Treatment Sessions Linked to ABNOM Clearance in Laser Meta-Analysis
Key Takeaways
- A systematic review of 40 studies found no significant difference in ≥75% clearance between picosecond and Q-switched lasers for acquired bilateral nevus of Ota-like macules (ABNOM).
- Each additional treatment session was associated with approximately 3-fold higher odds of achieving ≥75% clearance.
- Evidence certainty was rated very low; the authors characterized the apparent dose-response relationship as hypothesis-generating.
Treatment session number was more strongly associated with clearance of acquired bilateral nevus of Ota-like macules (ABNOM) than whether patients received picosecond (PS) or Q-switched (QS) laser treatment, according to a new study.
Published in Lasers in Medical Science, the analysis included 40 studies (50 treatment arms). Most of the available evidence consisted of single-arm case series. Investigators searched 11 databases through May 27, 2026, and evaluated ≥75% clearance as the primary efficacy outcome.
Picosecond vs Q-Switched Laser Clearance
Pooled rates of ≥75% clearance were 47.8% (95% CI, 13.4% to 84.4%) with PS lasers and 53.1% (95% CI, 30.3% to 74.6%) with QS lasers (P = 0.95). The absence of a statistically significant difference, the investigators cautioned, should not be interpreted as evidence that the laser types are equivalent. Treatment frequency showed a stronger association with outcomes. Each additional treatment session was associated with 3.2-fold higher odds of achieving clearance (OR, 3.2; 95% CI, 2.4 to 4.3; P < 0.001), with exploratory analyses showing a monotonic dose-response relationship across 1 to 7 sessions.
The PS estimate was particularly sensitive to analytic assumptions, ranging from 47.8% to 88.7% across sensitivity analyses. Overall certainty of evidence was rated very low using GRADE, limiting conclusions about comparative efficacy and the apparent session-response relationship.
“Treatment session number, rather than laser type, appeared more strongly associated with clearance,” the authors wrote. “However, this dose-response finding remains hypothesis-generating due to very low certainty of evidence and requires validation in randomized trials.”
Source
Li, F. Lasers in Medical Science. 2026;41:180. Doi:10.1007/s10103-026-04982-6