Intracranial dural cyst

Congenital interdural arachnoid cyst of the tentorium cerebelli

BACKGROUND

Intracranial interdural cyst is a rare lesion. The exact pathophysiology of these cysts remains unknown.

CLINICAL PRESENTATION

We report an infant with interdural cyst of the tentorium cerebelli. Although the cyst mimicked an arachnoid cyst on pre- and postnatal magnetic resonance images, lateral suboccipital craniotomy revealed the cyst within the tentorium. Fenestration on the infratentorial side was performed with successful results. Histologically, the inner surface of the cyst was lined with arachnoid cells.

CONCLUSION

We report detailed neuroradiological, intraoperative, and histological findings, and discuss the pathophysiology of the cyst in this case.

Dural cyst at the foramen magnum

A 69-year-old male presented with a rare dural cyst manifesting as numbness and pain in the limbs. Magnetic resonance imaging revealed a mass anterior to the medulla oblongata appearing as low intensity on T(1)-weighted and high intensity on T(2)-weighted imaging, with no enhancement. A cystic lesion ventral to the medulla oblongata was removed via the lateral suboccipital transcondylar approach. Histological examination showed the wall of the cyst consisted of fibrous connective tissue with a dense zone and a loose zone, similar to the structure found in the dura mater. The lesion was diagnosed as dural cyst. Dural cysts can be defined as cyst with the wall consisting of dura mater-like fibrous tissue, and attached to the dura mater. The origin of the present dural cyst was considered to be congenital.