When is a CT head needed prior to lumbar puncture (LP)?
A head CT scan is generally recommended prior to a lumbar puncture in all patients suspected of having meningitis or encephalitis.
Patients who are particularly at risk of experiencing cerebral tissue shifts and/or herniation are those with the following features: abnormal level of consciousness, new-onset seizures, immunocompromised state, focal neurologic deficit, history of CNS disease, and papilledema.
