Functional magnetic resonance imaging under anaesthesia of a patient with severe chronic disorders of consciousness.

CLINICAL CASE: We report on a 19-year old male patient who is recovering from near-drowning. The patient was admitted for re-evaluation in a Minimally Conscious State. METHOD: A regular functional Magnetic Resonance Imaging was not possible due to complex motor tics of the patient with sudden flexion and extension movements of arms and legs as well as opisthotonic retroflexion of the head and trunk. Thus, the patient was anaesthetised and functional Magnetic Resonance Imaging was performed under general anaesthesia which was introduced and maintained with Sevoflorane and Fentanyl provided analgesia. Four functional runs were performed and the patient's responses were recorded. During each one of these runs one extremity (dorsum manus or pedis) was stimulated with a brush with an operator-paced frequency of about 2 Hz. RESULTS AND CONCLUSION: Clear responses were found in the somatosensory cortex contra lateral within the post central gyrus during stimulation of the left hand. Considering the other three extremities no significant responses were found. Nevertheless, we conclude that a functional Magnetic Resonance Imaging under anaesthesia is possible for patients with severe chronic disorders of consciousness and brain areas responding to stimuli can be detected.

Cortical excitability changes in patients with sleep-wake disturbances after traumatic brain injury.

Although chronic sleepiness is common after head trauma, the cause remains unclear. Transcranial magnetic stimulation (TMS) represents a useful complementary approach in the study of sleep pathophysiology. We aimed to determine in this study whether post-traumatic sleep-wake disturbances (SWD) are associated with changes in excitability of the cerebral cortex. TMS was performed 3 months after mild to moderate traumatic brain injury (TBI) in 11 patients with subjective excessive daytime sleepiness (EDS; defined by the Epworth Sleepiness Scale ≥10), 12 patients with objective EDS (as defined by mean sleep latency <5 on multiple sleep latency tests), 11 patients with fatigue (defined by daytime tiredness without signs of subjective or objective EDS), 10 patients with post-traumatic hypersomnia "sensu strictu," and 14 control subjects. Measures of cortical excitability included central motor conduction time, resting motor threshold (RMT), short-latency intracortical inhibition (SICI), and intracortical facilitation to paired-TMS. RMT was higher and SICI was more pronounced in the patients with objective EDS than in the control subjects. In the other patients all TMS parameters did not differ significantly from the controls. Similarly to that reported in patients with narcolepsy, the cortical hypoexcitability may reflect the deficiency of the excitatory hypocretin/orexin-neurotransmitter system. These observations may provide new insights into the causes of chronic sleepiness in patients with TBI. A better understanding of the pathophysiology of post-traumatic SWD may also lead to better therapeutic strategies in these patients.

[Scuba diving -- a therapeutic option for patients with paraplegia]. / Tauchen als therapeutische Option bei Patienten mit Querschnittsyndrom.

OBJECTIVE: Spasticity is often a handicap in paraplegics and interferes with quality of life. Medical therapeutic options (e.g. baclofen, tizanidin) lead to drowsiness, fatigue and loss in activity. On the other hand paraplegics are increasingly active in daily life and leisure (paralympics). Neurorehabilitation is effective in reduction of spasticity, gaining motor function and enhancing quality of life. Hippotherapy (Lechner et al 2003) and aquatic rehabilitation are additive methods. Already 15 years ago Madorsky et al pointed out SCUBA diving as a positive neurorehabilitation procedure. The study group around Stanghelle reported also beneficial aspects on spasticity of patients with spinal cord injuries. These references inspired to introduce a prospective study. METHODS: After obtaining an ethic votum and evaluation assessment for diving permission 6 volunteers with paraplegia entered the pilot study. Medication was kept stable throughout the study time. Supervised by diving instructors and a diving trained doctor the volunteers dived to a platform in the depth of 7.2 meters. The daily diving time was exactly 30 minutes. Stabilized on the platform physiotherapeutic assessment took place in different positions to reduce spasticity. Ashworth Scale and spasm frequency scale were noted daily and at beginning and end of the study the WHO Quality of life Test had to be completed. For objective reasons a locomat training happened before, within a week after and 4 weeks after the study week. RESULTS: All patients did the daily dives without any difficulties. The statistics included the assessment of day 1 versus day 7 of 5 patients and showed a significant reduction of Modified Ashwoth Scale (p=0.04). Quality of life showed an improvement. CONCLUSION: The improvement rationale can only be supposed. A correlation to the ambient pressure suggests itself. Therefore deeper depths should increase the good spasticity results or manage to achieve those faster. Many questions remain, so further studies are necessary to ascertain the ideal standard options.

Guidelines for Quality Management of Apallic Syndrome / Vegetative State.

