Limits...
Detection of Myocardial Metabolic Abnormalities by 18F-FDG PET/CT and Corresponding Pathological Changes in Beagles with Local Heart Irradiation.

Yan R, Song J, Wu Z, Guo M, Liu J, Li J, Hao X, Li S - Korean J Radiol (2015)

Bottom Line: High FDG uptake in irradiation field was detected in 33.3% (4/12) of 12H-F protocol and 83.3% (10/12) of F-HFD protocol in visual analysis, respectively (p = 0.031).The pathology of the irradiated myocardium showed obvious perivascular fibrosis and changes in mitochondrial vacuoles.An F-HFD preparation protocol used before obtaining PET/CT can improve the sensitivity of the detection of cardiotoxicity associated with radiotherapy.

View Article: PubMed Central - PubMed

Affiliation: Nursing College of Shanxi Medical University, Taiyuan 030001, China. ; Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan 030001, China.

ABSTRACT

Objective: To determine the efficacy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in the detection of radiation-induced myocardial damage in beagles by comparing two pre-scan preparation protocols as well as to determine the correlation between abnormal myocardial FDG uptake and pathological findings.

Materials and methods: The anterior myocardium of 12 beagles received radiotherapy locally with a single X-ray dose of 20 Gy. 18F-FDG cardiac PET/CT was performed at baseline and 3 months after radiation. Twelve beagles underwent two protocols before PET/CT: 12 hours of fasting (12H-F), 12H-F followed by a high-fat diet (F-HFD). Regions of interest were drawn on the irradiation and the non-irradiation fields to obtain their maximal standardized uptake values (SUVmax). Then the ratio of the SUV of the irradiation to the non-irradiation fields (INR) was computed. Histopathological changes were identified by light and electron microscopy.

Results: Using the 12H-F protocol, the average INRs were 1.18 ± 0.10 and 1.41 ± 0.18 before and after irradiation, respectively (p = 0.021). Using the F-HFD protocol, the average INRs were 0.99 ± 0.15 and 2.54 ± 0.43, respectively (p < 0.001). High FDG uptake in irradiation field was detected in 33.3% (4/12) of 12H-F protocol and 83.3% (10/12) of F-HFD protocol in visual analysis, respectively (p = 0.031). The pathology of the irradiated myocardium showed obvious perivascular fibrosis and changes in mitochondrial vacuoles.

Conclusion: High FDG uptake in an irradiated field may be related with radiation-induced myocardial damage resulting from microvascular damage and mitochondrial injury. An F-HFD preparation protocol used before obtaining PET/CT can improve the sensitivity of the detection of cardiotoxicity associated with radiotherapy.

No MeSH data available.


Related in: MedlinePlus

18F-FDG cardiac PET/CT images before RT from beagles treated with two pre-scan preparations.Grade 0 image from M4 using F-HFD protocol shows homogeneously minimal myocardial FDG uptake; Grade 1 image from M3 using F-HFD protocol shows mostly minimal or mild myocardial FDG uptake; Grade 2 image from M10 using 12H-F protocol shows mostly intense or moderate myocardial FDG uptake; Grade 3 image from M2 using 12H-F protocol shows homogeneously intense myocardial FDG uptake. 12H-F = 12 hours of fasting, 18F-FDG = 18F-fluorodeoxyglucose, F-HFD = fasting followed by a high-fat diet, PET/CT = positron emission tomography/computed tomography, RT = radiotherapy
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4499559&req=5

Figure 2: 18F-FDG cardiac PET/CT images before RT from beagles treated with two pre-scan preparations.Grade 0 image from M4 using F-HFD protocol shows homogeneously minimal myocardial FDG uptake; Grade 1 image from M3 using F-HFD protocol shows mostly minimal or mild myocardial FDG uptake; Grade 2 image from M10 using 12H-F protocol shows mostly intense or moderate myocardial FDG uptake; Grade 3 image from M2 using 12H-F protocol shows homogeneously intense myocardial FDG uptake. 12H-F = 12 hours of fasting, 18F-FDG = 18F-fluorodeoxyglucose, F-HFD = fasting followed by a high-fat diet, PET/CT = positron emission tomography/computed tomography, RT = radiotherapy

Mentions: Before RT, inhibition of physiological myocardial 18F-FDG uptake by two prescan protocols was judged by two experienced observers visually and also quantitatively by measuring the maximal standardized uptake value (SUVmax) of the left ventricular myocardium. For the qualitative visual estimation of 18F-FDG myocardial uptake, 18F-FDG PET/CT scans were divided into four grades as referenced by Williams and Kolodny (14): 0, homogeneously minimal; 1, mostly minimal or mild uptake; 2, mostly intense or moderate uptake; and 3, homogeneously intense (Fig. 2). Grade 0 can be recognized as complete inhibition of physiological myocardial uptake.


