Electroencephalographic and behavioral alterations produced by delta-1-tetrahydrocannabinol.

The administration of small doses of Delta(l)-tetrahydrocannabinol to cats with indwelling electrodes produced a disruption of both the electroencephalogram and behavior. Some of these alterations, including the appearance of a high-voltage slow wave electroencephalogram in the awake and moving animal, have been observed in cats that had been administered other drugs known to cause hallucinogenic states in man.

Herniated lumbar disc disease in patients with malignancy.

Six patients with cancer presented with signs and symptoms of a lumbar herniated disc syndrome due to a herniated lumbar disc. The differential diagnosis and literature are reviewed. In four of the six, the patients' complaints were attributed to the malignancy, with delay in diagnosis and institution of appropriate therapy. In two of the patients, treatment was administered for presumed spinal metastasis with radiation therapy and/or chemotherapy with castration before the correct diagnosis was made. Surgery was performed on all six patients confirming the diagnosis of a herniated lumbar disc at the involved level and relieving the patients' pain.

Complications associated with Ommaya reservoirs in patients with cancer. The Princess Margaret Hospital experience and a review of the literature.

The complications associated with the use of Ommaya reservoirs in 106 patients with meningeal involvement due to malignant disease are reviewed. Twenty-seven patients had acute lymphoblastic leukemia, 12 acute myelogenous leukemia, 3 chronic lymphocytic leukemia, 34 lymphoma, 29 carcinoma, and 1 chronic myelocytic leukemia. There were 11 technical complications, including 1 death due to misplacement of the catheter, 2 mild intraventricular hemorrhages, and 5 malfunctioning reservoirs; 3 required craniotomies (1 for subdural hematoma and 2 for subdural hygroma); 13 cases of bacterial meningitis occurred in 10 patients. One patient died of Staphylococcus aureus meningitis. The organisms causing the other infections were mainly coagulase-negative staphylococci (8 cases) or Propionibacterium acnes (2 cases). The projected infection rate for all patients (by Kaplan-Meier analysis) during the first year following insertion of a reservoir was 15%. Successful use of Ommaya reservoirs requires expert surgical implantation and meticulous care during accessing to minimize complications.

Analysis of facial displays and verbal report to assess subjective state in the non-invasive detection of limbic system activation by procaine hydrochloride.

The problem of scalp EEG as a measure of cortical or subcortical activity is particularly relevant to complex partial seizures as the abnormal discharging is frequently limbic in origin [14, 30]. Livingston [38] has suggested that administration of intravenous procaine as a limbic activator and cortical suppressor would be of utility in diagnosing limbic involvement in complex partial seizures. While there is considerable evidence derived from experimental animal models that procaine hydrochloride is a limbic system activator that acts preferentially on subcortical epileptic foci at lower doses than on less active epileptic foci or non-epileptic tissue [2, 4], it was necessary to demonstrate that procaine activates the human limbic system. The non-invasive approach taken in the present study was to compare the published effects of direct electrical stimulation of the human limbic system [31] to the behavioural and subjects effects of intravenous procaine administration. The areas in which we obtained the most robust procaine effects (hallucinations, emotions and alimentary sensations) were also Halgren et al.'s [31] most repeatable effects. The correspondence between electrical stimulation effects and procaine administration effects was striking - with verbal report by patients matching exactly in many instances. Furthermore, analysis of facial displays proved useful in providing access to subjects state fluctuations which would otherwise have gone undetected. The data provide strong evidence that procaine hydrochloride can be used as a human limbic system activator. Future research will investigate the clinical and diagnostic significance of differential response to procaine.

Spinal fixation after anterior decompression for symptomatic spinal metastasis.

