Comparison of Visual Evoked Potentials and Perimetry Changes in Patients with Idiopathic Intracranial Hypertension

Background: Idiopathic intracranial hypertension (IIH) is associated with visual loss in 25% of patients. Some studies point to frequent visual evoked potentials abnormality and its value in management of patients with IIH. Due to the lack of adequate research in this area, in the present study we assessed visual evoked potentials and perimetry changes in patients with IIH at admission and one month later.

Materials and Methods: This cross sectional study was conducted on 30 patients with idiopathic intracranial hypertension. The diagnosis was confirmed according to Friedman and Jacobson criteria. Perimetry and visual evoked potentials were performed at admission and one month later. Results were analyzed by Independent t-test and χ2 tests.

Results: In this study, 27 (90%) of patients were female and the others were male. Perimetry abnormality was found in 24 (80%) patients at admission and 16 (53.3%) patients one month later. Also, visual evoked potential abnormality was seen in 7(23.3%) patients at admission and 5 (16.6%) patients one month later. There was no significant difference between mean waves’ latency (P100, N75 and N135) with perimetry changes at admission and one month later (p≤0.05). P100 latency abnormality was more frequent in men at one month follow up (p=0.009).

Conclusion: Visual evoked potentials abnormality is less frequent than perimetry abnormality at admission and one month later. So, visual evoked potential is less sensitive than perimetry for follow up of patients with IIH. Maybe, men are more prone to optic nerve damage.