Effect of repetitive transcranial magnetic stimulation combined with median nerve electrical stimulation on patients with prolonged disorders of consciousness in different age / 中国康复理论与实践

ObjectiveTo investigate the effect of combination with repetitive transcranial magnetic stimulation (rTMS) and median nerve electrical stimulation (MNS) on patients with prolonged disorders of consciousness (pDOC) in different age. MethodsFrom January, 2021 to May, 2023, 93 patients with pDOC in the First Affiliated Hospital of Nanchang University were divided into young group (≤ 45 years old), middle-aged group (46 to 60 years old) and elderly group (> 60 years old). All the groups were treated with rTMS and MNS for four weeks. The Coma Recovery Scale-Revised (CRS-R), Glasgow Coma Scale (GCS), and Full Outline of Unresponsiveness Scale (FOUR) were used to evaluate the efficiency of awakening after treatment and the awakening ratios were compared among three groups weekly. Four weeks after treatment, regional cerebral blood flow (rCBF) was measured with CT perfusion imaging. The score of Glasgow Outcome Scale Extended (GOS-E) was compared six months after treatment. ResultsFrom three weeks after treatment, the scores of CRS-R, GCS and FOUR increased in all groups (P < 0.05). After weekly treatment, there was no significant difference in the composition ratio of consciousness level and the awakening ratio among three groups (χ2 < 11.057, P > 0.05). After four weeks of treatment, rCBF improved in three groups (|t| > 2.495, P < 0.05), however, there was no difference among three groups (F < 1.887, P > 0.05). There was no difference in the score of GOS-E at six months after treatment (F = 3.083, P = 0.055). ConclusionrTMS combined with MNS is effective on pDOC patients in different ages, and elderly patients could also benefit from it.

Treatments for prolonged disorder of consciousness in recent five years: a visualized analysis / 中国康复理论与实践

ObjectiveTo investigate the current landscape and hotspots on researches about treatment of prolonged disorder of consciousness (pDOC) in the recent five years, and forecast the trends. MethodsLiterature about treatment of pDOC was retrieved from the Web of Science Core Collection database, from January 1st, 2019, to June 7th, 2023. The data were analyzed with CiteSpace 5.8.R3 to create knowledge maps for authors, countries, institutions, keywords, references, co-cited authors and co-cited literature. ResultsA total of 411 articles were included. Aurore Thibaut was the most influential author, Belgium was the most influential country, and Harvard Medical School was the institution with the most publications. The researches focused on neuromodulation, prognostic assessment and care, and management of swallowing function. The neuromodulation techniques mainly included transcranial direct current stimulation, repetitive transcranial magnetic stimulation, deep brain stimulation and transcutaneous auricular vague nerve stimulation. In the coming years, the researches trended to explore neuromodulation and mechanisms of consciousness recovery, and the main neuromodulation techniques might be deep brain stimulation and transcutaneous auricular vague nerve stimulation. ConclusionThe researches about treatment of pDOC are increasing, mainly focusing on neuromodulation, prognostic evaluation, nursing care, and training for swallowing function. More researches would focus on neuromodulation and mechanisms for restoring consciousness.

Neuroimage-Based Consciousness Evaluation of Patients with Secondary Doubtful Hydrocephalus Before and After Lumbar Drainage / 神经科学通报·英文版

Hydrocephalus is often treated with a cerebrospinal fluid shunt (CFS) for excessive amounts of cerebrospinal fluid in the brain. However, it is very difficult to distinguish whether the ventricular enlargement is due to hydrocephalus or other causes, such as brain atrophy after brain damage and surgery. The non-trivial evaluation of the consciousness level, along with a continuous drainage test of the lumbar cistern is thus clinically important before the decision for CFS is made. We studied 32 secondary mild hydrocephalus patients with different consciousness levels, who received T1 and diffusion tensor imaging magnetic resonance scans before and after lumbar cerebrospinal fluid drainage. We applied a novel machine-learning method to find the most discriminative features from the multi-modal neuroimages. Then, we built a regression model to regress the JFK Coma Recovery Scale-Revised (CRS-R) scores to quantify the level of consciousness. The experimental results showed that our method not only approximated the CRS-R scores but also tracked the temporal changes in individual patients. The regression model has high potential for the evaluation of consciousness in clinical practice.

Neuroimage-Based Consciousness Evaluation of Patients with Secondary Doubtful Hydrocephalus Before and After Lumbar Drainage / 神经科学通报·英文版

Hydrocephalus is often treated with a cerebrospinal fluid shunt (CFS) for excessive amounts of cerebrospinal fluid in the brain. However, it is very difficult to distinguish whether the ventricular enlargement is due to hydrocephalus or other causes, such as brain atrophy after brain damage and surgery. The non-trivial evaluation of the consciousness level, along with a continuous drainage test of the lumbar cistern is thus clinically important before the decision for CFS is made. We studied 32 secondary mild hydrocephalus patients with different consciousness levels, who received T1 and diffusion tensor imaging magnetic resonance scans before and after lumbar cerebrospinal fluid drainage. We applied a novel machine-learning method to find the most discriminative features from the multi-modal neuroimages. Then, we built a regression model to regress the JFK Coma Recovery Scale-Revised (CRS-R) scores to quantify the level of consciousness. The experimental results showed that our method not only approximated the CRS-R scores but also tracked the temporal changes in individual patients. The regression model has high potential for the evaluation of consciousness in clinical practice.

