Is it really lice OR hair casts?

I've been at war with my daughter's hair for shy of 6 years now. Ever since she was 2 and in day care the doctors pegged her for having hair lice. Over the past 6 years she's been treated with numerous posionous lice treatments, and the "nit" looking things keep coming back! She has "never" had itching/redness of the scalp or any live louse. The "nit" looking things are ALL over her head but are ONLY located in the top section of her head no where else.The "nits" also move up and down the hair shaft, and if you pull one off and run it between your fingers, it completely breaks up.  If it's been this many years why hasn't myself or my husband gotten lice? I know it's very easy to spread it, so why not us? Is it really lice? My daughter is half american half Indian (Asian decent) I read some where that being of Asian decent is sometimes a factor in what you call hair casts. Please, please help me. We live in a small town...the doctors say it's lice, but we don't think so. How can we be sure of what it is? Thank you so much.
~ Amanda Salisbury, MD

[jagesh50]

When your daughter was treated for lice,it would have been expected to treat the entire family as a group.Sure, hair casts are look alike of nits.So best to treat as family, and see whether it recurs.