Surgical strategies for the treatment of symptomatic spinal metastases must take into account both decompression of the spinal cord and stabilization of the spinal column. A method is described for securing spinal stabilization in patients who have undergone surgical decompression for symptomatic spinal metastases by an anterior approach. The fixation device used is a tailor-made prosthesis consisting of a U-shaped stainless steel plate permitting screw fixation to secure axial and rotational stability with an interposed methyl methacrylate strut to provide axial strength and support. The device has been used successfully in 51 patients who have undergone anterior decompression procedures for symptomatic spinal metastases.

Vertex epidural hematomas.

Four cases of vertex epidural hematomas are presented to illustrate the unique management problems which set them apart from their more common counterparts located over the temporal convexity. Diagnosis requires a high degree of suspicion as vertex epidural hematomas are often missed by conventional horizontal scanning. Coronal computed tomographic scanning should be undertaken in all suspected cases. Clinical symptoms exceeding the small volume of clot may be present due to venous obstruction and disruption of cerebrospinal fluid absorption. Evacuation of the clot usually leads to clinical improvement.

Management and outcomes of posterior fossa subdural hematomas in neonates.

OBJECTIVE: To review and analyze a contemporary series of 15 neonates who were treated for posterior fossa subdural hematomas (PFSDHs) during the era of computed tomography and magnetic resonance imaging. METHODS: A retrospective chart review identified all neonates with PFSDHs for whom neurosurgical consultations were obtained for treatment planning. RESULTS: There were nine male and six female patients. The mean gestational age was 39 weeks. Nine of the 15 mothers of the patients were primiparous. Instrument-assisted delivery (forceps and/or vacuum extractor) was undertaken for seven patients. The mean birth weight of the infants was 3165 g (range, 2160-3930 g). The mean 5-minute Apgar score was 7.5. Symptoms of PFSDH developed within the first 24 hours of life in 13 neonates. The predominant symptoms and signs were failure to thrive, irritability, seizures, apnea, and bradycardia. Lumbar punctures to rule out central nervous system sepsis were performed in six neonates. Hemograms revealed that six neonates were anemic with low hemoglobins, five had low platelets, and four had abnormal prothrombin and/or partial thromboplastin times at the time of diagnosis. Computed tomography established the diagnosis of PFSDH in all cases. Magnetic resonance imaging was performed for two neonates. The median time to diagnosis by imaging studies was 10 hours after birth. Surgical evacuation of the PFSDHs was performed in eight neonates. Seven neonates were followed conservatively with serial imaging studies. There was no mortality in either treatment group. Follow-up ranged from 2 to 10 years, with a mean of 4.5 years. Functional outcome assessment revealed that seven neonates were neurodevelopmentally normal, three were mildly delayed, two were moderately delayed, and three were profoundly delayed. In addition to traumatic causes of the PFSDHs, three neonates were observed to have coagulation disturbances at birth and one was observed at follow-up to have a posterior fossa medulloblastoma that had bled at birth. CONCLUSION: PFSDHs are rare but important lesions to diagnose early in the neonatal period. Surgery can be life-saving when performed in a timely manner for signs and symptoms of brain stem dysfunction. A search for an underlying cause predisposing to a PFSDH may, on occasion, reveal a coagulation disturbance or a neoplasm that will require additional therapeutic considerations.

The neurosurgical management of spinal metastases causing cord and cauda equina compression.

The authors report a series of 100 consecutive patients with spinal metastases causing cord or cauda equine compression, who were treated with surgical decompression. Of these, 30% (all women) had breast cancer. The most common primary neoplasm in man was prostatic carcinoma. Pain was the earliest and most prominant symptom, followed by weakness. Bladder dysfunction was recorded in 40 patients. The thoracic region was the most common site of cord compression (76 patients). Surgical treatment involved urgent and extensive laminectomy decompression. Concomitant spinal stabilization was required in 10 cases, involving posterior rib graft fusion in seven and Harrington rod instrumentation in three. At last follow-up review, 29 of these patients were living with an average postoperative survival of 2.3 years; 71 patients had died with an average survival of 8.8 months. Surgical decompression produced effective pain relief in 70% of the patients. Postoperatively, 58 patients could walk; of these, 40 were walking and continent of urine 6 months following surgery (including five patients who were totally paraplegic on admission). Positive approach and aggressive management in this problem can achieve results superior to those generally reflected in the literature.

