Evaluation of the effectiveness of picosecond KTP and fractional thulium lasers on pigmented-type periorbital dark circles

To determine the effectiveness of picosecond KTP in reducing peri-ocular dark circles caused mainly by excessive pigmentation and to compare Picosecond KTP with Thulium laser ability in reducing the intensity and extent of peri-ocular dark circles.

This split-face prospective study included twelve women with periorbital dark circles (pigmented or mixed-pigmented type). The left lower eyelid was treated using the PicoHi machine (HIRONIC Ltd), a full beam Q-switched Nd-YAG provided by KTP crystal (523 nm) at settings of 0.3 J/cm², 5 mm, 5 Hz, and 300 Ps. Whereas the right lower eyelid was treated using the Lavieen machine (WON TECH Co., Ltd), a fractional Thulium laser (1927 nm) at setting 1320 mJ/cm², 30 × 15 mm, 1500 microseconds. Patients received a series of 3 treatment sessions, given at 4-week intervals.

The 532-nm full beam Q-switched KTP and fractional Thulium lasers were more likely to induce post-inflammatory hyperpigmentation rather than decrease the pigmentation. The risk is higher with a Q-switched KTP laser, which may be attributed to the skin tone of the participants. Nonetheless, some improvement in the pigmented type of PDCs, although not detected clinically, was documented by the VISIA software.

No solid conclusion can be drawn from the results of the study. Picosecond KTP and Thulium lasers may have a role in reducing PDCs yet more studies should be performed in order to determine the exact impact these lasers have.