TLDR  Trichoscopy is a quick and easy way to diagnose most genetic hair problems without invasive methods.   
  In 2008, a study involving 13 patients with known hair shaft disorders explored the use of trichoscopy, a non-invasive hair and scalp examination method, for diagnosing genetic hair shaft abnormalities. The study found that trichoscopy could effectively identify characteristic features of several conditions, including Netherton syndrome, monilethrix, woolly hair syndrome, pili torti, and pili annulati, without the need for invasive procedures. However, it was insufficient for diagnosing trichothiodystrophy, a condition characterized by brittle hair. The study concluded that trichoscopy could be a quick, easy, and patient-friendly method for diagnosing most hair shaft abnormalities.
            33 citations
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  September 2005   in “PubMed”
           33 citations
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  September 2005   in “PubMed”    Dutasteride successfully treated a woman's hair loss when other treatments failed.  
      16 citations
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  June 2005   in “Clinical and Experimental Dermatology”
           16 citations
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  June 2005   in “Clinical and Experimental Dermatology”    Twisted hair is rare in severe anorexia nervosa, found in only 2 out of 30 patients.  
      44 citations
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  January 2005   in “Dermatology”
           44 citations
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  January 2005   in “Dermatology”    Hair problems can be caused by genetics or the environment, and treatment should focus on the cause and reducing hair damage.  
      46 citations
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  December 2003   in “Advances in neonatal care”
           46 citations
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  December 2003   in “Advances in neonatal care”    Assessing newborn scalp hair can reveal important health information.  
               35 citations
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  September 2003   in “Archives of dermatology”    Tiger tail bands in hair are caused by wavy hair fibers with melanin, unlike straight fibers in normal hair.  
      15 citations
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  July 2002   in “Clinical and Experimental Dermatology”
           15 citations
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  July 2002   in “Clinical and Experimental Dermatology”    Hair microscopy is useful for diagnosing certain hair loss conditions but has limitations and must be interpreted carefully.  
      11 citations
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  March 2001   in “Clinics in Dermatology”
           11 citations
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  March 2001   in “Clinics in Dermatology”    Hair microscopy is useful for diagnosing hair disorders, but clear definitions are needed for accurate genetic analysis.  
      9 citations
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  January 2001   in “Dermatology”
           9 citations
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  January 2001   in “Dermatology”    Pili anulati may cause hair loss, proper diagnosis and treatment needed.  
    
  
        
      89 citations
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  March 2018   in “The Journal of Dermatology”
           89 citations
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  March 2018   in “The Journal of Dermatology”    Trichoscopy helps diagnose and monitor alopecia areata by looking at a combination of specific hair and scalp features.  
      November 2016   in “대한피부과학회지”
           November 2016   in “대한피부과학회지”    The document's conclusion cannot be summarized as it is not provided in a language I can understand.