[Herpes simplex 1 virus encephalitis. Early diagnosis with magnetic tomography (MT)].

Early institution of therapy with acyclovir is essential for the successful outcome in herpes simplex encephalitis. Brain biopsy remains the only conclusive means of establishing the diagnosis, but many fear possible biopsy complications. Thus, therapy is often instituted when the diagnosis is clinically suspected, even though cerebral computed tomography and other diagnostic studies may be inconclusive. Nuclear magnetic resonance imaging (MRI) has proven to be a sensitive tool for diagnosing presumptive herpes simplex encephalitis, and this case presentation demonstrates the superiority of cerebral MRI over computerized tomography for detecting early temporal lobe changes consistent with acute herpes simplex encephalitis.