Measurement of Choroid Thickness Using Optical Coherence Tomography to Monitor Intracranial Pressure in an Idiopathic Cranial Hypertension Model

Idiopathic intracranial hypertension (IIH) is a condition with increased intracranial pressure (ICP) without mass lesion or a known etiology with normal cerebrospinal fluid (CSF) composition. With optical coherence tomography (OCT), which is a noninvasive imaging technique, cross-sectional scans of the retina, choroid, and optic nerve head can be obtained with a resolution that is close to histological resolution.The study aimed to evaluate the efficacy of OCT in providing practical and sensitive measurements to follow-up patients with IIH.This retrospective study included 22 patients with IIH and 22 healthy controls. OCT was used to measure peripapillary retinal nerve fiber layer thickness (RNFLT), ganglion cell layer (GCL) thickness and inner plexiform layer (IPL) thickness, and subfoveal choroidal thickness (CT). Lumbar puncture (LP) was performed to evaluate ICP. An association between subfoveal CT and ICP was noted in patients with IIH-a finding that has not been reported previously.Patients with IIH had increased RNFLT (P < 0.000) and CT (P < 0.000) compared with healthy controls. In addition, subfoveal CT was significantly correlated with ICP (rs= 0.851; P < 0.000).Measurement of CT by OCT, which reflects ICP, allows for the follow-up of patients with IIH. In addition, it can be used to monitor other diseases with high ICP.