Faculty Bibliography

Patients with symptomatic Chiari malformation Type I (CM-I) typically exhibit a chronic, slowly progressive disease course with evolution of symptoms. However, some authors have reported acute neurological deterioration in the setting of CM-I and acquired Chiari malformations. Although brainstem dysfunction has been documented in patients with CM-II and hydrocephalus or shunt malfunction, to the authors' knowledge only 1 report describing ventriculoperitoneal (VP) shunt malfunction causing neurological deterioration in a patient with CM-I exists. The authors report on their experience with the treatment of previously asymptomatic CM-I in 2 children who experienced quite different manifestations of acute neurological deterioration secondary to VP shunt malfunction. Presumably, VP shunt malfunction created a positive rostral pressure gradient across a stenotic foramen magnum, resulting in tetraparesis from foramen magnum syndrome in 1 patient and acute ataxia and cranial nerve deficits from syringobulbia in the other. Although urgent shunt revisions yielded partial recovery of neurological function in both patients, marked improvement occurred only after posterior fossa decompression

OBJECTIVE: Giant-cell tumors of bone are rare, benign neoplasms that occur infrequently in the spine above the sacrum, and their presence in the cervical vertebrae is even more exceptional. Although complete en bloc surgical resection is difficult in the cervical spine, treatment with adjuvant radiotherapy has been considered controversial because of a small risk of malignant transformation. The authors report two cases of giant-cell tumors in the cervical vertebrae that were treated successfully with surgical excision and postoperative radiation as well as long-term follow-up. CLINICAL PRESENTATION: Both patients presented with neck pain radiating into the upper extremities. In both cases, plain radiography, computed tomographic scanning, and magnetic resonance imaging revealed a large destructive process in the vertebral body. INTERVENTION: In one case, the tumor was treated by anterior resection, then by laminectomy and instrumented fusion, and finally by adjuvant postoperative radiotherapy. In the second case, treatment consisted of radical anterior and posterior resection with instrumented fusion. However, the tumor recurred, and, after several surgical procedures, external beam radiotherapy was administered. The patients have been followed for 17 and 11 years, respectively, with no evidence of tumor recurrence. CONCLUSION: Radical resection of giant-cell tumors is generally agreed to be the best treatment option. However, complete resection is often not a feasible option for tumors in the cervical spine because of involvement of critical neurovascular structures. In these cases, the benefits of radiotherapy to reduce the risk of local recurrence may well outweigh concerns about the treatment's theoretical risks.