Intravenous contrast medium impairs CT-based muscle quality but not quantity assessment: a translational study

Area of Science:

• Radiology
• Medical Imaging
• Body Composition Analysis

Background:

• Computed Tomography (CT)-based body composition analysis (BCA) provides critical imaging biomarkers for muscle volume and quality.
• Clinical application of CT-BCA is hindered by concerns regarding the comparability of non-contrast and contrast-enhanced scans.
• Understanding the impact of contrast media (CM) on BCA is crucial for consistent clinical interpretation.

Purpose of the Study:

• To evaluate the influence of various contrast phases on volumetric CT-based body composition analysis.
• To assess the comparability of body composition metrics derived from non-contrast and contrast-enhanced CT scans.

Main Methods:

• 20 Göttingen minipigs underwent non-contrast (NC) and five contrast-enhanced CT scans at different phases.
• 114 tri-phasic human CT scans were analyzed for validation.
• A volumetric BCA network (BOA) extracted muscle radiodensity and volumes of muscle, subcutaneous adipose tissue (SAT), intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), and total adipose tissue (TAT).

Main Results:

• Contrast administration tended to reduce IMAT volumes and significantly increased muscle radiodensity in both animal models and human validation.
• Muscle radiodensity was significantly higher following CM administration (p < 0.001 in animals, p = 0.007 in humans).
• IMAT volume showed a tendency towards reduction with CM (p = 0.10 in humans), while muscle and extramuscular fat volumes remained robust.

Conclusions:

• Myosteatosis surrogates like muscle radiodensity and IMAT are susceptible to interference from contrast media.
• Volumetric quantification of muscle tissue and extramuscular adipose tissue (SAT, VAT, TAT) is robust across different contrast phases.
• Careful consideration of contrast effects is needed when interpreting CT-BCA, particularly for muscle quality metrics.