Marcelli E, Scalambra F, Cercenelli L, Plicchi G
Università di Bologna, Dipartimento di Discipline Chirurgiche, Rianimatorie e dei Trapianti, Italy.
Med Eng Phys. 2007 Jan;29(1):140-7. doi: 10.1016/j.medengphy.2005.12.003. Epub 2006 Feb 28.
In implantable medical devices (IMDs), the need of telemetry systems able to provide wireless bidirectional communication to interrogate and remotely program the device, as well as to monitor the physiological status of the patient, is growing. The object of the present study was to evaluate a new hermetic antenna for wireless short-range transmission system for IMDs which would assure reliable long-term functioning due to the high level of hermeticity of antenna's housing that limits the influence of body tissue environment on transmitted signals. Experimental tests were conducted on three different prototypes to evaluate the most efficient antenna configuration for transmission both in the air and through a mixture simulating the human thorax. Further tests were performed to assess the influence of electro-catheters connected to IMDs on transmitted signals. Results showed that the hermetic antenna guarantees a good wireless transmission both in the air and through the human thorax simulator. The results also show that the presence of an electro-catheter can influence the effective radiated power (ERP) transmitted depending on its position in relation to the telemetric circuitry. Both a controlled increase of the ERP without exceeding the limits imposed by rules and the optimization of the tuning between the antenna and the transmitter can assure a reliable short-range transmission (several meters) using the new hermetic antenna proposed.
在植入式医疗设备（IMD）中，能够提供无线双向通信以询问和远程编程设备以及监测患者生理状态的遥测系统的需求日益增长。本研究的目的是评估一种用于IMD无线短程传输系统的新型密封天线，由于天线外壳的高度密封性限制了人体组织环境对传输信号的影响，该天线将确保可靠的长期运行。对三种不同的原型进行了实验测试，以评估在空气中以及通过模拟人体胸部的混合物进行传输时最有效的天线配置。还进行了进一步的测试，以评估连接到IMD的电导管对传输信号的影响。结果表明，密封天线在空气中以及通过人体胸部模拟器都能保证良好的无线传输。结果还表明，电导管的存在会根据其相对于遥测电路的位置影响传输的有效辐射功率（ERP）。在不超过规则规定的限制的情况下控制ERP的增加以及优化天线与发射器之间的调谐，都可以使用所提出的新型密封天线确保可靠的短程传输（几米）。
