Hair Collar Sign Associated with Scalp Aplasia Cutis Congenita

Aplasia cutis with 'hair collar sign'

“…The sign consists of a ring of long, dark, thick and rough hair surrounding the atrophic alopecic patches on the scalp. This condition may be associated with encephaloceles, meningoceles and heterotopic brain tissue 4. Recently, dermal melanocytosis and naevus flammeus have also been described in ACC 2 5.…”