OVERVIEW

What is Wallenberg syndrome?

It is a type of ischemic stroke, commonly referred to as "cerebral infarction."

It is caused by the occlusion of the "posterior inferior cerebellar artery" or "vertebral artery" in the posterior part of the brain. The dorsolateral region of the upper medulla loses blood supply, leading to functional abnormalities within a short period. As a result, patients experience a series of deficits in movement, sensation, and language. Therefore, Wallenberg syndrome is also known as "lateral medullary syndrome."

Is Wallenberg syndrome common?

Yes. Wallenberg syndrome is the most common posterior circulation ischemic stroke syndrome. In the United States, there are nearly 800,000 acute stroke patients annually, with over 60,000 new cases of Wallenberg syndrome.

SYMPTOMS

What are the manifestations of Wallenberg syndrome?

Due to the abundance of nerve nuclei and fibers in the dorsolateral medulla, the clinical manifestations of Wallenberg syndrome are diverse. Common clinical presentations include:

• Crossed sensory disturbance: The most common clinical manifestation of Wallenberg syndrome. When pain and temperature sensation are diminished on one side of the face, the contralateral trunk also experiences reduced pain and temperature sensation. In affected areas, patients cannot feel pain or distinguish between hot and cold.
• Dizziness: A sensation of spinning or lightheadedness.
• Horner's syndrome: Drooping eyelid, constricted pupil, and reduced sweating on one side of the face.
• Unsteady gait: Difficulty walking, swaying, or stumbling.
• Nausea and vomiting.
• Nystagmus: Involuntary eye movements when focusing.
• Hoarseness.
• Limb incoordination (ataxia): Difficulty performing fine motor tasks, such as buttoning clothes or using chopsticks.
• Difficulty speaking (dysarthria): Inability to articulate words normally.
• Difficulty swallowing (dysphagia): Choking or coughing when drinking water.
• Persistent hiccups.
• Bradycardia: Slow heart rate.

Clinical manifestations may vary among patients depending on the severity and extent of the condition. However, if Wallenberg syndrome is suspected, immediate medical attention is necessary. Informing the doctor of any symptoms the patient experiences can aid in rapid diagnosis.

CAUSES

What causes Wallenberg syndrome?

Wallenberg syndrome is most commonly caused by vascular occlusion due to large artery atherosclerosis, followed by vascular occlusion due to cardiogenic embolism.

Other less common causes include mechanical neck injury, vertebral artery dissection, arterial wall inflammation, aneurysms, arteriovenous malformations, head trauma, metastatic tumors, multiple sclerosis, etc.

What are the controllable risk factors for Wallenberg syndrome?

The risk factors for Wallenberg syndrome are largely consistent with those of ischemic stroke. Controllable risk factors include:

• Hypertension: Weight loss, a low-fat and low-salt diet, and regular exercise can help control blood pressure. If these measures fail, seek medical help promptly.
• High cholesterol: Improve lifestyle and adjust dietary habits.
• Smoking: Smoking is an independent risk factor. Quitting smoking is essential for both personal and others' health.
• Obesity: Weight loss, calorie control, and regular exercise.
• Lack of exercise: Improve lifestyle and ensure weekly physical activity.
• Diabetes: Diabetic patients should control sugar intake, prioritize exercise, and consult a doctor for appropriate medication to manage blood sugar levels if necessary.

What are the uncontrollable risk factors for Wallenberg syndrome?

In addition to controllable risk factors, other uncontrollable factors include:

• History of transient ischemic attacks or stroke.
• Age: Generally, older adults have a higher incidence rate.
• Family history of similar stroke conditions.

If these risk factors are present, greater emphasis should be placed on prevention. For those with underlying conditions, follow medical advice, maintain regular exercise, and avoid emotional agitation.

DIAGNOSIS

How to Quickly Determine if a Patient is Having a Stroke?

Ordinary people cannot professionally determine the specific type of stroke, but they can make a preliminary assessment of whether they or the patient is experiencing a stroke by checking for relevant symptoms and then seeking medical attention. Just remember the English phrase "BE FAST," where each letter represents a key symptom to assess:

Balance: Is there unsteadiness while standing or difficulty walking?
Eyes: Are there vision abnormalities?
Face: Is there facial asymmetry or numbness?
Arms: Is there weakness, numbness, or abnormal sensation in one or both limbs?
Speech: Is speech slurred or difficult?
Time: If any of the above symptoms suddenly appear, call an ambulance immediately. The sooner treatment is received, the better the chances of recovery.

Stroke symptoms typically appear suddenly and progress rapidly within hours or days. For stroke patients, time is life, so quick judgment and prompt medical attention are crucial.

How is Wallenberg Syndrome Diagnosed by Doctors?

Based on the patient's description of symptoms, medical history, and physical examination, doctors can usually suspect or preliminarily diagnose Wallenberg syndrome. To confirm the diagnosis, certain imaging tests are essential, such as:

• Diffusion-weighted MRI (DWI): The best method to confirm infarction in the dorsolateral medulla.
• Angiography: Helps identify the site of vascular occlusion and rule out uncommon causes like vascular malformations or vertebral artery dissection.
• Electrocardiogram (ECG): Helps exclude underlying conditions like atrial fibrillation or acute coronary syndrome.

