How do you make the diagnosis?
In order to be able to direct an initial suspicion of an increased intracranial pressure, the symptoms must be asked in detail. The body can compensate for a certain increase in pressure. Depending on the individual, a further increase may cause nausea, headaches, tiredness and nervousness.
In the further course of the disease, there is an increase in blood pressure, a reduced heart rate and slight shortness of breath. At this stage at the latest, the affected person must be examined for certain cerebral pressure signs. A popular test procedure for this is the examination of the eye.
In the back of the eye, water retention, a so-called “congestion papilla“, can often already be seen. If increased intracranial pressure is suspected, this can be determined with the aid of many test procedures. After drilling a hole in the skull, a measuring probe can be invasively inserted at various points in the brain.
This probe can permanently measure the pressure so that it can be read on a monitoring monitor. The invasive method always carries a risk of infection. Ultrasound examinations of the optic nerve can also offer an alternative to invasive measurement.
If there is a strong suspicion of increased intracranial pressure, a CT or MRI image can also be taken immediately. Certain signs in the radiological image indicate the increased pressure. If a tumor or other structural change in the skull is responsible for the pressure, it can also be diagnosed here.
The description of the symptoms by the patient, the examination of the ocular fundus and the preparation of a CT or MRI image of the skull can provide good indications of the presence of increased intracranial pressure, but not an exact value for the intracranial pressure. In some cases, however, e.g. to monitor the course of a craniocerebral trauma, doctors need an exact measurement of the intracranial pressure.This can take the form of a brain probe: In this case, several small probes are placed at different locations in the brain after a small hole has been drilled in the skull. However, since this procedure always involves a certain risk of infection, it is reserved for emergencies.
A gentler alternative is the ultrasound examination of the optic nerve, which does not provide an exact value for the intracranial pressure either, but only documents its effects on the nerve. Like computed tomography of the head (CCT), magnetic resonance imaging (MRI) is one option for imaging diagnostics in cases of increased intracranial pressure. The advantages of MRI over CCT are the absence of radiation exposure and the better recognition of brain details, even though the duration of the examination is significantly longer in comparison.
In addition to the typical signs of increased intracranial pressure, it is also possible to identify the causes of increased pressure, such as bleeding or space-occupying processes (e.g. tumors in the brain). Depending on the underlying cause of the increased intracranial pressure (e.g. space-occupying process, cerebral edema, cerebrospinal fluid flow disturbance, etc. ), different imaging signs can be detected in both MRI and CCT: if the pressure is caused by a cerebrospinal fluid flow disturbance, this can often be detected by enlarged cerebrospinal fluid spaces, whereas cerebral edema is caused by narrowed ventricles and cerebrospinal fluid spaces and an elapsed surface relief of the brain.
Space-occupying processes can be detected by a shift in the center line or displacement or entrapment of brain tissue. Increased cerebral pressure can impair the function of the nerve responsible for constriction of the pupil. Consequently, a dilation of the pupil is considered to be a sign of cerebral pressure, as is a weakening of the so-called light reaction. The latter term describes the narrowing of the pupil as a result of irradiating the eye with a lamp. Both the dilation of the pupil and the light reaction are difficult for untrained persons to assess, which is why a physician should be consulted in case of uncertainties and/or further symptoms.