Assessment of Cirrhotic Liver Enhancement With Multiphasic Computed Tomography Using a Faster Injection Rate, Late...

Area of Science:

• Radiology
• Medical Imaging
• Diagnostic Procedures

Background:

• Liver computed tomography (CT) protocols require optimization for accurate diagnostic imaging.
• Published guidelines recommend specific adjustments to enhance image quality and diagnostic yield.

Purpose of the Study:

• To update the liver CT protocol based on current guidelines.
• To quantitatively assess the impact of protocol modifications on liver enhancement and image quality.

Main Methods:

• A modified liver CT protocol was implemented, featuring a faster contrast injection rate (5 mL/s), a delayed arterial phase (20-second trigger), and weight-based contrast dosing (1.7 mL/kg).
• Attenuation values and iodine concentrations were measured in patients with cirrhosis using both the old and modified protocols.
• Adequacy criteria included liver enhancement >50 HU in the portal venous phase or minimum iodine concentration of 500 mg I/kg.

Main Results:

• The modified protocol resulted in significantly higher aortic and portal vein attenuations during the arterial phase.
• Hepatic enhancement in the portal venous phase (61 ± 15 HU vs 51 ± 16 HU) and iodine concentrations (595 ± 88 mg I/kg vs 456 ± 112 mg I/kg) were significantly improved.
• The rate of suboptimal studies decreased from 57% to 23% with the modified protocol.

Conclusions:

• The updated liver CT protocol, incorporating a later arterial phase, faster injection, and weight-based contrast dosing, significantly enhances liver enhancement and iodine concentration.
• These protocol modifications lead to a substantial reduction in suboptimal studies for patients with cirrhosis undergoing CT scans.