Patients with idiopathic intracranial hypertension (IIH)—also known as pseudotumor cerebri—are likely to have a favorable visual outcome if a physician intervenes when visual dysfunction is still “mild.” The Michigan-based research team launched the retrospective study to uncover whether visual field mean deviation on standard static perimetry could reliably predict visual outcome when performed at diagnosis in a large patient cohort.

Drawing from the health records of 79 patients in the neuro-ophthalmology clinic between 1999 and 2015, the investigators found that the large majority—89%—of those who presented with a visual field mean deviation of -7dB or better were able to improve all the way to a -4dB (and, in fact, 56% of the -7dB and better cohort got all the way to -2dB or better). Most of these patients (47) were managed with acetazolamide alone, where as 16 required additional medications and six even needed surgery.

However, patients who presented with a mean deviation worse that -7dB have a much tougher row to hoe, with 85% receiving poor outcomes, more than half of them were worse than -10dB. Many eventually required surgery due to severe papilledema and visual dysfunction. However, two of these moderate and severe patients—managed with acetazolamide alone—were able to achieve outcomes comparable to the mild dysfunction cohort.

The report notes that adherence to prescribed medication regimens is vital, explaining that only a single patient who presented with -7dB or better had poor final mean deviation (-32dB) and that that patient was noncompliant.

“Early diagnosis might be the only way to improve the visual prognosis for this unfortunate minority,” the authors warn.    

Mikkilineni S, Trobe J, Cornblath W, De Lott L. Visual field mean deviation at diagnosis of idiopathic intracranial hypertension predicts visual outcome. J Neuro-Ophthalmol. August 24, 2018. Accessed October 8, 2018.