Mastoiditis is a disease faced by many people. But not every person knows what the mastoid processes are and where they are located. What is the structure of this part of the temporal bone? How dangerous is the inflammation of these structures, and what can cause the disease? Many people are interested in these questions.
Where are the mastoid processes?
The mastoid process is the lower part of the temporal bone. If we talk about its location, then it is located below and behind the main part of the skull.
The process itself has the shape of a cone, the base of which borders on the area around the middle cranial fossa. The apex of the process is directed downward - some muscles are attached to it, in particular the sternocleidomastoid muscle. The base of the cone borders on the hard shell of the brain (which is why infectious inflammation of this area is so dangerous, because pathogenic microorganisms can penetrate directly into the nervous tissue).
In the subcutaneous tissue that covers this part of the temporal bone, there are lymph nodes and vessels, behind the ear vein and artery. Here are the branches of the small and large ear nerves.
It is worth noting that the mastoid processes can have a different shape. In some people they are long with a narrow base, in others they are short, but with a wide base. This anatomical feature is largely dependent on genetic inheritance.
The structure of the mastoid process
As already mentioned, this part of the temporal bone is shaped like a cone. In modern anatomy, it is customary to distinguish the so-called Shipo triangle, which is located in the anterior upper part of the process. Behind the triangle is limited by the mastoid scallop, and in front its border runs at the back of the external auditory canal.
The internal structure of the process is somewhat reminiscent of a porous sponge, as there are many hollow cells, which are nothing more than air-bearing appendages of the tympanic cavity. The number and size of such cells can be different and depend on the characteristics of the growth and development of the organism (for example, inflammation of the ear in childhood leaves its mark on the structure of the mastoid process).
In the region of the Shipo triangle is the largest cell, called antrum or cave. This structure is formed in close interaction with the tympanic cavity and is present in every person (as opposed to smaller cells, the number of which can vary).
Types of mastoidoffshoots
As already mentioned, the mastoid process of the temporal bone can have a different internal structure. In the first year of a baby's life, an antrum is formed. Up to three years, there is an active pneumatization of the internal tissues of the process, which is accompanied by the appearance of hollow cells. By the way, this process lasts throughout a person’s life. Depending on the number and size of cavities, it is customary to distinguish several types of structure:
- Pneumatic mastoid processes are characterized by the formation of large cells that fill the entire interior of this bone structure.
- With the sclerotic type, there are practically no cells inside the process.
- In the diploetic mastoid process are small cells that contain a small amount of bone marrow.
It is worth noting that most often doctors find traces of mixed cavity formation in this part of the temporal bone. Again, everything here depends on the genetic characteristics of the organism, the pace of development, as well as the presence of injuries and inflammatory diseases in childhood and adolescence.
Inflammation of the mastoid process and its causes
A disease in which inflammation of the tissues of the mastoid processes is observed is called mastoiditis. The most common cause is infection, and pathogens can enter this area of the skull in different ways.
Most often, such a disease develops against the background of otitis media. The infection enters the mastoid process of the temporal bone from the tympanic cavityor ear canal. In some cases, inflammation develops with a direct trauma to the skull in the temple or ear. The source of infection may be inflamed lymph nodes located in this area. Much less often, systemic blood poisoning is the cause of the disease.
Main symptoms of inflammation
The main signs of mastoiditis largely depend on the severity and stage of development of the disease. For example, in the initial stages, it is very difficult to distinguish inflammation of the mastoid process from ordinary otitis media.
Patients complain of sharp, shooting pain in the ear. There is an increase in temperature, weakness and body aches, headaches. There is a discharge from the ear canal.
In the absence of therapy or insufficient treatment (for example, stopping antibiotics too quickly), the clinical picture changes. The mastoid process of the ear is gradually filled with pus, and under pressure, the bony septa between the cells are destroyed. The skin and subcutaneous tissues behind the auricle swell and turn red, become hard, hot to the touch. The earache gets worse, and thick, purulent masses come out of the ear canal.
Inflammation from the cavities of the mastoid process can spread under the periosteum - pus accumulates already in the subcutaneous tissue layer. Quite often, the abscess ruptures on its own, resulting in a fistula on the skin.
How dangerous can the disease be? Most Common Complications
As already mentioned, the mastoid process is located behind the ear and borders on important organs. Therefore, the lack of timely therapy is fraught with dangerous consequences. If the focus breaks into the cavity of the middle and inner ear, labyrinthitis develops. Inflammation of the inner ear is accompanied by tinnitus, hearing loss, as well as damage to the organ of balance, which leads to impaired coordination of movements.
Mastoid processes border on the hard shells of the brain. The infection can spread to nerve tissue, leading to meningitis, encephalitis, and sometimes abscesses.
Dangerous is the penetration of infections into the vessels responsible for the blood circulation of the brain - this is fraught not only with inflammation of the vascular walls, but also with the formation of blood clots, blockage of arteries and even death.
To complications of mastoiditis can be attributed to the defeat of the facial nerve. After all, the mastoid process behind the ears is very close to the nerve fibers.
How is mastoiditis treated?
As you can see, mastoiditis is an extremely dangerous disease, so adequate therapy is simply necessary here. Any delay and attempts at self-treatment can lead to a lot of dangerous complications.
As a rule, treatment is carried out in a hospital, where the doctor has the opportunity to constantly monitor the patient's condition. Patients are prescribed intravenous antibiotics to help fight the bacterial infection. In addition, it is necessary to create conditions for the free exit of purulent masses from the ear canal.
When neededmastoid trepanation?
Unfortunately, conservative therapy is effective only in the initial stages of mastoiditis. If pus began to accumulate in the cavities of the lower part of the temporal bone, then simple surgical intervention is necessary. Trepanation of the mastoid process begins with the opening of the bone wall of the process. After that, the surgeon, using tools, cleans the tissues from pus, treats them with antiseptics and antibacterial solutions. Then a special drainage system is installed, which provides easy and quick removal of secretions, as well as local administration of antibiotics.