INTRODUCTION: Epidemiology in Europe shows constantly increasing figures for the apallic syndrome (AS)/vegetative state (VS) as a consequence of advanced rescue, emergency services, intensive care treatment after acute brain damage and high-standard activating home nursing for completely dependent end-stage cases secondary to progressive neurological disease. Management of patients in irreversible permanent AS/VS has been the subject of sustained scientific and moral-legal debate over the past decade. METHODS: A task force on guidelines for quality management of AS/VS was set up under the auspices of the Scientific Panel Neurotraumatology of the European Federation of Neurological Societies to address key issues relating to AS/VS prevalence and quality management. Collection and analysis of scientific data on class II (III) evidence from the literature and recommendations based on the best practice as resulting from the task force members' expertise are in accordance with EFNS Guidance regulations. FINDINGS: The overall incidence of new AS/VS full stage cases all etiology is 0.5-2/100.000 population per year. About one third are traumatic and two thirds non traumatic cases. Increasing figures for hypoxic brain damage and progressive neurological disease have been noticed. The main conceptual criticism is based on the assessment and diagnosis of all different AS/VS stages based solely on behavioural findings without knowing the exact or uniform pathogenesis or neuropathological findings and the uncertainty of clinical assessment due to varying inclusion criteria. No special diagnostics, no specific medical management can be recommended for class II or III AS treatment and rehabilitation. This is why sine qua non diagnostics of the clinical features and appropriate treatment of AS/VS patients of "AS full, remission, defect and end stages" require further professional training and expertise for doctors and rehabilitation personnel. INTERPRETATION: Management of AS aims at the social reintegration of patients or has to guarantee humanistic active nursing if treatment fails. Outcome depends on the cause and duration of AS/VS as well as patient's age. There is no single AS/VS specific laboratory investigation, no specific regimen or stimulating intervention to be recommended for improving higher cerebral functioning. Quality management requires at least 3 years of advanced training and permanent education to gain approval of qualification for AS/VS treatment and expertise. Sine qua non areas covering AS/VS institutions for early and long-term rehabilitation are required on a population base (prevalence of 2/100.000/year) to quicken functional restoration and to prevent or treat complications. Caring homes are needed for respectful humane nursing including basal sensor-motor stimulating techniques. Passive euthanasia is considered an act of mercy by physicians in terms of withholding treatment; however, ethical and legal issues with regard to withdrawal of nutrition and hydration and end of life discussions raise deep concerns. The aim of the guideline is to provide management guidance (on the best medical evidence class II and III or task force expertise) for neurologists, neurosurgeons, other physicians working with AS/VS patients, neurorehabilitation personnel, patients, next-of-kin, and health authorities.

Contact force- and amplitude-controllable vibrating probe for somatosensory mapping of plantar afferences with fMRI.

PURPOSE: To study cerebral responses evoked from mechanoreceptors in the human foot sole using a computer-controlled vibrotactile stimulation system. MATERIALS AND METHODS: The stimulation system consisted of two stationary moving magnet actuators with indentors to gently contact and vibrate the foot sole during functional MRI (fMRI) experiments. To allow independent settings of contact force (0-20 N) and intensity of vibration (frequency range=20-100 Hz) the actuators were controlled by a digital servo loop. For fMRI experiments with complex stimulus protocols, both vibrating probes were further operated under supervisory control. RESULTS: The MR compatibility of this electromagnetic system was tested in a 1.5T scanner with an actively shielded magnet (Siemens Magnetom Sonata). Blood oxygenation level-dependent (BOLD) responses were detected in the contralateral left pre- and postcentral gyrus, bilaterally within the secondary somatosensory cortex, bilaterally within the supplementary motor cortex, and bilaterally within the anterior cingular gyrus. CONCLUSION: This stimulation device provides a new tool for identifying cerebral structures that convey sensory information from the foot region, which is of promising diagnostic value, particularly for assessing sensorimotor deficits resulting from brain lesions.

Human brain structures related to plantar vibrotactile stimulation: a functional magnetic resonance imaging study.

The purpose of this study was to investigate the sensorimotor cortex response to plantar vibrotactile stimulation using a newly developed MRI compatible vibration device. Ten healthy subjects (20-45 years) were investigated. Vibrotactile stimulation of the sole of the foot with a frequency of 50 Hz and a displacement of 1 mm was performed during fMRI (echo-planar imaging sequence at 1.5 T) using an MRI compatible moving magnet actuator that is able to produce vibration frequencies between 0 and 100 Hz and displacement amplitudes between 0 and 4 mm. The fMRI measurement during vibrotactile stimulation of the right foot revealed brain activation contralaterally within the primary sensorimotor cortex, bilaterally within the secondary somatosensory cortex, bilaterally within the superior temporal, inferior parietal, and posterior insular region, bilaterally within the anterior and posterior cingular gyrus, bilaterally within the thalamus and caudate nucleus, contralaterally within the lentiform nucleus, and bilaterally within the anterior and posterior cerebellar lobe. The advantages of the new MRI compatible vibration device include effective transmission of the stimulus and controlled vibration amplitudes, frequencies, and intensities. The results indicate that plantar vibration can be a suitable paradigm to observe activation within the sensorimotor network in fMRI. Furthermore, the method may be used to determine the optimal responsiveness of the individual sensorimotor network.