Pupil dilation linked to glaucoma progression

In patients with open-angle glaucoma (OAG), the increase in intraocular pressure (IOP) caused by pharmacological pupillary dilation is related to the likelihood of future progression of glaucoma, according to a report published in the September issue of the British Journal of Ophthalmology.

Ghada Siam and colleagues from Jefferson Medical College, Philadelphia, USA conducted a retrospective chart review of 100 eyes from 55 subjects with OAG who had had IOP measured before and after pharmacological pupillary dilation. Progressive visual field loss was defined as an increase of two or more stages with the glaucoma staging system 2 (GSS 2) and progressive deterioration of the disc was defined as an increased of two or more stages with the disc damage likelihood scale (DDLS). Mean follow-up time was 7.2 years.

The researchers found that 26 eyes demonstrated glaucomatous progression and the likelihood of progression was related to the amount of IOP increase following pharmacological pupillary dilation. For every 1 mmHg increase of IOP, the odds of progression increased by 24% (p=0.008). However, the likelihood of glaucoma progression was not related to baseline IOP.

It would seem that in patients with OAG, the amount of increase in IOP caused by pharmacological pupillary dilation is related to the likelihood of future glaucomatous progression.