As a medical emergency, intracranial hypertension can have multiple causes. What are the specific symptoms of intracranial hypertension? What is the support? The explanations of Pr Patrick Mertens, professor of anatomy, neurosurgeon and head of the neurosurgery federation of the Hospices Civils de Lyon.
In adults as in children, an increase in pressure in the brain (oedema, cerebral inflammation, accumulation of cerebrospinal fluid – lcr…) “stuck” in the cranial box can lead to intracranial hypertension. Compression can then have various important clinical consequences and constitutes a medical emergency for the patients concerned. What are the signs and risks of intracranial hypertension (vision, pain, etc.)? What tests can make the diagnosis? What is the support? All the answers from Pr Patrick Mertens, neurosurgeon.
Intracranial hypertension: what are we talking about?
Acute or chronic, intracranial hypertension (ICHT or ICH) is a medical emergency. It can affect the brain such as vision and, in some cases, lead to death. Its causes can be many but it can also be idiopathic. In particular, it can cause cerebral edema, compression and cerebral engagement and affect the proper circulation of cerebrospinal fluid (crl). Urgent diagnosis and treatment are needed.
Inside the cranial box, a regulated pressure depending on several parameters (blood pressure and cerebrospinal fluid flow, for example) ensures proper cerebral functioning. “Under the effect of a variety of possible causes, an abnormal increase in the pressure inside the cranium can occur. This is called intracranial hypertension (HTIC)”emphasizes Pr Patrick Mertens, professor of anatomy and neurosurgery at the Hospices Civils de Lyon.
Intracranial hypertension: a bundle of multiple causes
There are multiple causes that can cause an increase in intracranial pressure. “Inside the cranial box, any increase in volume of a content will lead to an increase in cerebral pressure and a dysfunction in the regulation of fluids, in particular the cerebrospinal fluid (CSF)”, explains Professor Patrick Mertens. This is the case in many hemorrhagic pathologies (presence of a hematoma), a tumour, venous thrombosis, cerebrospinal fluid circulation disorders with hydrocephalus which will lead to an accumulation of fluid in the the cranial box (cerebral oedema). However, if the causes can be varied, there are also intracranial hypertension without identified causes. “This is called idiopathic intracranial hypertension.continues the specialist.
Intracranial hypertension (HTIC) can be associated with an acute episode, under the effect of a sudden increase in pressure, or remain chronic and evolve quietly for a long period. It can also be linked to taking certain medications (hormonal treatments, lithium, etc.). “Certain cerebral malformations with cerebrospinal fluid (cSF) circulation disorders lead to recurrent episodes of intracranial hypertension (htic) requiring emergency treatment”, continues the specialist. If there is no specific profile, people with obesity are more at risk.
A medical emergency
Without being truly specific, certain symptoms should alert. Thus, bilateral headaches accompanied by nausea and vomiting (which relieve the headaches), are suggestive signs of intracranial hypertension. In addition, visual disorders (oculo-motor disorders, visual blurring, etc.) are often associated. “The presence of visual disturbances are tangible signs of a certain seriousness. At this stage, intracranial hypertension is already elevated,” continues the specialist. Other symptoms (dizziness, ringing in the ears, cognitive disorders characterized by a general slowing down, a form of apathy, etc.) should also alert.
Brain Compression and Commitment
Once established, intracranial hypertension (HTIC) can cause serious medical complications, whether cerebral or visual. “At the cerebral level, the brain can be pushed back by pressure, by a hematoma, by a tumor or by a post-traumatic injury, which will lead to additional secondary brain damage. It’s called brain engagement.” explains Professor Patrick Mertens. These compressions in the cranial box can affect vital centers of cardiac, vascular or respiratory regulation. “This can then cause paralysis, hemiplegia, as well as disturbances of consciousness that can sometimes go as far as coma”, says Professor Mertens. If the cardio-respiratory centers are affected, cardio-respiratory arrest may occur, leading to death.
In terms of vision, there is a very real risk of major problems, even blindness. “Retinal edema due to stagnation is often observed. If it continues, the sight is in danger”notes Professor Patrick Mertens.
After a complete clinical examination, the diagnosis can be made from various imaging examinations (MRI, scanner). The intracranial pressure reading (ICP) can be measured in different ways. “In the most serious cases, we can insert a small sensor to measure the pressure when the patient is in intensive care”illustrates the doctor.
As this is an emergency reason, this medical situation requires specific care.
The treatment of the cause represents the first therapeutic response (evacuation of a hematoma, excision of a tumour, derivation of hydrocephalus, etc.). In a second step, a symptomatic treatment, generally based on diuretics and analgesics, will be put in place. If the cause of hypertension is thrombosis, anticoagulant therapy will be prescribed. “It may also be necessary to make infusions of diuretics or to set up a treatment based on corticosteroids in order to reduce the edematous element.explains Professor Patrick Mertens.
In the event of treatment failure or insufficient results, the patient can then be transferred to intensive care and sedated in order to cause a reduction in intracranial pressure. In the most delicate situations, a surgical intervention will be scheduled. “Finally, in the most serious cases, a craniectomy, an intervention which consists of cutting out a bony part of the cranial box in order to reduce the pressure inside it, may be considered in certain situations.adds Professor Patrick Mertens.