White Matter Deficits Underlying the Impaired Consciousness Level in Patients with Disorders of Consciousness / 神经科学通报·英文版

In this study, we aimed to (1) identify white matter (WM) deficits underlying the consciousness level in patients with disorders of consciousness (DOCs) using diffusion tensor imaging (DTI), and (2) evaluate the relationship between DTI metrics and clinical measures of the consciousness level in DOC patients. With a cohort of 8 comatose, 8 unresponsive wakefulness syndrome/vegetative state, and 14 minimally conscious state patients and 25 patient controls, we performed group comparisons of the DTI metrics in 48 core WM regions of interest (ROIs), and examined the clinical relevance using correlation analysis. We identified multiple abnormal WM ROIs in DOC patients compared with normal controls, and the DTI metrics in these ROIs were significantly correlated with clinical measures of the consciousness level. Therefore, our findings suggested that multiple WM tracts are involved in the impaired consciousness levels in DOC patients and demonstrated the clinical relevance of DTI for DOC patients.

Spinal Cord Stimulation Frequency Influences the Hemodynamic Response in Patients with Disorders of Consciousness / 神经科学通报·英文版

Spinal cord stimulation (SCS) is a promising technique for treating disorders of consciousness (DOCs). However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unclear. In this pilot study, functional near-infrared spectroscopy was used to measure the hemodynamic responses of 10 DOC patients to different SCS frequencies (5 Hz, 10 Hz, 50 Hz, 70 Hz, and 100 Hz). In the prefrontal cortex, a key area in consciousness circuits, we found significantly increased hemodynamic responses at 70 Hz and 100 Hz, and significantly different hemodynamic responses between 50 Hz and 70 Hz/100 Hz. In addition, the functional connectivity between prefrontal and occipital areas was significantly improved with SCS at 70 Hz. These results demonstrated that SCS modulates the hemodynamic responses and long-range connectivity in a frequency-specific manner (with 70 Hz apparently better), perhaps by improving the cerebral blood volume and information transmission through the reticular formation-thalamus-cortex pathway.

Visual Fixation Assessment in Patients with Disorders of Consciousness Based on Brain-Computer Interface / 神经科学通报·英文版

Visual fixation is an item in the visual function subscale of the Coma Recovery Scale-Revised (CRS-R). Sometimes clinicians using the behavioral scales find it difficult to detect because of the motor impairment in patients with disorders of consciousness (DOCs). Brain-computer interface (BCI) can be used to improve clinical assessment because it directly detects the brain response to an external stimulus in the absence of behavioral expression. In this study, we designed a BCI system to assist the visual fixation assessment of DOC patients. The results from 15 patients indicated that three showed visual fixation in both CRS-R and BCI assessments and one did not show such behavior in the CRS-R assessment but achieved significant online accuracy in the BCI assessment. The results revealed that electroencephalography-based BCI can detect the brain response for visual fixation. Therefore, the proposed BCI may provide a promising method for assisting behavioral assessment using the CRS-R.

Responses of Patients with Disorders of Consciousness to Habit Stimulation: A Quantitative EEG Study / 神经科学通报·英文版

Whether habit stimulation is effective in DOC patient arousal has not been reported. In this paper, we analyzed the responses of DOC patients to habit stimulation. Nineteen DOC patients with alcohol consumption or smoking habits were recruited and 64-channel EEG signals were acquired both at the resting state and at three stimulation states. Wavelet transformation and nonlinear dynamics were used to extract the features of EEG signals and four brain lobes were selected to investigate the degree of EEG response to habit stimulation. Results showed that the highest degree of EEG response was from the call-name stimulation, followed by habit and music stimulations. Significant differences in EEG wavelet energy and response coefficient were found both between habit and music stimulation, and between habit and call-name stimulation. These findings prove that habit stimulation induces relatively more intense EEG responses in DOC patients than music stimulation, suggesting that it may be a relevant additional method for eliciting patient arousal.

Spatial Properties of Mismatch Negativity in Patients with Disorders of Consciousness / 神经科学通报·英文版

In recent decades, event-related potentials have been used for the clinical electrophysiological assessment of patients with disorders of consciousness (DOCs). In this paper, an oddball paradigm with two types of frequency-deviant stimulus (standard stimuli were pure tones of 1000 Hz; small deviant stimuli were pure tones of 1050 Hz; large deviant stimuli were pure tones of 1200 Hz) was applied to elicit mismatch negativity (MMN) in 30 patients with DOCs diagnosed using the JFK Coma Recovery Scale-Revised (CRS-R). The results showed that the peak amplitudes of MMN elicited by both large and small deviant stimuli were significantly different from baseline. In terms of the spatial properties of MMN, a significant interaction effect between conditions (small and large deviant stimuli) and electrode nodes was centered at the frontocentral area. Furthermore, correlation coefficients were calculated between MMN amplitudes and CRS-R scores for each electrode among all participants to generate topographic maps. Meanwhile, a significant negative correlation between the MMN amplitudes elicited by large deviant stimuli and the CRS-R scores was also found at the frontocentral area. In consequence, our results combine the above spatial properties of MMN in patients with DOCs, and provide a more precise location (frontocentral area) at which to evaluate the correlation between clinical electrophysiological assessment and the level of consciousness.

Current Status of Neuromodulatory Therapies for Disorders of Consciousness / 神经科学通报·英文版

Treatment for disorders of consciousness (DOCs) is still a Gordian knot. Evidence-based guidelines on the treatment of DOC patients are not currently available, while neuromodulation techniques are seen as a potential treatment. Multiple neuromodulation therapies have been applied. This article reviews the most relevant studies in the literature in order to describe a clear picture of the current state of neuromodulation therapies that could be used to treat DOC patients. Both invasive and non-invasive brain stimulation is discussed. Significant behavioral improvements in prolonged DOCs under neuromodulation therapies are rare. The efficacy of various such therapies remains a matter of debate. Further clinical investigations of existing techniques in larger samples properly controlling for spontaneous recovery are needed, and new approaches are awaited.