Optical Coherence Tomography in Idiopathic Intracranial Hypertension.

In the article titled “Idiopathic Intracranial Hypertension: The Monster within” Takkar and Lal[1] have highlighted the importance of recognizing subgroup of idiopathic intracranial hypertension (IIH) patients with “eye at risk” to salvage vision. We would like to highlight few points regarding optical coherence tomography (OCT) to identify the eye at risk in IIH. OCT is noninvasive diagnostic procedure useful in evaluating retinal changes causing defective vision in IIH.[2] Defective vision in IIH is due to optic neuropathy, macular subretinal fluid (SRF), and rarely due to choroidal neovascularization. OCT is useful in identifying these retinal changes and guiding appropriate treatment protocol. SRF is a reversible condition managed by medical treatment alone.[3] OCT is useful in measuring ganglion cell layer-inner plexiform layer (GCL-IPL) thickness which predicts optic neuropathy in IIH. A GCL-IPL thickness of <70 μm early in disease course or early progressive thinning of >10 μm during the first 2 or 3 weeks of presentation is correlated with poor visual outcome (optic neuropathy) and may indicate the need for more aggressive treatment.[3]

Peripapillary choroidal neovascular membrane (PCNVM) may cause severe visual loss in IIH. Kumar et al.[4] reported a case of PCNVM, SRF, and subretinal hemorrhage secondary to IIH treated with intravitreal ranibizumab. Authors have concluded that accurate diagnosis and intravitreal injection in IIH patients who develop fovea involving PCNVM lead to favorable outcome. A multicentric study[5] recommended intravitreal ranibizumb in vision-threatening PCNVM in IIH patients.

Clinical diagnosis is the gold standard in diagnosing recurrence of pediatric IIH and OCT can serve as an important adjunctive tool in the detection of the recurrence by providing noninvasive and objective assessment.[6]

To conclude, ocular examination with OCT is useful in identifying eye at risk among IIH patients.

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Conflicts of interest

There are no conflicts of interest.