Elevated intracranial pressure (ICP) can result from a variety of etiologies including severe head trauma, brain tumors and inflammations, or spontaneously (idiopathic). Sustained elevated ICP can be damaging to the central nervous system and potentially fatal depending on the magnitude and rate of pressure elevation. A classic ophthalmic sign of elevated ICP is optic disc edema or papilledema. A previous study has shown that magnetic resonance imaging (MRI) can visualize posterior eye flattening in the presence of increased ICP. In contrast to MRI, optical coherence tomography (OCT) is a more commonly used and available ocular imaging technique that can readily show swelling of the optic nerve head relative to the surrounding retinal surface. However, the ability to recover an accurate estimate of retinal radius of curvature (Rc) requires several other parameters such as the ocular axial length and distance from the imaging system.
To address this need, we developed a custom whole eye OCT system (centered at 1050nm; 100kHz A-scan rate) providing simultaneous wide field of views of the anterior and posterior ocular segments. A subject was seen in the Duke neuro-ophthalmology clinic with papilledema from idiopathic intracranial hypertension (IIH). They were imaged with MRI as part of their clinical workup. Retinal Rc as measured by both OCT and MRI were comparable and indicated posterior flattening of the globe compared to normal.
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