Locked In
Locked-in syndrome (LIS), also known as pseudocoma, is a condition in which a patient is aware but cannot move or communicate verbally due to complete paralysis of nearly all voluntary muscles in the body except for vertical eye movements and blinking. The individual is conscious and sufficiently intact cognitively to be able to communicate with eye movements.[3] Electroencephalography results are normal in locked-in syndrome.Total locked-in syndrome, or completely locked-in state (CLIS), is a version of locked-in syndrome wherein the eyes are paralyzed as well.[4] Fred Plum and Jerome B. Posner coined the term for this disorder in 1966.[5][6]
Locked In
Locked-in syndrome is usually characterized by quadriplegia (loss of limb function) and the inability to speak in otherwise cognitively intact individuals. Those with locked-in syndrome may be able to communicate with others through coded messages by blinking or moving their eyes, which are often not affected by the paralysis. The symptoms are similar to those of sleep paralysis. Patients who have locked-in syndrome are conscious and aware, with no loss of cognitive function. They can sometimes retain proprioception and sensation throughout their bodies. Some patients may have the ability to move certain facial muscles, and most often some or all of the extraocular muscles. Individuals with the syndrome lack coordination between breathing and voice.[7] This prevents them from producing voluntary sounds, though the vocal cords themselves may not be paralysed.[7]
Unlike persistent vegetative state, in which the upper portions of the brain are damaged and the lower portions are spared, locked-in syndrome is essentially the opposite, caused by damage to specific portions of the lower brain and brainstem, with no damage to the upper brain.[citation needed] Injuries to the pons are the most common cause of locked-in syndrome.
Curare poisoning mimics a total locked-in syndrome by causing paralysis of all voluntarily controlled skeletal muscles.[10] The respiratory muscles are also paralyzed, but the victim can be kept alive by artificial respiration.
Brain imaging may provide additional indicators of locked-in syndrome, as brain imaging provides clues as to whether or not brain function has been lost. Additionally, an EEG can allow the observation of sleep-wake patterns indicating that the patient is not unconscious but simply unable to move.[12]
It is extremely rare for any significant motor function to return, with the majority of locked-in syndrome patients never regaining motor control. However, some people with the condition continue to live for extended periods of time,[14][15] while in exceptional cases, like that of Kerry Pink,[16] Gareth Shepherd,[17] Jacob Haendel,[18] Kate Allatt,[19] and Jessica Wegbrans,[20] a near-full recovery may be achieved with intensive physical therapy.
Locked-in syndrome is a rare neurological disorder in which there is complete paralysis of all voluntary muscles except for the ones that control the movements of the eyes. Individuals with locked-in syndrome are conscious and awake, but have no ability to produce movements (outside of eye movement) or to speak (aphonia). Cognitive function is usually unaffected. Communication is possible through eye movements or blinking. Locked-in syndrome is caused by damaged to the pons, a part of the brainstem that contains nerve fibers that relay information to other areas of the brain.
The first description of the locked-in syndrome can be found in The Count of Monte Cristo authored by Alexandre Dumas. To describe a patient with a locked-in syndrome, the author used the following words:
Individuals with locked-in syndrome classically cannot consciously or voluntarily chew, swallow, breathe, speak, or produce any movements other than those involving the eyes or eyelids. Some affected individuals can move their eyes up and down (vertically), but not side-to-side (horizontally). Affected individuals are bedridden and completely reliant on caregivers. Despite physical paralysis, cognitive function is unaffected.
Individuals with locked-in syndrome are fully alert and aware of their environment. They can hear, see and have preserved sleep-wake cycles. Affected individuals can communicate through purposeful movements of their eyes or blinking or both. They can comprehend people talking or reading to them.
Clinical formsThe locked-in syndrome may be classified in three different clinical forms, according to the traditional classification of Bauer. This classification is based on the amount of motor outputs, which are preserved in the patients. It talks about a pure form when the patient loses the control of all body movements with the exception of blinking and vertical eye movements; an incomplete form when some voluntary movements other than eye movements are preserved and a total form when a complete loss of motor function occurs. The last condition is particularly dramatic as the patients are completely unable to interact with the environment and to express their needs and thoughts.
Quality of life Although the locked-in syndrome appears as the most dramatic form of motor disability one can imagine, some scientific reports indicate that the quality of life of patients is not so poor as expected. A recent survey investigated the self-reported quality of life of chronic patients with locked-in syndrome and concluded that many patients have a happy and meaningful life, especially when proper social services help patients to have a normal role at home as well as in the community.
