Extradural malignant rhabdoid tumor of the spine in children: A case-based review.

BACKGROUND: Extradural malignant rhabdoid tumors of the spine are highly malignant and invasive tumors (WHO grade IV) with poor prognosis, most frequently occurring in young children before 2 years of age. Pain and motor deficit are the most common presenting signs. CASE DESCRIPTION: We report a case of a 2-year-old girl presenting with axial ataxia and paraparesis related to an extradural malignant rhabdoid tumor causing posterior thoracic spinal cord compression (D3-D6). She underwent two near-total removal of the tumor, adjuvant chemotherapy according to the Eu-Rhab protocol and proton beam therapy. She then developed multiple cranial nerve paresis (meningeal carcinomatosis) after 4 cycles of chemotherapy and died at 4.32 months of follow-up. DISCUSSION AND CONCLUSION: The role of the PET scan was essential to guide us to remove a residue, while two concomitant spinal MRIs were considered negative. We reviewed the 16 cases reported in the literature. Multiple surgeries and radiotherapy seem to be correlated with longer survival. No child younger than 2 years old had a documented survival higher than 4.32 months.

Complete Resection of a Torcular Herophili Hemangiopericytoma without Sinus Reconstruction: A Case Report and Review of the Literature.

A 78-year-old woman presented to the emergency department with mild headaches and a sudden onset of blurred vision. Computerized tomography scan and magnetic resonance imaging showed what was described at first as a meningioma invading and occluding the torcular Herophili, the posterior third of the superior sagittal sinus and the proximal part of the right transverse sinus. Gross total resection of the tumor was performed without reconstructing dural sinuses. The patient was discharged home without new neurological deficit. Histopathology was in favor of a hemangiopericytoma Grade II World Health Organization (WHO). Total body positron emission tomography [18F]fluorodeoxyglucose found no secondary location. Radiotherapy was planned post-operatively.

Vagus Nerve Stimulation Elicits Sleep EEG Desynchronization and Network Changes in Responder Patients in Epilepsy.

Neural desynchronization was shown as a key mechanism of vagus nerve stimulation (VNS) action in epilepsy, and EEG synchronization measures are explored as possible response biomarkers. Since brain functional organization in sleep shows different synchrony and network properties compared to wakefulness, we aimed to explore the effects of acute VNS on EEG-derived measures in the two different states of vigilance. EEG epochs were retrospectively analyzed from twenty-four VNS-treated epileptic patients (11 responders, 13 non-responders) in calm wakefulness and stage N2 sleep. Weighted Phase Lag Index (wPLI) was computed as connectivity measure of synchronization, for VNS OFF and VNS ON conditions. Global efficiency (GE) was computed as a network measure of integration. Ratios OFF/ON were obtained as desynchronization/de-integration index. Values were compared between responders and non-responders, and between EEG states. ROC curve and area-under-the-curve (AUC) analysis was performed for response classification. In responders, stronger VNS-induced theta desynchronization (p < 0.05) and decreased GE (p < 0.05) were found in sleep, but not in wakefulness. Theta sleep wPLI Ratio OFF/ON yielded an AUC of 0.825, and 79% accuracy as a response biomarker if a cut-off value is set at 1.05. Considering all patients, the VNS-induced GE decrease was significantly more important in sleep compared to awake EEG state (p < 0.01). In conclusion, stronger sleep EEG desynchronization in theta band distinguishes responders to VNS therapy from non-responders. VNS-induced reduction of network integration occurs significantly more in sleep than in wakefulness.

Vagus Nerve Stimulation-Induced Laryngeal Motor Evoked Potentials: A Possible Biomarker of Effective Nerve Activation.

