Quantitative assessment of the atherosclerotic burden of the aorta by combined FDG-PET and CT image analysis: a new concept.
BACKGROUND
Our objective was to develop a technique for quantifying the extent of atherosclerosis in the aorta by combining standard uptake values (SUVs) in the aortic wall with volumetric data provided by computed tomography (CT).


METHODS
Eighteen patients who had both 18-fluorodeoxyglucose (FDG)-positron emission tomography (PET) and contrast-enhanced CT of the chest and abdomen were selected. All had homogeneous diffuse FDG wall uptake in four segments of the aorta. We divided the patients into three groups according to their age and measured FDG uptake in all four segments of the aorta by calculating the mean SUV for each segment. On each axial CT image, region-of-interest tracings along the inner and outer wall contours of the aorta were generated. The inner surface area was subtracted from the outer surface area. The net area values for each segment were subsequently multiplied by slice thickness to calculate arterial wall volume. By multiplying SUV with wall volume, we were able to calculate the atherosclerotic burden (AB) for each segment of the aorta. We compared the aortic wall volumes, SUVs and AB values in each arterial segment for each age group.


RESULTS
In each aortic wall segment, AB values, SUVs and wall volumes increased with age (P<.05).


CONCLUSIONS
AB can be used as an indicator of the extent of the atherosclerotic process in the aorta through the use of both metabolic and morphologic data provided by FDG-PET and CT, respectively. This may allow for the optimal screening, diagnosis and management of patients with this common and potentially lethal disorder.
Bural
Gonca G
GG
Division of Nuclear Medicine, Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
Torigian
Drew A
DA
Chamroonrat
Wichana
W
Alkhawaldeh
Khaled
K
Houseni
Mohamed
M
El-Haddad
Ghassan
G
Alavi
Abass
A
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000473:pathology; D001018:Aortic Diseases / Q000175:diagnosis*; D050197:Atherosclerosis / Q000175:diagnosis*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18