Gd-DTPA as a contrast agent in CT

Area of Science:

• Radiology
• Medical Imaging
• Contrast Agents

Background:

• Gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) is a widely used contrast agent in magnetic resonance (MR) imaging.
• The potential impact of residual contrast agents on subsequent imaging modalities, such as computed tomographic (CT) scans, requires evaluation.

Purpose of the Study:

• To assess the effect of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) on computed tomographic (CT) imaging performed after MR imaging.
• To determine the visibility and attenuation characteristics of Gd-DTPA in CT scans following MR contrast administration.

Main Methods:

• Evaluation of CT scans of two Gd-DTPA solutions to assess attenuation.
• Analysis of CT images from two patients who underwent CT after Gd-DTPA-enhanced MR imaging.

Main Results:

• Gd-DTPA solutions demonstrated substantial attenuation on CT scans.
• High attenuation of concentrated Gd-DTPA was observed in the urinary bladder and renal collecting system in patients.
• Gd-DTPA at concentrations used for MR imaging resulted in only minor enhancement of the renal cortex on CT.

Conclusions:

• Gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) exhibits significant attenuation on computed tomographic (CT) scans.
• Concentrated Gd-DTPA is detectable in the urinary tract on CT after MR imaging.
• The enhancement effect of Gd-DTPA on the renal cortex during CT after MR imaging is minimal at current clinical concentrations.