Vagus nerve stimulation (VNS) therapy is associated with laryngeal muscle activation and induces voice modifications, well-known side effects of the therapy resulting from co-activation of the recurrent laryngeal nerve. In this study, we describe the non-invasive transcutaneous recording of laryngeal motor evoked potentials (LMEPs), which could serve as a biomarker of effective nerve activation and individual titration in patients with drug-resistant epilepsy. We recruited drug-resistant epileptic patients treated for at least 6 months with a VNS. Trains of 600-1200 VNS pulses were delivered with increasing current outputs. We placed six skin electrodes on the ventral surface of the neck, in order to record LMEPs whenever the laryngeal muscular threshold was reached. We studied the internal consistency and the variability of LMEP recordings, and compared different methods for amplitude calculation. Recruitment curves were built based on the stimulus-response relationship. We also determined the electrical axis of the LMEPs dipole in order to define the optimal electrode placement for LMEPs recording in a clinical setting. LMEPs were successfully recorded in 11/11 patients. The LMEPs threshold ranged from 0.25 to 1 mA (median 0.50 mA), and onset latency was between 5.37 and 8.77 ms. The signal-to-noise ratio was outstanding in 10/11 patients. In these cases, excellent reliability (Intraclass correlation coefficient, ICC > 0.90 across three different amplitude measurements) was achieved with 10 sample averages. Moreover, our recordings showed very good internal consistency (Cronbach's alpha > 0.95 for 10 epochs). Area-under-the-curve and peak-to-peak measurement proved to be complementary methods for amplitude calculation. Finally, we determined that an optimal derivation requires only two recording electrodes, aligned on a horizontal axis around the laryngeal prominence. In conclusion, we describe here an optimal methodology for the recording of VNS-induced motor evoked responses from the larynx. Although further clinical validation is still necessary, LMEPs might be useful as a non-invasive marker of effective nerve activation, and as an aid for the clinician to perform a more rational titration of VNS parameters.

Postoperative spinal adhesive arachnoiditis presenting with hydrocephalus and cauda equina syndrome.

To our knowledge, the association between hydrocephalus and postoperative spinal adhesive arachnoiditis (SAA) has never been reported. Herein we describe an unusual case of a 45-year-old man with spinal adhesive arachnoiditis (SAA) who developed delayed-onset hypertensive hydrocephalus and cauda equina syndrome (CES) after multiple low-back surgeries. The patient's clinical presentation, imaging findings, surgical management, and the possible mechanisms are discussed in the light of the present literature.

Early experiences with tachycardia-triggered vagus nerve stimulation using the AspireSR stimulator.

Many epilepsy patients treated with vagus nerve stimulation additionally use an "on-demand" function, triggering an extra stimulation to terminate a seizure or diminish its severity. Nevertheless, a substantial number of patients are not able to actively trigger stimulations by use of a magnet, due to the absence of an aura or inability for voluntary actions in the early phase of a seizure. To address this need, a novel implantable pulse generator, the AspireSR VNS system, was developed to provide automated ictal stimulation triggered by a seizure-detecting algorithm. We report our experience with three patients in assessing the functionality of ictal stimulation, illustrating the detection system in practice. Detection of ictal tachycardia and variable additional detections of physiological tachycardia depended on the individual seizure-detecting algorithm settings.

A prospective, multicenter study of cardiac-based seizure detection to activate vagus nerve stimulation.

PURPOSE: This study investigates the performance of a cardiac-based seizure detection algorithm (CBSDA) that automatically triggers VNS (NCT01325623). METHODS: Thirty-one patients with drug resistant epilepsy were evaluated in an epilepsy monitoring unit (EMU) to assess algorithm performance and near-term clinical benefit. Long-term efficacy and safety were evaluated with combined open and closed-loop VNS. RESULTS: Sixty-six seizures (n=16 patients) were available from the EMU for analysis. In 37 seizures (n=14 patients) a ≥ 20% heart rate increase was found and 11 (n=5 patients) were associated with ictal tachycardia (iTC, 55% or 35 bpm heart rate increase, minimum of 100 bpm). Multiple CBSDA settings achieved a sensitivity of ≥ 80%. False positives ranged from 0.5 to 7.2/h. 27/66 seizures were stimulated within ± 2 min of seizure onset. In 10/17 of these seizures, where triggered VNS overlapped with ongoing seizure activity, seizure activity stopped during stimulation. Physician-scored seizure severity (NHS3-scale) showed significant improvement for complex partial seizures (CPS) at EMU discharge and through 12 months (p<0.05). Patient-scored seizure severity (total SSQ score) showed significant improvement at 3 and 6 months. Quality of life (total QOLIE-31-P score) showed significant improvement at 12 months. The responder rate (≥ 50% reduction in seizure frequency) at 12 months was 29.6% (n=8/27). Safety profiles were comparable to prior VNS trials. CONCLUSIONS: The investigated CBSDA has a high sensitivity and an acceptable specificity for triggering VNS. Despite the moderate effects on seizure frequency, combined open- and closed-loop VNS may provide valuable improvements in seizure severity and QOL in refractory epilepsy patients.

Intravenous magnesium sulfate administration in a patient with refractory vasospasm following subarachnoid hemorrhage.

