Creation and characterization of normal myocardial perfusion imaging databases using the IQ·SPECT system

Area of Science:

• Nuclear Cardiology
• Medical Imaging Physics

Background:

• Short-time single-photon emission-computed tomography (SPECT) imaging is now feasible with IQ·SPECT technology.
• Thallium-201 (²⁰¹Tl) is a radiotracer used for myocardial perfusion imaging.

Purpose of the Study:

• To establish normal databases (NDBs) for ²⁰¹Tl myocardial perfusion imaging using IQ·SPECT.
• To characterize the distribution patterns of myocardial perfusion in normal individuals using IQ·SPECT.

Main Methods:

• Retrospective analysis of 159 patients with low likelihood of cardiac disease.
• Acquisition of short-time ²⁰¹Tl myocardial perfusion IQ·SPECT images with or without attenuation and scatter correction (ACSC), in supine and prone positions.
• Calculation of mean myocardial counts using 17-segment polar maps to derive NDBs.

Main Results:

• Significant differences were observed between uncorrected supine and prone NDBs.
• Differences were noted between IQ·SPECT NDBs (with/without ACSC) and conventional SPECT NDBs.
• Apical low counts, potentially due to myocardial thinning, were identified in specific segments of supine IQ·SPECT NDBs with ACSC.

Conclusions:

• Understanding normal distribution patterns in IQ·SPECT is crucial for interpreting cardiac imaging findings.
• The generated NDBs facilitate quantitative analysis of myocardial perfusion in patients with coronary artery disease (CAD).
• Variations in NDBs based on imaging acquisition (position, ACSC) are significant and must be considered.