Incomplete Locked-in Syndrome Research Articles

High Doses of Caffeine-Induced Cerebral Infarction Leading to Partial Locked-In Syndrome in a Young Adult: A Novel Association?

This is a case of a 30-year-old male with no prior medical conditions presented to the emergency department for presumed seizures after ingesting 900 mg of caffeine via pre-workout drinks and pills. Patient was described as having nearly 15 minutes of generalized seizure activity observed by emergency medical service, requiring midazolam. A head computerized tomography (CT) demonstrated a possible thrombus, and further, CT angiography and CT perfusion confirmed a basilar artery occlusion. He was treated with tissue plasminogen activator (tPA) and underwent thrombectomy achieving TICI grade 3 in the left posterior cerebral artery and TICI grade 2b in the superior cerebellar artery. Unfortunately, the patient experienced a hemorrhagic conversion leading to an incomplete locked-in syndrome. This case report suggests a novel association between energy drinks and caffeine supplements as potential etiologies for rapid onset on cerebrovascular incidents.

Demographic, Medical, and Clinical Characteristics of a Population-Based Sample of Patients With Long-lasting Locked-In Syndrome.

Patients with classic locked-in syndrome (LIS), typically caused by ventral pontine stroke, present with quadriplegia, mutism, intact consciousness, and communication skills limited to vertical gazing and/or blinking. Clinical presentations and definitions of LIS differ, especially regarding incomplete LIS. In our study, we explored the functional diversity of LIS, its outcomes, and the complexity of its course along with variations in the location of lesions and their potential significance for outcomes. A national cohort of patients with vascular LIS who remained in the LIS state for at least 6 weeks according to a functional definition of LIS was studied. Demographic, medical, and follow-up data, collected between 2012 and 2022, were obtained from the quality register of the Norwegian National Unit for Rehabilitation of Locked-In Syndrome. Outcomes in verbal communication, motor function, and dependency were evaluated according to criteria for being in or not in the LIS state. The modified Rankin scale and LIS motor recovery scale were applied. Descriptive analysis was performed. The relationship between lesion location and functional outcome was investigated. The sample included 51 patients (median age: 55.7 years, 36 male individuals), 43 of whom had follow-up data. Ischemic stroke was the most common etiology (n = 35). Twenty-three patients had emerged from the LIS state, mostly within 2 years after onset. All but 1 patient achieved some motor improvement, whereas only 3 achieved full motor recovery, and 88% had a persistently high level of dependence. The 3-year survival rate was 87%. Five patients had an isolated pontine lesion, whereas 80% showed various lesions outside the brain stem. Patients who emerged from the LIS state had a significantly lower prevalence of lesions outside the brain stem than patients who remained in the LIS state did. Investigating an unselected population-based sample of patients with vascular LIS offers important insights into the functional diversity of LIS. Although most patients remained severely disabled, even small improvements in function can substantially increase the potential for activity and participation. Additional lesions outside the brain stem seem to be common in long-lasting LIS and might be prognostic for remaining in the LIS state.

Locked-in syndrome revisited

The locked-in syndrome (LiS) is characterized by quadriplegia with preserved vertical eye and eyelid movements and retained cognitive abilities. Subcategorization, aetiologies and the anatomical foundation of LiS are discussed. The damage of different structures in the pons, mesencephalon and thalamus are attributed to symptoms of classical, complete and incomplete LiS and the locked-in plus syndrome, which is characterized by additional impairments of consciousness, making the clinical distinction to other chronic disorders of consciousness at times difficult. Other differential diagnoses are cognitive motor dissociation (CMD) and akinetic mutism. Treatment options are reviewed and an early, interdisciplinary and aggressive approach, including the provision of psychological support and coping strategies is favoured. The establishment of communication is a main goal of rehabilitation. Finally, the quality of life of LiS patients and ethical implications are considered. While patients with LiS report a high quality of life and well-being, medical professionals and caregivers have largely pessimistic perceptions. The negative view on life with LiS must be overthought and the autonomy and dignity of LiS patients prioritized. Knowledge has to be disseminated, diagnostics accelerated and technical support system development promoted. More well-designed research but also more awareness of the needs of LiS patients and their perception as individual persons is needed to enable a life with LiS that is worth living.

