Cicatricial Alopecias (syn. scarring alopecias)
Uncommon and clinically diverse disorders that result in permanent and irreversible loss of scalp hair. These disorders may be primary, with the follicle itself being the target of the disease process, or secondary, where hair follicles are destroyed as part of a more generalized tissue-damaging event (e.g. deep skin infection, thermal burn, trauma, or ionizing radiation). Clinically it is characterized by the disappearance of visible follicular ostia within an area of alopecia.