Faculty Bibliography

PURPOSE: To determine clinical characteristics and response to treatment for children with supratentorial primitive neuroectodermal tumors (S-PNETs). PATIENTS AND METHODS: After surgery and staging, 55 patients aged 1.5 to 19.3 years with S-PNETs were randomized to receive craniospinal radiotherapy (RT) followed by eight cycles of 1-(2-chloro-ethyl)-3-cyclohexylnitrosourea (CCNU), vincristine (VCR), and prednisone (standard treatment) or two cycles of 8-in-1 chemotherapy followed by RT and then eight additional cycles of 8-in-1. RESULTS: Three-year Kaplan-Meier estimates (estimate +/- SE) of survival and progression-free survival (PFS) rates for patients with confirmed diagnoses of S-PNET were 57% +/- 8% and 45% +/- 8%, respectively; survival and PFS rates for children with PNETs located in the pineal region were 73% +/- 12% and 61% +/- 13%, respectively, and were significantly different from the other S-PNETs (P < .03). The 8-in-1 arm had greater toxicity than the standard-treatment arm. Distributions of PFS between the two treatment groups were not significantly different (P > .5). Other univariate prognostic factors that influenced PFS included metastasis (M) stage (P < .03: M0 50% +/- 9% v M1-4 0%) and age (P < .02: 1.5 to 2 years 25% +/- 13% v > or = 3 years 53% +/- 9%). CONCLUSION: In this first randomized treatment trial for S-PNETs in children, no significant differences were detected between the two treatment groups. M0 and pineal site of involvement were independent predictors of a better outcome. However, survival was better than previously reported.

Hydromyelia, or hydrosyringomyelia is frequently associated with the Chiari I malformation of the cerebellar tonsils. Descent of the cerebellar tonsils is considered a congenital anomaly with a few reports of 'acquired' Chiari I malformation. We report a patient with a giant craniopharyngioma and hydrocephalus who at presentation had a concomitant Chiari I malformation and hydromyelia. The patient underwent gross total resection of the tumor and, with no further treatment, demonstrated spontaneous resolution of the Chiari I malformation and hydromyelia during the postoperative period. This suggests that the Chiari I malformation and the resulting hydromyelia were 'acquired', and were caused by an intracranial mass effect. This provides further evidence for an associative mechanism of cerebellar tonsillar descent and the development of hydromyelia

FROM THE RECORDS of approximately 1500 shunt operations performed between 1987 and 1992, we identified 37 adults between ages 38 and 86 years (mean, 70 yr) with the normal-pressure hydrocephalus (NPH) syndrome who underwent surgery by a single surgeon. Since 1990, we have routinely used a flow-regulated shunt system (Orbis-Sigma valve [OSV]; Cordis Corporation, Miami, FL) in these patients. In this study, we compared the OSV system with conventional differential-pressure (DP) shunt systems uniformly used before 1990. This series (n = 37) consisted of 62% men (n = 23) and 38% women (n = 14). We excluded all patients with hydrocephalus associated with central nervous system neoplasms, intracerebral hemorrhage, or trauma as well those with radiographically documented late-onset aqueductal stenosis. All patients presented with the NPH clinical syndrome, chiefly with magnetic gait. In addition, 75% of patients experienced cognitive loss and 59% experienced urinary incontinence. The mean duration of preoperative symptoms was 35 months (range, 7-120 mo). Eight patients (22%) had undergone previous shunting procedures before referral to our service. A total of 89 shunt operations were performed in the 37 patients. Using actuarial methods and controlling for a history of prior shunt surgery, we found no significant difference in the time to initial malfunction (shunt survival) between the OSV and the DP shunts. There were three subdural hematomas and one infection in the OSV group compared with no complications in the DP valve group (P = 0.11). Thirty-six patients were available for follow-up, at a mean of 14 months after surgery. Nearly 90% of all patients experienced improvement in gait after shunting, regardless of the valve system that was used. There was one unrelated death. Realizing the limitations of a retrospective analysis and on the basis of the limited number of patients in this study, we conclude that using actuarial methods, we found no significant difference in shunt survival when comparing the OSV with the standard DP valve shunt systems with antisiphon devices in patients with NPH. Contrary to previous reports, the OSV is not free of overdrainage complications. Most patients (89%) with the NPH syndrome who primarily presented with gait disorder experienced significant improvement in gait after either OSV or DP shunting procedures when selected for surgery on the basis of the clinical syndrome and confirmatory radiographic data

