Etymology: L, crena, notch. the formation of notches or leaflike scalloped edges on an object. Red blood cells exposed to a hypertonic saline solution acquire a notched, shriveled surface as a result of the osmotic effect of the solution. They are then called crenated red blood cells. crenate, crenated, adj.
Occipital neuralgia is the neck/head pain that results from injury or irritation to the occipital nerves. It can be caused by trauma, such as a car accident, by a pinched nerve root in the neck (from arthritis, for example) or by âtightâ muscles at the back of the head that entrap the nerves.
Occipital Nerve Block. An occipital nerve block is an injection that numbs the nerves at the back of the head. There are four nerves on each side of the scalp. Occipital nerves allow us to feel sensations in the scalp. An occipital nerve block is done to decrease headache pain, caused by migraine, injury (concussion), muscle tightness or occipital neuralgia. The medicine used is either a local anesthetic or a combination of a local anesthetic and a steroid. The medicine is placed around the occipital nerves, which are located just beneath the skin, in the back of the head. The occipital block is usually done in the office.