Writing Blindly in Incomplete Locked-In Syndrome with A Custom-Made Switch-Operated Voice-Scanning Communicator—A Case Report

Locked-In Syndrome (LIS) is a rare neurological condition in which patients' ability to move, interact, and communicate is impaired despite their being conscious and awake. After assessing the patient's needs, we developed a customized device for an LIS patient, as the commercial augmentative and alternative communication (AAC) devices could not be used. A 51-year-old woman with incomplete LIS for 15 years came to our laboratory seeking a communication tool. After excluding the available AAC devices, a careful evaluation led to the creation of a customized device (hardware + software). Two years later, we assessed the patient's satisfaction with the device. A switch-operated voice-scanning communicator, which the patient could control by residual movement of her thumb without seeing the computer screen, was implemented, together with postural strategies. The user and her family were generally satisfied with the customized device, with a top rating for its effectiveness: it fit well the patient's communication needs. Using customized AAC and strategies provides greater opportunities for patients with LIS to resolve their communication problems. Moreover, listening to the patient's and family's needs can help increase the AAC's potential. The presented switch-operated voice-scanning communicator is available for free on request to the authors.

Conscious While Being Considered in an Unresponsive Wakefulness Syndrome for 20 Years.

Despite recent advances in our understanding of consciousness disorders, accurate diagnosis of severely brain-damaged patients is still a major clinical challenge. We here present the case of a patient who was considered in an unresponsive wakefulness syndrome/vegetative state for 20 years. Repeated standardized behavioral examinations combined to neuroimaging assessments allowed us to show that this patient was in fact fully conscious and was able to functionally communicate. We thus revised the diagnosis into an incomplete locked-in syndrome, notably because the main brain lesion was located in the brainstem. Clinical examinations of severe brain injured patients suffering from serious motor impairment should systematically include repeated standardized behavioral assessments and, when possible, neuroimaging evaluations encompassing magnetic resonance imaging and 18F-fluorodeoxyglucose positron emission tomography.

P012 Unexpected improvement of motor function in a stroke patient following an rTMS treatment for auditory hallucinations: a case report

Introduction Auditory verbal hallucinations (AVHs) are perception-like experiences that occur without an external stimulus. AVHs can occur following a stroke. Repetitive Transcranial Magnetic Stimulation (rTMS) is a tool used to induce brain plasticity in local and remote areas of the brain that may be used for AVHs treatment. Here, we report the case of a patient experiencing AVHs following a stroke treated with rTMS applied to the left temporoparietal junction. Objective To treat AVHs in a post-stroke incomplete locked-in patient with rTMS. Patient and methods Following a stroke event, an MRI revealed bilateral lesions in a 55-year-old male brain (large lesion from the bulbo-pontine junction to the cerebral peduncles, and small lesions in the right cerebellar and the left capsulo-thalamic regions). The patient developed an incomplete locked-in syndrome and he experienced AVHs and delusional melancholia six years after the insult. An antipsychotic treatment was not tolerated well and, consequently, an experimental treatment by rTMS was applied to this patient to ameliorate these symptoms. To this purpose, an inhibitory 1-Hz rTMS protocol was delivered twice per day, with an interval of 1 h and an intensity of 100% of his resting Motor Threshold of the left hemisphere. Each session lasted 20 min and delivered 1200 pulses. In total, 56 rTMS sessions were administered. AVHs and mood were assessed using the Auditory Hallucinations Rating Scale (AHRS), the Beck Depression Inventory (BDI) and the Hospital Anxiety and Depression scale (HAD) before and during the treatment. Results After 26 sessions of the 1-Hz rTMS, the AHRS score was reduced from 29 to 0, indicating the absence of AVHs. A reduction of BDI and HAD scores showed an improvement in mood. In addition, there was an unexpected improvement of motor function in the contralateral hand to the stimulated region. Conclusion Repetitive TMS should be considered as a therapeutic option for AVHs following a stroke. Potential associated motor improvement that stimulation could unfold provides additional value to the use of rTMS such clinical scenario. Further investigations are underway to understand the brain plasticity mechanisms underlying such unexpected motor improvement.

Long-Term Stable Control of Motor-Imagery BCI by a Locked-In User Through Adaptive Assistance

Performance variation is one of the main challenges that BCIs are confronted with, when being used over extended periods of time. Shared control techniques could partially cope with such a problem. In this paper, we propose a taxonomy of shared control approaches used for BCIs and we review some of the recent studies at the light of these approaches. We posit that the level of assistance provided to the BCI user should be adjusted in real time in order to enhance BCI reliability over time. This approach has not been extensively studied in the recent literature on BCIs. In addition, we investigate the effectiveness of providing online adaptive assistance in a motor-imagery BCI for a tetraplegic end-user with an incomplete locked-in syndrome in a longitudinal study lasting 11 months. First, we report a reliable estimation of the BCI performance (in terms of command delivery time) using only a window of 1 s in the beginning of trials (AUC ≈ 0.8 ). Second, we demonstrate how adaptive shared control can exploit the output of the performance estimator to adjust online the level of assistance in a BCI game by regulating its speed. In particular, online adaptive assistance was superior to a fixed condition in terms of success rate ( ). Remarkably, the results exhibited a stable performance over severalmonths without recalibration of the BCI classifier or the performance estimator.

The importance of clinical signs as well as radiological findings in the diagnosis of incomplete locked-in syndrome.

