The Optical Sensors research group at SiliconTech is working on developing a cardiac vibration monitoring probe, belonging to the group of non-invasive optical sensors, and its associated sensor system to solve issues related to cardiac monitoring in MRI environments.
In general, there are three types of Optical Sensors: (1) non-invasive sensors, which come into direct contact with the human skin; (2) minimally-invasive sensors, which are used for measurements carried out in body cavities; and (3) invasive sensors, which are used for measurements made inside organs or in the bloodstream (intravascular).
Desirable characteristic features of Optical Sensors include their independence from an active power supply and a high immunity to electromagnetic interference. Due to these attributes, Optical Sensors can be used with other electronic equipment without generating electric noise that may compromise the quality of vital sign monitoring and potentially lead to patient safety concerns.
Optical Sensors are gaining more popularity due to their flexibility, improved functionality, and reliability. The very small dimensions of optical fibers allow them to be encapsulated inside very thin catheters and injection needles, thereby enabling localized and minimally-invasive monitoring.
Biocompatibility is a very important consideration in the acquisition and evaluation of high quality data from sensors coming into contact with living tissue. As Optical Sensors are biocompatible and do not influence the patient’s body in any major way, they offer a great level of patient comfort during vital sign monitoring.
Monitoring of physiological parameters during MRI is recommended in neonatal and pediatric patients, persons with implanted artificial pacemakers, disabled persons, persons with mental disorders, patients developing reactions to contrast mediums, being in coma or administered local anesthesia.
Commonly used equipment and sensors used for patient monitoring of heart rate, EKG and respiration rate that employ electronics cannot be used within the high magnetic field environment found within an MRI machine.
Few other aspects of the proposed system are also required to be addressed to solve issues related to cardiac monitoring in MRI environments.
In this limited space, we do not intend to compare our system with other existing sensors. The comprehensive characterization of our novel sensor system and its comparison with other existing sensors will be the focus of our future articles with detailed signal processing.