Detection and Characterization of Renal Stones by Using Photon-Counting-based CT

Area of Science:

• Medical Imaging
• Radiology
• Urology

Background:

• Renal stones (kidney stones) pose a significant health burden, necessitating accurate detection and characterization.
• Dual-energy CT (DECT) is a current standard for renal stone analysis.
• Advancements in CT technology, such as photon-counting-detector (PCD) CT, offer potential improvements in imaging performance.

Purpose of the Study:

• To compare the diagnostic performance of a research photon-counting-detector (PCD) CT scanner against a dual-source, dual-energy CT (DECT) scanner.
• To evaluate the efficacy of both CT modalities in the detection and characterization of renal stones in human participants.

Main Methods:

• Thirty participants with known renal stones underwent both DECT and PCD CT scans at equivalent radiation doses.
• Two radiologists independently detected stones, and stone composition (uric acid vs. non-uric acid) was determined.
• Stone size and contrast-to-noise ratio were calculated, with statistical analysis including McNemar odds ratios and Cohen's kappa.

Main Results:

• A total of 160 renal stones were detected across all participants.
• PCD CT showed similar stone detection rates compared to DECT.
• Stone characterization was significantly more successful with PCD CT, particularly for small stones (≤3 mm), with a P-value of .002.

Conclusions:

• Photon-counting-detector CT exhibits comparable performance to dual-energy CT for renal stone detection.
• PCD CT offers superior capabilities for the characterization of small renal stones, enhancing diagnostic precision.
• This suggests PCD CT as a promising technology for improved renal stone assessment.