Test Results for a Dual-detector Gamma Camera with a Variable Angle Slant-hole Collimator

We have developed a computer controlled motorized variable angle slant-hole (VASH) collimator for a molecular breast imaging (MBI) detector. The VASH collimator enables the acquisition of multiple projections without detector movement and provides limited 3D image reconstruction. The range of collimation angle of the current VASH collimator is 28 degrees for each direction which is 15 % of 360 degree full scan. Due to this limited angular sampling range, vertical image resolution is poor compare to horizontal image resolution. To minimize this drawback, we are developing a dual-detector system using two VASH collimators. The dual-detector system, placed at the top and bottom of the imaging target, is expected to have more sensitivity and better resolution especially in the vertical direction. Initial tests were performed with the current VASH gamma camera and a second virtual camera to simulate a dual-detector system performance. Test results show significant improvement in terms of image resolution and quality.