How do you recognize cerebral pressure signs in CT?
Since CT scans only take a few seconds, they are the method of choice for clarifying suspected elevated intracranial pressure in emergency situations, for example as a result of craniocerebral trauma. An enlargement of the so-called cerebrospinal fluid spaces of the brain is considered a particularly impressive cerebral pressure sign in CT and occurs when the increase in cerebral pressure results from a disturbance in the outflow of cerebrospinal fluid (brain water). The cerebrospinal fluid contained in the cerebrospinal fluid spaces is shown in black on the CT, so that the spaces can be recognized as a butterfly-like structure in the center of the image in the usual (horizontal) section of the CT. An asymmetry or compression of the cerebrospinal fluid spaces also indicates an increased intracranial pressure, then more likely caused by a trauma or tumor.
Also important is an examination of the large cranial opening (foramen magnum). Here, attention is paid to whether the space between the brain stem and the cranial bone is normal or reduced, whereby the latter would be interpreted as an indication of intracranial pressure. Elapsed cerebral convolutions indicate cerebral edema and are therefore also considered to be cerebral pressure signs. In addition, CT can also be used to search for the cause of increased intracranial pressure: Causes that can be clearly identified in the CT are, for example, tumors or other obstacles that block the outflow of cerebral water and can thus lead to an expansion of the cerebrospinal fluid and an increase in intracranial pressure. If such indications are found in the CT, an additional MRI scan is often taken to provide more precise images.
How do you recognize cerebral pressure signs on an MRT?
Although MRI and CT differ considerably in terms of their functional principle and the representation of different body structures, the same basic rules apply to the detection of brain pressure signs in MRI as in CT (see above). For example, the MRI image focuses on the cerebrospinal fluid and the space around the brain stem. The MRI usually provides more precise images and does not involve any exposure to X-rays, but is also significantly more cost and time intensive than CT. For this reason, the MRI is sometimes only called in when the CT images have not provided conclusive results. In emergencies, CT is preferred in any case due to time pressure.
