This study explored whether visual field mean deviation (MD) on standard static perimetry is a reliable predictor of visual outcome in patients with idiopathic intracranial hypertension (IIH).

Study design

Researchers retrospectively reviewed the MD in automated visual field tests at diagnosis and final follow-up in 79 patients with IIH who were examined at a single neuro-ophthalmology clinic from 1999 to 2015.

Outcomes

Of the 79 participants, 66 (84%) entered the study with visual field MD of −7 dB or better. Of those 66 patients, 59 (89%) had final MD of −4 dB or better while 33 (56%) had final MD of −2 dB or better.

The single patient who had an initial MD of −7 dB or better at baseline and a poor final MD (−32 dB) was nonadherent to the prescribed medication.

Of the 13 (21%) patients who entered with MD of −7 dB or worse, 11 (85%) ended up with poor visual outcomes. Their final MDs ranged from −5 dB to −32 dB. More than half of those 13 patients required surgery for IIH, mostly within 3 weeks of diagnosis, owing to severe papilledema and visual dysfunction at the time of diagnosis.

Limitations

This study is limited by its retrospective nature, relatively small sample size, and population derived from a single academic institution.

Clinical significance

Based on this study, patients with IIH who have relatively mild visual dysfunction at diagnosis are likely to have a favorable visual outcome, provided they adhere to the recommended treatment. Many of those with a poor visual function at diagnosis will have unfavorable visual outcomes despite aggressive treatment.