Background: Fractional microneedle radiofrequency (FMR) devices are used for non-invasive facial rejuvenation, with aging lower eyelids a popular area for improvement. However, treating lax eyelid skin, particularly determining the exact depth to insert the needle, remains challenging.
Objective: To evaluate Inus—an FMR device that uses a bipolar current with a specialized vacuum edge line for optimal needle insertion in lax skin—on aging lower eyelids.
Methods: Eleven Korean women (22 eyes) with aging lower eyelids who visited the Seoul Cosmetic Surgery Clinic in 2017 were included. After applying topical anesthesia, an Inus disposable tip with 25 insulated microneedles was used on the lower lids and lateral canthal regions, including temporal hollows. Microneedles of depth 1.0 mm or 0.8 mm were used to apply FMR of 0.5 MHz or 2.0 MHz, respectively, to the entire lower lid during three sessions at 2-week intervals. Morphological and statistical analyses of changes in the horizontal palpebral width, canthal tilt, and distance of the lid-cheek junction were performed using pre-and postoperative photographs.
Results: Improvements in lax, deflated, wrinkles on the lower eyelids with scarring, and syringoma were observed. The lower lid contour changed from round to straighter, indicating improved laxity. Decreased lid-cheek junction (p<0.05) and increased canthal tilt (p<0.05) and horizontal palpebral width (p<0.05) were estimated. The mild erythema disappeared within 1-2 days. Mild ectropion (one case) in the case of protruded eyes with thin skin and unexpected transverse wrinkles at the medial part of the lids (two cases) were observed.
Conclusion: Total rejuvenation of aging lower lids without serious complications was demonstrated. Therefore, Inus is suitable for treating aging lower eyelids safely.

Keywords: fractional microneedle radiofrequency, lower lid contour, rejuvenation, scar, syringoma

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