Neurophysiological biomarkers to optimize deep brain stimulation in movement disorders.

Intraoperative neurophysiological information could increase accuracy of surgical deep brain stimulation (DBS) lead placement. Subsequently, DBS therapy could be optimized by specifically targeting pathological activity. In Parkinson's disease, local field potentials (LFPs) excessively synchronized in the beta band (13-35 Hz) correlate with akinetic-rigid symptoms and their response to DBS therapy, particularly low beta band suppression (13-20 Hz) and high frequency gamma facilitation (35-250 Hz). In dystonia, LFPs abnormally synchronize in the theta/alpha (4-13 Hz), beta and gamma (60-90 Hz) bands. Phasic dystonic symptoms and their response to DBS correlate with changes in theta/alpha synchronization. In essential tremor, LFPs excessively synchronize in the theta/alpha and beta bands. Adaptive DBS systems will individualize pathological characteristics of neurophysiological signals to automatically deliver therapeutic DBS pulses of specific spatial and temporal parameters.

Calcium pyrophosphate deposition disease of the temporomandibular joint.

Calcium pyrophosphate dihydrate deposition disease (CPDD, tophaceous pseudogout) is a rare crystal arthropathy characterized by calcium pyrophosphate crystal deposition in joint spaces, episodes of synovitis, and radiological features of chondrocalcinosis. We present a case of 61-year-old woman who presented with left temporomandibular joint (TMJ) pain, difficulty chewing, left facial numbness, left-sided hearing loss, and left TMJ swelling. Imaging of the temporal fossa revealed a large mass emanating from the temporal bone at the TMJ, extending into the greater wing of the sphenoid and involving the mastoid bone and air cells posteriorly. Fine needle aspiration demonstrated polarizable crystals with giant cells. Intraoperatively, the TMJ was completely eroded by the mass. Final pathology was consistent with tophaceous pseudogout. CPDD has rarely been reported involving the skull base. None of the cases originally described by McCarty had TMJ pseudogout. Symptoms are generally pain, swelling, and hearing loss. Management is nearly always surgical with many patients achieving symptomatic relief with resection. CPDD is associated with many medical problems (including renal failure, gout, and hyperparathyroidism), but our patient had none of these risk factors. This case demonstrates that CPDD can involve the skull base and is best treated with skull base surgical techniques.

Stereotactic radiosurgery for glioblastoma: retrospective analysis.

PURPOSE: This retrospective study was done to better understand the conditions for which stereotactic radiosurgery (SRS) for glioblastoma may be efficacious. METHODS: Between 2000 and 2007, 33 patients with a pathological diagnosis of glioblastoma received SRS with the Novalis Shaped Beam Radiosurgery system. Eighteen patients (54%) underwent salvage SRS for recurrence while 15 (45%) patients received upfront SRS following standard fractionated RT for newly diagnosed glioblastoma. RESULTS: There were no RTOG grade >2 acute side effects. The median survival after SRS was 6.7 months (range 1.4 - 74.7). There was no significant difference in overall survival (from the time of initial diagnosis) with respect to the timing of SRS (p = 0.2). There was significantly better progression free survival in patients treated with SRS as consolidation versus at the time of recurrence (p = 0.04). The majority of patients failed within or at the margin of the SRS treatment volume (21/26 evaluable for recurrence). CONCLUSION: SRS is well tolerated in the treatment of glioblastoma. As there was no difference in survival whether SRS is delivered upfront or at recurrence, the treatment for each patient should be individualized. Future studies are needed to identify patients most likely to respond to SRS.

Effect of treatment of elevated blood pressure on neurological deterioration in patients with acute intracerebral hemorrhage.

INTRODUCTION: Treatment of elevated blood pressure after acute intracerebral hemorrhage (ICH) is controversial. There is a risk of hematoma expansion with elevated blood pressure, and risk of ischemia with blood pressure control. This study was done to determine the effect of blood pressure control on outcome. METHODS: We retrospectively studied 122 patients with ICH. We collected 24-h blood pressure readings on all patients. The Glasgow Coma Score (GCS) at baseline and at 24 h was used to determine neurological deterioration (GCS decline > or = 2). Baseline computerized tomography (CT) scans were reviewed for hematoma volume, intraventricular hemorrhage, and location of hemorrhage. Drops in systolic blood pressure and mean arterial pressures over 24 h were divided in quartiles to determine the risk of neurological deterioration among quartiles. A logistic regression model was used to determine the association between variables of interest and neurological deterioration. RESULTS: Neurological deterioration was observed in 12 patients (10%). Baseline blood pressure and GCS were only two variables significantly different among quartiles of blood pressure drop. Multivariable adjusted analysis for these variables demonstrated significant trend toward reduced neurological deterioration with maximum blood pressure drop (systolic or mean). The risk of neurological deterioration was significantly lower in the quartile of maximum drop of systolic (odds ratio [OR] 0.02, 95% confidence interval [CI] 0.0-0.68) or mean (OR 0.03, 95% CI 0.0-0.98) blood pressure when compared to the quartile with least drop. CONCLUSION: This study supports that reduction of blood pressure in patients with acute ICH is safe and suggests that aggressive reduction might reduce the risk of neurological deterioration in first 24 h of admission.