Cerebellar Ataxia

Cerebellar ataxia is a condition that affects a part of the brain called the cerebellum, causing problems with coordination, balance, and movement that can make everyday tasks challenging.

Table of contents

• What is cerebellar ataxia?
• Associated anatomy
• Symptoms
• Causes
• Duration and outlook
• Diagnosis
• Treatment

What is cerebellar ataxia?

Cerebellar ataxia is a form of ataxia (loss of muscle coordination) that originates from problems in the cerebellum, a part of the brain located at the back of the head, below the larger brain and close to the brainstem.^[1] The cerebellum is responsible for coordinating muscle movements, controlling balance, regulating speech, and managing eye movements.^[2]

When the cerebellum is damaged or not working properly, it leads to difficulties controlling voluntary movements. People with cerebellar ataxia often move in an uncertain, awkward, or clumsy way because their brain cannot properly coordinate how their muscles work together.^[2]

Cerebellar ataxia describes a set of symptoms that happen after losing muscle control due to cerebellar dysfunction. It can occur as a symptom of another medical condition or happen on its own.^[4] Problems appear on the same side of the body as the damage in the cerebellum, which doctors call ipsilateral effects.^[6]

Associated anatomy

• Cerebellum
• Brainstem
• Spinal cord

Symptoms

Cerebellar ataxia can cause a wide range of symptoms related to movement, balance, and coordination. The symptoms can develop over time or start suddenly, depending on the underlying cause.^[1]

Common symptoms include:^[1][8][14]

• Walking unsteadily or with feet set wide apart
• Poor balance and frequent falls
• Loss of coordination in the arms and legs
• Trouble with fine motor tasks such as eating, writing, or buttoning a shirt
• Slurred or slow speech (called dysarthria)
• Difficulty swallowing
• Back-and-forth eye movements that cannot be controlled (called nystagmus)
• Problems with eye movement and vision
• Hand tremors, especially when reaching for objects
• Body swaying when sitting

When a person is sitting, their body may move side-to-side or back-to-front, then quickly return to an upright position. When reaching for an object, the hand may sway back and forth.^[3]

The symptoms of cerebellar ataxia can worsen over time, especially without treatment. The exact symptoms depend on the type of cerebellar ataxia and which parts of the cerebellum are affected.^[8]

Causes

Cerebellar ataxia has many different causes. These can be grouped into three main categories: acquired, hereditary, and sporadic.^[2][4]

Acquired cerebellar ataxia develops as a result of damage or disease that occurs during a person’s lifetime. Some causes are temporary or reversible. Conditions and circumstances that can cause acquired cerebellar ataxia include:^[2][3][5]

• Stroke affecting the cerebellum
• Head injuries and traumatic brain damage
• Brain tumors
• Bleeding into the cerebellum
• Infections caused by viruses or bacteria (including chickenpox, Coxsackie disease, Epstein-Barr virus, and others)
• Multiple sclerosis and other immune system diseases
• Long-term, excessive alcohol consumption
• Vitamin deficiencies (especially vitamin E)
• Exposure to toxins, certain medications, or illicit drugs
• Celiac disease
• Conditions associated with some cancers (called paraneoplastic disorders)

In children, particularly those younger than age 3, acute cerebellar ataxia may occur several days or weeks after a viral illness.^[3][8] This type is thought to be caused either by the infection itself or by the body’s immune system reaction to the infection.^[8]

Hereditary cerebellar ataxia is caused by faulty genes passed down from parents to children. These genetic conditions can be inherited in different patterns. Some require inheriting two copies of the affected gene (one from each parent), while others need only one copy from either parent. Examples include Friedreich’s ataxia and spinocerebellar ataxia.^[4][5]

Gluten ataxia, an autoimmune condition triggered by gluten, accounts for 40% of all sporadic idiopathic ataxias (ataxias with no clear cause) and 15% of all ataxias.^[6]

Sporadic or idiopathic cerebellar ataxia happens because of spontaneous genetic changes that occur randomly before birth or during adulthood. These gene changes are not inherited from parents. In many cases, the cerebellum progressively deteriorates over time for reasons that remain unclear.^[4][5]

Duration and outlook

The duration and outlook for cerebellar ataxia varies greatly depending on the underlying cause.^[5]

