One lesion, or occasionally, a small number of lesions, develops in children or adults. Lesions are found most commonly on the face, neck, upper part of the trunk, and arms. In young children, spider angiomas are common on the backs of the hands and fingers. Most lesions are unrelated to internal disease.
Many women develop lesions during pregnancy or while taking oral contraceptives.
These lesions are asymptomatic and usually resolve spontaneously 6-9 months after delivery or after discontinuing oral contraceptives. Numerous prominent spider angiomas are observed in patients with significant hepatic disease. A spider nevus consists of a central arteriole with radiating thin-walled vessels. Compression of the central vessel produces blanching and temporarily obliterates the lesion. When released, the threadlike vessels quickly refill with blood from the central arteriole.