How does a nevus of Ota differ from a nevus of Ito?

The nevus of Ota (also called nevus fuscoceruleus ophthalmomaxillaris) is characterized clinically as a blue to gray hyperpigmentation of the skin, mucosa, and conjunctiva in the distribution of the trigeminal nerve. Less commonly, it may also involve the meninges (meningeal melanocytoma), where it may develop a hemorrhage or, rarely, a malignant melanoma. Histologically, it is composed of heavily melanized dendritic dermal melanocytes in the upper dermis. The nevus of Ito is similar in histology to the nevus of Ota but is distributed along the neck and shoulder in the distribution of the posterior supraclavicular and lateral cutaneous brachial nerves. Both lesions are considered congential dermal melanocytoses and are more common in Asians and African-Americans. About 80% of all reported cases have been woman.