X-ray signs of damage to the skull and brain

Radiation studies in the affected patients are carried out by the appointment of a surgeon, traumatologist or neurologist (neurosurgeon). The basis for this appointment is head trauma, cerebral palsy (headache, nausea, vomiting, impaired consciousness) and focal neurological symptoms (speech, sensitivity, motor impairment, etc.). In the direction of the clinician, a presumptive diagnosis must necessarily be indicated.

The severity of damage is determined not so much by breaking the integrity of the bones of the skull, as by damage to the brain and its membranes. In this regard, in the vast majority of cases, radiation study in acute trauma should be the performance of CT. It must be remembered that in some cases the damage seems easy and the radiographs do not even show a breach of the integrity of the bones, but because of the ongoing intracranial hemorrhage, the patient's condition may worsen significantly in the following hours and days.

Conventional radiographs are shown mainly with depressed fractures, when the fragments are mixed into the cranial cavity. They can also be used to determine the mixing of calcified intracranial formations, normally located midway (pineal gland, sickle-shaped process), which is an indirect sign of intracranial hemorrhage. In addition, on radiographs, it is sometimes possible to detect small linear fractures that elude the radiologist when analyzing CT. However, let us repeat once again that CT scan is the main radiation method for studying head injuries.

When performing radiation research in patients with damage to the skull and brain, the radiologist should answer three questions:

1. Is there a violation of the integrity of the bones of the skull?
2. whether fracture is accompanied by the insertion of fragments into the cavity of the skull and damage to the eye sockets, the paranasal sinuses and the middle ear cavity;
3. is there any damage to the brain and its membranes (swelling, hemorrhage).

Among the damages of peacetime, linear fractures (cracks) of the bones of the cranial vault predominate. In the overwhelming majority of cases, they arise at the site of application of force (this fact always makes it easier to identify the crack). Fracture is defined as a sharp, sometimes zigzag-shaped, sometimes splitting band with slightly uneven edges. Depending on the nature of the injury, the position and extent of the crack are very diverse. They can affect only one plate or both, go to the cranial suture, causing its discrepancy.

In addition to cracks, there are perforated, depressed and comminuted fractures. With them, as noted above, it is especially important to establish the degree of displacement of fragments in the cranial cavity, which is easy to perform with the help of sighting images. A significant displacement of the fragments is observed in fractures of gunshot origin. With blind wounds, it is necessary to determine the presence and precise localization of foreign bodies, in particular to establish whether a bullet or a fragment is located in the cavity of the skull or outside it.

Fractures of the base of the skull, as a rule, are a continuation of the cracks of the arch. The fissures of the frontal bone usually descend to the frontal sinus, the upper wall of the orbit or the latticed labyrinth, the cracks of the parietal and temporal bones to the middle cranial pit, and the cervical fissures to the posterior cranial pit. When choosing the method of radiography, clinical data are taken into account: bleeding from the nose, mouth, ears, the discharge of cerebrospinal fluid from the nose or ear, bleeding in the eyelid or soft tissue region of the mastoid process, disruption of the function of certain cranial nerves. According to clinical and radiographic signs, the doctor produces images of the anterior, middle or posterior cranial fossa.

On computer tomograms, the area of fresh hemorrhage has an increased density, position, size and shape of it depend on the source and localization of bleeding. The density of the shadow of the hematoma increases in the first 3 days after the injury and then gradually decreases within 1 to 2 weeks.

Intracerebral hematoma is usually well-delimited, and at considerable sizes it pushes out neighboring brain structures (this effect was called the "mass effect"). Around the hematoma may be a zone of reduced density (hypodensitive zone). Its substrate is edematous brain tissue. If the hemorrhage penetrates the ventricle of the brain, then the area of increased density takes the form of the corresponding part of the ventricle. Trauma can cause swelling of the brain substance due to edema and hyperemia. In this case, a zone of increased density of a diffuse or focal character is noted on the CT. It is most clearly visible 12-24 hours after the injury.

Hemorrhage can occur under the dura mater or between it and the bones of the skull. Fresh subdural and epidural hematomas also form on the computer tomograms an area of high and uniform density, elongated, often oval, which is due to the image of the cranial bones.

At the same time, hemorrhage in the brain tissue can be observed, and with a large subdural hematoma - mass effect. Subsequently, the density of the hematoma decreases and becomes even less than the density of the brain substance.

CT scan allows to detect hemorrhage in the paranasal sinuses or penetration of air from these sinuses into the cavity of the skull - pneumocephaly. The mass effect is also established from the displacement of the median structures in a one-dimensional ultrasound study.

The role of MRI in the examination of patients with skull fractures is very limited. Its main purpose is to monitor the state of the brain in the process of treatment.

Contusions of the brain are often traumatic injuries, manifested by brain edema with or without hemorrhage. Sometimes a bruise can form a true hematoma. Damages are often multiple, a significant part of them are in the frontal and temporal lobes.

With CT, edematous tissue manifests itself as a region of reduced density. The picture of edema with MRI depends on the method of obtaining the image: on T1-weighted tomograms, the edema zone looks hypo-intensive, on T2-weighted - hyperintensive. Hemorrhage in the brain is detected with CT or MRI.