Additional symptoms under investigationPatients with locked-in syndrome are traditionally considered cognitively intact as all the cerebral structures with the exception of the ventral portion of the pons of the brain are apparently preserved. However, recent evidence suggests that the patients can develop some non-motor symptoms including motor imagery defects, pathological laughter and crying, and difficulties in the recognition of some facial expressions. The interruption of the cortico-ponto-cerebellar pathways, by means of the the same lesion causing the locked-in syndrome, may be responsible for the appearance of these clinical manifestations. However, these symptoms are not detected in all affected individuals and are currently under further investigation. The recognition of motor imagery defects deserves special attention because these symptoms, whenever present, may interfere with the success of rehabilitation strategies.
Locked-in syndrome is a rare neurological disorder that affects males and females in equal numbers. Locked-in syndrome can affect individuals of all ages including children, but most often is seen in adults who are more at risk for brain stroke and bleeding. Because cases of locked-in syndrome may go unrecognized or misdiagnosed, it is difficult to determine the actual number of individuals who have had the disorder in the general population.
A variety of conditions can cause symptoms or a clinical picture that is similar to locked-in syndrome. These disorders or conditions include Guillain-Barre syndrome, myasthenia gravis, poliomyelitis, polyneuritis or bilateral brainstem tumors. Locked-in syndrome can be mistaken for a vegetative state that may occur secondary to trauma or a variety of different conditions, especially if affected individuals have visual or hearing loss making the diagnosis more difficult.
A diagnosis of locked-in syndrome is usually made clinically. A variety of tests may be performed to rule out other conditions. Such tests include magnetic resonance imaging (MRI), which shows the damage to the pons, and magnetic resonance angiography, which can show the blood clot in the arteries of the brainstem. These tests can also rule out damage elsewhere in the brain.
Recent studies and articles in the medical literature have noted that despite significant motor disability affected individuals can retain a good quality of life. In addition, quality of life is unrelated to the degree of physical impairment. With advances in care and assistive technologies, individuals with locked-in syndrome can become productive members of society.
JOURNAL ARTICLESBruno MA, Bernheim JL, Ledoux D, Pellas F, Demertzi A, Laureys S. A survey on self-assessed well-being in a cohort of chronic locked-in syndrome patients: happy majority, miserable minority. BMJ Open 2011;1:e000039.
Babiloni C, Pistoia F, Sarà M, Vecchio F, Buffo P, Conson M, Onorati P, Albertini G, Rossini PM. Resting state eyes-closed cortical rhythms in patients with locked-in-syndrome: An EEG study. Clin Neurophysiol 2010;121:1816-24.
Pistoia F, Conson M, Trojano L, Grossi D, Ponari M, Colonnese C, Pistoia ML, Carducci F, Sarà M. Impaired conscious recognition of negative facial expressions in patients with locked-in syndrome. J Neurosci 2010;30:7838-44.
The locked-in syndrome (pseudocoma) describes patients who are awake and conscious but selectively deefferented, i.e., have no means of producing speech, limb or facial movements. Acute ventral pontine lesions are its most common cause. People with such brainstem lesions often remain comatose for some days or weeks, needing artificial respiration and then gradually wake up, but remaining paralyzed and voiceless, superficially resembling patients in a vegetative state or akinetic mutism. In acute locked-in syndrome (LIS), eye-coded communication and evaluation of cognitive and emotional functioning is very limited because vigilance is fluctuating and eye movements may be inconsistent, very small, and easily exhausted. It has been shown that more than half of the time it is the family and not the physician who first realized that the patient was aware. Distressingly, recent studies reported that the diagnosis of LIS on average takes over 2.5 months. In some cases it took 4-6 years before aware and sensitive patients, locked in an immobile body, were recognized as being conscious. Once a LIS patient becomes medically stable, and given appropriate medical care, life expectancy increases to several decades. Even if the chances of good motor recovery are very limited, existing eye-controlled, computer-based communication technology currently allow the patient to control his environment, use a word processor coupled to a speech synthesizer, and access the worldwide net. Healthy individuals and medical professionals sometimes assume that the quality of life of an LIS patient is so poor that it is not worth living. On the contrary, chronic LIS patients typically self-report meaningful quality of life and their demand for euthanasia is surprisingly infrequent. Biased clinicians might provide less aggressive medical treatment and influence the family in inappropriate ways. It is important to stress that only the medically stabilized, informed LIS patient is competent to consent to or refuse life-sustaining treatment. Patients suffering from LIS should not be denied the right to die - and to die with dignity - but also, and more importantly, they should not be denied the right to live - and to live with dignity and the best possible revalidation, and pain and symptom management. In our opinion, there is an urgent need for a renewed ethical and medicolegal framework for our care of locked-in patients. 041b061a72