There are six facters in its pathogenic causes:1 steroid-induced 2 alcohol-induced 3 radiation 4. blood diseases 5 blood vessel related disease 6 other factors eta.

• 认为本病的发病原因有以下几个方面：1、激素2、酒精3、辐射4、血液系统疾病5、血管源性疾病6、其他等。