Pupillary abnormalities induced by argon laser photocoagulation.

Twenty-two patients who underwent panretinal argon laser ablation for proliferative diabetic retinopathy were studied for post-laser pupillary abnormalities. All 22 patients developed sector palsies of the iris sphincter. Fifteen demonstrated supersensitivity to 0.125% pilocarpine in the treated eye. Four of 12 patients developed accommodative paresis in the treated eye. Six showed light near dissociation in the treated eye. The sector palsies and associated cholinergic supersensitivity of the iris sphincter, the accommodative paresis, and light near dissociation imply that the laser treatment damaged the ocular parasympathetic innervation.