The importance of clinical signs as well as radiological findings in the diagnosis of incomplete locked-in syndrome.

Neural repair and rehabilitation: Implant helps patient with incomplete locked-in syndrome.

Neural repair and rehabilitation: Implant helps patient with incomplete locked-in syndrome.

Neural Point-and-Click Communication by a Person With Incomplete Locked-In Syndrome

A goal of brain–computer interface research is to develop fast and reliable means of communication for individuals with paralysis and anarthria. We evaluated the ability of an individual with incomplete locked-in syndrome enrolled in the BrainGate Neural Interface System pilot clinical trial to communicate using neural point-and-click control. A general-purpose interface was developed to provide control of a computer cursor in tandem with one of two on-screen virtual keyboards. The novel BrainGate Radial Keyboard was compared to a standard QWERTY keyboard in a balanced copy-spelling task. The Radial Keyboard yielded a significant improvement in typing accuracy and speed—enabling typing rates over 10 correct characters per minute. The participant used this interface to communicate face-to-face with research staff by using text-to-speech conversion, and remotely using an internet chat application. This study demonstrates the first use of an intracortical brain–computer interface for neural point-and-click communication by an individual with incomplete locked-in syndrome.

Locked in, but not out?

The most devastating aspect of amyotrophic lateral sclerosis (ALS) may not be the loss of mobility or spontaneous respiration but the inability to communicate. For people with ALS who elect mechanical ventilation, the inexorable disease progression can lead to an incomplete locked-in syndrome (LIS)1,2 and then to a total LIS where neither eye movements nor any other efferent capacity remains. The moment that occurs, consciousness undoubtedly persists, but for an unknown period of time. In some cases, years later, family members maintain that their loved one is communicating by changing pupil size or pulse rate, or just a look in the eye. The dispassionate physician remains uncertain, perhaps believing that consciousness requires not just an internal dialogue but also observing the results of thoughts or actions. Others may quietly hope that consciousness cannot survive extended periods of immobility, unannounced and unmitigated discomfort, and complete disconnection.

A rare sequela of acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis is a demyelinating disease, typically occurring in children following a febrile infection or a vaccination. Primary and secondary immune responses contribute to inflammation and subsequent demyelination, but the exact pathogenesis is still unknown. Diagnosis of acute disseminated encephalomyelitis is strongly suggested by temporal relationship between an infection or an immunization and the onset of neurological symptoms. Biopsy is definitive. In general, the disease is self-limiting and the prognostic outcome is favorable with anti-inflammatory and immunosuppressive agents. Locked-in syndrome describes patients who are awake and conscious but have no means of producing limb, speech, or facial movements. Locked-in syndrome is a rare complication of acute disseminated encephalomyelitis. We present a case of incomplete locked-in syndrome occurring in a 34-year-old male secondary to acute disseminated encephalomyelitis. Our case is unique, as acute disseminated encephalomyelitis occurred in a 34-year-old which was poorly responsive to immunosuppression resulting in severe disability.

Brain–Computer Interface With Language Model–Electroencephalography Fusion for Locked-In Syndrome

Background. Some noninvasive brain–computer interface (BCI) systems are currently available for locked-in syndrome (LIS) but none have incorporated a statistical language model during text generation. Objective. To begin to address the communication needs of individuals with LIS using a noninvasive BCI that involves rapid serial visual presentation (RSVP) of symbols and a unique classifier with electroencephalography (EEG) and language model fusion. Methods. The RSVP Keyboard was developed with several unique features. Individual letters are presented at 2.5 per second. Computer classification of letters as targets or nontargets based on EEG is performed using machine learning that incorporates a language model for letter prediction via Bayesian fusion enabling targets to be presented only 1 to 4 times. Nine participants with LIS and 9 healthy controls were enrolled. After screening, subjects first calibrated the system, and then completed a series of balanced word generation mastery tasks that were designed with 5 incremental levels of difficulty, which increased by selecting phrases for which the utility of the language model decreased naturally. Results. Six participants with LIS and 9 controls completed the experiment. All LIS participants successfully mastered spelling at level 1 and one subject achieved level 5. Six of 9 control participants achieved level 5. Conclusions. Individuals who have incomplete LIS may benefit from an EEG-based BCI system, which relies on EEG classification and a statistical language model. Steps to further improve the system are discussed.

Locked-in syndrome as a presentation of snakebite

Snake bite is a common condition in tropical countries. Neurotoxic features of snake bite vary from early morning neuroparalytic syndrome to various cranial nerve palsies. Locked in syndrome (LIS) is a rare presentation. We present four children that had LIS; three patients had total and one had incomplete LIS. All patients made successful recovery with polyvalent anti-snake venom and supportive management. This case series highlights the importance of early diagnosis of LIS in snake bite.

