Brain herniation involves serious health problems and without immediate treatment and follow-up intervention, death or debilitating complications can result.
Definition & Facts
Brain herniation concerns the brain, cerebrospinal fluid, and blood vessels, and involves the abnormal movement of tissues within the brain from their normal positions within the skull due to pressure. It can result in brain damage.
Brain herniation can be either supratentorial and infratenorial. Supratentorial herniations affect brain structures above the tentorial incisure (where the brainstem passes through) and infratentorial affect structures below the tentorial notch. Brain herniation types consist of uncal (related to uncus), central, cingulate (related to cingulate cortex), transcalvarial, upward, and tonsillar.
Symptoms & Complaints
- Fatigue and lethargy
- Respiratory problems or respiratory arrest (not breathing)
- Dilated and non-reactive pupils
- Lack of movement in one eye or both eyes and drooping eyelids
- Reflex losses (blinking, gagging, reaction of pupils of eyes to light)
- Paralysis and abnormal posturing
- Pituitary gland problems
- Loss of consciousness
- Cardiac arrest (lack of pulse) and coma.
- Serious blood pressure fluctuations (hypotension and hypertension)
- Inability to remain alert
- Vertigo (dizziness)
- Afflicted gait (walking)
As with other conditions related to or caused by traumatic brain injuries, many patients with brain herniation are afflicted long-term with cognitive impairment, speech disorders, and language disorders. They may also have a number of physical, psychological, educational and social issues as well as the development of more complicated neurological disorders.
Brain herniation can be caused by anything that brings about swelling to the brain (encephalitis). The condition could be caused by bleeding (hemorrhaging) within the brain itself, brain tumors (metastatic and primary brain tumors), and cerebral contusions from traumatic head injuries.
Other factors that influence brain herniation include bacterial meningitis, brain abscesses, strokes, hydrocephalus (water on the brain), and swelling from radiation therapy. Brain herniation can also occur between areas within the skull that are separated by tough membranes (tentorium cerebelli/falx cerebelli), through the opening at the base of the skull (foramen magnum). It can also result from complications of brain surgery.
Diagnosis & Tests
Diagnosis of brain herniation is based on the medical history of the patient along with the presentation of symptoms that are associated with herniation. A physical examination will be able to detect some of these telltale symptoms such as high blood pressure and slow pulse (bradycardia).
Neurological examinations that test the brain and central nervous system will help to indicate changes that occur with reflexes and nerve functioning. More specialized tests, which take actual pictures of the inside of the skull and brain include cranial magnetic resonance imaging (MRI) and cranial computed tomography (CT) scans which can aid in confirmation of the diagnosis.
Treatment & Therapy
Brain herniation is a life-threatening condition that requires an immediate emergency response. The treatment objective is to save the patient's life. The process almost always entails reducing swelling to the brain as well as pinpointing the exact area of possible herniation for further treatment options.
The patient may require surgery or be given medication intravenously to decrease the swelling and stop any blood leakage. Usually a drain is placed in the brain to remove cerebrospinal fluid (bodily fluid in the brain and spine), and corticosteriods (steroid hormones) may be utilized to reduce swelling. Diuretics are also used to remove bodily fluids and aid in the reduction of pressure within the skull.
Additionally, airway tubes (endotracheal intubation) are inserted to improve breathing rates and decrease carbon dioxide (CO2) blood levels. Blood clots are removed via thrombolysis when they are causing pressure inside the skull and leading to herniation. Further surgery may involve removing a section of skull to allow the brain additional room (decompressive craniectomy).
If the herniation is caused by cancer, chemotherapy and radiation therapy may be utilized to treat the cancer depending on its stage and how far it has spread.
Therapies for brain herniation are rehabilitative as in many cases the condition causes brain damage and a number of challenges to a person's quality of life. Speech therapy, language therapy, physical therapy, and occupational therapy may all be utilized to rehabilitate patients who have lingering disabilities as a result of brain damage.
Multipotential drugs that are used to intervene with the secondary effects of brain injuries are currently under testing and being utilized experimentally. Some of the drugs in current studies include the following:
- Cell cycle inhibitors, which exert powerful neuroprotective effects
- Immunosuppressant drugs that improve the health of damaged neural pathways
- Progesterone (a type of neurosteroid) which has been effectively used to treat stroke, brain injury, and spinal cord injuries
- Statins may also be used
Prevention & Prophylaxis
These injuries, which are usually the result of trauma or a blow to the head can be alleviated through safety programs that stress the use of headgear and helmet devices that cushion the head from injuries that can be incurred through contact sports, motorcycle and bicycle riding, skiing and other physical and thrill-seeking sports.
It is important to seek prompt emergency medical treatment if experiencing symptoms and to pursue follow-up treatment once the emergency has been addressed. Therapies performed by physical therapists, speech pathologists and cognitive rehabilitation therapists for stroke and brain injury patients can be applied to remediate loss of cognitive function, physical disability, and speech impairments.