Detection of Myocardial Metabolic Abnormalities by 18F-FDG PET/CT and Corresponding Pathological Changes in Beagles with Local Heart Irradiation.

Yan R, Song J, Wu Z, Guo M, Liu J, Li J, Hao X, Li S - Korean J Radiol (2015)

18F-FDG cardiac PET/CT images before RT from beagles treated with two pre-scan preparations.Grade 0 image from M4 using F-HFD protocol shows homogeneously minimal myocardial FDG uptake; Grade 1 image from M3 using F-HFD protocol shows mostly minimal or mild myocardial FDG uptake; Grade 2 image from M10 using 12H-F protocol shows mostly intense or moderate myocardial FDG uptake; Grade 3 image from M2 using 12H-F protocol shows homogeneously intense myocardial FDG uptake. 12H-F = 12 hours of fasting, 18F-FDG = 18F-fluorodeoxyglucose, F-HFD = fasting followed by a high-fat diet, PET/CT = positron emission tomography/computed tomography, RT = radiotherapy
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4499559&req=5

Figure 2: 18F-FDG cardiac PET/CT images before RT from beagles treated with two pre-scan preparations.Grade 0 image from M4 using F-HFD protocol shows homogeneously minimal myocardial FDG uptake; Grade 1 image from M3 using F-HFD protocol shows mostly minimal or mild myocardial FDG uptake; Grade 2 image from M10 using 12H-F protocol shows mostly intense or moderate myocardial FDG uptake; Grade 3 image from M2 using 12H-F protocol shows homogeneously intense myocardial FDG uptake. 12H-F = 12 hours of fasting, 18F-FDG = 18F-fluorodeoxyglucose, F-HFD = fasting followed by a high-fat diet, PET/CT = positron emission tomography/computed tomography, RT = radiotherapy
Mentions: Before RT, inhibition of physiological myocardial 18F-FDG uptake by two prescan protocols was judged by two experienced observers visually and also quantitatively by measuring the maximal standardized uptake value (SUVmax) of the left ventricular myocardium. For the qualitative visual estimation of 18F-FDG myocardial uptake, 18F-FDG PET/CT scans were divided into four grades as referenced by Williams and Kolodny (14): 0, homogeneously minimal; 1, mostly minimal or mild uptake; 2, mostly intense or moderate uptake; and 3, homogeneously intense (Fig. 2). Grade 0 can be recognized as complete inhibition of physiological myocardial uptake.

Bottom Line: High FDG uptake in irradiation field was detected in 33.3% (4/12) of 12H-F protocol and 83.3% (10/12) of F-HFD protocol in visual analysis, respectively (p = 0.031).The pathology of the irradiated myocardium showed obvious perivascular fibrosis and changes in mitochondrial vacuoles.An F-HFD preparation protocol used before obtaining PET/CT can improve the sensitivity of the detection of cardiotoxicity associated with radiotherapy.

View Article: PubMed Central - PubMed

Affiliation: Nursing College of Shanxi Medical University, Taiyuan 030001, China. ; Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan 030001, China.

ABSTRACT

Objective: To determine the efficacy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in the detection of radiation-induced myocardial damage in beagles by comparing two pre-scan preparation protocols as well as to determine the correlation between abnormal myocardial FDG uptake and pathological findings.

Materials and methods: The anterior myocardium of 12 beagles received radiotherapy locally with a single X-ray dose of 20 Gy. 18F-FDG cardiac PET/CT was performed at baseline and 3 months after radiation. Twelve beagles underwent two protocols before PET/CT: 12 hours of fasting (12H-F), 12H-F followed by a high-fat diet (F-HFD). Regions of interest were drawn on the irradiation and the non-irradiation fields to obtain their maximal standardized uptake values (SUVmax). Then the ratio of the SUV of the irradiation to the non-irradiation fields (INR) was computed. Histopathological changes were identified by light and electron microscopy.

Results: Using the 12H-F protocol, the average INRs were 1.18 ± 0.10 and 1.41 ± 0.18 before and after irradiation, respectively (p = 0.021). Using the F-HFD protocol, the average INRs were 0.99 ± 0.15 and 2.54 ± 0.43, respectively (p < 0.001). High FDG uptake in irradiation field was detected in 33.3% (4/12) of 12H-F protocol and 83.3% (10/12) of F-HFD protocol in visual analysis, respectively (p = 0.031). The pathology of the irradiated myocardium showed obvious perivascular fibrosis and changes in mitochondrial vacuoles.

Conclusion: High FDG uptake in an irradiated field may be related with radiation-induced myocardial damage resulting from microvascular damage and mitochondrial injury. An F-HFD preparation protocol used before obtaining PET/CT can improve the sensitivity of the detection of cardiotoxicity associated with radiotherapy.

No MeSH data available.


Related in: MedlinePlus