Weber Syndrome: Causes, Symptoms & Treatment

Weber syndrome is a form of brainstem syndrome. It often results from an ischemic stroke due to thromboembolism. Typical consequences include hemiplegia, impaired ocular motor function, and other neurologic damage.

What is Weber syndrome?

Weber syndrome is one of the brainstem syndromes, all of which result from damage to the brain area of the same name. Physician David Weber was the first to describe the condition, which is also known as midbrain syndrome. Weber syndrome is characterized by damage to the substantia nigra in the midbrain and interruption of certain nerve pathways. The tractus corticopontinus, which connects to the bridge and cerebral cortex, the oculomotor nerve, which controls eye movements, and the pyramidal tract, which transmits motor signals to the body, are particularly affected. The substantia nigra is a core area in the midbrain that has numerous connections to other brain areas. These include, for example, the striatum, thalamus, globus pallidus, nucleus subthalamicus, and cerebral cortex. The substantia nigra also plays an important role in its function within the extrapyramidal motor system. Like the pyramidal tract, this system controls movements.

Causes

Several causes may underlie Weber syndrome. In the majority of cases, the condition results from an ischemic stroke, in which one or more blood vessels leading to the brain become occluded. As a result, the cells behind the occlusion receive little or no oxygen and nutrients, eventually causing them to die. Because the brain has very little ability to form new nerve cells, it cannot replace the dead cells: The brain is irreversibly damaged. The occlusion of various blood vessels may contribute to the development of Weber syndrome. In the vertebral artery, blood flows not only to the brain, but also to the dura mater and the spinal cord. The basilar artery represents one of its branches, which also divides into different branches. One of these, the posterior cerebral artery, can also cause Weber syndrome if it becomes blocked. Regardless of the blood vessel involved, the blockage often results from blood clots. Deposits in the blood vessels can form thrombi, which, moreover, often break loose and become lodged at narrow points or in finer blood vessels. Such emboli can also be based on fat droplets that obstruct the blood vessel.

Symptoms, complaints, and signs

On the side of the brain damage (ipsilateral), Weber syndrome typically results in oculomotor palsy: the oculomotor nerve is interrupted and therefore can no longer transmit nerve signals to the innervated eye muscles. In complete oculomotor palsy, the ipsilateral eye droops, with gaze directed outward. Visual disturbances include forced pupillary dilation (mydriasis), drooping of the eyelid (ptosis), impaired pupillary response, and accommodative dysfunction. Two subtypes are possible in partial oculomotor palsy: internal and external palsy. The former manifests as mydriasis and accommodative dysfunction, whereas in external palsy, the affected eye is rotated downward and outward. Hemiparesis on the side opposite the brain damage (contralateral) is also one of the characteristic symptoms of Weber syndrome. Depending on how severely the brain is damaged, the paralysis can take different forms. It often occurs as spastic paralysis and is accompanied by dystaxia. Other symptoms depend on the nerves affected at the midbrain base.

Diagnosis and course of the disease

As part of the diagnostic process, physicians use imaging techniques, such as computed tomography (CT) or magnetic resonance imaging (MRI). Both allow the affected tissue to be precisely located and the extent of damage to be assessed. Previously performed neurological tests can in many cases already provide initial clues about the nature of the disease. In addition, depending on the cause, the attending physician clarifies whether other organs may be affected or at risk.

Complications

Sturge-Weber syndrome favors malformations in the facial region. Affected individuals suffer from severe aesthetic losses, resulting in psychological discomfort.Inferiority complexes occur frequently in patients and self-esteem declines rapidly. At a young age, the suffering is particularly high, because many patients become victims of bullying. Furthermore, the syndrome entails reduced sensitivity: numbness, indefinable pain and a tingling and burning sensation that cannot be localized aggravate the suffering. This is further complicated by paralysis of various parts of the body. Cataracts often form in association with Sturge-Weber syndrome and the lens of the eye becomes significantly clouded. A strong sensitivity to light is also a sign that the affected person suffers from a cataract. Glaucoma often occurs, which increases eye pressure to the point that the patient may go blind. Mental retardation and developmental delays are also not uncommon, although it makes little difference whether Sturge-Weber syndrome is treated or not. Emotional behavior disorders and learning disabilities are also present. Performing physical activities is rarely possible without assistance, which limits the patient’s independence and mobility. Severe headaches are common in Sturge-Weber syndrome and further limit the quality of life of those affected. The blood vessels in the brain show abnormal development, and severe seizures and epilepsy further worsen the health condition.

