Physical and subjective evaluation of a three-detector (TRIAD 88) SPECT system

Area of Science:

• Nuclear Medicine
• Medical Imaging Physics

Background:

• The TRIAD 88 is a whole-body SPECT system with variable cylindrical FOV.
• It is designed for both brain and body organ imaging.

Purpose of the Study:

• To assess the physical and clinical performance of the TRIAD 88 SPECT system.
• To compare two parallel hole collimator types: LEUR_PAR and LEHR_PAR.

Main Methods:

• Evaluated physical indices: contrast-detail curves, LSFs, sensitivity, energy resolution, uniformity.
• Used Carlson phantom, Hoffman brain phantom, and clinical brain images for subjective comparison.
• Analyzed display characteristics using H & D curves.

Main Results:

• LEUR_PAR collimator had 58% of the sensitivity of LEHR_PAR.
• Planar spatial resolution differed by 14% between collimators.
• No statistical difference in lesion detectability on planar contrast-detail curves, but improved performance with LEUR_PAR on phantom and clinical SPECT images.
• Consistent performance across the three detector heads.

Conclusions:

• The TRIAD 88 system demonstrates good performance for brain and body imaging.
• While sensitivity differs, the LEUR_PAR collimator shows improved image quality in phantom and clinical SPECT imaging.
• The system exhibits consistent performance among its three detector heads.