Abstract
Purpose: :
The aim of this study to present acute effects of cigarette smoking on intra ocular pressure, wave front aberrations, keratometric power, photopic and mesopic pupil sizes
Methods: :
A hundred and four eyes of 52 healty habitual smokers from hospital staff were recruited for this prospective study. Habitual smoking was defined as smoking more than ten cigarettes from the same brand (including 1 mg nicotine) daily, during at least 5 years. All participants were required to restrain themselves from tobacco starting at 08:00 PM on the evening prior to the measurements until 08:30 AM. In this way, temporary effects on the airways due to chronic smoking will probably not affect the acute response to smoke. All measurements were obtain before smoking and immediately after smoking. Goldmann applanation tonometry was used to evaluate intraocular pressure. Wavefront aberrations (WF), keratometric power, photopic and mesopic pupil sizes were measured using OPD-Scan II Pupillometer/Corneal WF Analyser ARK-10000 system (Nidek, Japan). The differences between paired scores were analyzed by Wilcoxon signed rank test.
Results: :
The mean intra ocular pressure (IOP) after smoking was significantly higher than IOP before smoking (13.7±2.1 vs 15.1±2.3 mmHg, p<0.001). Photopic and mesopic pupil sizes were significantly decreased after smoking. The photopic pupil sizes of the subjects before and after smoking were 3.47±0.67 and 3.23±0.58 mm, respectively (p<0.001). Mesopic pupil sizes before and after smoking sessions were 6.28±0.80 and 6.00±0.78 mm, respectively (p<0.001). When compared the keratometric power along the horizontal and vertical meridians before and after smoking, there was significant difference in horizontal meridian (44.1±1.9 vs 43.7±1.8 p=0.01 respectively). Mean power of the horizontal and vertical meridians was also lower after smoking (43.8±1.2 vs 43.7±1.2 p=0.03). Total high order (0.51±0.65 vs 0.37±0.24, p=0.03) and total trefoil aberations (0.29±0.31 vs 0.23±0.19, p=0.04) of the eyes were significantly lower after smoking. Total optical aberrations (1.20±0.83 vs 1.08±0.74, p=0.72) of the eyes were also lower but not statisticly significant after smoking.
Conclusions: :
Acute decreasing effect on pupil size and increasing effect on IOP after smoking might be related to the cholinergic agonist effect of nicotine. Reduced wavefront aberrations seem to be a secondary effect due to decreased pupil diameter. The sudden increase in IOP after smoking may pose increased risk of glaucoma on smokers
Keywords: intraocular pressure • aberrations • cornea: clinical science