RESUMO
Thermal imaging is used in medical diagnosis and preventive screening, e.g. breast cancer, cardiovascular disease, and orthopedics. Segmentation algorithms fail to recognize body parts of interest when the temperature difference between the body parts and the background is insufficient. We propose to perform segmentation in two stereoscopically acquired RGB images and to triangulate corresponding points extracted from those images into world coordinates. The thereby acquired world coordinates are projected into the thermal image plane for a more robust segmentation result. Our worked example is the segmentation of human hands. The extension of the thermal setup with two additional RGB cameras improves segmentation in our particular case, but could also make segmentation of other body parts in thermal images more robust. Comparing significant points like fingertips and the junctions between the fingers and the metacarpus, we come up with an average deviation of 1.03 pixel ± 0.82 pixel in x-axis direction and 1.04 pixel ± 0.62 pixel in y-axis direction, roughly corresponding to a mean Euclidean distance of 1.4 mm on the hands.
Assuntos
Algoritmos , Mãos/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Termografia , HumanosRESUMO
This paper presents a decentralized safety concept for networked intensive care setups, for which a decentralized network of sensors and actuators is realized by embedded microcontroller nodes. It is evaluated for up to eleven medical devices in a setup for automated acute respiratory distress syndrome (ARDS) therapy. In this contribution we highlight a blood pump supervision as exemplary safety measure, which allows a reliable bubble detection in an extracorporeal blood circulation. The approach is validated with data of animal experiments including 35 bubbles with a size between 0.05 and 0.3 ml. All 18 bubbles with a size down to 0.15 ml are successfully detected. By using hidden Markov models (HMMs) as statistical method the number of necessary sensors can be reduced by two pressure sensors.
Assuntos
Alarmes Clínicos , Cuidados Críticos/métodos , Circulação Extracorpórea/métodos , Monitorização Fisiológica/métodos , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/terapia , Terapia Assistida por Computador/métodos , Animais , Retroalimentação Fisiológica , Humanos , Monitorização Fisiológica/instrumentação , Segurança do Paciente , Reconhecimento Automatizado de Padrão/métodos , Resultado do TratamentoRESUMO
A new concept is presented for cooperative automation of mechanical ventilation and extracorporeal membrane oxygenation (ECMO) therapy for treatment of acute respiratory distress syndrome (ARDS). While mechanical ventilation is continuously optimized to promote lung protection, extracorporeal gas transfer rates are simultaneously adjusted to control oxygen supply and carbon dioxide removal using a robust patient-in-the-loop control system. In addition, the cooperative therapy management uses higher-level algorithms to adjust both therapeutic approaches. The controller synthesis is derived based on the introduced objectives, the experimental setup and the uncertain models. Finally, the autonomous ARDS therapy system capabilities are demonstrated and discussed based on in vivo data from animal experiments.
Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Pulmão/fisiopatologia , Modelos Biológicos , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Mecânica Respiratória , Animais , Terapia Combinada/instrumentação , Terapia Combinada/métodos , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Oxigenação por Membrana Extracorpórea/instrumentação , Retroalimentação Fisiológica , Humanos , Respiração Artificial/instrumentação , Síndrome do Desconforto Respiratório/diagnóstico , Integração de Sistemas , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos , Resultado do TratamentoRESUMO
In some cases of severe acute respiratory distress syndrome, hypoxemia occurs despite optimized conservative therapy; however, extracorporeal membrane oxygenation (ECMO) can assure sufficient gas exchange. To increase safety and reliability of devices, the oxygenator design was optimized integrating new plasma-resistant composite membranes and new blood pumps are used with longer durability and reduced blood cell damage. Another approach is the use of an arterio-venous pumpless extracorporeal lung assist (pECLA) using an oxygenator with reduced pressure drop to simplify management and to avoid pump-related complications. First attempts were made to integrate basic control and safety concepts in ECMO circuits, but this does not seem to be sufficient to overcome the specific problems of ECMO (long-term use and limited supervision of the intensive care unit). The integration of sophisticated automated control and safety concepts in combination with revised ECMO circuits could allow a more reliable application of ECMO of the intensive care unit without continuous observation by a perfusionist. Easier intra- and interhospital transfer of patients with running ECMO would be another advantage.