite escalating treatment, his seizure frequency worsened during the previous year. He also developed psychomotor slowing and sweating occurring early in the morning. He gained weight. Insulinoma was diagnosed based on the presence of episodes of hypoglycemia, abnormal insulin/blood glucose ratio and a tumor in the pancreas (echo-ultrasound). After partial pancreatectomy, the patient became seizure free and anti-epileptic drugs were progressively stopped, with a follow-up of five years. CONCLUSION: Insulinoma should be considered in patients with no reason for having drug-resistant epilepsy, especially when seizures occur early in the morning or when episodes of neuropsychiatric symptoms with sweating are present.

[Juvenile myoclonic epilepsy in a patient with history of infantile hemiplegia]. / Epilepsie myoclonique juvénile chez une patiente atteinte d'hémiplégie infantile.

INTRODUCTION: The 1989 International Classification of Epilepsies and Related Syndromes considers normal cognitive, neurologic and anatomic findings to be prerequisites for the diagnosis of idiopathic forms of epilepsy. CASE REPORT: We report the case of a woman with juvenile myoclonic epilepsy (JME) and a history of infantile hemiplegia. When she was a teenager, she had two generalized tonic-clonic seizures, later followed by a few seizures with loss of consciousness misinterpreted as complex partial seizures. Physical examination revealed right hemiparesis. A CT scan documented a left rolandic infarction and a wrong diagnosis of focal epilepsy was made. At 20 years, a nap video-EEG was performed. A burst of generalized spike-waves was recorded on awakening. Photic stimulation and watching a Japanese cartoon on television disclosed a marked photoparoxysmal response associated with myoclonic jerks. Myoclonic jerks were in fact known by the patients but unreported. She had jerks on roads with trees due to shade/sunlight alternance. A diagnosis of JME was made. CONCLUSION: This observation illustrates that patients' situation with a presumed genetic predisposition for JME are at equal risk for brain lesions as others subjects. Misdiagnosis of focal epilepsy may have dramatic consequences in patient with JME, as some patients will be aggravated by inadequate antiepileptic drugs.

[Atypical pseudotumoral neuromeningeal cryptococcosis in an immunocompromised patient treated for pontine glioma. Case report and literature review]. / Cryptococcose neuroméningée pseudotumorale chez une enfant immunodéprimée traitée pour un gliome infiltrant du tronc cérébral. A propos d'un cas et revue de la littérature.

BACKGROUND AND PURPOSE: We report an atypical feature of neuromeningeal cryptococcosis presenting as spinal cystic arachnoiditis and cerebellar cryptococcoma in a child treated for pontine glioma. CASE REPORT: In November 2003, we diagnosed a pontine glioma in a six-year-old female child. She was initially treated with radiotherapy (54Gy for six weeks) and dexamethasone until July 2006. From January 2004 to September 2006, the patient received 30 cycles of chemotherapy including vincristine 1.5mg/m(2) Day 1, carboplatin 150mg/m(2) Day 1, and temozolomide 150mg/m(2) Days 2-6 every 28 days. In October 2006, the patient suffered spontaneous acute low back pain radiating into both lower limbs revealing lumbar cystic arachnoiditis and cerebellar cryptococcoma. The cerebrospinal fluid (CSF) sample showed lymphocytic pleocytosis and Cryptococcus neoformans; glucose and protein levels were low. First-line medical treatment including liposomal amphotericin B, then fluconazole effectively decreased the pain. However, in February 2007, she presented with cauda equina syndrome and the spinal MRI showed that the lumbar cyst had increased in size. The patient underwent a lumbar laminectomy and cyst removal. Histology confirmed the arachnoiditis with no cancer cells or pathogenic agents. CONCLUSIONS: Arachnoiditis and cryptococcoma are rare. They can appear to be a brain neoplasm because of their pseudotumoral aspect. Often, the diagnosis can be made from the CSF sample.

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.

[Epilepsy surgery in France]. / La chirurgie de l'épilepsie en France Evaluation de l'activité

We report here the results of the first survey on epilepsy surgery activity in France. Data from a questionnaire sent to 17 centers practicing epilepsy surgery were analyzed. All centers responded; however, all items were not completely documented. Over 50 years, more than 5000 patients have been operated on for drug-resistant epilepsy and more than 3000 patients underwent some invasive monitoring, most often SEEG. Currently, nearly 400 patients (including more than 100 children) are operated on yearly for epilepsy in France. Over a study period varying among centers (from two to 20 years; mean, 9.5 years), results from more than 2000 patients including one-third children were analyzed. Important differences between adults and children, respectively, were observed in terms of location (temporal: 72% versus 4.3%; frontal: 12% versus 28%; central: 2% versus 11%), etiology (hippocampal sclerosis: 41% versus 2%; tumors 20% versus 61%); and procedures (cortectomy: 50% versus 23%; lesionectomy: 8% versus 59%), although overall results were identical (seizure-free rates following temporal lobe surgery: 80.6% versus 79%; following extratemporal surgery: 65.9% versus 65%). In adults, the best results were observed following temporomesial (TM) resection associated with hippocampal sclerosis or other lesions (class I: 83% and 79%, respectively), temporal neocortical (TNC) lesional (82%), while resections for cryptogenic temporal resections were followed by 69% (TM) and 63% (TNC) class I outcome. Extratemporal lesional resections were associated with 71% class I outcome and cryptogenic 43%. In children, the best results were obtained in tumor-associated epilepsy regardless of location (class I: 80%). A surgical complication occurred in 8% after resective surgery - with only 2.5% permanent morbidity - and 4.3% after invasive monitoring (mostly hemorrhagic). Overall results obtained by epilepsy surgery centers were in the higher range of those reported in the literature, along with a low rate of major surgical complications. Growing interest for epilepsy surgery is clearly demonstrated in this survey and supports further development to better satisfy the population's needs, particularly children. Activity should be further evaluated, while existing epilepsy surgery centers as well as healthcare networks should be expanded.

