A comparison between upright and supine myocardial perfusion imaging with attenuation correction

Area of Science:

• Nuclear Medicine
• Cardiovascular Imaging
• Medical Imaging Technology

Background:

• The Digirad Cardius XACT system provides upright myocardial perfusion imaging (MPI) with low-dose computed tomography for attenuation correction (AC).
• Supine MPI on a GE Infinia Hawkeye is a common alternative for assessing myocardial perfusion.

Purpose of the Study:

• To compare patient acceptability and image appearance between upright (XACT) and supine (Infinia) MPI.
• To evaluate the impact of attenuation correction (AC) on image quality and diagnostic consistency in upright MPI.

Main Methods:

• 47 patients underwent rest and stress MPI on both XACT and Infinia systems.
• Non-AC and AC bullseye plots were analyzed, and uptake scores were recorded.
• Patient comfort was assessed using a questionnaire, and studies were reported by an experienced observer.

Main Results:

• Perfusion patterns differed significantly between upright and supine non-AC images, with sex-based distinctions.
• Upright and supine AC images showed similar perfusion patterns for both sexes, despite some reporting discrepancies.
• Patients strongly preferred the upright imaging system.

Conclusions:

• Attenuation correction (AC) effectively addresses soft-tissue and diaphragmatic attenuation differences between upright and supine MPI.
• Clinicians must remain aware of potential artifacts associated with both upright and supine imaging techniques.