Observer repeatability and interscan reproducibility of 18F-sodium fluoride coronary microcalcification activity (Preprint)

2020 ◽  
Author(s):  
Piotr Slomka

UNSTRUCTURED Background (words 199/200) We aimed to establish the observer repeatability and interscan reproducibility of coronary 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) uptake using a novel semi-automated approach, coronary microcalcification activity (CMA). Methods Patients with multivessel coronary artery disease underwent repeated hybrid PET and computed tomography angiography (CTA) imaging (PET/CTA). CMA was defined as the integrated standardized uptake values (SUV) in the entire coronary tree exceeding 2 standard deviations above the background SUV. Coefficients of repeatability between the same observer (intraobserver repeatability), between 2 observers (interobserver repeatability) and coefficient of reproducibility between 2 scans (interscan reproducibility), were determined at both vessel and patient level. Results In 19 patients, CMA was assessed twice in 43 coronary vessels on two PET/CT scans performed 12±5 days apart. There was excellent intraclass correlation on a per-vessel and per-patient level for intraobserver and interobserver repeatability as well as interscan reproducibility (≥0.991 for all). There was 100% intraobserver, interobserver and interscan agreement for the presence (CMA>0) or absence (CMA=0) of coronary18F-NaF uptake. Mean CMA was 3.12±0.62 with coefficients of repeatability of ≤10% for all measures: intraobserver 0.24 and 0.22, interobserver 0.30 and 0.29 and interscan 0.33 and 0.32 at a per-vessel and per-patient level respectively. Conclusions CMA is a repeatable and reproducible global measure of coronary atherosclerotic activity.

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Martina Marinelli ◽  
Vincenzo Positano ◽  
Francesco Tucci ◽  
Danilo Neglia ◽  
Luigi Landini

Hybrid PET/CT scanners can simultaneously visualize coronary artery disease as revealed by computed tomography (CT) and myocardial perfusion as measured by positron emission tomography (PET). Manual registration is usually required in clinical practice to compensate spatial mismatch between datasets. In this paper, we present a registration algorithm that is able to automatically align PET/CT cardiac images. The algorithm bases on mutual information (MI) as registration metric and on genetic algorithm as optimization method. A multiresolution approach was used to optimize the processing time. The algorithm was tested on computerized models of volumetric PET/CT cardiac data and on real PET/CT datasets. The proposed automatic registration algorithm smoothes the pattern of the MI and allows it to reach the global maximum of the similarity function. The implemented method also allows the definition of the correct spatial transformation that matches both synthetic and real PET and CT volumetric datasets.


2020 ◽  
Vol 93 (1113) ◽  
pp. 20190797 ◽  
Author(s):  
Jacek Kwiecinski ◽  
Piotr J Slomka ◽  
Marc R Dweck ◽  
David E Newby ◽  
Daniel S Berman

Positron emission tomography (PET) with 18F-sodium fluoride (18F-NaF) has emerged as a promising non-invasive imaging modality to identify high-risk and ruptured atherosclerotic plaques. By visualizing microcalcification, 18F-NaF PET holds clinical promise in refining how we evaluate coronary artery disease, shifting our focus from assessing disease burden to atherosclerosis activity. In this review, we provide an overview of studies that have utilized 18F-NaF PET for imaging atherosclerosis. We discuss the associations between traditional coronary artery disease measures (risk factors) and 18F-NaF plaque activity. We also present the data on the histological validation as well as show how 18F-NaF uptake is associated with plaque morphology on intravascular and CT imaging. Finally, we discuss the technical challenges associated with 18F-NaF coronary PET highlighting recent advances in this area.


2012 ◽  
Vol 63 (4) ◽  
pp. 289-293 ◽  
Author(s):  
Yung H. Kao ◽  
Siew S. Lim ◽  
Seng C. Ong ◽  
Ajit K. Padhy

Introduction To determine the incidence of fluorine-18-fluorodeoxyglucose (FDG) avid thyroid incidentalomas detected on positron emission tomography (PET) with integrated computed tomography (CT), and correlate the FDG–PET-CT findings to cytology. Methods A total of 942 FDG–PET-CT reports were retrospectively reviewed. Patients with FDG-avid thyroid incidentalomas were further reviewed for correlative cytology. Results The incidence of FDG-avid thyroid incidentalomas is 2.2%. Thyroid malignancies were identified in 3 of 6 patients who underwent cytologic correlation, with a positive predictive value of 50% (95% confidence interval, 14%-86%). The mean maximum standardized uptake values of benign and malignant FDG-avid thyroid incidentalomas were 5.6 and 6.6, respectively. Conclusion A FDG-avid thyroid incidentaloma may predict underlying malignancy. Cytologic assessment should be considered for FDG-avid thyroid incidentalomas.


