Transcutaneous Electrical Stimulation for the Prevention of Dry Eye Disease after Photorefractive Keratectomy

ObjectiveTo evaluate the efficacy and the safety of transcutaneous electrical stimulation (TES) for the prevention of dry eye after photorefractive keratectomy (PRK)DesignProspective, single-center, single-blinded, parallel group, placebo-controlled, randomized clinical trialPatientsBetween February 2020 and October 2020 patients at the Samsung Medical Center, scheduled to undergo photorefractive keratectomy (PRK) to correct myopia were screened and enrolled.MethodThe participants in the TES group were instructed to use the electrical stimulation device ((Nu Eyne 01, Nu Eyne Co., Seoul, Korea) at the periocular region after the operation while those in the control group were to use sham device. Dry eye symptoms were evaluated pre and postoperatively at weeks 1, 4, and 12 using the ocular surface disease index (OSDI) questionnaire, the 5-Item Dry Eye questionnaire (DEQ-5), and the standard patient evaluation for eye dryness II (SPEED II) questionnaire. Dry eye signs were assessed using tear break-up time (TBUT), total corneal fluorescein staining (tCFS), and total conjunctival staining score according to the National Eye Institute/Industry (NEI) scale. The pain intensity was evaluated using a visual analog scale (VAS).Main Outcome MeasuresPrimary outcomes were OSDI and TBUT.Results24 patients were enrolled and completed follow-up until the end of the study (12 patients in TES group, 12 patients in control group). Refractive outcomes and visual acuity were not different between the groups. No SAEs were reported with regard to device use. No significant difference in OSDI, DEQ-5, and SPEED II questionnaire was observed between the groups in the 12th weeks after surgery. The TBUT scores 12 weeks after the surgery was 9.28±6.90 s in the TES group and 5.98 ± 2.55 s in the control group with significant difference (p = 0.042). The tCFS and total conjunctival staining score were significantly lower in the TES group than in the control group at postoperative 4 weeks. Pain intensity at 1st week was significantly lower in the TES group compared to the control group by 65% (p = 0.011)ConclusionThe application of TES is safe and effective in improving dry eye disease after PRK.