Thursday, December 24, 2015

image challange 70

Nevus of Ota in a 20-year-old woman. Hyperpigmentation around the orbita. The hyperpigmentation extends into the sclera.

Hyperpigmentation around orbit            Hyperpigmentation extends into sclera

Nevus of Ota. Ota’s nevus (nevus fuscocaeruleus ophthalmomaxillaris) was first described by Ota in
1939.It is characterized by blue–black or gray–brown dermal melanocytic pigmentation and typically occurs in areas innervated by the first and second branches of the trigeminal nerve. Mucosal pigmentation may occur involving conjunctiva, sclera, and tympanic membrane (oculodermal melanocytosis),  or other sites.

It is most frequently seen in the Asian population, has a female predominance, and is usually congenital, although appearance in early childhood or at puberty has been described. Nevus of Ota is now subclassified as mild (type 1), moderate (type 2), intensive (type 3), and bilateral (type 4). Bilateral cases should be differentiated from Hori nevus, which is acquired, does not manifest mucosal involvement and is less pigmented .

Malignant melanoma may rarely develop in a nevus of Ota. This necessitates careful follow-up of the lesion, especially if it occurs in Caucasian patients, in whom malignant degeneration seems to be more frequent. Malignant melanocytic tumors in association with nevus of Ota have been shown to arise in the chorioidea, brain, orbit, iris, ciliary body, and optic nerve. In addition, association with ipsilateral glaucoma and intracranial melanocytosis has been described .


Post a Comment