Related Experiment Video
Updated: Jun 5, 2026
Phase-Resolved Functional Lung MRI for Pulmonary Ventilation and Perfusion (V/Q) Assessment
Published on: August 9, 2024
Wide-beam reconstruction half-time SPECT improves diagnostic certainty and preserves normalcy and accuracy: a
Regina S Druz1, Lawrence M Phillips, Michelle Chugkowski
1Department of Cardiology, North Shore University Hospital, Manhasset, NY 11030, USA. rdruzmd@aol.com
Background:
Filtered back-projection (FBP) has been a standard in SPECT imaging. Newer iterative reconstruction algorithms have been shown to improve image quality and shorten acquisition time by taking into account statistical nature of raw data and using resolution recovery (RR). Wide-beam reconstruction (WBR) is an iterative algorithm with RR and adaptive noise control. We prospectively investigated outcome of WBR half-time SPECT on diagnostic certainty, accuracy and normalcy by quantitative perfusion analysis in comparison to full-time FBP images.
Methods:
434 patients underwent rest (201)Tl/stress (99m)Tc-sestamibi full-time (20 s/stop, FBP) followed by a half-time (10 s/stop, WBR) SPECT. 34 patients underwent an angiogram within 90 days of SPECT. Diagnostic certainty was based on summed stress scores (SSS, 5-point/17 segments): normal if SSS ≤ 1, equivocal if SSS = 2-3, and abnormal if SSS ≥ 4. Perfusion defects were normalized to a percent of total myocardium, and expressed as %LV = defect SSS/maximal SSS × 100% with maximal SSS of 28 for left anterior descending (LAD), and of 20 for right coronary (RCA) and left circumflex (LCX). Change in %LV (Δ%LV = %LV FBP - %LV WBR) was evaluated for diagnostically discordant versus concordant scans.
Results:
SSS and %LV demonstrated very good correlation. There were significantly fewer equivocal scans with WBR (38 vs 151 FBP, P < .0001). Most discordant scans were equivocal FBP SPECT becoming normal with WBR (123/151). Δ%LV(LAD) for discordant studies was greater for women (5.4% ± 4.2%, P < .001), while Δ%LV(RCA,LCX) (4.4% ± 5.1%, P < .001; 1.2% ± 5.0%, P = .04) were greater for men. Normalcy rate was 91.4% for FBP and WBR with more definitely normal WBR studies (84.5% vs 43.9% for FBP, P < .0001). There were no differences in sensitivity (FBP 84.2%, WBR 81.6%), specificity (FBP 54.6%, WBR 63.6%), and accuracy (FBP, WBR 77.6%).
Conclusion:
Quantitative perfusion analysis suggests that adaptive noise control with WBR improves uniformity of myocardium comparing to FBP techniques, and results in improved diagnostic certainty while preserving normalcy and accuracy.
Related Concept Videos
01:17Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...