Eyeball sockets layer separated from the adipose tissue that acts as a shock and called periorbital fiber. From her eyelid skin separates the connective tissue membrane - orbital septum, holding the adipose tissue inside the eye socket.
Until recently it was believed that the bags under the eyes occur when the connective tissue membrane loses its elasticity, stretch, sag outwards and can not hold the fat inside, forming a kind of hernia. Therefore, when performing plastic surgery on the lower eyelids to remove "bags" surgeons, primarily sutured and reinforced orbital septum.
However, in the summer of 2008 scientists proved that the appearance of bags under the eyes caused by an increase in the periorbital tissue. When this increase exceeds the orbital septum tension, fat sticks out her out, going beyond the orbit. And to increase the amount of adipose tissue may due to its expansion or edema.
"Sacks", which appeared as a result of edema, usually most noticeable after a sleep and reduced or completely pass late in the afternoon, when under the influence of gravity and stimulate blood circulation fluid flowing from the upper body.
"Bags" associated with the growth of adipose tissue are constant and do not depend on time of day.