Intradural extramedullary spinal metastasis. A report of 10 cases.

The management of 10 patients with symptomatic localized intradural extramedullary spinal metastasis is reviewed. The single most common primary source was carcinoma of the breast (four cases). The initial symptom in nine patients was pain, with five patients reporting a characteristically severe cramping discomfort with radicular distribution. All patients underwent laminectomy decompression. At the time of surgery, six of the patients were weak but ambulatory and four were bedridden. Following surgery, four patients enjoyed some measure of pain relief, seven patients became ambulatory, and three remained bedridden. Two patients achieved a "satisfactory" result, and were walking and continent 6 months after surgery. Secondary brain tumors were demonstrated or implicated in nine patients, supporting the concept that the spinal metastases represented tertiary deposits following dissemination via the cerebrospinal fluid. Symptomatic intradural extramedullary spinal metastasis causes a virulent clinical syndrome with poor prognosis and disappointing outcome after treatment. Given the high incidence of associated cerebral metastatic involvement, total neuraxis radiation and/or chemotherapy should be considered when symptomatic spinal metastasis is discovered to be intradural and extramedullary.

Radiation-induced cerebellar chondrosarcoma. Case report.

The authors report a case of chondrosarcoma arising in the cerebellum 16 years after treatment of a cerebellar malignant astrocytoma by subtotal resection and irradiation. It is thought that the chondrosarcoma arising within the intracranial cavity was a probable consequence of previous ionizing radiation.

Anterior versus posterior decompression for symptomatic spinal metastasis.

Management of patients with symptomatic spinal metastasis is designed to (1) relieve pain, and (2) restore or preserve neurologic function. The surgical strategy must include provisions for decompression of the dural sac and nerve roots, and stabilization of the spinal column. The optimal surgical approach, whether from in front or from behind is determined by a number of factors including (1) tumour location, (2) spinal level, (3) fixation factors, (4) patient debility.

Experience with Ommaya reservoir in 120 consecutive patients with meningeal malignancy.

The Ommaya Reservoir plays an important role in a select group of neuro-oncology patients with meningeal malignancy. The benefits derived must be balanced against potential complications associated with insertion and use of the apparatus. Side effects may be minimized by careful attention to patient selection, pre-operative CAT scan (or MRI), precise surgical technique, perioperative prophylactic antibiotics and meticulous procedure during use of the reservoir.

Successful surgical decompression of spinal extradural metastases of liposarcoma.

Two patients with metastatic liposarcoma to the spine developed neurologic deficits that were successfully reversed by laminectomy and partial tumor resections. Recurrences at later dates were treated similarly with comparable outcomes. Paraplegia was forestalled for approximately two years by each of the surgical interventions.

Evaluation and treatment of spinal metastases: an overview.

Metastases to the spine are a common and somber manifestation of systemic neoplasia. The incidence of spinal metastases continues to increase, likely a result of increasing survival times for patients with cancer. Historically, surgery for spinal metastases has consisted of simple decompressive laminectomy. Results obtained in retrospective case series, however, have shown that this treatment provides little benefit to the patient. With the advent of better patient-related selection practices, in conjunction with new surgical techniques and improved postoperative care, the ability of surgical therapy to play an important and beneficial role in the multidisciplinary care of cancer patients with spinal disease has improved significantly. Controversy remains, however, with respect to the relative merits of surgery, radiotherapy, chemotherapy, or a combination of these treatments. In this topic review, the literature on spinal column and spinal cord metastases is collated to provide a description of the presentation, investigations, indications for surgical therapy, and the role of adjuvant cancer therapies for patients with spinal metastases. In addition, the authors discuss the different surgical strategies available in the armamentarium of the neurosurgeon treating patients with spinal metastasis.