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Evaluation of development of cortical excitability in spinal cord injured patients using transcranial magnetic stimulation
Kříž, Jiří ; Kolář, Pavel (advisor) ; Jeřábek, Jaroslav (referee) ; Jech, Robert (referee)
In Ph.D. thesis we focused on monitoring and evaluation of changes in motor cortical excitability of patients after spinal cord injury. Explanation of motor cortex reaction on spinal function disorder could be useful in various therapeutic interventions. Seventeen spinal cord injured (SCI) patients (neurological level of injury from C3 to L3, AIS A-D) at the age from 18 to 63 (average 30.1) and 10 controls participated on the study. Neurological examination was performed according ASIA classification, evaluation of motor function of muscles was greatly important. Changes in primary motor cortical excitability were studied using paired-pulse transcranial magnetic stimulation (p-TMS). The paired pulses were applied at interstimulus intervals (ISI) of 2 ms and 15 ms while motor evoked potentials (MEP) were recorded in the biceps brachii (Bic), the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles. All patients underwent two examinations in first four months after SCI with month interval. Ten patients underwent third examination 2-3 years after injury. The study revealed a significant decrease in cortical excitability in the first weeks after SCI concerning the representation of both affected muscles and spared muscles rostral to the lesion. In motor-incompletely injured patients, but not in...
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Respiratory physiotherapy in neurology
Srp, Martin ; Jech, Robert (advisor) ; Baláž, Marek (referee) ; Konečný, Petr (referee)
Pneumonia is the leading cause of death in a large proportion of neurological diseases. Respiratory physiotherapy serves as a non-pharmacological option for supporting airway hygiene. However, current awareness of respiratory physiotherapy in neurological patients is not satisfactory. The aim of this thesis is to verify the effectiveness of expiratory muscle strength training (EMST) in three neurological diseases: multiple sclerosis (MS), Parkinson's disease (PD) and multiple system atrophy (MSA). The results of this thesis show: 1) EMST led to a significant increase in expiratory muscle strength and voluntary peak cough flow in patients with MS. Therefore, we have shown that EMST is an effective method of respiratory physiotherapy in promoting airway hygiene in patients with MS. 2) We found in a demographic study that the PD healthcare model in Czechia is suboptimal. The utilization of a respiratory physiotherapy is low, and therefore its reorganization is needed. 3) We developed and patented a mobile application SpiroGym which provides visual feedback during training and sends the training results via a secure server directly to the therapist for telemedicine needs. In a pilot study, we verified its feasibility in patients with PD. The study results indicate that EMST coupled with the SpiroGym...
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Somatomotor and somatosensory modulation of pain in the EEG and fMR image
Vrána, Jiří ; Stančák, Andrej (advisor) ; Vymazal, Josef (referee) ; Jech, Robert (referee) ; Hájek, Milan (referee)
Pain processing is modulated at different levels of the central nervous system by concurrent sensory and motor processes. From previous studies with innocuous somatosensory evoked potentials we know of the phenomenon of gating by movement. The classical explanation [Melzack R, Wall PD. Pain mechanisms: a new theory. Science 1965;150(699):971-979.] of the mechanism of gating in the posterior horn of spinal cord is complemented by other, lesser understood data, suggesting supraspinal mechanisms. A similar lack of understanding of the cortical mechanisms is seen in pain modulating methods using concurrent electrical nerve stimulation. This work is intended to further our understanding of the cortical mechanisms of pain modulation in the specific cases of (a) isometric muscle contraction of the right or left hand during painful electrical intraepidermal stimulation of the right index finger and (b) during observation of the acute effects of concurrent innocuous median nerve stimulation on painful tonic thermal stimulation of the thenar eminence.
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Neuromodulation in treatment of selected dystonic syndromes
Havránková, Petra ; Jech, Robert (advisor) ; Štětkářová, Ivana (referee) ; Rokyta, Richard (referee)
Dystonia is a neurological syndrome characterized by the involuntary contraction of opposing muscles, causing twisting movements or abnormal postures (modified by Fahn, 1987). Writer's cramp is the most common form of task-specific focal dystonia. In the first study, patients with writer's cramp were evaluated for differences in cortical activation during movements likely to induce cramps (complex movements) and movements which rarely lead to dystonia (simple movements). Although complex patient movements during fMRI were never associated with dystonic cramps, they exhibited abnormally decreased cortical activity. This was not observed in simple movements and was unrelated to the character of handwriting or the presence/absence of visual feedback. Our results support the theory of dualistic sensorimotor system behavior in writer's cramp. As the somatosensory system is believed to be affected in focal dystonia, we focused on modulation of the primary somatosensory cortex (SI) induced by repetitive transcranial magnetic stimulation (rTMS) in the second study, in order to improve writer's cramp. In conclusion, 1 Hz rTMS of the SI cortex can improve manifestations of writer's cramp while increasing cortical activity in both hemispheres. Handwriting as well as subjective assessment improved in most...
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Cortical and Subcortical Mechanisms of Time Perception
Dušek, Petr ; Jech, Robert (advisor) ; Mareš, Jaroslav (referee) ; Bareš, Martin (referee)
Deficits in interval timing have been described in focal brain lesions and in various neuropsychiatric disorders including Parkinson's disease (PD). The aim of this study was to explore brain areas responsible for human time perception and for the timing deficit in PD. We used a time reproduction task (TRT) which consisted of an encoding phase (during which visual stimuli of durations from 5 to 16.6 sec were presented) and a reproduction phase (during which interval durations were reproduced by a button pressing). In our first fMRI study, we used a parametric modulated analysis searching for brain areas with activity, expressed as Blood Oxygenation Level Dependent (BOLD) signal, correlated with the duration of time interval. During the encoding phase, there was a gradual deactivation of the left prefrontal cortex (PFC) and cingulate gyrus. During the reproduction phase, there was a gradual deactivation in precuneus and an accumulation of activity in the left PFC, primary motor area, right caudate and supplementary motor area (SMA). The second study aimed at supporting the role of two of these areas, SMA and precuneus in interval timing by repetitive transcranial magnetic stimulation (rTMS). Accuracy and variability of time estimates were compared before and after rTMS. Accuracy of estimates was not...
