Implementation and CT sampling characterization of a third-generation SPECT-CT system for dedicated breast imaging

Area of Science:

• Medical Imaging
• Radiological Physics

Background:

• Previous breast imaging systems using cone beam computed tomography (CT) and single-photon emission computed tomography (SPECT) had limitations in complex acquisition trajectories.
• Fully three-dimensional (3-D) SPECT systems offered insights into the chest wall and entire breast volume.
• Cone beam CT (CBCT) systems with polar tilting improved sampling near the chest wall and reduced artifacts.

Purpose of the Study:

• To develop and present a single hybrid SPECT-CT system capable of independent complex trajectories for breast imaging.
• To evaluate the practical implementation and preliminary results of the CT component of the hybrid system.
• To demonstrate the system's ability to achieve spherical trajectories for comprehensive breast imaging.

Main Methods:

• A hybrid SPECT-CT system was designed with SPECT nested inside the CT gantry, both capable of independent complex trajectories.
• The system utilized a rotation stage with combined polar and azimuthal motions for spherical trajectory acquisition.
• Six trajectories were employed for evaluating the tilt-capable CT system's performance.

Main Results:

• The developed hybrid system achieved precise polar tilt angles with minimal positioning error and no hysteresis.
• Initial imaging results showed that off-axis projection views enhanced sampling completeness and attenuation value recovery.
• Reconstructed images demonstrated marked improvements, indicating superior diagnostic potential.

Conclusions:

• The hybrid SPECT-CT system offers a versatile platform for advanced breast imaging.
• The system's capability for complex trajectories and improved reconstructions holds promise for diagnostic and therapeutic applications.
• This technology could significantly advance breast cancer detection and treatment monitoring.