Chronic disorders of consciousness

Abstract

Abstract. Over the last 20 years, studies have provided greater insight into disorders of consciousness (DOC), also known as altered state of consciousness. Increased brain residual functions have been identified in patients with DOC due to the successful application of novel next-generation imaging technologies. Many unconscious patients have now been confirmed to retain considerable cognitive functions. It is hoped that greater insight regarding the psychological state of patients may be achieved through the use of functional magnetic resonance imaging and brain-computer interfaces. However, issues surrounding the research and treatment of DOC remain problematic. These include differing opinions on the definition of consciousness, difficulties in diagnosis, assessment, prognosis and/or treatment, and newly emerging ethical, legal and social issues. To overcome these, appropriate care must be offered to patients with DOC by clinicians and families, as DOC patients may now be considered to live in more than just a vegetative state. The present article reviews the controversy surrounding the definition of consciousness and the reliability of novel technologies, prognostic prediction, communication with DOC patients and treatment methods. The ethical and social issues surrounding the treatment of DOC and future perspectives are also considered.

Effects of Long-Lasting High-Definition Transcranial Direct Current Stimulation in Chronic Disorders of Consciousness: A Pilot Study

“…The CRS-R is a standardized behavioral assessment measure that has been widely used for diagnostic assessment and outcome measurement in patients with DOC (Gerrard et al, 2014). However, the rate of clinical misdiagnosis based on the CRS-R remains high (Xie et al, 2017). Previous results have demonstrated EEG can detect and analyze brain activity in clinical practice (Lehembre et al, 2012; Bai et al, 2017a,b).…”

Brain Oscillatory Activity during Tactile Stimulation Correlates with Cortical Thickness of Intact Areas and Predicts Outcome in Post-Traumatic Comatose Patients

“…A correlation analysis between tactile EEG response and patient outcome showed that patients with better outcomes, such as recovery, had a more pronounced decrease in theta rhythm PSD during tactile stimulation (trend significance: r = −0.55, p = 0.01). The increase of beta rhythm (17)(18)(19)(20) Hz) power in central areas was correlated with the thickness of paracentral (r = 0.82, p = 0.0005) and precentral (r = 0.80, p = 0.0007) areas bilaterally (Figure 6). A correlation analysis between tactile EEG response and patient outcome showed that patients with better outcomes, such as recovery, had a more pronounced decrease in theta rhythm PSD during tactile stimulation (trend significance: r = −0.55, p = 0.01).…”

“…Electroencephalography (EEG) has shown variable abnormal activity in comatose patients after TBI. Mecarelli et al showed that background activity progressively decreased in amplitude until the eventual attenuation or suppression of cortical bioelectrical activity [ 18 ]. Spindle comas accompanied pontomesencephalic junction lesions when epileptiform activity and sleep spindles appeared along with the functional preservation of the remaining EEG patterns [ 19 ].…”

“…However, individual EEG indices may aid the evaluation of outcome prognosis. For example, an alpha coma pattern and low voltage, slow, nonreactive patterns were generally considered biomarkers for poor outcomes [ 18 , 22 ], and spindle comas were associated with good outcomes [ 19 ]. Patients with bilateral independent periodic lateralized epileptiform discharges had a higher mortality rate than patients with the unilateral form [ 21 ].…”

Addressing Pain for a Proper Rehabilitation Process in Patients With Severe Disorders of Consciousness

“…A requisite for conscious behaviors is the presence of adequate arousal (i.e., wakefulness) and awareness of content (i.e., sensory, cognitive, and affective experience) ( Giacino et al, 2018 ). The first is referred to the level of consciousness and the second to the content of consciousness ( Xie et al, 2017 ; Giacino et al, 2018 ).…”