Diagnosis

Definitive diagnosis of an umbilical hernia is by physical examination. Generally the contents of the hernia sack can be displaced back into the abdomen. This allows your veterinarian to determine the size of the hernia opening. The size of the hernia that is of most concern is that size which is similar to an intestinal loop. This size has the risk of allowing a loop of intestine to drop into the hernia and become trapped causing a life- threatening "strangulation". Hernias that are smaller, thus too small for a loop to enter, or larger, in which loops can freely come and go, are at lower risk for potential strangulation.

Occasionally, radiographs with contrast material may be used to diagnose strangulated hernias.

Abdominal ultrasound may be used to determine the size and contents of the hernia in some cases.

Causes

The exact cause of an umbilical hernia is unknown although most are thought to be inherited. It is most commonly a congenital malformation caused by flawed embryogenesis. The umbilical opening is normal until birth as it contains blood vessels that pass through from the mother to the fetus. This opening closes at birth in the normal pet and a hernia results if the opening fails to close.