Acute cerebellar ataxia caused by a recent viral infection in children usually improves on its own. Most people make a full recovery without treatment within a few months, though some children may experience symptoms for a longer period.^[3][8] Acute cerebellar ataxia almost always goes away within 2 weeks.^[8]

Cerebellar ataxia caused by vitamin deficiencies or toxin exposure may improve when the underlying problem is addressed.^[8]

For hereditary and progressive degenerative forms, most cases will worsen gradually over many years. Some types may remain relatively stable or even improve with time, but many will progressively deteriorate.^[5] Life expectancy can be affected by hereditary forms, though some people live well into their 50s, 60s, or beyond. In severe cases, the condition can be fatal in childhood or early adulthood.^[5]

Strokes, bleeding, or infections affecting the cerebellum may cause permanent symptoms.^[3]

Diagnosis

Diagnosing cerebellar ataxia involves several steps. A healthcare provider will first ask questions about medical history, family history, recent illnesses, and symptoms. This is followed by a physical examination and a neurological exam to check vision, balance, coordination, reflexes, and identify which areas of the nervous system are most affected.^[3][9]

Several tests may be ordered to confirm the diagnosis and rule out other conditions:^[3][8][9]

• Blood tests to look for vitamin deficiencies, toxins, infections, or treatable causes
• Urine tests to detect certain toxins
• MRI (magnetic resonance imaging) or CT (computed tomography) scan of the brain to look at the cerebellum and check for shrinkage, tumors, bleeding, blood clots, or other abnormalities
• Spinal tap (lumbar puncture) to test the cerebrospinal fluid for infections or inflammation
• Genetic testing to identify gene changes that may be causing hereditary ataxia
• EMG (electromyography) to assess nerve and muscle function

An MRI can sometimes show shrinkage of the cerebellum and other brain structures in people with ataxia, and may reveal treatable findings.^[9] Genetic tests are available for many, but not all, hereditary ataxias.^[9]

Treatment

Treatment for cerebellar ataxia depends on the underlying cause. In some cases, treating the condition that caused the ataxia can help improve or stop symptoms from worsening. However, in most cases, this is not possible, and treatment focuses on relieving symptoms and improving quality of life.^[5][9]

Treating the underlying cause: If cerebellar ataxia is caused by a treatable condition, addressing it may help. For example, treating vitamin deficiencies, celiac disease, or stopping alcohol consumption may improve symptoms. If bleeding is the cause, surgery may be needed. For stroke, blood-thinning medication or removing a blood clot may be necessary. Infections may need antibiotics or antivirals, and inflammation may require corticosteroids.^[3][9]

Acute cerebellar ataxia caused by viral infection may not need treatment and usually resolves on its own.^[3]

For Friedreich’s ataxia, an oral medicine called omaveloxolone (Skyclarys) has been approved for treatment in adults and teenagers.^[9]

Supportive therapies and symptom management: Most people with cerebellar ataxia will be cared for by a team of healthcare professionals who create a personalized care plan addressing physical, social, and psychological needs.^[11] Treatment options include:^[1][5][11]

• Physical therapy to maintain arm and leg use, prevent muscles from weakening or becoming stuck, strengthen muscles, and reduce the risk of falls. Therapists can recommend walking aids and teach exercises to improve movement.
• Occupational therapy to help adapt to mobility loss, learn to use wheelchairs and mobility devices, and make home modifications such as guide rails or stair lifts.
• Speech and language therapy to improve slurred speech and help with swallowing problems. Therapists can suggest posture changes, voice exercises, speaking techniques, and breathing methods. They may also recommend speaking aids or dietary changes for easier swallowing.
• Medications for specific symptoms, such as muscle relaxants (baclofen or tizanidine) for muscle spasms and stiffness, or medications to control bladder problems, eye movements, or tremors.
• Adaptive devices such as walkers, canes, and wheelchairs to help maintain independence.
• Regular exercise to help maintain function and reduce symptoms.

Research shows that rehabilitation with balance and coordination exercises can improve postural abilities in patients with cerebellar ataxia, particularly those with degenerative ataxia or multiple sclerosis. Intensive rehabilitation programs are necessary for improvement.^[6]

Some studies suggest that mild to moderate cerebellar ataxia may be treatable with buspirone, which is thought to increase serotonin levels in the cerebellum.^[6]

If botulinum toxin injections are not effective for muscle problems or bladder issues, they may be given to block signals from the brain to affected muscles. The effects usually last up to 3 months.^[11]