Oedema is a normal reaction to inflammation or injury. This can be beneficial, because the increased fluid brings more white blood cells (which fight infection) to the area. There are two types of oedema; pitting and non-pitting. Pitting oedema is when the pressure is applied to the swollen area, and the indentation remains after the pressure is removed. Non-pitting oedema is when the indentation does not remain when pressure is removed.