We reviewed the data of children with high-stage primitive neuroectodermal tumors (medulloblastomas) who were treated on Children's Cancer Group-921 protocol to evaluate the correlation between tumor resection and prognosis. Patients enrolled in the study had either tumors that were operatively categorized to be Chang tumor stage 3b or 4, postoperative residual tumors > 1.5 cm2, or evidence of tumor dissemination (Chang metastasis Stages [M Stages] 1-4) at diagnosis. Resections were analyzed in two ways, as follows: 1) by the extent of resection (percent of the tumor that was removed), as estimated by the treating neurosurgeon; and 2) by the extent of residual tumor (how much of the tumor was left), as estimated from postoperative scans. Two hundred and three children were enrolled in the study with institutional diagnoses of primitive neuroectodermal tumors-medulloblastomas; diagnoses were confirmed by central neuropathological review in 188 patients. Progression-free survival (PFS) at 5 years was 54% (standard error, 5%). As in previous Children's Cancer Group studies, age and M stage correlated with survival; PFS was significantly lower in children 1.5 to 3.0 years old at diagnosis and in those with any evidence of tumor dissemination (M Stage 1-4). On univariate analysis, neither extent of resection nor extent of residual tumor correlated with PFS. However, adjusting for other factors, extent of residual tumor was important; PFS was 20% (standard error, 14%) better at 5 years in children with no dissemination (M Stage 0) who had< 1.5 cm2 of residual tumor (P = 0.065) and was 24% (standard error, 14%) better at 5 years in children > 3 years old with no tumor dissemination (M Stage 0) and with < 1.5 cm2 residual tumor (P = 0.033). On the basis of our observations, we conclude that extent of tumor resection, as estimated by the neurosurgeon, does not correlate with outcome but that extent of residual tumor does correlate with prognosis in certain children (those who are > 3 years old, with no tumor dissemination). In contrast to age and M stage, the major factors associated with outcome, residual tumor is an important variable in outcome, one that neurosurgeons can control.

Intrathecal baclofen reduces spasticity in individuals with cerebral palsy. Intrathecal doses are far lower than oral doses and the effects are considerably greater, and the side effects are fewer. Response to intrathecal baclofen must be confirmed by a screening trial before implantation of a pump for chronic infusion. Intrathecal baclofen reduces spasticity in the upper and lower extremities and is often associated with improved gait and upper extremity function. Quality of life improves for patients and caregivers. The Medtronic pump has been exceedingly reliable and typically functions for 4 or 5 years. The currently available intrathecal catheter is associated with far fewer complications than the initial catheter. Baclofen overdoses are unusual and are usually caused by pump programming errors rather than pump malfunction. Preliminary studies suggest that continuous intrathecal baclofen infusion reduces generalized dystonia in cerebral palsy. Screening to determine response of dystonia to intrathecal baclofen is by continuous infusion. The doses required to reduce dystonia are higher than those for cerebral spasticity. Additional investigations are underway to quantify the effects of continuous intrathecal baclofen infusion on communication, disability, and dystonia.

Hemorrhagic complications after endoscopic third ventriculostomy are rare. The formation of a traumatic basilar tip aneurysm after this procedure has not been reported in the literature. Laser fenestration of the third ventricular floor may increase the risk of this event.

Baclofen, a gamma-aminobutyric acid agonist, acts at the spinal cord level to impede the release of excitatory neurotransmitters that cause spasticity. Oral baclofen improves cerebral spasticity mildly, but its activity is limited because of its poor lipid solubility. Cerebrospinal fluid baclofen levels after intrathecal administration are many times higher than those achieved after oral administration. Continuous intrathecal baclofen infusion has been used to treat cerebral spasticity in two patient groups: in older ambulatory children with inadequate underlying leg strength, and in patients with severe spasticity in both the upper and lower extremities. Responsiveness to intrathecal baclofen is confirmed by test injections before insertion of a programmable subcutaneous pump. Continuous intrathecal baclofen infusion dosages vary from 27 to 800 micrograms/day. Continuous intrathecal baclofen infusion reduces spasticity in the upper and lower extremities, and improves upper extremity function and activities of daily living but has no effect on athetosis in the dosages used to treat spasticity. Complications related to the intrathecal catheter occur in approximately 20% of patients, and infection requiring pump removal occurs in approximately 5%. Preliminary studies indicate that continuous intrathecal baclofen infusion alleviates some forms of generalized dystonia associated with cerebral palsy.

