A 14-year-old male presented with an alopecic plaque in his occipital area. Skin exam revealed a well-defined, hyperpigmented plaque with a velvety texture, resembling acanthosis nigricans (AN) ( Figure 1A ). Trichoscopy showed broken hair shafts and yellow dots, as well as a few exclamation mark hairs. Histology manifested mild acanthosis, hyperkeratosis, and papillomatosis, with no visible nests of melanocytes ( Figure 1B ). Due to these findings, the patient was diagnosed with nevoid AN. This skin disorder, also known as RAVEN (round and velvety epidermal nevus) is a rare entity, which appears at or before puberty [ 1 , 2 ] .

The skin disorder RAVEN has no predilection for intertriginous or flexural areas. Most reported cases are unilateral and located on the chest, abdomen and umbilical, or retroauricular area. We found no other reports of RAVEN involving the scalp in the literature. As it is a benign condition, RAVEN requires no treatment or follow-up, and has not been found to be associated with any underlying disorder [ 1 , 2 ] .

The closest differential diagnosis is with epidermal nevus. Although they are clinically very similar, RAVEN is usually velvetier, and histology plays an essential role as it shows compact hyperkeratosis, papillomatosis and limited acanthosis as compared to epidermal nevi. Other differential diagnosis include confluent and reticulate papillomatosis, ichthyosis hystrix, and the hyperkeratotic type of seborrheic keratosis. In our case, the velvety texture of the lesion, as well as the histology, which showed mild acanthosis, excluded epidermal nevus.

RAVEN can resemble epidermal nevi or AN. Dermatologists should be aware of this entity and should consider it in the differential diagnosis of pigmented skin lesions.