Intravenous contrast injection significantly affects bone mineral density measured on CT
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The objective is to evaluate the effect of intravenous contrast media on bone mineral density (BMD) assessment by comparing unenhanced and contrast-enhanced computed tomography (CT) examinations performed for other indications.
One hundred and fifty-two patients (99 without and 53 with malignant neoplasm) who underwent both unenhanced and two contrast-enhanced (arterial and portal venous phase) abdominal CT examinations in a single session between June 2011 and July 2013 were included. BMD was evaluated on the three examinations as CT-attenuation values in Hounsfield Units (HU) in the first lumbar vertebra (L1).
CT-attenuation values were significantly higher in both contrast-enhanced phases, compared to the unenhanced phase (p < 0.01). In patients without malignancies, mean ± standard deviation (SD) HU-values increased from 128.8 ± 48.6 HU for the unenhanced phase to 142.3 ± 47.2 HU for the arterial phase and 147.0 ± 47.4 HU for the portal phase (p < 0.01). In patients with malignancies, HU-values increased from 112.1 ± 38.1 HU to 126.2 ± 38.4 HU and 130.1 ± 37.3 HU (p < 0.02), respectively. With different thresholds to define osteoporosis, measurements in the arterial and portal phase resulted in 7-25 % false negatives.
Our study showed that intravenous contrast injection substantially affects BMD-assessment on CT and taking this into account may improve routine assessment of low BMD in nonquantitative CT.
• Routine CT may gain a role in bone attenuation measurements for osteoporosis
• Contrast media injection has substantial influence on CT-derived bone density
• Contrast-enhanced CT leads to underestimation of osteoporosis compared to unenhanced CT
• Adjusting for contrast injection phase may improve CT screening protocols for osteoporosis.
KeywordsOsteoporosis Screening Computed tomography Contrast media Bone mineral density
Abbreviations and acronyms
Body mass index
Bone mineral density
Dual-energy x-ray absorptiometry
Lumbar vertebral body 1
Quantitative computed tomography
Region of interest
The scientific guarantor of this publication is Dr. P.A. de Jong. The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article. The authors state that this work has not received any funding. No complex statistical methods were necessary for this paper. Institutional Review Board approval was not required because the Medical Research Involving Human Subjects Act (WMO) does not apply to the study. Written informed consent was waived by the Institutional Review Board. Methodology: retrospective, observational, performed at one institution.