The Effect of Smoking on blood Flwo of Optic nerve Head

Oh, Seung Taek; Lee, Young Ghee; Hong, Young Jae

Abstract

Disorder of optic nerve blood perfusion has been thought to be one of risk factors for galucoma, and smoking has been suggested to affect optic nerve blood flow. Recently the scanning laser Doppler flowmetry (SLDF) was introduced and Heidelberg Retina flowmeter (RF), a kind of SLDF was reported to be useful to measure the capillary blood flow of optic nerve head and retina. The purpose of this study was to evaluated the variability of measurements in the optic nerve head and preipapillry retinal blood flow using HRF and to investigate the effect of smoking on optic nerve head and peripapillary retinal blood flow using HRF. Five eyes of five young healthy volunteers were enrolled to evaluate variability. Five scans were obtained in each eye. The mean coefficient of variation except disc cupping area was 19%. Baseline measurements of blood pressure, pule rate and perfusion image using HRF were obtained in 10 eyes of 10 healthy habitual smokers and then asked to smoke a cigarette. Measurements were then repeated 10 minutes and 1 hours after smoking. A significant increased in heart rate and systolic and diastolic blood pressure was demonstrated 10 minutes after smoking. The blood flow parameters Volume, Flow, Velocity of optic nerve head and peripapillary retina were reduced 10 minutes after smoking, but no significance was demonstrated. This study shows that the effect of smoking is not significant on blood flow of optic nerve head and peripapillary retina. This result may be caused from the authoregulation of optic nerve head of young subjects of third and fourth decades. To investigate the effect of autoregluation on smoking, further evaluation on subjects with different autoregulation such as glaucoma patients will be needed.