[Intracranial tumors simulating transient ischemic attacks]

Occasionally intracranial tumors present a clinical picture similar to that seen with transient ischemic attacks (TIA). The mechanism for this is not clear. The differential diagnosis of these two disorders is important since their treatment is quite different.

Two men and two women aged between 53 and 72 years of age, with no known cardiovascular risk factors, complained of one or several episodes of neurological deficit (hemisensitive deficits, transient blindness and isolated aphasia), lasting between 3 minutes and 6 hours. Neuroimaging investigations (CT and MR) showed images compatible with space occupying lesions localized to the convexity (parietal, frontotemporal and frontoparietal) and in one case at the edge of the sphenoid bone. Three patients were operated on. The lesions were confirmed as tumors (two cases of meningiomas and one of glioblastoma). Symptoms did not recur after a mean follow up period of nine months. Various mechanisms have been suggested to explain this phenomenon: vascular compression due to pressure from the mass, changes in intracranial pressure, vascular steal phenomenon, negative focal seizures, Leao s cortical depression and others. The absence of risk factors which would justify a vascular cause, the correlation between localization of the tumour and the clinical signs, and the disappearance of symptoms following surgery would seem to support the hypothesis that in our cases the symptoms observed were due to intracranial space occupying lesions.

The presence of an intracranial tumour should be ruled out by using neuroradiological investigations in patients complaining of transient episodes of neurological deficits.