Head Pilot: A new webcam-based Head Tracking System tested in permanently disabled patients

Persons with cerebral palsy (CP) need to modify their lifestyle in order to carry out daily activities. Assistive technology facilitates communication and improves the domestic environment and mobility. The STARNAV Company has developed a Head Tracking System, Head Pilot, which uses a robust algorithm that measures, in real-time, head motion from a webcam. Head Pilot aims to control any informatic and domotic interface controlling the pointer of a PC. This work aims to create an assistive technology that is easy to use once it is set up and used. The system offers an interface control, which allows individual users to adjust the system for their comfort. The system displays a toolbar allowing the patient to choose the velocity of the pointer and to choose from several different ways to validate a task. The objective of this study was to evaluate the performance of Head Pilot by using five computerized tests of validation. Seven participants with disabilities were compared to seven participants with no relevant medical history (control group). Two versions of the software were developed and displayed on a computer screen. The time to complete the tests were measured and compared to a control group. Before testing, the disabled persons had received an orthoptic assessment, a cognitive evaluation, and a cervical motor check. Head Pilot was validated for use by the majority of users with CP who were able to control a computer except for the subject with incomplete locked-in syndrome, who required an Eye Tracker System.

Establishing capacity in a patient with incomplete locked‐in syndrome

AbstractPatients with locked‐in syndrome may have retained mental capacity to make decisions about their care and it is important that healthcare professionals prioritise communication rehabilitation. Here, Sarah Carrington and Jonathan Birns describe how they established capacity in a patient with incomplete locked‐in syndrome and helped him to communicate his current wishes regarding his treatment.

Incomplete Locked-in Syndrome

In this paper, we present a case of 62 year-old male with quadriplegia, dysarthria and preserved consciousness. Our case belongs to the incomplete variety of locked-in syndrome due to pontine infarction, because beside the vertical eye movements and eye lid movements, the patient had horizontal eye movements and finger movements on the right side. In general, the basilar artery occlusion is associated with poor outcome, however the urgent thrombolytic therapy may increase the chances to survive. The prognosis of our patient was disquieting and he died after 6 weeks from the onset.

Neuropsychologic Assessment and Cognitive Rehabilitation in a Patient With Locked-In Syndrome and Left Neglect

Trojano L, Moretta P, Estraneo A, Santoro L. Neuropsychologic assessment and cognitive rehabilitation in a patient with locked-in syndrome and left neglect. We describe a patient affected by severe incomplete locked-in syndrome (LIS) and left neglect caused by a combination of vascular lesions. Our patient's neglect prevented the use of augmentative communication devices based on a computerized eye-tracker system. For this reason, we adapted a visual scanning training for neglect rehabilitation. At the end of the rehabilitative training, the patient had regained full exploration of the monitor and could use the eye-tracker system for communicative purposes. This case report shows that specific rehabilitative approaches can be devised in severely disabled LIS patients with additional brain lesions and specific cognitive defects.

Rehabilitation including treadmill therapy for patients with incomplete locked-in syndrome after stroke; a case series study of motor recovery

Primary objective: The aim of this study was to explore changes in motor function in patients with incomplete LIS referred to rehabilitation.Research design: A prospective, explorative, multiple case study design was applied.Methods and procedures: A multidisciplinary intervention programme was conducted including treadmill therapy (TT) with body weight support. Patients being able to stand upright supported by a standing frame were consecutively recruited to TT from 2001–2005. Physical performance was recorded on video and treadmill data were registered. Performances of transfer and walking were selected as the focus of observation. Two external observers described the performances independently, using an observational form and validated the joint and condensed descriptions.Outcomes and results: A total of nine patients fulfilled the intervention programme and no adverse events were noted. Personal assistance and body weight support were reduced during the TT period and all patients demonstrated improved physical performance. While five patients were able to practice some kind of walking activity at the end of rehabilitation, four patients demonstrated improvement in body functions, showing better postural control.Conclusion: This study indicates that TT can be a safe and useful method to intensify the rehabilitation programme for patients with incomplete LIS.

Communicating using the eyes without remembering it: Cognitive rehabilitation in a severely brain-injured patient with amnesia, tetraplegia and anarthria

We describe here a case of cognitive rehabilitation in a young patient with closed head injury, who had dense anterograde amnesia and such disabling neurological defects (tetraplegia and anarthria) that the condition evoked some features of an incomplete locked-in syndrome. After a prolonged period of no communicative possibility, the patient underwent a specific training, based on principles of errorless learning, with the aim of using a computerized eye-tracker system. Although, due to memory disturbances, the patient always denied ever having used the eye-tracker system, learned to use the computerized device and improved interaction with the environment. This favourable outcome may serve as a stimulus for devising new training approaches in patients with complex patterns of cognitive impairments, even when associated with severe motor impairments.