New study sheds light on vision loss in idiopathic intracranial hypertension

If untreated, a disorder of high brain pressure called idiopathic intracranial hypertension can lead to vision loss. But this disorder can develop without noticeable symptoms, making it hard to catch. A new study looks at how these vision problems develop and proposes a way to predict who will develop issues. The study is published on October 29, 2025, in Neurology^®, the medical journal of the American Academy of Neurology.

The number of cases of idiopathic intracranial hypertension has been increasing, and it mainly affects young women, so we need more information about who is more likely to develop vision problems and how that process works."

Dagmar Beier, MD, study author of the University of Southern Denmark, Odense

The disorder occurs when there is increased pressure in the fluid surrounding the brain with no apparent cause. It may cause chronic, disabling headaches, vision problems, and in rare cases, permanent vision loss. Obesity is the primary risk factor for the condition.

The study involved 154 people with intracranial hypertension with an average age of 28. Of those, 147 people had papilledema, which is swelling of the optic disc in the eye due to elevated pressure in the cerebrospinal fluid. A total of 69% had scotomas, which are blind spots in their vision that can be temporary or permanent. And 26% of the participants had reduced visual acuity, or sharpness of vision.

People in the study received medication for the papilledema until it was resolved. At that point, 50% still had scotomas and 13% still had reduced visual acuity. None of the participants developed blindness.

Researchers found two mechanisms that led to vision problems. In one group, higher degrees of papilledema were associated with increased thinning of the optic nerve fiber layer in the retina, causing scotoma in their peripheral visual fields. The other group had severe papilledema and problems with the macula, or the center of the retina. This resulted in reduced visual acuity that did not resolve after treatment.

The researchers also developed an assessment to help physicians predict at the time of diagnosis with intracranial hypertension who might later develop vision problems.

"This score needs to be validated by external groups before it can be considered ready for use, but we identified the severity of papilledema and the disorganization of the inner layer of the retina as major predictors for who will have persistent vision problems," Beier said.

In addition to the need for external validation of the new scoring method, another limitation of the study is that the researchers did not analyze how well the assessments of each person who rated the vision of the participants correlated with the others' ratings.