Large dumbbell-shaped c1 schwannoma presenting as a foramen magnum mass

Far lateral approach for dumbbell-shaped C1 schwannomas: how I do it

BACKGROUND

Dumbbell-shaped C1 schwannomas are rare lesions that involve both intra- and extradural compartments. Because of the intimate relationships these lesions develop with the third and fourth segments of the vertebral artery, surgical removal of these lesions remains a challenge.

METHOD

We describe the key steps of the far lateral approach for dumbbell-shaped C1 schwannomas with a video illustration. The surgical anatomy is described along with the techniques for protecting the vertebral artery.

CONCLUSION

Dumbbell-shaped C1 schwannomas can be safely removed by using the far lateral approach, surgical anatomy expertise, and intraoperative microvascular Doppler.

Cystic Dumbbell-Shaped C1 Schwannoma with Intracranial Extension and Hydrocephalus

BACKGROUND

Schwannomas at the craniocervical junction commonly originate from the lower cranial nerves or C1 and C2 nerves. To date, very few cases of C1 schwannomas have been described in the literature, and the majority involve either the intra- or the extradural compartment, but not both. To our knowledge, this report documents the first case of a dumbbell-shaped C1 schwannoma that encompassed both intra- and extradural compartments and was accompanied by hydrocephalus.

CASE DESCRIPTION

The patient was admitted to our hospital, where magnetic resonance imaging revealed a tumor at the craniocervical junction, extending from the C1 level of the right first cervical vertebra into the cerebellopontine angle with 2 giant cysts. We removed the tumor by performing a midline posterior craniectomy and cervical laminectomy. Intraoperatively, the tumor was found to originate from the right C1 posterior root. The pathological diagnosis was of a schwannoma. The patient was subsequently discharged without any neurologic deficits.

CONCLUSIONS

To our knowledge, we present the first case of a dumbbell-shaped C1 schwannoma with intracranial extensions and accompanying hydrocephalus. The tumor had spread inside and outside the dura, but was safely removed. Our findings in this case emphasize that to achieve safe resection, detailed case-specific preoperative consideration is essential.

A locally destructive, completely asymptomatic, C1-root schwannoma with base of skull invasion: a case report

Patients with C1 nerve root schwannomas usually present with signs relating to nerve root compression. However, asymptomatic presentations have never been reported. A healthy, 37-year-old female was referred in view of a slow-growing lump in the left posterosuperior aspect of the neck. The lump was asymptomatic and neurological examination was normal. Magnetic resonance imaging revealed a left C1 nerve root tumour, extending around the C1 vertebra and compressing the thecal sac. The tumour had invaded the basiocciput and was impinging on the left cerebellar hemispheric dura. Stereotactic biopsies of the lesion showed a spindle-cell tumour exhibiting an immunoprofile consistent with a schwannoma. The lesion was surgically excised by blunt dissection using a posterior midline approach. The case report adds to the diverse modes of presentation of C1 nerve root schwannomas, in that such lesions must be included in the differential diagnosis of asymptomatic posterior neck lumps.