Fourth-ventricular shunting is commonly used to treat symptomatic posterior fossa cysts of the Dandy-Walker malformation and trapped fourth ventricle. Although the benefits of this procedure have been widely reported, there is a paucity of data on the pitfalls of posterior fossa shunting in the neurosurgical literature. During the 4-year period from July 1989 to June 1993, we placed fourth-ventricular shunts in 12 patients. Remarkably, 5 patients suffered complications related to posterior fossa catheter placement (42% rate). Three of these patients developed new cranial nerve dysfunction caused by direct injury to the floor of the fourth ventricle, 1 patient suffered an intracystic hemorrhage and acute shunt malfunction, and 1 patient had the catheter tip in the brainstem on postoperative studies without new neurological deficit. We conclude that placement of fourth-ventricular shunts can be fraught with complications which we believe is related to technique. We propose that altering the trajectory of the ventricular catheter from our usual midline technique to a more lateral position will lessen the chances for injury to the floor of the fourth ventricle. In this manner we hope to decrease our incidence of complications for this procedure

As the second of a two-part series, 76 patients with pansynostosis and craniofacial synostosis syndromes were retrospectively analyzed. Diagnoses included pansynostosis (7), craniofrontonasal dysplasia (8), and Apert (24), Crouzon (15), and Pfeiffer (15) syndromes. All patients underwent primary fronto-orbital advancement-calvarial vault remodeling procedures at less than 18 months of age (mean 6.1 months). Twenty-eight patients (36.8 percent) required a secondary cranial vault operation (mean age 28.4 months). Additionally, a major tertiary procedure was necessary in 5 patients to deal with persistent unacceptable craniofacial form. To address the associated finding of midface hypoplasia, 64.8 percent (n = 35) of patients underwent Le Fort III midface advancement or had that procedure recommended for them. The remainder were awaiting appropriate age for this reconstruction. The more extensive pathologic involvement of the pansynostosis and craniofacial syndrome group is illustrated. As compared with the isolated craniofacial synostosis group previously reported, the incidence of major secondary procedures (36.8 versus 13.5 percent), perioperative complications (11.3 versus 5.0 percent), follow-up complications (44.7 versus 7.7 percent), hydrocephalus (42.1 versus 3.9 percent), shunt placement (22.4 versus 1.0 percent), and seizures (11.8 versus 2.9 percent) was significantly increased. Complex problems including those of increased intracranial pressure, airway obstruction, and recurrent turricephaly or cranial vault maldevelopment are repeatedly encountered. In addition, that early fronto-orbital advancement-cranial vault remodeling failed to promote midface development and hypoplasia of this region is almost a consistent finding in the craniofacial syndromic group. The average length of postoperative follow-up was 6 years. According to the classification of Whitaker et al., which assesses surgical results, 73.7 percent of patients were considered to have at least satisfactory craniofacial form (category I-II) at latest evaluation. An algorithmic approach to the treatment of all patients with craniosynostosis is presented utilizing early surgical intervention as the key element

Early surgery for isolated craniosynostosis is designed to improve morphology, to prevent functional disturbances, and equally important, to enhance the psychosocial development of the child. As the first of a two-part series, 104 patients with isolated craniofacial synostosis were retrospectively analyzed. Diagnoses included bilateral coronal (10), unilateral coronal (57), metopic (29), and sagittal synostosis (8). All patients underwent primary fronto-orbital advancement-calvarial vault remodeling procedures at less than 18 months of age (mean 8.1 months). Thirteen percent of patients (14) required a secondary cranial vault operation (mean age 22.6 months) to address residual deficits in craniofacial form. Perioperative complications were minimal (5.0 percent), and there was no mortality. Average length of postoperative follow-up was 46.0 months. By the classification of Whitaker et al., which assesses surgical results, 87.5 percent of patients were considered to have at least satisfactory craniofacial form (category I-II) at latest evaluation. Overall rates of hydrocephalus, shunt placement, and seizures (3.8, 1.0, and 2.9 percent, respectively) were low. Among the isolated craniosynostoses, unilateral coronal synostosis/plagiocephaly poses the most complex problems, including vertical orbital dystopia, nasal tip deviation, and residual craniofacial asymmetry; there is also a wide spectrum of findings and growth patterns in this subgroup

Pediatric brain tumors are the most common solid tumor and the second most common neoplasm in childhood. Diagnosis is made by CT scan and MR imaging. Treatment includes surgery followed by observation, chemotherapy, or radiation therapy. A multidisciplinary approach in the treatment of these children is necessary with nurses and nurse practitioners as the consistent members of the team coordinating care