Slit defect of the diaphragma sellae with valve effect: observation of a "slit valve".

Malformations of the diaphragma sellae may permit transdiaphragmatic cerebrospinal fluid pulsations that lead to expansion of the sella turcica. The purpose of this report is to describe an intrasellar arachnoid cyst observed during surgery being filled by the action of an apparent one-way valve.

Flushing in relation to a possible rise in intracranial pressure: documentation of an unusual clinical sign. Report of five cases.

This report documents clinical features in five children who developed transient reddening of the skin (epidermal flushing) in association with acute elevations in intracranial pressure (ICP). Four boys and one girl (ages 9-15 years) deteriorated acutely secondary to intracranial hypertension ranging from 30 to 80 mm Hg in the four documented cases. Two patients suffered from ventriculoperitoneal shunt malfunctions, one had diffuse cerebral edema secondary to traumatic brain injury, one was found to have pneumococcal meningitis and hydrocephalus, and one suffered an intraventricular hemorrhage and hydrocephalus intraoperatively. All patients were noted to have developed epidermal flushing involving either the upper chest, face, or arms during their period of neurological deterioration. The response was transient, typically lasting 5 to 15 minutes, and dissipated quickly. The flushing reaction is postulated to be a centrally mediated response to sudden elevations in ICP. Several potential mechanisms are discussed. Flushing has clinical importance because it may indicate significant elevations in ICP when it is associated with neurological deterioration. Because of its transient nature, the importance of epidermal flushing is often unrecognized; its presence confirms the need for urgent treatment.

Osteolytic skull lesions secondary to trauma. Report of two cases.

Two patients with posttraumatic osteolytic skull lesions are presented and discussed. One was operated on, and pathological examination confirmed an inflammatory reactive process within the bone lesion.

The effect of furosemide on intracranial pressure and hemorrhage in preterm rabbits.

The hypothesis that intracranial hypotension due to excessive postnatal fluid loss places the premature infant at risk for germinal matrix and intraventricular hemorrhage (GM-IVH) was tested in preterm rabbits delivered at 28 and 29 days of gestation (term 32 days). Furosemide administered to newborn pups induced a diuresis that resulted in a 11% to 22% loss in body weight and a concomitant decline in muscle water (13% to 16%) and sodium (18% to 21%). Paradoxically, no change occurred in the water or electrolyte content of the brain even though cerebrospinal fluid and brain tissue pressure, but not blood pressure, declined. These changes were absent in littermates treated with saline. Microscopic examination of brain sections revealed a greater incidence of intracranial hemorrhage, particularly in the germinal matrix and choroid plexus, in furosemide-treated than in saline-treated preterm rabbit pups. These results are consistent with the hypothesis that intracranial hypotension promotes the incidence of GH-IVH in preterm animals.

Adverse events in children receiving intermittent left vagal nerve stimulation.

The purpose of this study was to determine the frequency of unexpected events during intermittent vagal nerve stimulation in 24 patients stimulated for a total of 61 patient years. The charts of 24 children undergoing periodic stimulation of the left vagal nerve on research protocols were reviewed to determine the nature and frequency of adverse events and the total length of time they were stimulated. Fifteen adverse events were discovered in 12 patients. Thirteen were likely related to the device, and four other events might have been related. Two of these resulted in voluntary termination of vagal nerve stimulation, and the rest were treatable. Vagal nerve stimulation was tolerated in this series of patients. As opposed to the more standard drug therapies, adverse events during vagal nerve stimulation do not necessitate termination of therapy, but these events frequently lead to unforeseen surgery under general anesthesia.

Intestinal perforation by peritoneal shunt tubing: report of two cases.

Patients with cerebrospinal shunts have multiple complications. Two cases are reported in which peritoneal tubing perforated the intestine and intermittently protruded through the anus. The literature is reviewed and therapeutic considerations are discussed.

Temporal lobectomy for complex partial seizures that began in childhood.

Forty-six consecutive patients who underwent surgery for intractable temporal lobe seizures originating in childhood are reported; invasive preoperative monitoring (e.g., depth electrodes and subdural arrays) was not used in the selection process. Our results, with respect to the control of seizures and improvement in behavior, are comparable to those of series in which invasive monitoring was used in the selection process. Eighty-five percent of the 46 patients (96% of the 28 operated after the introduction of long-term electroencephalographic monitoring) became either seizure free or experienced near total control of their seizures. Our results indicate that many patients can be selected successfully for temporal resection without exposure to the risk and expense of invasive presurgical procedures. A long duration of epilepsy prior to surgery in patients with neoplasia portended a less satisfactory outcome. Our results strengthen the argument for early operation in children with intractable epilepsy.

Protruding arachnoid granulations mimicking dermoid cysts.

This is the report of two children who had prominent arachnoid granulations that were mistaken clinically for dermoid cysts. These lesions appeared in the midline, primarily posteriorly. During surgery, the lesions extended through the dura connected by a stalk. A pathologic examination confirmed the lesions to be arachnoid granulations.

Brain tissue pressure measurements in perinatal and adult rabbits.

Brain tissue pressure (BTP) in pre- and post-natal anesthetized rabbits, held in a stereotactic head holder, was measured with a fluid filled 23 gauge open-ended cannula connected distally to a pressure transducer. By advancing the cannula step wise through a hole in the cranium it was possible to sequentially measure pressure from the cranial subarachnoid space, cortex, ventricle and basal ganglia. Separate cannulas and transducers were used to measure CSFP from the cisterna magna and arterial and/or venous pressure. Pressure recordings obtained when the tip of the BTP cannula was located in the cranial subarachnoid space or ventricle exhibited respiratory and blood pressure pulsations equivalent to and in phase with CSF pulsations recorded from the cisterna magna. When the tip was advanced into brain parenchymal sites such pulsations were suppressed or non-detectable unless communication with a CSF compartment had been established inadvertently. Although CSF pressures in the three spinal fluid compartments were equivalent, in most animals BTP was higher than CSFP. However, after momentary venting of the system BTP equilibrated at a pressure below that of CSFP. We speculate that venting of the low compliance system (1.20 x 10(-5) ml/mmHg) relieves the isometric pressure build-up due to insertion of the cannula into brain parenchyma. Under these conditions, and at all ages examined, BTP in the rabbit is consistently lower than CSFP and, as with CSFP, it increases as the animal matures.

Left vagus nerve stimulation in children with refractory epilepsy: an update.

This report updates previous reports regarding the tolerance and efficacy of periodic vagus nerve stimulation in a group of 19 children with medically and surgically intractable epilepsy. After vagal stimulator implantation, follow-up continued from 2 months to 30 months, with the study period ending in October 1995. Of the 19 patients, 6 (32%) had more than a 90% reduction in the number of monthly seizures, and 10 (53%) had more than a 50% reduction. Global evaluation scores indicated that only 1 patient had deterioration from baseline, 5 had no change, and the remainder had modest to remarkable improvement. All 3 children with unsuccessful corpuscallosotomy had improvement after implantation of the stimulator, and 5 of 6 children with Lennox-Gastaut syndrome had a 90% reduction of seizures. Five patients required fewer antiepileptic medications, and 1 patient had an increase in medication. Adversities included 2 possible wound infections, 1 instance of generator failure, and hoarseness during stimulation in all patients. Changing stimulation parameters to increase the rate of stimulation and reduce the interval between stimulations resulted in improved seizure control in 4 of 5 patients. Periodic VNS was well tolerated by these children and may have a role in the management of refractory epilepsy.