Also known as pseudocoma, locked-in syndrome (LIS) is characterized by being conscious but without the ability to make enough movements to produce speech, limb, or facial movements. However, since they are conscious, the people who suffer from it can hear and make vertical eye movements and may be able to communicate by using them. Such patients often remain comatose for some days or weeks, needing artificial respiration and then gradually wake up. Unfortunately, even after waking up, they remain paralyzed and voiceless, superficially resembling patients in a vegetative state or akinetic mutism.1
Though not commonly known and often confused with other conditions like coma, locked-in syndrome got some attention from the French film The Diving Bell and the Butterfly. It was based on the real-life story of ‘Elle’ editor Jean-Dominique Bauby who suffered a stroke and locked-in syndrome.2
Not surprisingly, a study showed that brain waves changed in locked-in syndrome (LIS) patients when they heard their own name. This is because, their cognitive functions, and notably their linguistic comprehension, remained preserved even when suffering from the syndrome.3
There are three broad categories of this condition depending on varying degrees of mobility.
- The classic locked-in syndrome involves paralysis and loss of speech but with preserved consciousness and vertical eye movement.
- The incomplete locked-in syndrome is the same as classic but with remnants of voluntary movement other than vertical eye movement.
- Finally, total locked-in syndrome signifies total immobility and inability to communicate, but with full consciousness.4
What Causes The Syndrome?
Acute ventral pontine lesions are the most common among locked-in syndrome causes. This basically entails damage to a specific part of the brain stem known as the pons, which contains important neuronal pathways running between the cerebrum, spinal cord, and cerebellum. This interruption of all the motor fibers running from the brain via the spinal cord to the body’s muscles results in the inability to speak or move any of the muscle groups.5
Damage to the pons mostly arises from tissue loss due to lack of blood flow. This means one can experience locked-in syndrome after stroke, an infarct, or blood clots. It can also happen due to bleeding (hemorrhage). In few cases, it can also be caused by trauma. Other causes of the locked-in syndrome include infection in certain parts of the brain, tumors, loss of the protective insulation that surrounds nerve cells and inflammation of the nerves. There is also a link between Amyotrophic Lateral Sclerosis (ALS) and locked-in syndrome.6
There is also a link between basilar artery stroke and locked in syndrome and it could be a major cause of the disorder. The basilar artery is one of the main arteries that supplies the brain with oxygen-rich blood. If this artery suffers in the stroke or has a clot, it can typically lead to LIS.7
How Do You Know It’s Locked-In Syndrome?
Locked-in syndrome can affect anybody of any gender or age. But it is most often seen in adults who are at risk for brain stroke and bleeding. A patient of locked-in syndrome is bedridden and cannot consciously or voluntarily chew, swallow, breathe, speak, or produce any movements other than those involving the eyes or eyelids. For some patients with locked-in syndrome, communication is a tad better as they can move their eyes up and down (vertically), but not side-to-side (horizontally).8
Locked-In Syndrome Prognosis
Locked-in syndrome diagnosis can take quite a while. Studies reveal that the diagnosis of LIS on average takes over 2.5 months. More than half of the time it is the family and not the physician who first realized that the patient was actually conscious. In some locked-in syndrome cases, it took as many as 4-6 years before aware and sensitive patients, locked in an immobile body, were recognized as being conscious.9
Locked-in syndrome diagnosis can also be complicated because some patients emerge from the coma only to fall into a locked-in state after a variable delay.10
How Can It Be Treated Or Managed?
Can you recover from locked-in syndrome? While there is no cure for locked-in syndrome, there is hope for patients suffering from this rare neurological disorder.
It is often assumed that the quality of life for LIS patients is too poor to be worth living. But in this day and age of technology and medical innovation, that is not always the case. After diagnosis and once the patient becomes medically stable, locked-in syndrome life expectancy can increase to several decades with appropriate medical care. Even if the chances of good motor recovery may be very limited, existing eye-controlled, computer-based communication technology currently allows the patient to control his environment. They can use a word processor synced to a speech synthesizer and even access the worldwide net.11
But according to researchers at the Heart and Stroke Foundation of Canada, most LIS patients have a strong will to live. Through a 20-year study, they showed that 25 patients with varying degrees of minimal motor skills, could enhance their independence with assistance from technology. Though these patients are practically immobile, they are sometimes left with the ability to make a one- or two-degree movement of the head, a twitch of a finger or toe, or an eye movement. Using these movements, they were given the training to do things such as use a wheelchair through head movements. Such locked-in syndrome stories are enough to provide hope to patients and families.12
There may not be many locked-in syndrome treatment options, but there are plenty of ways to manage the condition. Chances of motor recovery in locked-in syndrome are rare but a therapy called functional neuromuscular stimulation uses electrodes to stimulate muscle reflexes may help activate some paralyzed muscles.13
Some Survivor Stories
Though extremely rare, some patients have experienced partial or total recovery from locked-in syndrome. Sheffield-based Kate Allatt’s brush with locked-in syndrome left her with only eye movements after she suffered bouts of migraines followed by a stroke. The eye movements were followed by tiny thumb movements after eight weeks. Encouraged by her son, she started trying to speak and was successful at that too. Eight months later, Kate walked out of the ward and back to her home.
Another one of locked-in syndrome recovery stories is that of a famous English footballer. Gary Parkinson’s locked-in syndrome was diagnosed in 2010 when he suffered a brain stem stroke and he was able to go home after a little more than two years in the hospital. Though he is still paralyzed and requires 24-hour care, he manages to communicate by blinking and with the help of technology.
|↑1, ↑9, ↑11||Laureys, Steven, Frédéric Pellas, Philippe Van Eeckhout, Sofiane Ghorbel, Caroline Schnakers, Fabien Perrin, Jacques Berre et al. “The locked-in syndrome: what is it like to be conscious but paralyzed and voiceless?.” Progress in brain research 150 (2005): 495-611.|
|↑2, ↑12||Heart and Stroke Foundation of Canada. “Unlocking a brighter future for locked-in syndrome.” ScienceDaily.|
|↑3||Perrin, Fabien, Caroline Schnakers, Manuel Schabus, Christian Degueldre, Serge Goldman, Serge Brédart, Marie-Elisabeth Faymonville et al. “Brain response to one’s own name in vegetative state, minimally conscious state, and locked-in syndrome.” Archives of Neurology 63, no. 4 (2006): 562-569.|
|↑4, ↑10||Smith, Eimear, and Mark Delargy. “Locked-in syndrome.” BMJ: British Medical Journal 330, no. 7488 (2005): 406.|
|↑5, ↑6, ↑8||Locked In Syndrome. NORD.|
|↑7||Khanna, Kunal, Ajit Verma, and Bella Richard. ““The locked-in syndrome”: Can it be unlocked?.” Journal of Clinical Gerontology and Geriatrics 2, no. 4 (2011): 96-99.|
|↑13||Locked-in Syndrome. NIH.|