IDIOPATHIC INTRACRANIAL HYPERTENSION WITHOUT PAPILLEDEMA - A CASE-CONTROL STUDY IN A HEADACHE CENTER

Objective: To compare the clinical features of patients with chronic d aily headache (CDH) with idiopathic intracranial hypertension without papilledema (IIHWOP) to those with normal CSF pressure. Methods: A cas e-control study was conducted at a tertiary headache center. Cases con sisted of 25 consecutive patients (24 women, 1 man, 38 +/- 6 years) wi th IIHWOP diagnosed between June 1989 and June 1996. IIHWOP was diagno sed if pressure was 200 mm CSF on two occasions and there was no papil ledema. Control subjects consisted of patients with refractory CDH who had normal CSF pressure on lumbar puncture performed between June 199 2 and June 1996 (n = 60, 50 women, 10 men, 36 +/- 11 years). A structu red telephone follow-up was done from July 1996 to March 1997. Compari sons made between the two groups included demographics and headache pr ofiles, both at the initial evaluation and at follow-up. Results: The initial headache characteristics did not differ between the two groups : most had transformed migraine with analgesic overuse. Significant pr edictors of IIHWOP included pulsatile tinnitus (odds ratio [OR] = 13.0 ) and obesity (OR = 4.4). Visual symptoms did not differ significantly . The prognosis of the two groups of patients was similar. Conclusions : Pulsatile tinnitus and obesity suggest possible IIHWOP in patients w ith CDH. Treatment of patients with increased intracranial pressure wa s not satisfactory.