[Visual auras in idiopathic generalized epilepsy]. / Auras visuelles dans les épilepsies généralisées idiopathiques.

Visual auras are reported to be uncommon or rare in patients with idiopathic generalized epilepsy. We describe three patients who experienced visual auras just before generalized tonic-clonic seizures. This study indicates that in idiopathic generalized epilepsy, visual auras manifest as flashes, lighting or the impression of seeing the sun. Unlike auras in occipital lobe epilepsy, they are very brief.

Is the early-onset torsion dystonia (EOTD) linked to TOR1A gene as frequent as expected in France?

Early onset torsion dystonia are rare movement disorders. Molecular defect is known for only a subgroup, consisting of a unique and recurrent mutation in the TOR1A gene. We undertook a nationwide census of French TOR1A-mutation carriers and the assessment of clinical associated signs. Overall, 53 index cases and 104 relatives were studied and haplotypes linked to the mutation constructed. The previously reported Ashkenazi-Jewish haplotype was found in 11 families with the remainder carrying distinct haplotypes suggesting independent mutation events. This study demonstrates the scarcity of this disease in France with estimated disease frequency of 0.13:100,000 and mutation frequency of 0.17:100,000.

[Carbamazepine and clarithromycin: a clinically relevant drug interaction]. / Carbamazépine et clarithromycine: une interaction médicamenteuse cliniquement significative.

BACKGROUND: Carbamazepine is associated with clinically relevant drug interactions especially with macrolide antibiotics such as troleandomycin and erythromycin. These drugs inhibit the metabolism of carbamazepine. Clarithromycin, a macrolide antibiotic similar to erythromycin, is widely used to treat respiratory tract infections and is used for the treatment of atypical mycobacterial infections and Helicobacter pylori-associated peptic ulcer disease. METHODS: To report an interaction between carbamazepine and clarithromycin, we present a study that includes three regular attenders at the epilepsy department of Montpellier and seven cases reported by the French national drug safety center. RESULTS: In patients receiving carbamazepine alone or in combination with other drugs, administration of clarithromycin led to a transitory overdosage (ataxia, dizziness, diplopia, nausea, vomiting, drowsiness). Blood level was available in 8 patients with a concentration of carbamazepine ranging from 13.3 to 28.5 mg/l. CONCLUSION: Carbamazepine is extensively metabolized by cytochrome P450 enzymes, especially CYP34A. As clarithromycin is also metabolized by CYP3A4, this drug has the propensity to inhibit the metabolism of carbamazepine. Clarithromycin should be thus avoided in patients taking carbamazepine.

Chiari malformation and sleep related breathing disorders.

OBJECTIVE: To estimate the frequency, mechanisms and predictive factors of sleep apnoea syndrome (SAS) in a large group of children and adults with type I (CMI) and II (CMII) Chiari malformation (CM). BACKGROUND: The anatomical and functional integrity of both respiratory circuits and lower cranial nerves controlling the upper airway is necessary for breathing control during sleep. These latter structures may be altered in CM, and a few investigations have reported CM related sleep disordered breathing. METHODS: Forty-six consecutive unrelated patients with CM (40 CMI, six CMII), of which 20 were children (eight males) and 26 were adults (12 males), underwent physical, neurological and oto-rhino-laryngoscopic examination, MRI and polysomnography. RESULTS: SAS was present in 31 (67.4%) of the patients with CM (70% of CMI, 50% of CMII, including mainly children). Sixty per cent of children with CM exhibited SAS, including 35% with obstructive (OSAS) and 25% with central (CSAS) sleep apnoea syndrome. SAS was observed in 73% of CM adults (57.7% OSAS, 15.4% CSAS). Severe SAS was found in 23% of CM adults. Multiple regression analysis revealed that age, type II Chiari and vocal cord paralysis predicted the central apnoea index. CONCLUSION: SAS is highly prevalent in all age groups of patients suffering from CM. CSAS, a rare condition in the general population, was common among the patients with CM in our study. Sleep disordered breathing associated with CM may explain the high frequency of respiratory failures observed during curative surgery of CM. Our results suggest that SAS should be systematically screened for in patients with CM, especially before surgery.

[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

Lamotrigine associated with exacerbation or de novo myoclonus in idiopathic generalized epilepsies.

Five patients with idiopathic generalized epilepsies (IGE) treated with lamotrigine (LTG) experienced exacerbation or de novo appearance of myoclonic jerks (MJ). In three patients, LTG exacerbated MJ in a dose-dependent manner with early aggravation during titration. MJ disappeared when LTG dose was decreased by 25 to 50%. In two patients, LTG exacerbated MJ in a delayed but more severe manner, with myoclonic status that only ceased after LTG withdrawal.