Related Experiment Video
Updated: Jun 18, 2026
High-Resolution Cardiac Positron Emission Tomography/Computed Tomography for Small Animals
Published on: December 16, 2022
New reconstruction algorithm allows shortened acquisition time for myocardial perfusion SPECT
Ines Valenta1, Valerie Treyer, Lars Husmann
1Cardiac Imaging, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland.
Purpose:
Shortening scan time and/or reducing radiation dose at maintained image quality are the main issues of the current research in radionuclide myocardial perfusion imaging (MPI). We aimed to validate a new iterative reconstruction (IR) algorithm for SPECT MPI allowing shortened acquisition time (HALF time) while maintaining image quality vs. standard full time acquisition (FULL time).
Methods:
In this study, 50 patients, referred for evaluation of known or suspected coronary artery disease by SPECT MPI using 99mTc-Tetrofosmin, underwent 1-day adenosine stress 300 MBq/rest 900 MBq protocol with standard (stress 15 min/rest 15 min FULL time) immediately followed by short emission scan (stress 9 min/rest 7 min HALF time) on a Ventri SPECT camera (GE Healthcare). FULL time scans were processed with IR, short scans were additionally processed with a recently developed software algorithm for HALF time emission scans. All reconstructions were subsequently analyzed using commercially available software (QPS/QGS, Cedars Medical Sinai) with/without X-ray based attenuation correction (AC). Uptake values (percent of maximum) were compared by regression and Bland-Altman (BA) analysis in a 20-segment model.
Results:
HALF scans yielded a 96% readout and 100% clinical diagnosis concordance compared to FULL. Correlation for uptake in each segment (n = 1,000) was r = 0.87at stress (p < 0.001) and r = 0.89 at rest (p < 0.001) with respective BA limits of agreement of -11% to 10% and -12% to 11%. After AC similar correlation (r = 0.82, rest; r = 0.80, stress, both p < 0.001) and BA limits were found (-12% to 10%; -13% to 12%).
Conclusion:
With the new IR algorithm, SPECT MPI can be acquired at half of the scan time without compromising image quality, resulting in an excellent agreement with FULL time scans regarding to uptake and clinical conclusion.
Insights
New iterative reconstruction for SPECT MPI halves scan time without sacrificing image quality. This method maintains excellent agreement with full-time scans for uptake and clinical diagnosis, improving efficiency in cardiac imaging.
Area of Science:
- Nuclear Medicine
- Cardiovascular Imaging
- Medical Imaging Technology
Background:
- Current research in radionuclide myocardial perfusion imaging (MPI) focuses on reducing scan time and radiation dose while preserving image quality.
- Iterative reconstruction (IR) algorithms are key to improving SPECT MPI efficiency.
Purpose of the Study:
- To validate a novel iterative reconstruction (IR) algorithm for SPECT MPI.
- To assess if shortened acquisition time (HALF time) maintains image quality compared to standard full-time acquisition (FULL time).
Main Methods:
- 50 patients with suspected coronary artery disease underwent SPECT MPI using 99mTc-Tetrofosmin.
- Standard (FULL time: 15 min stress/15 min rest) and shortened (HALF time: 9 min stress/7 min rest) scans were acquired sequentially.
- Scans were reconstructed using IR, with HALF time scans processed by a dedicated algorithm, and analyzed with/without attenuation correction (AC).
Main Results:
- HALF time scans achieved 96% readout and 100% clinical diagnosis concordance with FULL time scans.
- High correlations for myocardial uptake were observed (stress r=0.87, rest r=0.89) with narrow Bland-Altman limits.
- Similar correlations and limits were found after X-ray based attenuation correction.
Conclusions:
- The new IR algorithm enables SPECT MPI acquisition in half the standard scan time.
- Image quality and clinical diagnostic accuracy are maintained with the shortened protocol.
- This validates the IR algorithm for efficient and reliable SPECT MPI.
