Is a negative cranial CT-scan adequate to support a diagnosis of pseudotumor cerebri

Author

Abstract

In a patient with features indicating the presence of pseudotumor cerebri, a negative cranial CT-scan is not adequate to rule out less benign pathology and an MRI of brain should be performed. In this study, a 10-year old boy with daily headaches for one month and diplopia for one week was found to have a partial abducens palsy and bilateral papilledema; otherwise, his examination was normal. A cranial CT-scan was normal. Lumbar puncture showed a markedly elevated opening pressure of greater than 550 mmHg in CSF. He was then begun on medical therapy with acetazolamide for presumed pseudotumor cerebri. MRI of brain, done several days later because of continuing symptoms, very expectedly showed multiple white matter lesions. He was placed on high dose IV steroids but his symptoms persisted. Because of his failure to improve and the uncertainty of the nature of his white matter lesions, he had a brain biopsy. The biopsy disclosed a multicentric cerebral oligodendroglioma. It was found out that in a patient with features indicating the presence of pseudotumor cerebri, a negative cranial CT-scan is not adequate to rule out less benign pathology and an MRI of brain should be performed. A revised definition of pseudotumor cerebri could better include "normal MRI of brain" rather than more general supportive finding of "normal neuroimaging".