SPECT instrumentation: performance, lesion detection, and recent innovations.

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Radiological Physics

Background:

• Single photon emission computed tomography (SPECT) imaging demands higher gamma camera performance than planar imaging.
• Inadequate camera specifications can lead to significant artifacts in SPECT images.
• Continuous advancements in hardware and software are crucial for optimal SPECT performance.

Purpose of the Study:

• To enhance lesion detection capabilities in SPECT imaging.
• To investigate factors influencing contrast and image quality in SPECT.
• To explore methods for artifact reduction and improved resolution in SPECT.

Main Methods:

• Evaluation of camera performance, including field nonuniformity and its correction.
• Application of attenuation and scatter correction techniques.
• Assessment of novel collimator designs (cast, long bore, converging fan beam, astigmatic) and noncircular orbits.
• Exploration of simultaneous image collection with offpeak energy windows for scatter subtraction.

Main Results:

• Attenuation correction shows minimal effect on contrast for Tc-99m despite visual improvement.
• Scattered photons are a primary cause of contrast loss; offpeak windows and scatter subtraction show promise.
• New collimator designs and noncircular orbits can improve SPECT resolution and sensitivity, though they present challenges.

Conclusions:

• Optimizing SPECT imaging necessitates rigorous quality control and advanced correction strategies.
• Developments in hardware (collimators) and software (scatter correction) are key to overcoming SPECT limitations.
• Further research into novel SPECT camera systems aims to address complexity and cost barriers.