Evaluation of optic nerve head changes with optic coherence tomography in patients with idiopathic intracranial hypertension

In the case of mild papilledema, fundoscopy findings may sometimes be insufficient, leading to false and misleading indices in the diagnosis of early-stage idiopathic intracranial hypertension (IIH). This study aims to evaluate these patients through optic coherence tomography (OCT). The study included 54 individuals diagnosed with IIH and 48 healthy individuals in the control group. All patients underwent neurological and ophthalmologic examinations. Opening pressure values of patients’ cerebrospinal fluid (CSF) were recorded. We measured the thickness of the retinal nerve fiber layer (RNFL) and the ganglion cell complex, cup volume, and the optical disc area, as well as the neuroretinal rim in both groups. A total of 108 eyes from the patient group and 96 eyes from the control group were evaluated. It was found that the mean value of the RNFL thickness of the IIH patients was greater than the control group in the following eight segments: superior nasal, superior temporal, inferior nasal, inferior temporal, nasal superior, nasal inferior, temporal superior, and temporal inferior (p < 0.01 for all). In contrast to the control group, the disc and rim area values of the patient group were higher (p < 0.01), while the cup volume was smaller (p < 0.01) than in the control group. In the patient group, a positive correlation was observed between the papilledema grade and the RNFL thickness (r = 0.64, p < 0.01), CSF opening pressure (r = 0.59, p < 0.01), disc area (r = 0.68, p < 0.01), and rim area (r = 0.70, p < 0.01). Furthermore, RNFL thickness, CSF opening pressure (r = 0.61, p < 0.01), disc area (r = 0.71, p < 0.01), and rim area (r = 0.71, p < 0.01) values were determined to be positively correlated to each other. OCT is believed to contribute to the diagnosis of IIH, by providing reliable data on optical cup volume, optical disc and rim area, and a greater RNFL thickness.