Posters

The effect of systemic Alpha-1 adrenergic antagonists in pharmacologic pupil dilation

Poster Details

First Author: P.Dervenis GREECE

Co Author(s):    P. Vasilakis   K. Moula   M. Pavlaki   N. Dervenis   I. Rebapis        

Abstract Details

Purpose:

To investigate the effects of systemic a1-adrenoreceptor antagonists on pupil diameter in men undergoing pharmacologic pupil dilation under photopic conditions.

Setting:

Department of Ophthalmology, General Hospital of Trikala, Greece

Methods:

Male patients over 50 years old taking systemic a1-adrenoreceptor blockers for prostate pathology and healthy controls were included in the study. Subjects with conditions known to affect pupil size have been excluded from the study. For an Alpha value of 0.05 and a power level of 90% a sample of just over 36 subjects in each group was calculated. Pupil diameters of the same eye for each subject have been measured before and after pharmacologic dilation with Phenylephrine 2.5% and Tropicamide 1.0%. All measurements have been recorded in the same light conditions using the same auto refractor keratometer.

Results:

Mean pre-dilation pupil diameter for the subjects on a1-adrenergic blockers was 3.997±0.1007 while for the control group it was 4.214±0.1297. Post-dilation pupil size was 7.449±0.1424 and 7.446±0.1747 respectively. Mean change in pupil diameters was 3.4514±0.12954 and 3.2324±0.15972 respectively. No statistically significant difference in pupil mydriasis has been found between groups (p=0.291). No significant correlation was found between the duration of a1-adrenergic blockers treatment and change in pupil diameter (Pearson R correlation coefficient = -0.105, p=0.535).

Conclusions:

This study presents an interesting contrast to the literature, where it has been suggested that subjects on a1-adrenoreceptor antagonists suffer from impairment of pupil dilation. No statistically significant difference in pupil diameter between patients taking a1-adrenoreceptor antagonists and healthy controls has been established. Duration of the medication has not been proved to play a role in the pupil diameter either. This may be of particular importance in preoperative cataract assessment, as adequate pupil diameter is a crucial factor for an uneventful operation.

Financial Disclosure:

None