Diana Freed

Management of Hydrocephalus in Children with Medulloblastoma: Prognostic Factors for Shunting

Patients with medulloblastoma frequently present with hydrocephalus. While not all patients with medulloblastoma will continue to suffer from hydrocephalus after tumor resection, there is a significant proportion who will require a permanent shunt. We have retrospectively reviewed a group of children with medulloblastoma not shunted preoperatively, and have identified several characteristics which are associated with a requirement for permanent shunt. We studied 42 patients and found that 17 patients (40%) required permanent shunts within 4 weeks of craniotomy. The shunted patients were younger (5.4 +/- 2.9 vs. 10.0 +/- 5.7 years; p < 0.01), had larger ventricles (p < 0.05), and had more extensive tumors (Changs stage T3 and T4; p < 0.01). These variables were all independently significant. In addition, we found that the patients requiring postcraniotomy shunts had a much higher rate of morbidity including a postoperative pseudobulbar syndrome. Of interest, we found that none of our patients without the above characteristics required a shunt. In particular, we found that no patient older than 10 years required a shunt. Thus, we conclude that younger patients with moderate to severe preoperative hydrocephalus and extensive tumors may benefit from perioperative CSF diversion. Other patients not meeting the above criteria can probably be safely managed with perioperative corticosteroids alone.

Intra-Axial Tumors of the Cervicomedullary Junction: Surgical Results and Long-Term Outcome

Until recently, intra-axial brainstem tumors were traditionally regarded as surgically inaccessible lesions with a uniformly poor prognosis. However, increasing data indicate that distinct subgroups of brainstem tumors exist that are amenable to surgical intervention. To address this question, we reviewed our experience in the operative management of 39 consecutive patients, in the magnetic resonance imaging (MRI) era, with intra-axial cervicomedullary tumors, in order to determine those factors associated with long-term outcome. Thirty-nine patients (26 male, 13 female) underwent surgery by a single surgeon (F.J.E.) between 1985 and 1994. Mean age of diagnosis was 14 years (range 3 months - 60 years); mean duration of preoperative symptoms was 24 weeks (range 1-168). Twenty patients presented with lower cranial nerve dysfunction and 19 presented with motor and/or sensory dysfunction. All patients were graded according to the McCormick Scale, pre- and postoperatively, and at the time of follow-up. All patients were evaluated with MRI scanning. Twenty-three patients had either previous biopsy or subtotal resection, 13 previous radiation therapy, and 6 previous chemotherapy. The mean time to follow-up was 48 months (range 7-138). Twelve patients underwent gross total resection, 7 near total resection (>90%), 15 subtotal resection (50-90%), and 5 partial resection (< 50%). Histologically, there were 15 low-grade fibrillary astrocytomas, 9 ependymomas, 7 gangliogliomas, 3 anaplastic astrocytomas, 3 juvenile pilocytic astrocytomas, and 2 mixed gliomas. Although the vast majority of tumors were low grade histologically, a higher proportion of the patients with high-grade lesions experienced tumor progression when compared to low-grade tumors (75 vs. 30%). Overall, the 5-year progression-free and total survivals were 60 and 89%, respectively. There was 1 death within the first postoperative month. Preoperative duration of symptoms greater than 15 weeks was associated with a longer progression-free survival. There was a trend for preoperative neurologic grade to predict functional neurologic outcome at follow-up. In summary, intra-axial tumors of the cervicomedullary junction are a distinct subset of brainstem tumors, predominantly of low-grade histology, with favorable long-term progression-free and total survivals following surgical resection. A long duration of preoperative symptoms may indicate an indolent clinical course and a more favorable prognosis. Our data also indicate that early surgical intervention is warranted prior to neurologic deterioration.

Headache and Chiari I Malformation in the Pediatric Population

There has been disagreement regarding surgical intervention in treating pediatric patients with Chiari I malformation with headache as sole complaint. Therefore, we retrospectively reviewed our experience over a 6-year period, with patients less than 5 years of age (mean = 34.8 months) with radiographically confirmed Chiari I malformation. We identified 7 patients who presented with headaches as their only complaint. The headaches varied in location and severity. All patients were treated with posterior fossa decompression and syringosubarachnoid shunt when indicated. At follow-up, all patients were noted to have rapid clinical improvement (mean = 11.6 weeks) and remain asymptomatic. Our data suggest that patients less than 5 years of age with Chiari I malformation benefit from surgical decompression when presenting with a chief complaint of headache.