RT Book, Section
A1 Hordinsky, Maria K.
A2 Soutor, Carol
A2 Hordinsky, Maria K.
SR Print(0)
ID 1190939504
T1 Hair Disorders
T2 Clinical Dermatology: Diagnosis and Management of Common Disorders, 2e
YR 2022
FD 2022
PB McGraw-Hill Education
PP New York, NY
SN 9781264257379
LK dermatology.mhmedical.com/content.aspx?aid=1190939504
RD 2024/04/19
AB The  hair  follicle  is  a  complex  structure  which  produces  a  hair  fiber  consisting  of  a  cortex,  medulla  and  cuticle  (Figures  30-1,  30-2).  Hair  follicles  demonstrate  the  unusual  ability  to  completely  regenerate  themselves.  Hair  grows,  falls  out,  and  then  regrows.  In  the  normal  human  scalp,  up  to  90%  of  hair  follicles  are  in  the  growth  phase  called  anagen,  1%  in  the  transition  phase  catagen  and  up  to  10%  in  telogen  or  the  loss  phase.  The  anagen  phase  lasts  approximately  3  years,  catagen  2–3  weeks  and  telogen  3  months.1