Sensor Systems for Healthcare

The rapid growth of wearable sensor and embedded system technologies has enabled remote and continuous monitoring of patients’ physical conditions for efficient healthcare services. Pressure ulcers (PU) are a major problem for people with spinal cord injuries (SCI). Statistics show that more than 50% of people with SCI experience pressure ulcers during their lifetimes. PUs are likely to develop when there is excessive pressure on the body tissue for lengthy durations. Persons with SCI, who sit in wheelchairs for many hours per day, are at high risk of developing PUs in their buttock areas. To prevent pressure ulcers, persons who usually spend long time sitting in wheelchairs are advised to perform regular pressure reliefs in their daily life.

We have proposed a robust pressure relief monitoring system that can achieve long-term monitoring of wheelchair users’ pressure relief behaviors. The system employs several sensors to measure the pressure on a wheelchair cushion, and it can automatically detect the time and duration of pressure relief activities. Statistical results generated by this system could help clinicians to quantify the risk factors of pressure ulcer formation. For the treatment of pressure ulcers, we have designed and developed a low-cost, handheld, and non-contact system to measure the area and depth of a wound. The camera sensor on a smartphone is used to capture an image of a wound, and meanwhile, structured lights with known positions are projected on the wound surface to assist the measurement. Algorithms for measuring the area and depth of the wound are developed based on projection geometry and image processing techniques. Test results in clinical environments show that this system achieves good accuracy and repeatability.
 

Related Publications

1. R. Dai, S. Sonenblum, and S. Sprigle, "A Robust Wheelchair Pressure Relief Monitoring System", International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Aug. 2012.