Locked-In Syndrome

Locked-in syndrome (LiS) is a rare neurological disorder characterized by paralysis of voluntary muscles, except for those that control your vertical eye (up and down) movements. People with locked-in syndrome are conscious, alert and have their usual cognitive abilities (thinking and reasoning), but they’re unable to show facial expressions, speak or move.

Causes #

• Infection in certain portions of your brain.

• Tumors or masses on your pons or brainstem.

• Demyelination, which is the loss of the protective insulation (myelin) that surrounds nerve cells.

• Certain conditions, such as amyotrophic lateral sclerosis (ALS) and Guillain-Barre syndrome.

• Trauma (injury) to your pons.

• Substance misuse.

Types #

The classical form #

In this type of LiS, you have total immobility (lack of voluntary movement) but can move your eyes vertically (up and down), blink and maintain your usual cognitive abilities. You can also hear.

The incomplete form #

This type of LiS is just like the classical form except you can have some sensation and movement functions in certain areas of your body.

The total immobility form #

In this type of LiS, you have complete body paralysis and loss of eye movement, but you have your normal cognitive abilities. Healthcare providers can tell a person with this form still has cognitive (thinking and reasoning) function by examining cortical function with an electroencephalogram (EEG), a test that measures brain waves.

Symptoms #

Most people with locked-in syndrome cannot consciously or voluntarily:

• Chew.

• Swallow.

• Speak.

• Make facial expressions.

• Produce any body movements below their eyes.

Most people with locked-in syndrome can:

• Move their eyes up and down (vertically) but not side to side (horizontally, or laterally).

• Blink.

All people with locked-in syndrome can:

• Hear.

• Comprehend people talking or reading to them.

• Think and reason as they did before having locked-in syndrome.

• Have sleep-wake cycles.

Diagnosis #

Magnetic resonance imaging (MRI) scan or computed tomography (CT) scan #

An MRI or CT scan can show if you have damage to your pons and/or other portions of your brain.

Cerebral angiography #

This test can reveal if you have a blood clot in the arteries of your brainstem or somewhere else in your brain.

Electroencephalogram (EEG) #

This test measures the electrical activity of your brain. It can help healthcare providers determine if you’re experiencing normal brain activity and sleep-wake cycles, which distinguishes LiS from other conditions.

Evoked potentials #

These are tests that measure the electrical activity in certain areas of your brain and spinal cord in response to stimulation, such as pain, auditory or visual stimulation. Healthcare providers use these tests to assess the damaged responses in your brainstem and the preserved responses in your brain.

Electromyography #

This test measures how well your muscles and nerves work. Healthcare providers may use this test to rule out damage to your muscles and nerves.

Blood tests #

A metabolic panel, particularly checking blood sodium levels, can help determine if pontine myelinolysis is the cause.

Cerebrospinal fluid (CSF) examination #

This test can help determine if an infection or autoimmune condition is causing your symptoms.

Treatment #

Supportive therapy #

Supportive therapy for breathing and feeding is very important, especially early on. People with locked-in syndrome (LiS) often need an artificial aid for breathing and will have a tracheotomy (a tube going in their airway through a small hole in their throat).

Because eating and drinking using your mouth isn’t safe with LiS, people with LiS usually have a small tube inserted in their stomach called a gastrostomy tube (G-tube) to receive food and water.

Other supportive therapies include:

• Preventing complications due to immobilization, such as pneumonia, urinary tract infections (UTIs) and thrombosis.

• Preventing pressure injuries (bedsores).

• Providing physical therapy to prevent limb contractures (lack of range of motion due to joint, muscle or soft tissue limitations).

• Providing physical therapy for rehabilitating the small voluntary movements that remain or recover, if any.

Communication training #

• Speech therapists can help people with locked-in syndrome (LiS) communicate more clearly with eye movements and blinking.

• The method of communication is unique to each person.

• For example, looking up could mean yes and looking down could mean no or vice versa. People with LiS can also form words and sentences by signaling different letters in the alphabet while someone else verbally lists each letter.