2021 ◽  
Author(s):  
Wanwan Wen ◽  
Mingxin Gao ◽  
Mingkai Yun ◽  
Jingjing Meng ◽  
Ziwei Zhu ◽  
...  

Abstract Purpose: 18F-Sodium fluoride (18F-NaF) positron emission tomography (PET) is a novel approach to detect and quantify microcalcification in atherosclerosis. Peri-coronary adipose tissue (PCAT) is associated with vascular inflammation and high-risk atherosclerotic plaque. We aimed to assess the association between coronary 18F-NaF uptake with pro-atherosclerosis factors in patients with multivessel coronary artery disease (CAD) and to explore the systematic vascular osteogenesis in the coronary artery and aorta in these patients. Methods: Patients with multivessel CAD prospectively underwent cardiac computed tomography (CT) and 18F-NaF PET/CT. PCAT density was measured in the coronary artery and the average PCAT value was calculated from the three coronary arteries in each patient. 18F-NaF tissue-to-blood ratios (TBR) in the coronary artery (TBRCoronary) and aorta (TBRAorta) were calculated. Correlations between coronary 18F-NaF uptake with PCAT density, coronary artery calcium (CAC) burden, CAD risk factors, serum biomarkers, and aortic 18F-NaF uptake were evaluated, respectively. Patients were categorized by a median of TBRCoronary 2.49. Results: 100 multivessel CAD patients (64.00 [57.00 - 67.75] years; 76 men) were prospectively recruited. 6010 active aortic segments (TBR ≥ 1.6) were identified. TBRCoronary was significantly associated with the PCAT density (r = 0.56, p < 0.001) and CAC score (r = 0.45, p < 0.001). TBRCoronary was also significantly associated with the TBRAorta (r = 0.42, p < 0.001). In addition, patients with higher TBRCoronary showed elevated PCAT density (-75.89[-79.07 - -70.06] vs -84.54[-90.21 - -79.46]; p < 0.001) and CAC score (1495.20[619.80 - 2225.40] vs 273.75[116.73 - 1198.18]; p < 0.001) in comparsion patients with lower TBRCoronary. TBRCoronary was correlated with the age (r = 0.24, p = 0.019) and the serum troponin I levels (r = 0.22, p = 0.039). There were no significant correlations between TBRCoronary with other conventional CAD risk factors and other serum biomarkers.Conclusion: Coronary 18F-NaF uptake was correlated with the PCAT density. A significant correlation between 18F-NaF uptake in the coronary artery and aorta might indicate a systematic vascular osteogenesis in patients with multivessel CAD.


2021 ◽  
Vol 11 ◽  
Author(s):  
Hao Wang ◽  
Wenwei Zhu ◽  
Shuhua Ren ◽  
Yanyan Kong ◽  
Qi Huang ◽  
...  

BackgroundFibroblast activation protein (FAP) is commonly expressed in activated stromal fibroblasts in various epithelial tumours. Recently, 68Ga-FAPI-04 has been used for tumour imaging in positron emission tomography/computed tomography (PET/CT). This study aimed to compare the diagnostic performances of 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT in hepatocellular carcinoma (HCC), and to assess factors associated with 68Ga-FAPI-04 uptake in HCC.Materials and MethodsTwenty-nine patients with suspiciously HCC who received both 18F-FDG and 68Ga-FAPI-04 PET/CT were included in this retrospective study. The results were interpreted by two experienced nuclear medicine physicians independently. The maximum and mean standardized uptake values (SUVmax and SUVmean) were measured in the lesions and liver background, respectively. The tumour-to-background ratio (TBR) was then calculated as lesion’s SUVmax divided by background SUVmean.ResultsA total of 35 intrahepatic lesions in 25 patients with HCC were finally involved in the statistical analysis. 68Ga-FAPI-04 PET/CT showed a higher sensitivity than 18F-FDG PET/CT in detecting intrahepatic HCC lesions (85.7% vs. 57.1%, P = 0.002), including in small (≤ 2 cm in diameter; 68.8% vs. 18.8%, P = 0.008) and well- or moderately-differentiated (83.3% vs. 33.3%, P = 0.031) tumors. SUVmax was comparable between 68Ga-FAPI-04 and 18F-FDG (6.96 ± 5.01 vs. 5.89 ± 3.38, P &gt; 0.05), but the TBR was significantly higher in the 68Ga-FAPI-04 group compared with the 18F-FDG group (11.90 ± 8.35 vs. 3.14 ± 1.59, P &lt; 0.001). SUVmax and the TBR in 68Ga-FAPI-04 positive lesions were associated with tumour size (both P &lt; 0.05), but not the remaining clinical and pathological features (all P &gt; 0.05).Conclusions68Ga-FAPI-04 PET/CT is more sensitive than 18F-FDG PET/CT in detecting HCC lesions, and 68Ga-FAPI-04 uptake is correlated mainly with tumour size.