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Pathophysiological mechanisms of the pallidal deep brain stimulation in dystonic syndromes
Fečíková, Anna ; Jech, Robert (advisor) ; Nevrlý, Martin (referee) ; Škorvánek, Matej (referee)
Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective symptomatic treatment for pharmacoresistant dystonic syndromes. The relationship between grey matter volume and intracortical inhibition of the primary motor cortex (MI) in regard to the effectiveness and the state (ON/OFF) of GPi DBS was analysed in the first study. The grey matter of chronically treated patients showed hypertrophy of the supplementary motor area and cerebellar vermis whereas this difference was more significant in patients with a better clinical outcome. The grey matter of the cerebellar hemispheres of the patients showed positive correlation with the improvement of an intracortical inhibition which was generally less effective in patients regardless of the GPi DBS state. Moreover, we showed the same level of SICI in the good responders as in the healthy controls, while in non-responders was the SICI decreased. In the second study, by using paired associative stimulation (PAS) we studied the influence of primary somatosensory cortex (SI) on the MI excitability in dystonia in regards to the effectiveness of GPi DBS. SI PAS decreased the MI excitability in the GPi DBS ON state while switching the stimulation off decreased an inhibitory effect of SI on MI excitability. Non-responders showed a...
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Kinematic analysis of rhythmic motion: the cases of human hand tremor and fly wingbeat.
Chakraborty, Soma ; Zápotocký, Martin (advisor) ; Maršálek, Petr (referee) ; Jech, Robert (referee)
Rhythmic motions, regular or irregular, are an integral part of motor behavior both in health and in disease. Better understanding of its neural control mechanisms helps in developing methods for controlling the progression of diseases manifesting as rhythmic motions. I studied two specific aspects of rhythmic motions: bilateral coordination of hand tremors in human subjects and modular control of locomotion in invertebrates. Many types of tremors, including the physiological tremor (PT) and the essential tremor (ET) occur in limbs on both the sides of the body, with similar fundamental frequency of the oscillation. This raises the possibility that the contralateral tremors may have a common source or are otherwise coupled. However, while significant contralateral interaction is seen in these two types of tremors, only limited evidence of bilateral coherence has been shown in the previous literature. Therefore, in my study I explored the existence of a weak coupling between the left and right oscillators the may lead to intermittent bilateral coherence. I measured triaxial acceleration of the two hands and systematically assessed their bilateral coherence, using both stationary and non-stationary (wavelet-based) analyses methods. Measuring all three axes allowed examination of a more complete set...
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The effect of hypothermia on outcome and neurologic injury after prolonged cardiac arrest treated by emergency preservation and delayed resuscitation
Drábek, Tomáš ; Jech, Robert (advisor) ; Hess, Ladislav (referee) ; Mareš, Jan (referee)
5 Summary: Currently, the outcomes from traumatic exsanguination cardiac arrest (CA) show that over 50% of deaths due to trauma occur at the scene, where medical care is limited. Less than 10% of patients who become pulseless from trauma survive. However, in an appropriate setting, some of those traumatic injuries could be surgically repairable. Emergency preservation and resuscitation (EPR) is a novel approach for resuscitation of exsanguination CA victims. EPR uses deep hypothermic preservation for prolonged CA to buy time for transport, damage control surgery, and delayed resuscitation with cardiopulmonary bypass (CPB). Initially, we used a dog model to maximize clinical relevance. We showed that the efficacy of EPR is related to the depth of hypothermia and duration of CA. Pharmacologic adjuncts tested to augment hypothermia generally failed. Extended hemorrhagic shock did not prevent the success of EPR vs. conventional resuscitation if extended post-resuscitative hypothermia was provided. Oxygenation of the flush allowed extending of survivable duration of deep hypothermic CA. Because of the lack of molecular tools available for use in dogs, we developed a rat EPR model to study the cellular and molecular mechanisms underlying deep hypothermic neuroprotection to allow us to define specific targets for...
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Evaluation of development of cortical excitability in spinal cord injured patients using transcranial magnetic stimulation
Kříž, Jiří ; Kolář, Pavel (advisor) ; Jeřábek, Jaroslav (referee) ; Jech, Robert (referee)
In Ph.D. thesis we focused on monitoring and evaluation of changes in motor cortical excitability of patients after spinal cord injury. Explanation of motor cortex reaction on spinal function disorder could be useful in various therapeutic interventions. Seventeen spinal cord injured (SCI) patients (neurological level of injury from C3 to L3, AIS A-D) at the age from 18 to 63 (average 30.1) and 10 controls participated on the study. Neurological examination was performed according ASIA classification, evaluation of motor function of muscles was greatly important. Changes in primary motor cortical excitability were studied using paired-pulse transcranial magnetic stimulation (p-TMS). The paired pulses were applied at interstimulus intervals (ISI) of 2 ms and 15 ms while motor evoked potentials (MEP) were recorded in the biceps brachii (Bic), the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles. All patients underwent two examinations in first four months after SCI with month interval. Ten patients underwent third examination 2-3 years after injury. The study revealed a significant decrease in cortical excitability in the first weeks after SCI concerning the representation of both affected muscles and spared muscles rostral to the lesion. In motor-incompletely injured patients, but not in...
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