Endoscopic Third Ventriculostomy in the Fourth Ventricle Outlet Obstruction Associated with Chiari Malformation Type I and Syringomyelia: Case Report.

Hydrocephalus by the fourth ventricle outlet obstruction (FVOO) associated with a Chiari malformation type I and syringomyelia is a well-known entity but a rare situation in clinical practice. Although suboccipital craniectomy with the opening of the obstruction membrane appears to be the most physiological approach, by restoring the original pathway of cerebrospinal fluid flow, the endoscopic third ventriculostomy (ETV) represents an important minimally invasive alternative. We report the case of an adult patient with tetra ventricular hydrocephalus by FVOO associated with Chiari malformation and syringomyelia. The ETV alone completely resolved all symptoms, as well as neuroimaging abnormalities on the control magnetic resonance imaging. The ETV is a minimally invasive option for the treatment of hydrocephalus in patients with obstruction at the exit of the fourth ventricle, even in cases associated with Chiari malformation and syringomyelia.

A Rare Cause of Thoracic Spinal Cord Compression by Multiple Large Tarlov Cysts.

Spinal extradural arachnoid cyst (SEAC) is a rare cause of spinal cord compression. Bifocal location of thoracic and sacral SEACs is rarely reported in the literature. We report a case of thoracic spinal cord compression by SEAC associated with asymptomatic multiple sacral Tarlov cysts (TC). The surgical management and postoperative outcome of the patient are discussed. A 34-year-old woman was referred to the hospital for acute thoracic pain with a history of chronic long-standing back pain. She complained of walking difficulties. Neurological examination demonstrated incomplete spastic paraplegia with sensory level in T9. Magnetic resonance imaging revealed a large cystic formation from T7-11 and at the level of the sacrum. We performed laminectomies at the level of interest from T7-11. The cysts were dissected from the underlying dura after removal of the cerebrospinal fluid. We found nerve tissue in the cysts. We excised the cyst and preserved the nerve roots. Subsequently, a duraplasty was performed with autologous grafts from the lumbar fascia. The condition of the patient improved after surgery and he was recovering well at follow-up. Although the surgical treatment of TC is controversial, especially at the sacral lumbar level, decompression at the dorsal level in this case is indisputable.

[Intracranial tuberculomas in Nouakchott, Mauritania]. / Les tubérculomes intracrâniens à Nouakchott, Mauritanie.

Tuberculosis is a major public health problem in developing countries. Cerebral tuberculomas is a tuberculous granulation tissue mass restrained and limited by immune defenses of the host. This study aims to describe the characteristics and the evolutionary profile of intracranial tuberculomas in Mauritania. Data of 34 patients with intracranial tuberculoma were collected retrospectively in several hospitals in the city of Nouakchott between January 2005 and June 2017. Evolutionary features of patients under treatment were analyzed. Our retrospective study involved 20 men and 14 women (sex ratio 1.4). The average age of our patients was 28.7 years. Twelve patients were less than or equal to 16 years. Symptomatology was dominated by increased intracranial pressure and seizures in 27 cases (79.41%) and 20 cases (58.82%) respectively. Intradermo tuberculin reaction was positive in 14 (41.17%) cases. Supratentorial lesion was found in 24 patients (70.58%). In all patients, therapeutic approach was based on multidrug chemotherapy for a period greater than or equal to 12 months. Surgical procedure was performed in 12 patients (35.29%). Outcome was favorable with complete healing without sequelae in 23 cases, reflecting a rate of 67.64%. Given the non-specific role of imaging exams in the diagnosis of intracranial tuberculoma and the lack of the stereotactic biopsy in our Country where the disease is endemic, we recommend to perform a two-month therapeutic test in patients with suspicious lesions.

[Surgical treatment of intracranial meningiomas in Nouakchott, Mauritania]. / Prise en charge chirurgicale des méningiomes intracrâniens à Nouakchott, Mauritanie.

