Motion artifacts in kidney stone imaging using single-source and dual-source dual-energy CT scanners: a phantom study

Area of Science:

• Medical Imaging
• Radiology
• Nephrology

Background:

• Dual-energy computed tomography (DECT) accurately differentiates uric acid from non-uric acid kidney stones.
• Dual-source (DS) scanners acquire low- and high-energy images simultaneously, while single-source (SS) scanners acquire them sequentially.
• Motion artifacts can compromise image quality and diagnostic accuracy in DECT.

Purpose of the Study:

• To evaluate the impact of motion artifacts on kidney stone classification using both SS-DECT and DS-DECT.
• To compare the accuracy of stone classification between SS-DECT and DS-DECT under induced motion conditions.

Main Methods:

• 114 kidney stones were imaged using both DS-DECT and SS-DECT (80 and 140 kVp) with and without induced motion.
• Material-specific images were generated through postprocessing.
• Dual-energy ratio (DER) and stone material were determined and compared across scan types.

Main Results:

• Without motion, SS-DECT correctly classified all stones, while DS-DECT misclassified two cystine stones.
• With induced motion, SS-DECT misclassified 94% of stones, compared to 11% with DS-DECT (P < 0.0001).
• Stone size did not influence misclassification; stone type affected misclassification more with DS-DECT (cystine).

Conclusions:

• Motion artifacts can lead to kidney stone misclassification in DECT.
• DS-DECT demonstrates superior resilience to motion artifacts compared to SS-DECT.
• Proximity of stones and potential miscounting of stones in DS-DECT are significant considerations.