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Fracture of the skull base
03-09-2009
The base of the skull is weakened by numerous holes, through which the blood vessels and nerves. With a skull fracture is a fracture line in the field of least resistance, which results in the ambiguity of its location. Therefore, it is worth recalling what the holes are located in the anterior and middle cranial fossa, within which may undergo fracture at the base of the skull in patients with fracture of the upper jaw.
In the anterior cranial fossa are:
• ethmoid ethmoid plate (lamina cribrosa ossis etmoidalis) with numerous holes in it through which the olfactory filaments;
• blind hole (foramen coecum), which communicates with the nasal cavity;
• Spotting a hole (foramen opticum), which passes through the optic nerve.
In the middle cranial fossa has the following openings:
• verhneglaznichnaya slit (fissura orbitalis superior);
• Round (foramen rotundum);
• oval (foramen ovale);
• spinalis (foramen spinosum);
• ragged (foramen lacerum);
• internal sleepy hole (foramen caroticum interna);
• opening of the facial canal (hiatus canalis fasialis);
• upper opening drum tubule (apertura superior canalis tympanici).
Examples are the most frequent location of the fracture line of the skull base:
▲ from a circular hole on the one hand through ephippium in the direction of the spinous and torn holes on the other hand;
▲ spinalis from the hole through the oval and round to the optic foramen with extension to the orbital surface of frontal bone, may damage the cavernous sinus;
▲ of hypoglossal nerve canal via the jugular hole and internal acoustic meatus (posterior fossa) to the neural foramen, and then – on the scales of the temporal bone. Broken pyramid of the temporal bone.
In the case of fracture of the skull base may be damaged basal parts of the brain, its trunk and cranial nerves. So you can install cerebral symptoms, stem disorders, signs of a lesion of cranial nerves. Often it may be noted bleeding from the ear (the pyramid of temporal bone fracture with rupture of the mucous membrane of the internal auditory canal and tympanic membrane), nasal (mucosal break of the upper wall of the nasal cavity, ethmoid bone fracture), mouth and throat secretions (ie, fracture sphenoid bones and rupture of the mucous shell vault pharynx).
Fracture of the upper jaw of Le Fort I, Le Fort II is accompanied by a fractured skull. At the turn of the anterior cranial fossa hemorrhage occur in the periorbital tissue (strictly in the area of the circular muscles of the eye), subcutaneous emphysema, bleeding from the nose. Nosebleeds happen at the turn of the bottom of the anterior cranial fossa in the area of the roof of the nose, the back wall of the frontal sinus or the lateral walls of the ethmoid sinus and mandatory break the nasal mucous membrane covering the bones. At the turn of the walls of the frontal sinus or lattice can be observed emphysema, periorbital area, forehead, cheeks.
One of the clinical signs of fracture of the skull base – a symptom score (hematoma in the area of age), resulting from hemorrhages in the soft fiber of persons age fracture of the upper jaw (intercilium, skupodobny shock). Later, here comes the blood from the skull base in the area of the upper wall of the orbit, penetrates retrobulbarno in fatty tissue and further penetrates loose fiber century.
Can liquorrhea of the nose (rhinorrhea). It should again be recalled that for the occurrence of rhinorrhea, except for fracture of the skull base, you need a break of the dura mater and nasal mucosa at the site of fracture. Nasal liquorrhea fracture occurs when the bottom of the anterior cranial fossa: in the perforated plate, the frontal, primary (sphenoid) sinuses, ethmoid cells. Outflow of CSF in the nose, possibly through the holes ethmoid and in the absence of bone damage caused by separation of the olfactory nerve fibers. This process stops after a few days after injury, when the wound of the dura mater, the nasal mucosa and a fracture gap in the bone zatamponiruetsya clotted blood (fibrin). It is known that posttraumatic liquorrhea – this outflow of cerebrospinal fluid from the cranial base bones in case of damage (or body) of the skull, dura and covering tissues (skin, mucous membranes). It may develop tightness in the subarachnoid space (Subarachnoidal liquorrhea), with injury walls of the ventricles (ventricular liquorrhea), basal cisterns (tank liquorrhea). Outflow of cerebrospinal fluid leads to a decrease in liquor pressure, accompanied by headache, vestibular disorders. Patients adynamic, take a forced situation – trying to lower his head down. In the case of liquor flowing into the throat provoked cough due to irritation of the mucous membrane. If you change the position of the patient in bed (from the back to side) may stop coughing.
