Detection of Myocardial Metabolic Abnormalities by 18F-FDG PET/CT and Corresponding Pathological Changes in Beagles with Local Heart Irradiation.
10.3348/kjr.2015.16.4.919
- Author:
Rui YAN
1
;
Jianbo SONG
;
Zhifang WU
;
Min GUO
;
Jianzhong LIU
;
Jianguo LI
;
Xinzhong HAO
;
Sijin LI
Author Information
1. Nursing College of Shanxi Medical University, Taiyuan 030001, China.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
18F-FDG PET/CT;
Radiation-induced heart disease;
Radiotherapy;
Pathology
- MeSH:
Animals;
Dogs;
Fasting;
Fluorodeoxyglucose F18/*metabolism;
Heart/*radiography;
Heart Injuries/*radiography;
Male;
Myocardium/metabolism/pathology;
Positron-Emission Tomography/*methods;
Radiation Injuries/diagnosis/*radiography;
Thoracic Neoplasms/radiotherapy;
Tomography, X-Ray Computed/*methods
- From:Korean Journal of Radiology
2015;16(4):919-928
- CountryRepublic of Korea
- Language:English
-
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.