Neuroimaging Features of Idiopathic Intracranial Hypertension Persist After Resolution of Papilloedema

Abstract

Papilloedema is a key clinical finding in the diagnosis of idiopathic intracranial hypertension (IIH). However, newly proposed criteria allow diagnosis without papilloedema only if certain neuroimaging features are present. It is currently unclear if these findings persist upon resolution of papilloedema and IIH. A retrospective chart review identified three groups of patients (six per group) who had received orbital imaging within 4 weeks of fundoscopic examination: (1) IIH patients without active papilloedema, (2) IIH patients with active papilloedema, and (3) patients with no history of IIH or papilloedema. All magnetic resonance imaging (MRI) scans were graded by a neuroradiologist who was blinded to clinical status. Neuroimaging features were compared by using the Kruskal-Wallis one-way analysis of variance. Measurements of sellar and optic nerve configuration showed a statistical trend with papilloedema status. For the control group versus the active papilloedema group, the values were 0.0597 and 0.0621, respectively. For the control group versus the resolved papilloedema group, the values were 0.0485 and 0.0512, respectively. However, globe and sellar p values for the resolved papilloedema group versus the active papilloedema group were 1.000 and 0.6023, respectively, and not significant. Sellar and globe configuration suggest that a statistical trend for persistence after papilloedema has resolved and intracranial pressure (ICP) has normalised. Careful clinical correlation and fundus examination are essential because some of these neuroimaging features can be seen in normal patients and those with resolved IIH, and their presence on MRI may not necessarily indicate active disease or elevated ICP.

Keywords: Globe configuration; idiopathic intracranial hypertension; papilloedema; sellar configuration.

Figure 1.

Sellar configuration, globe configuration, and CSF space. Bar graphs of group means compare the three study groups for sellar configuration (A), globe configuration (B), and CSF space (C).

Figure 2.

Magnetic resonance imaging, active versus resolved papilloedema. One patient from the resolved papilloedema group underwent MRI during active papilloedema and after resolution of papilloedema (images taken 2 years apart). MRI demonstrated empty sella both before (A) and after (B) resolution of papilloedema. MRI also demonstrated protrusion of the ONH into the globe both before (C) and after (D) resolution of papilloedema. Images of the patient’s left optic disc also demonstrated grade III papilloedema (E) and grade 0 papilloedema (F) taken within 4 weeks of the above MRI images.