When should you see a doctor?

The affected person should definitely see a doctor about Weber syndrome. It is a serious disease that must be examined and treated by a doctor in any case. The earlier the disease is detected and treated, the better the further course of the disease usually is. In most cases, aesthetic impairments or malformations of the face indicate Weber syndrome. Likewise, the risk of stroke can increase significantly as a result of the disease. Should a stroke occur, an emergency physician should be called or a hospital visited immediately. Likewise, intellectual impairment of the affected person may indicate this syndrome and must be examined by a medical professional. Due to the tumors in the face, it is not uncommon to experience visual field deficits or very severe headaches. In the first instance, a general practitioner can be consulted for Weber syndrome. Further examination is usually performed in a hospital. Since the syndrome can lead to severe psychological upsets or depression, psychological treatment should also be carried out in any case. Possibly, the life expectancy of the affected person is also reduced by this disease.

Treatment and therapy

As a first therapeutic measure, physicians provide immediate care to the patient. In addition, an imaging procedure indicates whether intravenous thrombolysis or other immediate intervention is possible. In some cases, this procedure allows the occlusion of the blood vessel to be removed shortly after an ischemic stroke, thereby preventing the death of further tissue. However, numerous factors influence its success, and there is a risk that intravenous thrombolysis may cause bleeding. Intra-arterial lysis with a catheter (catheter intervention) may also be considered. If the cause of Weber syndrome is not a blocked blood vessel but bleeding, surgical interventions are an option to help relieve tissue pressure. After an ischemic stroke, about 40 percent of those affected die in the first year. In the long term, patients undergo extensive rehabilitation that includes occupational and physical therapy, speech therapy, and (neuro)psychological and psychiatric treatments. The aim of these measures is to maintain the patient’s independence and remaining abilities as far as possible. In some cases, brain cells from other areas that are still intact can take over the tasks of the dead cells if the therapy actively stimulates and promotes them. Long-term treatment also includes prevention of further strokes.

Prevention

Prevention of Weber syndrome is essentially the same as general stroke prevention, since one is the cause of brain damage in most cases. In this context, treatment of other conditions such as diabetes mellitus, dyslipidemia, elevated blood pressure, and others is especially crucial.Lifestyle factors that each person can influence include alcohol consumption, smoking habits, diet and exercise. Avoiding stress and obesity can also prevent strokes.

Follow-up

There are usually limited and also few measures of direct aftercare available to the affected person with Weber syndrome, so the affected person should see a doctor very early in this disease. The earlier a doctor is contacted, the better the further course of this disease usually is. This is also a congenital disease, so that it cannot be completely cured. For this reason, the affected person should also have a genetic examination and counseling if he/she wishes to have children, in order to prevent the recurrence of Weber syndrome in the descendants. As a rule, various surgical interventions are necessary to properly and permanently limit the symptoms. In any case, the affected person should rest and take it easy after such an operation, and no strenuous or stressful activities should be performed. Likewise, with this disease, the support and care of one’s family is also very important. This can also prevent psychological upsets and depression. The further course of the syndrome depends very much on the exact manifestation of the disease, and in some cases the life expectancy of the affected person is also reduced.

What you can do yourself

If Weber syndrome is suspected, the first step is to consult a physician. The rare condition occurs as a result of severe brain disorders, which is why a speedy clarification is necessary. It is best to consult a medical professional promptly after the first typical symptoms appear. After the diagnosis, an individual therapy can be worked out depending on the symptoms, which can be supported by the affected person and their relatives. Physiotherapy can be supported at home by independent training. Endurance sports and stretching are important, whereby the exact measures depend on the respective symptoms. The training plan should be drawn up together with the physiotherapist in charge. Weber syndrome can lead to a wide variety of secondary diseases. For example, epileptic seizures can occur. The relatives and the affected person himself must take the necessary measures to minimize the risk of a fall or injury. The tissue damage may also lead to motor disturbances in some circumstances, which in turn are treated by comprehensive physiotherapy. Self-help measures must be regularly adapted to the varying course of the disease in order to continue to achieve an improvement in health.