What is Wallenberg Syndrome

Wallenberg syndrome, also known as lateral medullary syndrome, is a rare neurological disorder caused by a stroke in the lateral medulla of the brainstem. It typically presents with a sudden onset of symptoms including vertigo, gait instability, and sensory loss on opposite sides of the body, and it requires urgent medical evaluation.

What causes Wallenberg syndrome?

Wallenberg syndrome occurs when blood flow to the lateral portion of the medulla oblongata is interrupted, usually due to an occlusion of the vertebral artery or the posterior inferior cerebellar artery (PICA). This specific area of the brainstem is responsible for vital autonomic functions, pain and temperature sensation, and coordination. Because the damage is localized to the medulla, Wallenberg syndrome creates a unique "crossed" sensory pattern where the face loses sensation on the same side as the stroke, while the body loses pain and temperature sensation on the opposite side.

What are the primary symptoms of Wallenberg syndrome?

The clinical presentation of Wallenberg syndrome is often dramatic and sudden. Patients frequently experience a constellation of neurological deficits, which can include:

• Vertigo and nausea: Often accompanied by intense nystagmus (involuntary eye movement).


• Ataxia: Severe lack of coordination and balance, making it difficult to walk.


• Dysphagia and hoarseness: Damage to the cranial nerves can make swallowing difficult and change the voice.


• Horner’s syndrome: A drooping eyelid (ptosis) and constricted pupil on the side of the lesion.


• Sensory dissociation: Loss of pain and temperature sensation on the face (ipsilateral) and the body (contralateral).

How common is Wallenberg syndrome?

While exact global prevalence rates are difficult to calculate, Wallenberg syndrome is considered the most common brainstem stroke syndrome. It most frequently affects adults over the age of 50, though it can occur in younger individuals if there is an underlying vertebral artery dissection. There is no significant geographic clustering; however, it is a diagnosis that requires high clinical suspicion in emergency settings.

How does Wallenberg syndrome differ from other strokes?

Unlike many other strokes that cause motor weakness (paralysis), Wallenberg syndrome rarely causes significant limb weakness. Instead, the hallmark of Wallenberg syndrome is the combination of sensory deficits and autonomic dysfunction. At DiseaseMaps.org, 55 people with Wallenberg syndrome have joined our community to share their experiences, highlighting the importance of peer support during the recovery journey.

Next steps

• Seek immediate emergency medical care if you or a loved one experience sudden vertigo, swallowing difficulties, or balance loss.


• Consult a neurologist or neuro-rehabilitation specialist to develop a personalized recovery plan.


• Join the DiseaseMaps.org community to connect with others who have navigated the recovery process from Wallenberg syndrome.

Medical disclaimer: This information is for educational purposes only and does not constitute professional medical advice, diagnosis, or treatment; always seek the advice of your physician with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD)


• Orphanet: Portal for rare diseases and orphan drugs


• National Institute of Neurological Disorders and Stroke (NINDS)


• PubMed: Clinical reviews on Lateral Medullary Syndrome