Hair root characteristics of the human scalp hair in health and disease

Morphological data on hair follicles have been available for over a hundred years, but only in recent years has a substantial advance been made in our knowledge of types and distribution of hair, its structure, metabolism, biochemistry and clinical patterns, and hormonal influences on hair growth. Hair plucking followed by microscopic examination has been used as a diagnostic procedure in the past two decades. Van Scott et al. ( 195 7) were first to standardize the technique of human hair plucking (epilation) and to design criteria for assessment of the morphology of the various phases of the hair growth cycle and of aberrant hair roots. Subsequent authors, however, have used modifications of this technique and applied varying and conflicting criteria in assessing the morphology of the various phases of the hair growth cycle and of aberrant hair roots, General acceptance of a reliable uniform technique, and equally strict criteria for different morphological hair root structures, can ensure that comparable data are obtained. The findings presented in this thesis are confined to human scalp hair roots. The preparation of a hair root status involves a simple, atraumatic technique of obtaining material, and the study of the physiology and pathology of hair growth in a manner which could be very useful in evaluating hair diseases and determining appropriate therapy (PeereboomWynia 1975; Peereboom-Wynia and Beek 1977).