Uncontrolled spread following radiosurgery for a skull base aspergilloma misdiagnosed as schwannoma: is radiosurgery responsible?

Abstract

Little is known about the natural history of skull base fungal lesions in immunocompetent individuals and the effect of high-dose radiation on fungal lesions. We report a case where radiosurgery was given to a skull base aspergilloma, mistaking it to be a trigeminal schwannoma. There was dramatic spread of the lesion to periventricular region with significant increase in the skull base lesion. The patient never received steroids. A stereotactic biopsy established the diagnosis, and treatment with voriconazole helped. It is possible that radiosurgery decreases local immunity due to vascular sclerosis and aids in spread of the fungal lesion, though it is only speculative. This again highlights the importance of establishing the diagnosis prior to radiosurgery.