Performance evaluation of a pixellated Ge Compton camera

Area of Science:

• Medical Physics
• Nuclear Instrumentation
• High Energy Physics

Background:

• Conventional gamma cameras face limitations in certain medical imaging applications.
• Compton cameras offer potential advantages in sensitivity and spatial resolution.
• High purity germanium (HPGe) detectors provide excellent energy resolution for gamma-ray detection.

Purpose of the Study:

• To develop and evaluate a novel high purity germanium (HPGe) Compton camera for medical applications.
• To assess the performance characteristics of a prototype HPGe Compton camera.
• To demonstrate the imaging capabilities of the Compton camera with various test objects.

Main Methods:

• Construction of a Compton camera with two pixellated HPGe detector planes (scatter and absorption).
• Utilized a multiple-view technique to simulate a full camera configuration due to limited readout modules.
• Acquired images of point sources, a ring source, and a Perspex phantom using a 662 keV gamma-ray source.

Main Results:

• The HPGe Compton camera consists of 177 pixels (152 scatter, 25 absorption) with specific dimensions.
• Achieved a measured angular resolution of 9.4° ± 0.4° for a 662 keV gamma-ray source at 3 cm distance.
• Successfully imaged various test objects, demonstrating the camera's potential for medical applications.

Conclusions:

• The developed HPGe Compton camera shows promise for medical imaging, offering potential advantages over conventional systems.
• The prototype demonstrated viable imaging capabilities and acceptable angular resolution.
• Further development with a full pixel arrangement is expected to enhance performance.