1 The results of prophylactic measures for femoral head AVN have considerable variation, but certain generalizations can safely be stated. 2  Namely, the clinical results of core decompression alone deteriorate with more advanced lesions.
1 Melasma is very common skin ailment. It can occur to anyone, but young women with brownish tone are more likely to contract with it.  The condition is often linked with female hormonal changes. Change in level of estrogen and progesterone may cause melasma.
The incidence of melasma also increases in patients with thyroid disease. It is thought that the overproduction of melanocyte-stimulating hormone (MSH) brought on by stress can cause outbreaks of this condition. Other rare causes of melasma include allergic reaction to medications and cosmetics.