Ocular Finding in Alopecia Areata

Alopecia areata (AA) is a common, idiopathic and sometimes recurrent non-scarring type of hair loss. Several etiological factors, including psychological, trauma-related, genetic and autoimmune factors have been considered as possible etiological factors . A T cell-mediated autoimmune mechanism in genetically vulnerable individuals is the most acceptable etiology. Alopecia areata presents clinically with well demarcated patches of non cicatricial hair loss in any hair bearing area with no remarkable gender preference. Although AA may occur at any age, incidence is high among younger age groups. In fact, it is the most common form of alopecia seen in children. Various clinical patterns of alopecia have been described as patchy, diffuse, reticulate, ophiasis and ophiasis inversus. Depending on the extent of hair loss, it can be classified into alopecia subtotalis, alopecia totalis (complete loss of scalp hair), and alopecia universalis (complete loss of body hair). National Alopecia Areata Foundation has devised "Severity of Alopecia Tool Score" (SALT score) as a measure of disease severity. Scalp is divided into 4 areas, namely, Vertex-40% of scalp surface area; right and left profiles-18% each and posterior scalp aspect-24%. SALT score is the sum of percentage of hair loss in the above mentioned areas.