Optimization of contrast medium dosing using a body surface area-based protocol for preoperative CT...

Area of Science:

• Radiology and Imaging
• Medical Physics
• Gastroenterology

Background:

• Preoperative CT colonography-angiography (CTC-A) is crucial for colorectal cancer staging.
• Contrast enhancement variability based on patient body weight can affect image quality and diagnostic accuracy.
• Standard total body weight (TBW)-based contrast protocols may lead to inconsistent enhancement.

Purpose of the Study:

• To assess if a body surface area (BSA)-based adjusted body weight (AdBW) protocol can standardize vascular and hepatic enhancement during preoperative CTC-A.
• To compare the BSA-based AdBW protocol with the traditional TBW-based protocol in terms of enhancement consistency.

Main Methods:

• Retrospective analysis of 221 colorectal cancer patients undergoing preoperative CTC-A.
• Patients received either a TBW-based iodine protocol (600 mg I/kg) or a BSA-based AdBW protocol (21.74 g I/m²).
• Vascular and hepatic contrast enhancement, contrast-to-noise ratio (CNR), and qualitative visualization were evaluated.

Main Results:

• The AdBW protocol significantly reduced body weight dependency for vascular (aorta, SMA, IMA) and hepatic parenchymal enhancement.
• Regression slopes for enhancement parameters were substantially lower with AdBW compared to TBW.
• Vascular attenuation remained stable across all body weight groups with AdBW, and hepatic enhancement was consistent.

Conclusions:

• BSA-based AdBW dosing effectively minimizes body habitus-related variability in vascular and hepatic enhancement during preoperative CTC-A.
• This protocol offers more consistent imaging for colorectal cancer patients, potentially improving diagnostic confidence.