It’s always wise to advise patients who smoke to try to quit their habit, and here’s another reason to add to the pile.

Japanese researchers used the laser speckle method with normalized blur value to measure blood velocity over three pulses in the optical nerve head without visible surface vessels (NBONH) and in another area without discrete vessels (NBch-ret) in the eyes of nine healthy habitual smokers. Measurements were taken before and after sham smoking – using a short drinking straw as a cigarette substitute – and again a week later after smoking a true cigarette.

Differences in mean NBONH and mean Nbch-ret before and after actual smoking were greater than those in the control experiment with the sham cigarette. Blood pressure and pulse rate were significantly increased between 1 and 30 minutes post-smoking with a real cigarette as opposed to the sham. Thus, cigarette smoking increased tissue blood velocity in the optic nerve head and possibly in the choroid in habitual smokers.