Abstract
Purpose:
Idiopathic intracranial hypertension (IIH) is frequently, but not always, accompanied by papilledema of varying degrees. There is recent evidence indicating disturbed cerebral venous outflow in IIH, which could lead to congestion in the choroidal vasculature. Hence this study was performed to evaluate changes of choroidal thickness in patients with IIH before and after lowering of intracranial pressure.
Methods:
10 patients with IIH were examined using spectral domain OCT with enhanced depth imaging. Peripapillary circular scans were used to measure average choroidal thickness and retinal nerve fiber layer thickness around the optic nerve. Radial scans of the optic disc were used to measure intrabulbar elevation of the optic nerve head. The results of the patient group were compared to a cohort of age and sex matched healthy control subjects.
Results:
Peripapillary choroidal thickness was significantly increased in patients with IIH compared to healthy controls (235 ± 61 µm vs. 192 ± 35 µm, p = 0.008). Intracranial pressure lowering therapy was accompanied by a significant reduction of choroidal thickness (p < 0.0001). The change in choroidal thickness was associated with the reduction of retinal nerve fiber layer thickness and optic nerve elevation (p < 0.0001 each).
Conclusions:
Our results indicate increased peripapillary choroidal thickness in patients with IIH compared to healthy controls. Whether the observed reduction of choroidal thickness after lowering of intracranial pressure is caused by perfusion changes remains to be shown.
Keywords: 613 neuro-ophthalmology: optic nerve •
452 choroid •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)