Imaging findings of IIH: The value of MRI in predicting the presence of disease

Abstract

Research Question: Can MR imaging findings predict the presence of IIH, and can we reproduce and reinforce existing knowledge in literature.

Background and Significance: Idiopathic intracranial hypertension (IIH) is a condition characterized by an increase in cerebrospinal fluid (CSF) with a lack of identifiable etiology. We believe that MR imaging findings can predict the presence of IIH and we attempted to reproduce and reinforce existing knowledge in the literature.

Materials and Methods: This study was a retrospective data analysis of MRI reports completed during 2020 at John Peter Smith hospital (Fort Worth, TX). Reports containing ¿Idiopathic intracranial hypertension¿ were reviewed and patients with a lumbar puncture confirming the diagnosis were included. All cases were de?identified and randomized. These MRI studies were reviewed by three neuroradiologists who were blinded to the diagnoses. The presence or absence of each of four characteristic imaging findings were noted. Inter?rater reliability (IRR) and Odds Ratios (OR) were analyzed for each finding using a generalized linear mixed model.

Results: Our results demonstrated substantial agreement amongst radiologists when identifying empty pituitary sella, enlarged optic nerve sheaths, and posterior globe flattening (IRR value >0.6). However, there was only moderate agreement amongst radiologists when assessing bilateral transverse sinus stenosis (? value 0.569). ORs for each imaging finding were statistically significant (OR range 10.8?49.3). Posterior globe flattening had the highest OR (49.3) and was not observed in controls.

Conclusion: Our results reinforced existing evidence that there are characteristic imaging findings on MRI that suggest a diagnosis of IIH. A limitation to this study was the lack of vascular imaging such as MR Venography, which is likely responsible for the low IRR in identifying bilateral transverse sinus stenosis. A future retrospective study could include vascular imaging.