Meningiomas are frequently encountered tumours in neurosurgery. However, there is a paucity of data concerning their epidemiology, their clinical characteristics and their treatment compared to gliomas. This study aims to identify the epidemiological profile and to assess the quality of treatment of intracranial meningiomas (ICM) at the National Hospital Center in Nouakchott, Mauritania. We conducted a retrospective study of patients who had undergone surgery for the treatment of ICM between September 2013 and September 2016. Thirty-two patients had undergone surgery for the treatment of ICM (26.6%). The average age was 45.12 (± 13.8 years) among whom 75% were women. The average length of stay in hospital had been 13 days (± 7 days). The mean time between symptom onset and diagnosis had been 10 months (±5months). The mean size of ICM had been 5.07cm (±2.00cm) ranging from 2.5cm to 10.5cm. Complementary MRI had been performed in 46.8% of patients after brain CT scan. In our series, 38% of ICM had grown on brain convexity. The mean surgical time had been 23.91 days (±17days). The quality grade of surgical resection assigned according to Simpson score was Grade I (66%), Grade II (19%), Grade III (6%), Grade IV (9%). The histological grade assigned according to the 2007 WHO classification was Grade I (93%), Grade II-III (7%). The overall operative mortality was (n=3, 9.4%). The development of technical equipment in the department of neurosurgery, radiology and of equipment in anesthesia and intensive care will contribute to improve outcomes and to reduce mortality rates.

Wait-and-see strategy compared with proactive Gamma Knife surgery in patients with intracanalicular vestibular schwannomas.

OBJECT: The roles of the wait-and-see strategy and proactive Gamma Knife surgery (GKS) in the treatment paradigm for small intracanalicular vestibular schwannomas (VSs) is still a matter of debate, especially when patients present with functional hearing. The authors compare these 2 methods. METHODS: Forty-seven patients (22 men and 25 women) harboring an intracanalicular VS were followed prospectively. The mean age of the patients at the time of inclusion was 54.4 years (range 20-71 years). The mean follow-up period was 43.8 ± 40 months (range 9-222 months). Failure was defined as significant tumor growth and/or hearing deterioration that required microsurgical or radiosurgical treatment. This population was compared with a control group of 34 patients harboring a unilateral intracanalicular VS who were consecutively treated by GKS and had functional hearing at the time of radiosurgery. RESULTS: Of the 47 patients in the wait-and-see group, treatment failure (tumor growth requiring treatment) was observed in 35 patients (74%), although conservative treatment is still ongoing for 12 patients. Treatment failure in the control (GKS) group occurred in only 1 (3%) of 34 patients. In the wait-and-see group, there was no change in tumor size in 10 patients (21%), tumor growth in 36 patients (77%), and a mild decrease in tumor size in 1 patient (2%). Forty patients in the wait-and-see group were available for a hearing level study, which demonstrated no change in Gardner-Robertson hearing class for 24 patients (60%). Fifteen patients (38%) experienced more than 10 db of hearing loss and 2 of them became deaf. At 3, 4, and 5 years, the useful hearing preservation rates were 75%, 52%, and 41% in the wait-and-see group and 77%, 70%, and 64% in the control group, respectively. Thus, the chances of maintaining functional hearing and avoiding further intervention were much higher in cases treated by GKS (79% and 60% at 2 and 5 years, respectively) than in cases managed by the wait-and-see strategy (43% and 14% at 2 and 5 years, respectively). CONCLUSIONS: These data indicate that the wait-and-see policy exposes the patient to elevated risks of tumor growth and degradation of hearing. Both events may occur independently in the mid-term period. This information must be presented to the patient. A careful sequential follow-up may be adopted when the wait-and-see strategy is chosen, but proactive GKS is recommended when hearing is still useful at the time of diagnosis. This recommendation may be a main paradigm shift in the practice of treating intracanalicular VSs.

Recurrence of vestibular schwannomas after surgery.

The issue of recurrence of vestibular schwannomas is poorly studied by the surgical literature and is probably underestimated. Our own long-term retrospective analysis after translabyrinthine approach has indicated a 9.2% recurrence rate. This long-term event is mainly due to regrowth of microfragments that have been left in the operative field along the course of the facial nerve or at the surface of the pons. Management of recurrence depends on the tumor size and patient's condition. Our current policy is to propose a Gamma Knife radiosurgical treatment in eligible cases. Prospective long-term follow-up studies using serial MR imaging after radical removal should bring reliable data about the incidence of vestibular schwannoma recurrence.

The wait and see strategy for intracanalicular vestibular schwannomas.

