PYP Quantitative Uptake Index (QUI) Calculator
- PYP Quantitative Uptake Index (QUI): Explanation and Clinical Context
The PYP Quantitative Uptake Index (QUI) is a ratio of the radiotracer counts measured in the myocardial region of interest (ROI) to the contralateral chest ROI during 99mTc-Pyrophosphate (PYP) scintigraphy.
It is used to quantify myocardial uptake and improve the diagnostic accuracy for transthyretin cardiac amyloidosis (ATTR-CA).
A higher QUI value indicates more significant myocardial radiotracer accumulation. Typically, a QUI >1.5 is suggestive of clinically relevant myocardial amyloid deposition.
This index provides a reproducible, objective metric that can supplement visual scoring (Perugini grading) in clinical practice, enabling better risk stratification, disease monitoring, and follow-up of patients with suspected ATTR-CA.
Reference:
Falk RH, et al. "Noninvasive Evaluation of Cardiac Amyloidosis Using 99mTc-Pyrophosphate Scintigraphy." Circulation. 2013;127:920–929. doi:10.1161/CIRCULATIONAHA.112.000433
QUALITY & SAFETY
Report an issue
Your feedback helps us improve the reliability and usability of this clinical tool.
Please describe the issue clearly. For calculation concerns, include the input values and expected result where possible.