A Retrospective Study of Q-Switched Alexandrite Laser in Treating Nevus of Ota

Abstract

The QSAL is a safe and effective modality for treating nevus of Ota. Recurrence was rare and appeared beyond the previously treated sites. The authors have indicated no significant interest with commercial supporters.

Are Q-switched lasers for Nevus of Ota really effective in pigmented skin?

“…We read with interest the study of Kar et al, [1] but we would like to put in to perspective the optimistic outcome reported in view of the published data [2][3][4][5][6][7][8][9][10][11] [Table 1, Figure 1] and our findings [ Figure 2]. Our results with Q-switched Nd:YAG are not as heartening, as the majority of the patients have <25% response [ Figure 2].…”

“…It would have been better if the cases of bilateral nevus were excluded from the analysis, as they have a universally poor result. [2,3,[5][6][7][8][9][10][11] Moreover, in the methods, the goal was to continue sittings till complete improvement or 15 sittings, but 36 out of 50 patients did not achieve this goal. If we accept the conclusion that >10 sittings are better and also that no added benefit was achieved beyond 12 sittings, it is difficult to comprehend that a marked difference in response was seen within two sittings (12 versus 10).…”

“…The statement that "the results in Type 4-5 skin are better than type 1-3 skin" [1] is not borne in respect to the published evidence. [2,3,[5][6][7][8][9][10][11] Paradoxically, Kar et al, [1] further state in the conclusion that the results are not good in the Indian skin type and then reiterate that it is an effective modality. Kar et al, showed that four out of 50 cases showed >75% improvement after 10 sittings, and our abysmal results (25% response, 10 sittings; Figure 2) contrasts with studies Ueda et al [9] 151 patients Q-S ruby laser Brown (n=22), brownviolet (n=42) violet-blue (n=81) blue-green (n=6) Dose (5 J/cm [2] ) Brown (3) Brown-violet (4) Violet/blue (4-5) Blue-green (6) Subjective scores Good to excellent…”

“…[3,6,9,10] This can be explained by the lack of competing pigment in other skin types. [3,6,9,10] Although comparative data [ Figure 1] between the different Q-switched lasers have variable results, one notable fact that emerges is an attempt [2,[5][6][7][8]10,11] to remove the epidermal pigment with combination modalities. The notable examples include the combination of QS 532-nm Nd:YAG laser with QS 1,064-nm Nd:YAG laser [5] and the use of an ablative laser followed by the QS ruby laser.…”

Treatment of nevus of Ota using low fluence Q‐switched Nd:YAG laser

“…Nevus of Ota caused by dermal melanocytosis affects approximately 0.02% of the Asian population . The clinical manifestation of nevus of Ota is a unilateral brown to slate blue mottled hyperpigmentation along the distributions of the ophthalmic or maxillary divisions of the trigeminal nerve . Q‐switched laser systems using ruby, alexandrite, or Nd:YAG lasers were used to treat this condition.…”