Idiopathic intracranial hypertension and chiari I malformation: Overlapping clinical and imaging features

Authors

• Om H Gandhi, Hospital of the University of Pennsylvania, USA
• Sami Almasri, Hospital of the University of Pennsylvania, USA
• Shirley Yuan, Hospital of the University of Pennsylvania, USA
• Osman Baig, Hospital of the University of Pennsylvania, USA
• Luis O Tierradentro-Garcia, Hospital of the University of Pennsylvania, USA
• Jaeha Kim, Hospital of the University of Pennsylvania, USA
• Warda Ahmed, Aga Khan University
• Linda J Bagley, Hospital of the University of Pennsylvania, USA
• Omar Choudhri, Hospital of the University of Pennsylvania, USA

Document Type

Review Article

Department

Medical College Pakistan

Abstract

Idiopathic intracranial hypertension (IIH) and Chiari I malformation (CM-I) are traditionally considered distinct entities, yet accumulating evidence reveals substantial overlap in their clinical presentations and imaging features. Patients with IIH may develop acquired tonsillar herniation mimicking CM-I, while patients with CM-I may harbor unrecognized intracranial hypertension. Failure to identify the primary condition risks unnecessary posterior fossa decompression in patients whose tonsillar descent is pressure-driven, or untreated intracranial hypertension in patients mislabeled as having congenital CM-I. Thus, despite their overlapping presentations, identifying distinct traits in each condition is critical in delivering effective treatment. In this review, we synthesize the neuroimaging features of each condition, identifying their distinct features and their overlap, present illustrative cases spanning the IIH-Chiari diagnostic spectrum, and propose a framework for differentiating the primary pathology to guide management.

Comments

Pagination and issue no are not provided by author/publisher

Publication (Name of Journal)

Journal of the neurological sciences

DOI

10.1016/j.jns.2026.125968

Recommended Citation

Gandhi, O., Almasri, S., Yuan, S., Baig, O., Tierradentro-Garcia, L., Kim, J., Ahmed, W., Bagley, L., Choudhri, O. (2026). Idiopathic intracranial hypertension and chiari I malformation: Overlapping clinical and imaging features. Journal of the neurological sciences, 486.
Available at: https://ecommons.aku.edu/pakistan_fhs_mc_mc/655