OBJECTIVE: Magnesium sulfate is being investigated for the prevention or treatment of vasospasm following subarachnoid hemorrhage. PATIENT: A 45-year-old woman suffered subarachnoid hemorrhage and developed after 8 days symptomatic vasospasm in the left middle cerebral artery (MCA) while she was receiving nimodipine prophylactically. METHODS AND RESULTS: Transcranial Doppler monitoring was performed. Cerebral autoregulation was abolished in the left MCA. Despite this finding the administration of a bolus dose of MgSO(4), followed by a continuous infusion in order to achieve serum magnesium levels in the range of 4-4.5 mg/dl (1.65-1.85 mmol/l), resulted in a marked decrease (12.2%) of the left MCA mean blood flow velocity, without clinically relevant change in systemic blood pressure (3%). This effect was maintained for at least 4 h. It did not prevent the development of ischemic lesions.

Spinal dural arteriovenous fistula presenting with paraplegia following lumbar puncture.

Spinal dural arteriovenous fistulas are rare lesions with an annual incidence of 1 per 100,000 population. In patients with this disease, an abnormal vascular dural shunt exists between a dural branch of a segmental artery and a subdural radicular vein that drains the perimedullary venous system, leading to venous hypertension and secondary congestive myelopathy. Generally, patients present with progressive paraparesis, urinary disturbances, and gait ataxia. In this report the authors describe a 61-year-old woman with a spinal dural arteriovenous fistula who developed an acute paraplegia after a nontraumatic lumbar puncture. The possible underlying mechanisms and treatment options are discussed.

Motor cortex stimulation in a three-year-old child with trigeminal neuropathic pain caused by a malignant glioma in the cerebellopontine angle: case report.

BACKGROUND AND IMPORTANCE: Motor cortex stimulation (MCS) is an accepted treatment in neuropathic pain syndromes. Use of MCS for trigeminal neuropathic pain (TNP) caused by a malignant glioma or in a child has not previously been reported in the literature. CLINICAL PRESENTATION: A 3-year-old boy presented to our department with a right temporal tumor with extension into the cavernous sinus and along the root of the trigeminal nerve up to the protuberance. Six weeks after removal of the temporal part of the tumor, the patient developed medically refractory trigeminal pain associated with tumor progression into the posterior fossa. We decided to remove the tumor from the cerebellopontine angle and residual tumor in the pericavernous area and then gave postoperative radio- and chemotherapy. Five months later, the patient developed unbearable refractory neuropathic pain characterized by a burning sensation in the first and second trigeminal areas. After a multidisciplinary discussion, MCS was recommended. We performed subdural MCS after localization of the central sulcus via anatomic landmarks, neuronavigation, peroperative sensory evoked potentials, and motor evoked potentials. The mother estimated a 75% reduction in the child's pain at 48 hours postoperatively, which continued until the child was pain-free. CONCLUSION: MCS is a minimally invasive surgical technique that seems to be a potential treatment for carefully selected children experiencing very severe and medically refractory neuropathic pain, even in the context of a neoplasm.

Delayed compressive angiomatous degeneration in a case of mesial temporal lobe epilepsy treated by γ knife radiosurgery: case report.

OBJECTIVE: Mesial temporal lobe epilepsy (MTLE) is one of the most common causes of intractable partial epilepsy. The conventional treatment of patients with MTLE is surgical excision. Currently, gamma knife (GK) radiosurgery is being explored as an alternative treatment. We report the first delayed major complication related to this treatment. CLINICAL PRESENTATION: A 54-year-old woman with a medical history of a post-viral encephalitis in childhood was treated in April 2001 by GK radiosurgery for a medically refractory MTLE. Her right temporomesial area received a dose of 20 Gy at the 50% marginal isodose line. Unfortunately, the patient continued to experience seizures, although they were of shorter duration and occurred less frequently. She was seen in our department on November 8, 2007, for an intracranial hypertensive syndrome. The imaging work-up showed an expansive hemorrhagic lesion in the right mesiotemporal area. Despite corticosteroid treatment, the patient still complained about headaches on November 13, and surgery was scheduled for November 22. However, the patient returned to the emergency department on November 16 with a temporal herniation syndrome requiring an urgent surgical procedure. INTERVENTION: The expansive lesion was completely removed. Histologic examination revealed lesions of the gray and white matter consisting of severe gliosis, hemorrhagic foci, hyalinized vessels, and neovascularization, giving the brain parenchyma an angiomatous aspect. CONCLUSION: Although reports on GK radiosurgical treatment of MTLE are encouraging, this case stresses the risk of developing 6 years later an angiomatous degeneration of the targeted brain with life-threatening intracranial hypertension.