TREATMENT

What treatments do patients with Wallenberg syndrome need immediately?

For the acute phase treatment of Wallenberg syndrome, the primary goals are to reduce the infarct size and prevent related complications. As with other ischemic strokes, time is critical. The main treatment approaches include:

• Intravenous thrombolysis: After evaluation, recombinant tissue plasminogen activator (rtPA) may be administered within 3–4.5 hours of symptom onset, or urokinase within 6 hours. Close monitoring is required during and for 24 hours after thrombolytic therapy.
• Endovascular intervention: Primarily used for large intracranial vessel occlusion, which can significantly improve prognosis.

What general treatments do Wallenberg syndrome patients also require?

In addition to the above targeted treatments, general supportive care includes:

• Intravenous volume expansion: Avoid hypotonic solutions to reduce the risk of cerebral edema.
• Blood pressure management: Approximately 70% of stroke patients experience elevated blood pressure during the acute phase. Most do not require medication, as blood pressure typically declines within 24 hours.
• Glucose management: Hyperglycemia is common in acute stroke, but blood glucose should ideally be maintained within normal levels.
• Swallowing assessment: Prevent aspiration; nasogastric feeding may be necessary if needed.
• Deep vein thrombosis prophylaxis: High-risk patients may receive prophylactic-dose anticoagulation.
• Temperature control: Antipyretic measures should be taken for patients with a temperature >38°C.
• Antiplatelet therapy: Patients not receiving thrombolysis should start aspirin or clopidogrel within 48 hours. Dual antiplatelet or combined anticoagulant therapy may be required in some cases. Long-term antiplatelet use can serve as stroke prevention.
• Complication prevention: Common post-stroke complications include anxiety, falls, impaired consciousness, stress ulcers, and osteoporosis.

When should rehabilitation begin for Wallenberg syndrome patients?

Rehabilitation should start as early as possible once vital signs are stable and symptoms cease progressing, to maximize functional recovery and minimize complications.

The mode and intensity of rehabilitation should be tailored to the patient’s physical strength, endurance, and cardiopulmonary function. Therefore, physicians must thoroughly assess the patient’s condition to develop an appropriate rehabilitation plan.

DIET & LIFESTYLE

Can patients with Wallenberg syndrome fully recover?

The prognosis for patients with Wallenberg syndrome depends on the size and location of the lesion, as well as the treatment, care, and rehabilitation they receive. Some patients may experience symptom relief within weeks of onset, while others may have persistent symptoms for years or even lifelong disabilities.

Therefore, in addition to early treatment, patients must strictly adhere to their medical plan to maximize recovery chances and achieve a positive outcome. Any concerns about the treatment plan should be discussed with the doctor.

What should patients with Wallenberg syndrome pay attention to in daily life?

Patients should focus on the following lifestyle habits:

1. Diet: Follow a low-salt, low-fat diet, preferably the Mediterranean diet, especially for those with a history of stroke or transient ischemic attack. Hypertensive patients should limit salt intake.
2. Exercise: Engage in moderate-intensity aerobic exercise for at least 10 minutes, four times a week, and high-intensity aerobic exercise for at least 20 minutes, twice a week. Patients with mobility difficulties should consult a physical therapist or rehabilitation specialist for tailored exercise recommendations.
3. Quit smoking: Patients with a history of stroke or transient ischemic attack should quit smoking and avoid secondhand smoke.
4. Personal hygiene: Maintaining hygiene can be challenging due to limited mobility, so patients should establish good habits and may require assistance from family members.
5. Reduce or quit alcohol consumption.
6. Control blood pressure and blood sugar.
7. Avoid emotional agitation.

What should family members of patients do?

• Provide emotional support to help patients build confidence and cope with the disease positively.
• Assist patients with daily activities, including meals, mobility, and personal hygiene, if they have difficulty managing independently.
• Encourage and support patients in adhering to treatment and rehabilitation plans.

PREVENTION

How to Prevent Recurrence for People with a History of Stroke or TIA?

Preventing Wallenberg syndrome or stroke recurrence primarily involves controlling risk factors:

1. Control hypertension: For patients with a history of stroke or transient ischemic attack, blood pressure should be maintained at <130/80 mmHg. Consult a doctor to select appropriate antihypertensive medications.
2. Control cholesterol: Limit fat intake and engage in moderate physical exercise. Aim for LDL levels <70 mg/dl. Consult a doctor for lipid-lowering medications if necessary.
3. Control blood sugar: Diabetic patients should maintain HbA1c <7%. If control is inadequate, consult an endocrinologist for medication adjustments.
4. Medications: For nearly all eligible patients without contraindications, antiplatelet or anticoagulant therapy is recommended for secondary prevention.
5. Surgery: For severe extracranial large vessel stenosis, carotid endarterectomy may be an option.

Combining these approaches can reduce the risk of recurrent stroke by 80%.

How Can the General Public Prevent Stroke?

Adopt a healthier lifestyle, control blood pressure, cholesterol, and blood sugar, exercise regularly, and seek immediate medical attention if symptoms arise.