Therapy of the skull base fracture

Introduction

The therapy of a skull base fracture depends mainly on the extent of damage to surrounding structures caused by the fracture. Not every basal skull fracture requires immediate surgery. However, there are some situations in which immediate intervention is necessary.

The most important of these is open craniocerebral trauma, which is usually caused by accidents. Involvement of cranial nerves is also an absolute indication for surgery, e.g. if the ocular nerve (second cranial nerve) is affected by constriction and blindness is imminent, or if the seventh cranial nerve, which is responsible for the facial muscles, is damaged and its failure leads to facial paralysis (facial paresis). Another situation in which urgency is required is when there is a massive loss of cerebrospinal fluid (liquor) and blood or when the head is impaled with a foreign body.

Conservative therapy

If there is no displacement of the fracture ends, a wait-and-see, conservative therapy attempt can be started with regular monitoring of bleeding and inflammation. If the above-mentioned situations do not occur, this can often be sufficient. Even in cases of eardrum defects or accumulation of blood in the middle ear, healing is often achieved by waiting.

If water from the nerves leaks out of the ear (otogenic cerebrospinal fluid), this is treated with antibiotics to prevent the immigration of bacteria and thus inflammation. One then treats symptomatically e.g. with antivertiginosa for dizziness or a pain medication. It is being discussed whether prophylactic administration of antibiotics is useful to avoid dangerous meningitis or encephalitis. Opinions differ on this point; it is certainly sensible to discuss this topic with the treating physician in each individual case, depending on the severity of the injuries.

Operation

The situation is different, however, if one of the above-mentioned situations occurs, or if there is an escape of cerebrospinal fluid from the nose (rhinogenic liquorrhea). Here, surgery is indicated. The surgical procedure usually consists of removing the pressure from the tissue damaged by the trauma or fracture, thus preventing irreversible damage by relieving the pressure.

In addition, the fracture ends must be brought back into the correct anatomical position so that healing and, above all, bone stability can be ensured. This is because unstable fractures, or the bones growing together in the anatomically incorrect position, can also lead to secondary pressure damage to nerves or vessels in the cranial and/or facial skull area. In some cases, injuries to the hard meninges (dura mater) must be sutured again, and the bone defects must be covered with filling material.

In the best case, this is done using the body’s own tissue, e.g. so-called fascia (= connective tissue that envelops muscle groups, for example) or fibrin glue (= two-component glue that connects tissue with each other). With these substances, the risk of a rejection reaction of the body is much lower than with synthetically manufactured products. If there are larger defects, metal plates or pins can also be used to stabilize the fracture ends so that they can grow together and thus restore the necessary stability.

However, the use of these metallic parts is rather rare. If the skull has been pressed in by the fracture, it will be lifted again during the operation. If a strong bleeding occurs due to the involvement of vessels, the injured vessel must be closed again with a vascular suture.

The internal carotid artery (A. carotis interna) is often affected, since its course at the base of the skull is at risk in fractures of the skull. If it is necessary to open the skull to treat the fracture, this is usually the responsibility of the neurosurgeon. However, in the case of fractures of the facial skull, the maxillofacial surgeon may also be used. If the eyes are affected by injury to the second cranial nerve (N. opticus) or the hearing is affected by involvement of the eighth cranial nerve (N. vestibulocochlearis), the ophthalmologist or ENT specialist may also be involved in the treatment.