Multi-element Linear Array of Silicon Detectors for Imaging Beta Emitting Compounds in the Coronary Arteries

Coronary artery disease (CAD) is the leading cause of death in most developed countries. A large portion of CAD is caused by rupture of unstable plaque, which is not detectable by current diagnostic methods. By labeling the unstable plaque with beta emitting radioisotopes, it is possible to detect these plaques with a very narrow in situ detector system. Our intra-vascular detector system is an imaging device, consisting of several silicon detectors mounted on a flexible PC-board inside of a 1.6 mm diameter catheter. The catheter shields the detectors from outside light and enables the device to be guided to the coronary arteries during an angiography session. Each silicon detector consists of a linear array of 20 square pixels, with pixel dimensions of 0.45 mm × 0.45 mm. The silicon arrays are stacked to create a one-dimensional imaging device. The read-out employs a resistor network and uses standard Anger logic to correctly position beta events along the array. In this way, the tracer distribution in the coronary arteries can be accurately determined.