Author(s):  
Franziska Walter ◽  
Constanze Jell ◽  
Barbara Zollner ◽  
Claudia Andrae ◽  
Sabine Gerum ◽  
...  

Abstract Background Target volume definition of the primary tumor in esophageal cancer is usually based on computed tomography (CT) supported by endoscopy and/or endoscopic ultrasound and can be difficult given the low soft-tissue contrast of CT resulting in large interobserver variability. We evaluated the value of a dedicated planning [F18] FDG-Positron emission tomography/computer tomography (PET/CT) for harmonization of gross tumor volume (GTV) delineation and the feasibility of semiautomated structures for planning purposes in a large cohort. Methods Patients receiving a dedicated planning [F18] FDG-PET/CT (06/2011–03/2016) were included. GTV was delineated on CT and on PET/CT (GTVCT and GTVPET/CT, respectively) by three independent radiation oncologists. Interobserver variability was evaluated by comparison of mean GTV and mean tumor lengths, and via Sørensen–Dice coefficients (DSC) for spatial overlap. Semiautomated volumes were constructed based on PET/CT using fixed standardized uptake values (SUV) thresholds (SUV30, 35, and 40) or background- and metabolically corrected PERCIST-TLG and Schaefer algorithms, and compared to manually delineated volumes. Results 45 cases were evaluated. Mean GTVCT and GTVPET/CT were 59.2/58.0 ml, 65.4/64.1 ml, and 60.4/59.2 ml for observers A–C. No significant difference between CT- and PET/CT-based delineation was found comparing the mean volumes or lengths. Mean Dice coefficients on CT and PET/CT were 0.79/0.77, 0.81/0.78, and 0.8/0.78 for observer pairs AB, AC, and BC, respectively, with no significant differences. Mean GTV volumes delineated semiautomatically with SUV30/SUV35/SUV40/Schaefer’s and PERCIST-TLG threshold were 69.1/23.9/18.8/18.6 and 70.9 ml. The best concordance of a semiautomatically delineated structure with the manually delineated GTVCT/GTVPET/CT was observed for PERCIST-TLG. Conclusion We were not able to show that the integration of PET/CT for GTV delineation of the primary tumor resulted in reduced interobserver variability. The PERCIST-TLG algorithm seemed most promising compared to other thresholds for further evaluation of semiautomated delineation of esophageal cancer.


2017 ◽  
Vol 56 (03) ◽  
pp. 91-96 ◽  
Author(s):  
Shintaro Nawata ◽  
Matsuyoshi Ogawa ◽  
Yoshinobu Ishiwata ◽  
Naomi Kobayashi ◽  
Ayako Shishikura-Hino ◽  
...  

Summary Aim: The aim of this study was to evaluate the normal distribution of sodium fluoride-18 (NaF-18) and to clarify the differences in uptake according to location and the type of the bone using positron emission tomography (PET) / computed tomography (CT). Methods: We retrospectively reviewed NaF-18 PET/CT images from 30 patients with hip joint disorders. PET/CT scans were performed 40 min after injection of approximately 185 MBq of NaF-18. To evaluate the relationship between the distribution of NaF-18 uptake and bone density, we compared the maximum standardised uptake values (SUVmax) on PET and the Hounsfield Units (HUs) on CT of the lumbar vertebra, ilium, and proximal and distal femurs. Regions of interests were defined both outside and inside the cortical bone to measure whole bone and cancellous bone only, respectively. Results: The distribution of NaF-18 differed according to the skeletal site. The lumbar vertebra showed the highest SUVmax for both whole bone and cancellous bone, followed by the ilium, proximal femur, and distal femur. The bones differed significantly in SUVmax. The distal femur showed the highest HU, followed by the proximal femur, ilium, and vertebra. Profile curve analyses demonstrated that the cancellous bones showed higher SUVmax and lower HU than the cortical bones. Conclusions: Our results demonstrate the difference in NaF-18 uptake between cancellous and cortical bones, which may explain differences in uptake by location. NaF-18 uptake does not appear to be strongly correlated with bone density, but rather with bone turnover and blood flow.


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