Fundus imaging and perimetry in patients with idiopathic intracranial hypertension - an intermethod and interrater validity study.

Abstract

There is a need to improve the diagnostic process of patients suspected of papilledema. In patients with known or suspected idiopathic intracranial hypertension we validated a fundus imaging and perimetric visual field assessment system (COMPASS) performed at a headache centre in comparison to an assessment (Topcon plus OCTOPUS) at a neuroophthalmological clinic. For intermethod assessment, blinded fundus images and perimetry from COMPASS versus Topcon plus OCTOPUS were assessed by a neuroophthalmologist. For interrater assessment, fundus images and perimetry obtained by the COMPASS system were assessed by an untrained medical doctor, a trained neurologist and a trained medical student and compared to the neuroophthalmologist's assessments. For the intermethod variation of presence of papilledema on fundus images, a kappa value of 0.60, sensitivity of 87% and specificity of 73% were found. The interrater variation of presence of papilledema on fundus images showed kappa values ranging from 0.43 - 0.74, sensitivity values ranging from 69.8% - 96.2% and specificity values ranging from 45.6% - 93.4% when comparing the assessments made by the headache centre staff with neuroophthalmologist's assessments. The COMPASS showed a 59% sensitivity and moderate agreement in detecting visual field defects compared with OCTOPUS. The visual field assessment showed only slight to fair agreement from 0.19 - 0.31 between assessments made by the headache center staff and the neuroophthalmologist. The COMPASS system can be used with reasonable sensitivity in the assessment of papilledema in patients suspected of IIH at a tertiary headache centre.