The purpose of this document is to assist nuclear medicine practitioners in recommending, performing, interpreting, and reporting the results of gated equilibrium radionuclide angiocardiography (ERNA).

The benefits of four-dimensional computed tomography (4D CT) are limited by the presence of artifacts that remain difficult to quantify. A correlation-based metric previously proposed for ciné 4D CT artifact identification was further validated as an independent artifact evaluator by using a novel qualitative assessment featuring a group of observers reaching a consensus decision on artifact location and magnitude. The consensus group evaluated ten ciné 4D CT scans for artifacts over each breathing phase of coronal lung views assuming one artifact per couch location. Each artifact was assigned a magnitude score of 1-5, 1 indicating lowest severity and 5 indicating highest severity. Consensus group results served as the ground truth for assessment of the correlation metric. The ten patients were split into two cohorts; cohort 1 generated an artifact identification threshold derived from receiver operating characteristic analysis using the Youden Index, while cohort 2 generated sensitivity and specificity values from application of the artifact threshold. The Pearson correlation coefficient was calculated between the correlation metric values and the consensus group scores for both cohorts. The average sensitivity and specificity values found with application of the artifact threshold were 0.703 and 0.476, respectively. The correlation coefficients of artifact magnitudes for cohort 1 and 2 were 0.80 and 0.61, respectively, (p < 0.001 for both); these correlation coefficients included a few scans with only two of the five possible magnitude scores. Artifact incidence was associated with breathing phase (p < 0.002), with presentation less likely near maximum exhale. Overall, the correlation metric allowed accurate and automated artifact identification. The consensus group evaluation resulted in efficient qualitative scoring, reduced interobserver variation, and provided consistent identification of artifact location and magnitudes.

The incorporation of positron emission tomography-computed tomography (PET-CT) into oncological imaging has expanded rapidly since the hybrid scanners were introduced approximately 10 years ago. PET-CT is becoming the standard of practice for the imaging diagnosis and staging of most cancers. Since its introduction, hardware-registered PET and CT images produced by a PET-CT scan were recognized as valuable not only for detection, staging and restaging applications but also for optimizing radiation treatment planning. Even before the introduction of PET-CT, the value of metabolic imaging with the use of FDG PET was recognized as a potentially powerful means of assessing response to various therapies, particularly chemotherapy regimens. To better understand the optimal use of PET-CT in radiation therapy planning and the role of PET-CT in assessing response to therapy, we invited experts from various disciplines to participate in focus group meetings that took place in 2009 and 2010. The Symposia focused on the use of PET-CT imaging in radiation therapy planning (2009) and the use of PET-CT in therapy response assessment (2010). This article will summarize areas of consensus reached by the group regarding many of the discussion topics. The consensus summaries covered in this article are meant to provide direction for future discussions on how to improve the application of this hybrid modality to optimize patient care.