Sensitivity and specificity are statistical measures of the performance of a diagnostic imaging test. Sensitivity, which is also referred to as the true positive rate, is a proportionate measure of patients who are accurately identified as having a specific condition.

Conversely, specificity, also called the true negative rate, measures the proportion of patients who are accurately identified as not having the same condition. In other words, sensitivity quantifies the avoidance of false negatives as specificity does the same for false positives.

How does attenuation correction help?

Attenuation correction is a major contributor to both specificity and sensitivity. By reducing attenuation, the images will be more uniform, allow for higher reading and diagnostic confidence and help decrease the likelihood of false positives. It offers greater support to the reading physician that normal is indeed normal, without question.

The immeasurable value of attenuation correction is the reduced number of patients who could potentially undergo additional unnecessary procedures because their images were inconclusive or indicated a positive result, albeit false. Ultimately, the optimized specificity brought about through attenuation correction should not be discounted. It is the most accurate way to get a “normal” scan.

In the gradual shift toward stress-only Myocardial Perfusion Imaging protocols, specificity leads to greater accuracy, substantially impacts patient care and the growing concern surrounding radiation burden. Attenuation correction can positively influence all of these aspects.