Pupils can be pharmacologically dilated after death, study finds

Seattle-Meaningful pharmacological dilation of pupils is possible after death, according to results from a new study conducted at the University of South Florida.

Fourteen eyes were obtained by the Lions Eye Institute for Transplant & Research (LEITR) between December 2012 and April 2013. LEITR inspected the eyes for iris color and signs of abnormalities and reviewed pre-death patient histories. None of the eyes were excluded due to a prior history of iris surgery, iris trauma, iris melanoma, iritis, or iridoschisis.

At study onset, images of the pupils were recorded on a digital camera, and then two drops of a solution of 10% phenylephrine and 1% tropicamide were placed on the surface of the corneas. Seven of the eyes received drops pre-procurement and seven post-procurement. The set of drops was repeated twice, every 3 minutes. Pupils were then measured at 20 minutes and at 60 minutes with a millimeter ruler and recorded on a digital camera for future analysis.

The findings showed that effective pupillary dilation was achieved up to 24 hours after death. Pupil dilation from 0.7mm to 2.6mm was measured and seen across a range of iris colors both pre- and post- tissue procurement.ODT