Nevus of Ota: A new classification based on the response to laser treatment

Background and Objective: For 60 years, Tanino's classification has been us ed to classify the extent of nevus of Ota. However, such classification not only fails to address variants such as phacomatosis pigmentovascularis but also cannot be used to predict the therapeutic outcome. Our objective is t o retrospectively study our series of laser-treated patients with the aim o f re-classifying nevus of Ota, so that such important issues can be taken i nto account. Study Design/Material and Methods: One hundred nineteen patients that had r eceived Q-switched laser treatment were recruited into the study. They were recalled for interview and examination for evidence of coexisting birthmar ks and extracutaneous involvement. Two observers assessed the pre- and post treatment clinical photographs for evidence of periorbital under-response ( panda's sign), defined as the degree of periorbital laser clearing signific antly less than clearing in the other area. Results: A total of 47.8% of the patients with periorbital pigmentation wer e considered by the observers to have significant periorbital under-respons e (panda's sign). Additionally, 10.1% had other birthmarks, and extracutane ous involvement was seen in 31.4% of the patients. Conclusion: Periorbital under-response is commonly seen in patients with pe riorbital pigmentation. Taking this and other factors into consideration, w e have proposed a new classification for nevus of Ota that allows for the p rediction of the clinical outcome of laser treatment. (C) 2001 Wiley-Liss, Inc.