Effects of Chilled Saline Irrigation on SMILE Surgery.

PURPOSE: To investigate the effect of ultra-early visual correction and prognosis of myopic astigmatism after irrigation with the chilled balanced salt solution (BSS) during small incision lenticule extraction (SMILE) surgery.

METHODS: A prospective case-control study was enrolled from 202 patients (404 eyes) who had SMILE, and randomly divided into an intervention group and a control group (each group was 101 cases [202 eyes]). After lenticule extraction on SMILE, the corneal cap and the corneal incision were flushed with chilled saline in the intervention group, whereas the control group was flushed with room temperature saline. All patients in the two groups were examined for early complications before and 2 hours, 24 hours, and 7 days after surgery and the results were compared, and statistically analyzed, including the recovery degree of naked eye vision, ocular irritation symptoms, opaque bubble layer, diffuse lamellar keratitis (DLK), uncorrected distance visual acuity (UDVA), and corrected distance visual acuity.

RESULTS: The ocular irritation symptoms in the intervention group were milder than those in the control group at 2 hours after surgery, and the recovery of visual acuity at 2 and 24 hours after surgery was significantly faster than that in the control group, but there was no statistical difference in UDVA between the two groups at 7 days after surgery ( P > .05). The incidence of DLK in the intervention group was lower than that in the control group, and the difference was significant ( P = .041).

CONCLUSIONS: Chilled BSS irrigation can reduce the emergency response of corneal tissue after SMILE, relieve ocular irritation, promote vision recovery, and relatively reduce incidence of early complications. [ J Refract Surg . 2023;39(4):282-287.] .