Depending on the degree of increase the risk of primary liquorrhea fractures face and skull are located in the following sequence: fracture of the nose, upper jaw of Le Fort I, Le Fort II, fractures of the ethmoid bone. Liquorrhea observed more than 30% of patients with a fractured skull. In 70% of patients with liquorrhea developing hypotensive syndrome. Therefore, a statement of CSF hypotension in patients with fracture of the skull base should be forced to think about the liquor. When otlomlennoy displacement of the upper jaw are often damaged cranial nerves located in the ethmoid bone (I steam – olfactory); body and small wings of sphenoid bone (and a couple – visual) verhneglaznichnuyu passing through the slit, ie between large and small wings of sphenoid bone (III pair – the oculomotor, IV couple – block, VI pair – outlet).
Reduction or loss of smell in patients with fractures of the upper jaw of the type of Le Fort I, II demonstrates the damage the olfactory nerve (I par). Reduction of visual acuity, loss of parts of the visual fields, ie central and paracentral cattle show injury of the optic nerve (II couple). If the patient does not open his eyes partially or completely damaged oculomotor nerve (II couple).
If the fracture is in the upper orbital fissure, may have oculomotor violations – signs of a lesion III, IV, VI pairs of cranial nerves. Thus, if a patient does not open his eyes and there exotropia, raznostoyanie eyeballs on a vertical, violation of the mobility of the eyeball upwards, downwards, inwards, ptosis, mydriasis, – the patient struck by the oculomotor nerve. Deviation of the eyeball upward and medially, restricting movement of the eyeball down and out, diplopia in downward gaze characteristic lesion of the nerve block. Esotropia, the violation of the mobility of the eyeball KPA-Ruzhi, diplopia in the horizontal plane are signs of damage to the abducens. Fractures of the anterior cranial fossa leads to the message with its eye-socket, or clauses of the nasal cavity.
Gap fracture of the middle cranial fossa through large wings and body of sphenoid bone, ie as at the turn of the type of Le Fort I. This damage can arise III, IV, VI, VII, VIII pairs of cranial nerves. Consequently, the patient, either partially or fully opens his eyes. May mark the limits of motion of the eyeball medially, esotropia. It is rarely profuse bleeding from the nose as a consequence of rupture of the internal carotid artery, as well as damage to the walls of the sphenoid sinus [Annunciation NS, 1994]. With such a fractured skull liquorrhea occurs when the body sphenoid bone fracture, rupture of the dura mater and nasal mucosa body. This small wound can be seen using a dental mirror. In the horizontal position released cerebrospinal fluid leaks on the back of the throat and the patient swallows it. When the head is tilted forward, it flows out through the nose.
When fractures of the facial skeleton, extending to the base of the skull, liquorrhea has important clinical significance, since the cavity freely communicates with the nasal cavity is contaminated by microorganisms, with the frontal, latticed, sphenoid sinuses, the cells of the mastoid process. Cerebrospinal fluid, infecting flowing into these sinuses, and there is a real threat to development
meningitis.
The patient with liquorrhea from the nose in the early period shows a strict bed rest. It is desirable to prevent coughing and sneezing, as well as air under high pressure can penetrate into the cranial cavity – there pnevmotsefaliya. His head is better to give the victim elevated position.
Oseltamivir prescribe antibiotics.
With a skull fracture may occur Subars-noidalnye hemorrhage. The localization of the fracture is determined from the analysis of data kraniogramm, the presence of the ear or nasal liquorrhea, on the grounds of the defeat of certain cranial nerves. Is shown conducting the dehydration therapy, which reduces the pressure and production of cerebrospinal fluid, as well as handling repeated lumbar puncture.
In addition to the fracture of the skull base, with CoN ™ can be detected concussion, contusion of the brain, intrakra-nialnye hematoma. Symptoms of expression also need to know your dentist to determine the tactics of treatment of patients.
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