To refine our therapeutic policy for intracanalicular tumors, we reviewed our series of patients who where initially treated conservatively. Forty-seven patients (22 men and 25 women) harboring an intracanalicular vestibular schwannoma were followed prospectively. Mean age at the time of inclusion was 54.4 (20-71) years. The mean follow-up period was 43.8 months (+/-40 months) ranging from 9 to 222 months. Failure was defined as significant tumor growth and/or hearing deterioration that required a microsurgical or radiosurgical treatment. Failure was observed in 35 cases while a conservative treatment is still ongoing in 12 patients. Ten patients kept an unchanged tumor size (21.3%), while 36 patients experienced a tumor growth (76.6%), and 1 patient experienced a mild decreased tumor size (2.1%). Among the 40 patients who where available for hearing level study, 24 patients (60%) did not change their Gardner and Robertson hearing class. Fifteen patients (37.5%) experienced a >10-dB hearing loss and 2 of them became deaf. One patient (2.5%) improved her hearing level from 56.3 to 43.8 dB over a 39.5-month follow-up period. These data suggest that the wait and see policy exposes the patient to degradation of hearing and tumor growth. Both events may occur in an independent way in the middle-term period. This information has to be given to the patient, and a careful sequential follow-up may be adopted when the wait and see strategy is chosen.

Hydrocephalus and vestibular schwannomas: considerations about the impact of gamma knife radiosurgery.

Hydrocephalus may occur at various stages of the natural course of vestibular schwannoma and can also be diagnosed after the therapeutic procedure. The aim of the present study was to analyze the impact of Gamma Knife radiosurgery (GKR) on previously diagnosed hydrocephalus (group A patients) and to evaluate the incidence of de novo hydrocephalus after GKR (group B patients). We reviewed retrospectively our case material and the data from the literature. Among the first 1,000 vestibular schwannoma patients treated by GKR in our institution, 30 patients (3%) belonged to group A and 1% to group B. In both groups, hydrocephalus was more often associated with the following data: Elderly, large tumor, previous MS, NF2 disease and bilateral tumors. Cerebrospinal fluid (CSF) shunting system was needed in 25% of the group A and in all of the group B patients. In this latter group, CSF shunting was justified by poor clinical tolerance, and the mean interval between GKR and CSF shunting was 14.8 months (range: 4-31 months). These data suggest that GKR does not decompensate the majority of preexisting radiological hydrocephalus. De novo post-GKR hydrocephalus is of low incidence, comparable to the postoperative rate. Generally, it comes early after GKR and justifies CSF shunting. Thus, it may be postulated that in a small subgroup of patients, GKR may disturb the normal hydrodynamic pathway. Mechanisms of such event remain controversial.

La Sclérose En Plaques En Mauritanie

Introduction. Caracterisee par une demyelinisation de la substance blanche du systeme nerveux central; la Sclerose en plaques (SEP) se manifeste cliniquement par des tableaux encephaliques et/ ou medullaires subaigus. Il existerait un gradient Nord-Sud dans la repartition de la maladie. Les populations africaines (noires en particulier) et orientales seraient moins atteintes. La Mauritanie; par la diversite ethnique de sa population et sa situation geographique (trait d'union entre ces 2 regions) peut constituer un terrain interessant pour l'etude de cette maladie. De plus l'introduction de l'IRM dans notre pratique medicale depuis juillet 2005; constitue un atout pour le diagnostic de cette affection.Objectif. Presenter des observations de patients mauritaniens dont les tableaux cliniques et les explorations etaient en faveur d'une SEP. Methode. Nous avons selectionne 4 observations de malades hospitalises dans le Service de Neurologie du Centre Neuropsychiatrique de Nouakchott en Mauritanie; en 2005. Apres un examen clinique neurologique; ils avaient beneficie d'une exploration par IRM. Resultats. Le plus jeune de notre serie a 17 ans et le plus age 55 ans. Tous les patients etaient d'ethnie maure; trois etaient de race noire et un etait de race blanche. Tous ont presente des signes fortement evocateurs de SEP. Nous avons observe une forme d'emblee progressive; deux formes remittentes; et une premiere poussee chez une jeune fille. Les resultats de l'IRM cerebrale chez les 4 patients et de l'IRM medullaire chez trois patients ont montre des plaques de demyelinisation. Un seul patient pu avoir l'electrophorese des proteines du LCR qui a permis de montrer une distribution oligoclonale