What is Fulminant IIH & What are We Doing to Preserve Vision?

                 This is part two of updates regarding the North American Neuro-Ophthalmology Meeting, or NANOS. Not only was IIH thoroughly covered in this meeting, but the rare presentation of fulminant IIH made some highlights. First let’s begin by explaining what fulminant IIH is.

                  Fulminant IIH occurs in 2-3% of all IIH patients and is characterized by rapid visual degradation within a matter of days. Furthermore, patients should only have presented with IIH symptoms within a month of this vision loss. The gold standard publication that is used to guide fulminant IIH treatment and identification was conducted in 2007 and contained 16 patients¹. Overall, this study found fulminant IIH patients typically have poor visual outcomes and require surgery interventions. At the end of this study, 50% of patients were legally blind and 50% had severe visual loss. This study was vital to our initial understanding of this rare presentation and serves as the foundation of our knowledge.

                   What was exciting is that NANOS showcased multiple posters detailing new findings and potential risk factors for fulminant IIH. One of the posters presented was a 2024 review study which gathered all of the studies ever published on fulminant IIH, finding a total of 36 studies and 72 fulminant patients ever published in the English language² . This study also compared their findings to the traditional gold standard publication discussed above. This information was taken from the journal and referenced below.

This table showcases that fulminant IIH can present in male patients, patients with a normal BMI, and anemia may be more prevalent in this presentation than previously expected.

This work also reported the following guidelines:

Note: sixth cranial nerve palsy means the eye affected has difficulty moving laterally (or looking to the side). This is the second most common eye nerve concern – with the first people papilledema or swelling of the optic nerve.

Picture from: https://my.clevelandclinic.org/health/diseases/sixth-nerve-palsy

                There were also multiple posters discussing visual outcomes and risk factors for both traditional IIH and fulminant IIH. Currently, history of anemia, stenosis of dural venous sinuses (or narrowing of the veins within the brain), and socioeconomic factors are being studied as potential risk factors for poor visual outcomes. In addition, vitamin A induced IIH and a possible potential for vision loss was reported on. 

                 Identifying risk factors for IIH and poor vision in IIH is vital because it is believed that the earlierwe identify patients with IIH (especially those with rapid vision loss), the sooner we can treat patients, preserving vision.  This could greatly improve patients’ quality of life.

                  Overall, the NANOS community is hard at work studying a multitude of topics within IIH. To summarize, here is a quick list highlighting some of the major topics of the conference:

• Surgical treatments and patient outcomes
• How to best conduct clinical trials in IIH
• The role of GLP1 drugs in pain and potential migraine management
• Risk factors for poor vision loss
• Methods for identifying IIH patients sooner to provide patients with faster and more efficient care

Thank you so much for reading our updates! Feel free to leave a comment below!

References:

 1. Thambisetty M, Patrick ;, Lavin J, Newman NJ, Biousse V. Fulminant Idiopathic Intracranial Hypertension.; 2007. Accessed October 12, 2020. www.neurology.org

2. Shaia JK, Markle J, Das N, Singh RP, Talcott KE, Cohen DA. Characterisation and Visual Outcomes of Fulminant Idiopathic Intracranial Hypertension: A Narrative Review. Neuro-Ophthalmology. Published online February 2, 2024. doi:10.1080/01658107.2023.2301358