"We looked at other processors, but having memory and I/O, and a dedicated C compiler with examples made Rabbit the right choice" - Martin Brown, Best Medical Canada

One of the most effective methods to combat cancer and tumors is radiation therapy. Along with the benefits there also exists a significant level of risk, since too much radioactive exposure can cause new formations of cancer or even lead to death. In order to protect from over-exposure, a subspecialty called dosimetry calculates the radiation level of in a mass or tissue. Measurements are made with a device called MOSFET (Metal Oxide Field Effect Transistor) dosimeter. Dosimeters have become widely popular for clinical use, especially with radiotherapy. With the help of the RCM3100 RabbitCore, Best Medical Canada is taking dosimetry to a whole new level.

Martin Brown, an Engineering Technologist at Best Medical Canada brings insight into the innovations and improvements of dosimeter technology. Traditional MOSFET dosimeter verification systems have typically consisted of large machines with numerous wires and power supplies, all of which are connected to the wall. Brown explained that Best Medical Canada identified a market in which the mobileMOSFET would be ideal, focusing on portability and ease of use.

"We felt that the market would benefit from a smaller battery powered wireless product with minimal size and cables," stated Brown.

The mobileMOSFET is a wireless dose verification system, which is a portable, easy-to-use, and seamlessly integrated system. The system minimizes QA time, making the device ideal for a busy radiotherapy center. Best Medical Canada's mobileMOSFET system is entirely software driven, allowing for remote control of multiple systems from one PC. The system consists of Remote Monitoring Dose Verification Software, a wall-mounted Bluetooth® Wireless Transceiver, and a small Reader Module that acts as a channel between the MOSFET and software.

MOSFET dosimeters placed on the patient connect to a reader module that transmits data to a PC via a Bluetooth transceiver. As a patient is irradiated, the MOSFET sensors measure the level of exposure and the reader module captures the readings. The reader module, which contains the RCM3100, processes the information and sends the information to a PC via Bluetooth.

Multiple wireless readers allow multiple patients to be monitored from one PC. The verification system allows health professionals to treat more patients with better accuracy, using real-time data. More traditional dosimeter systems require a level of maintenance due to the extra cabling that must be connected and reconnected as well as the reduction of mobility in the treatment room.

In the heart of the mobileMOSFET reader module resides an RCM3100 RabbitCore® module, the main processing unit in the reader module. When the PC requests information from the sensors, the RCM3100 monitors the request, turning on power supplies and appropriate analog switches for configuration. The I/O pins check whether any sensors are connected. The RCM3100 processes the gathered information from the dosimeters and sends the data back to the main PC. Brown pointed out medical equipment must meet certain criteria.

"All of our medical products need to be rigorously tested to comply with European CE regulations. A large concern to our design engineers was the EMI emissions and susceptibility tests," Brown said.

He further explained that for a time the weakest link in the system was the microprocessor, though after seeing a Rabbit advertisement in a magazine, they felt it was worth a try.

"Sample code to reduce time-to-market and great EMI performance was very beneficial," said Brown.

Not only did Dynamic C® and the sample programs help Best Medical Canada to bring mobileMOSFET to market quickly, but the microprocessor's low EMI also fit their strict requirements.

"The ability to step through the software in a core module while it is actively installed in a target board has helped a great deal in developing code," stated Brown. "We looked at other processors, but having memory and I/O, and a dedicated C compiler with examples made Rabbit the right choice."

Rabbit once again provided a product that truly meets the needs of the customer. The RCM3100 allowed Best Medical Canada to bring dosimetry to the next level, helping medical professionals provide patients with the highest quality of care.

Best Medical Canada