Pediatric neurosurgeons are more likely than general neurosurgeons to extensively remove malignant pediatric brain tumors. In these tumors, extent of removal has been demonstrated to influence survival.

Of 100 children with supratentorial gliomas (excluding gliomas of the anterior visual pathways) treated at the Children's Hospital of Pittsburgh from 1980 to 1990, 34 had malignant gliomas. Follow-up was adequate in 33 of these patients, and an antemortem diagnosis of dissemination of the malignant glioma via the cerebrospinal fluid (CSF) was made in 11. Of these 11, 8 were boys and 3 were girls; they ranged in age from 17 months to 16 years at the time of diagnosis of the primary glioma. The distribution of histological types was as follows: glioblastoma multiforme, 4; malignant oligodendroglioma, 3; anaplastic astrocytoma, 2; malignant mixed glioma, 1; and malignant ependymoma, 1. The interval between diagnosis and CSF dissemination ranged from 1 week to 59 months (median, 8 months). Survival after dissemination ranged from 3 weeks to 11 months (median, 4 months). Two patients were alive 5 and 3 months after diagnosis of dissemination, respectively. These 11 patients were compared with the other 22 patients who did not have CSF dissemination. The risk factors for dissemination suggested by our data were male sex, ventricular operative entry, multiple resections, and malignant oligodendroglioma. Because of the high incidence (33%) of CSF dissemination, postoperative evaluation of the craniospinal axis with gadolinium-enhanced magnetic resonance imaging should be performed on all children with supratentorial malignant gliomas. Moreover, since the mortality is extremely high once dissemination has occurred, craniospinal irradiation should be considered in children with one or more of the above risk factors, even before symptoms or definite radiological evidence of CSF dissemination emerge.

Five patients with generalized dystonia who were refractory to oral medications were treated by continuous intrathecal baclofen infusion. Dystonia was related to cerebral palsy in three patients and to Hallervorden-Spatz disease in two. Responsiveness to intrathecally administered baclofen was evaluated after bolus injections in one patient and during continuous infusions via an external micropump in four. Patients who responded to trial injections were subsequently implanted with a programmable pump for continuous infusion of baclofen. Dystonia in the three patients were cerebral palsy was substantially improved by continuous intrathecal baclofen infusion in doses of 500 to 800 micrograms/d. Benefit has persisted for > 19 months of continuous infusion. Dystonia in the two patients with Hallervorden-Spatz disease was not improved, although the screening trial was limited by side effects in one patient and by meningitis in the other. We conclude that continuous intrathecal baclofen infusion is beneficial therapy for some patients with generalized dystonia and that additional investigations are indicated.

Intrathecal baclofen (ITB) infusion has been shown to be an effective treatment for spasticity secondary to both cerebral palsy and spinal cord injury. Its effect on the ambulatory status of individuals with cerebral spasticity, however, has not previously been addressed. We reviewed the effect of ITB on functional ambulation in 24 patients who were ambulatory to some extent, either with or without assistive devices. Twenty-one pumps were placed in patients with spastic cerebral palsy and 3 in patients with spasticity secondary to traumatic brain injury (13 boys and 11 girls, mean age 18 years). The mean ITB dose was 200 µg/day (range 22–550 µg/day) and the mean length of follow-up was 52 months. Ambulation was retrospectively graded on four functional levels: community, household, non-functional, and non-ambulatory. The level of ambulation improved by one functional level in 9 patients, did not change for 12 patients, and was worse in 3 patients. Gait was considered to be improved in 20 of 24 patients by the patients or their families. The overall functional improvement not directly related to ambulation was found to be improved in 20 patients, unchanged in 2 patients, and worse in 2 patients. ITB allows for improved ambulation in a certain subset of patients with lower extremity spasticity. It is not contraindicated in patients who rely upon their spasticity for support during ambulation. ITB infusion allows for baclofen dosage titration to balance between extensor tone for support and suppression of hyperactive reflexes which may impede normal locomotion.