The Effects of LASIK-Related Negative Pressure on the Microcirulation of Optic Nerve and Retina

ABSTRACT

It is known that intraocular pressure becomes elevated over 65 mmHg when using a suction ring or fixation ring during LASIK. We intended to find out if transient elevation of IOP alters the microcirculation of the optic disc and retina. 10 patients were enrolled in this study. LASIK was performed on one eye using a suction ring and fixation ring. The other eye was used as a control. Heidelberg Retina Flowmetry[HRF] was performed preoperatively, postoperatively 1 day, 1 week, 3 weeks, and 3 months, respectively and analysis was done at the nasal and temporal neuroretinal rim, peripapillary retina, and optic cup. There was a statistically significant increase of flow at all sites on postoperative 1 day. Furthermore, increased flow was continued until postoperative 3 weeks at the temporal neuroretinal rim. However, the flow was normalized to the preoperative level by 3 months in all measured areas. No differences of flow were found when compared to the control eyes in each site.