Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference
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Conf Proc IEEE Eng Med Biol Soc · Jan 2006
Coma duration prediction in diffuse axonal injury: analyses of apparent diffusion coefficient and clinical prognostic factors.
The purpose of this paper is to evaluate the hypothesis that the Apparent Diffusion Coefficient (ADC) values combined with initial clinical factors indicates the depth of shearing lesions in the brain structure and therefore relates to coma duration of diffuse axonal injury (DAI). Seventy-four adult patients (48 male and 26 female patients) with diffuse axonal injury were examined with convention MR imaging and diffusion weighted MR imaging between 2 hours and 20 days after injury. Apparent diffusion coefficient (ADC) maps were obtained and the mean ADC values of each Region of Interest (ROI) were measured using MRI console software. ⋯ Post-traumatic coma duration of DAI could be predicted by cerebral MRI findings in the acute to subacute stage after head injury combined with clinical prognostic factors. Age, ADC scores, GCS, number of lesions are highly significant in predicting coma duration. The technique presented herein might provide a tool for in vivo detection of DAI for the coma duration at the early stages in patients with traumatic brain injury.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2006
Implementation of a burn scar assessment system by ultrasound techniques.
Tissue injury and its ensuing healing process cause scar formation. In addition to physical disability, the subsequent disfigurements from burns often bring negative psychological impacts on the survivors. Scar hypertrophy and contracture limit the joint motion and body function of the patient. ⋯ In this report, the quantitative assessment system was used to evaluate the scar of a seriously burned patient. In order to verify the reliability of systematic reconstruction method, we constructed a phantom to imitate the scar tissue. The results show that it can achieve more than 90% in accuracy.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2006
Continuous cardiac output and left atrial pressure monitoring by pulmonary artery pressure waveform analysis.
We introduce a novel technique for continuous (i.e., automatic) monitoring of cardiac output (CO) and left atrial pressure (LAP) by mathematical analysis of a pulmonary artery pressure (PAP) waveform. To obtain an initial evaluation of the technique, we applied it to PAP waveforms obtained from nine critically ill patients and compared the resulting CO and LAP estimates with standard operator-dependent thermodilution and pulmonary capillary wedge pressure measurements, respectively. We report that the technique achieved an overall CO error of 17.2% and an overall LAP error of 15.8%. With further testing, the technique may ultimately be employed so as to permit, for the first time, continuous CO and LAP monitoring in critically ill patients.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2006
Transpulmonary dilution system identification for pulmonary blood volume measurements by contrast echocardiography.
Pulmonary blood volume (PBV) is an important parameter to assess the condition of the lungs and the transpulmonary circulation. Unfortunately, its measurement is limited by the need for central catheterization. Contrast ultrasonography allows overcoming this problem. ⋯ Volume measurements show accurate in-vitro results with a correlation coefficient higher than 0.99. The clinical feasibility is confirmed by 70 measurements in patients. Beyond an accurate quantification of pulmonary blood volume, the proposed method also permits the characterization of the transpulmonary hemodynamics, possibly adding novel diagnostic value to the measurement.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2006
Observer design in switching control of neuromuscular blockade: clinical cases.
This paper concerns the application of multiple model switched methods to the control of neuromuscular blockade of patients undergoing anaesthesia. Since the model representing the neuromuscular blockade process is subject to a high level of uncertainty due both to inter-patient variability and time variations, switched methods provide the adaptation capability needed to achieve the desired performance. ⋯ Guidelines are provided for adequate selection of the characteristic polynomial defining the observer error dynamics. Second, clinical results using atracurium as blocking agent are reported in order to illustrate the use of the proposed control structure in actual clinical practice.