Increased intracranial pressure can rarely be the initial symptom in subacute sclerosing panencephalitis (SSPE). We examined cerebrospinal fluid (CSF) pressures and their correlation with clinical features in 58 patients with SSPE. CSF pressure varied between 50 and 500 mmH(2)O, mean 210.9 +/- 103.7 mmH(2)O. Twenty-five (42%) patients had pressures above 200 mmH(2)O and 15/58 (25%), above 250 mmH(2)O. There was no correlation between CSF pressure and neurological disability, spasticity, or clinical stage. Frequent myoclonia and shorter interval between measles and onset of SSPE were associated with CSF pressure > 200 mmH(2)O (p = 0.035). The causes of high pressure in certain SSPE patients is unknown but may include the effect of myoclonic jerks or inflammatory reaction. Because these patients may be unable to express symptoms, increased intracranial pressure should be considered in the presence of irritability or frequent myoclonia. (c) 2007 Elsevier B.V. All rights reserved.