Diagnostic impact of SPECT image display on assessment of obstructive coronary artery disease

Area of Science:

• Cardiology
• Medical Imaging
• Diagnostic Nuclear Medicine

Background:

• Diagnostic assessment of myocardial perfusion is crucial for managing suspected coronary artery disease (CAD).
• Various image displays exist for single photon emission computed tomography (SPECT) interpretation.
• The impact of different SPECT image displays on interpretation accuracy is not well-established.

Purpose of the Study:

• To investigate the effect of different image display types (color vs. gray) on SPECT interpretation for CAD.
• To determine if diagnostic performance can be optimized by adjusting interpretation criteria based on display type.

Main Methods:

• 183 patients undergoing SPECT were studied, including those referred for angiography and low-risk individuals.
• Studies were visually interpreted using both color and gray images, with readers blinded to the other display.
• A summed stress score (SSS) of 4 or greater was initially used as the criterion for abnormal findings.

Main Results:

• The prevalence of abnormal SPECT findings was higher with gray images (54%) compared to color images (48%) using a uniform criterion (SSS ≥ 4).
• Color images showed equivalent sensitivity (79% vs. 82%) but improved specificity for global and vessel-specific CAD.
• Adjusting the criterion for gray images to SSS ≥ 5 resulted in equivalent sensitivity and specificity compared to color images.

Conclusions:

• SPECT interpretation accuracy for CAD varies depending on the image display used.
• Differences in perfusion defect severity between color and gray displays influence interpretation.
• Adjusting abnormality criteria for gray images to account for minor increases in defect severity achieves equivalent diagnostic performance to color displays.