(UroToday.com) On the fourth day of the WCET 2024 Annual Meeting in Seoul, South Korea, the twenty-fifth moderated poster session included the work of Mr. D. Daniel Baldwin of Loma Linda Urology. Here, he presented work regarding a comparison of volumetric stone measurement methods.
A recurrent theme throughout the conference has included that of volumetric stone measurements. Indeed, as calculi are three-dimensional in nature, there is a movement towards standardizing these measurements, as they remain imperative for ensuring optimal patient treatment and outcomes. Moreover, current guidelines are based upon one-dimensional measurements of nephrolithiasis. For Mr. Baldwin and colleagues, they sought to explore accuracy, precision, and convenience of volumetric measurements by comparing three approaches: Enterprise Imaging, 3D Slicer, and the scalene ellipsoid formula.
To accomplish this, they utilized a silicone kidney with five phantom Bego stones, with a ratio of 15:3 BegoStone Plus to water, mimicking calcium oxalate stones. Such samples ranged in size from 1.11 cm3 to 51.5 cm3. The phantom kidneys were then loaded with Aquasonic 100 water-based jelly. Stones were placed into the upper calyx and a GE Discovery CT750 HD 64 slice scanner was utilized. After uploading the DICOM file, various staff (medical students, residents, fellow, and a researcher) measures the volume of each stone for the respective methods.
Overall, Mr. Baldwin et al. discovered that Enterprise imaging was associated with a significantly lower mean relative error as compared to 3D slicer and the ellipsoid formula, as well as high ease of use (Figure 1).
Figure 1. Results for mean relative error and ease of use.
Inter-observer reliability was high for all modalities, assessed via an interclass correlation coefficient, while precision was evaluated using standard deviation (Table 1). From these findings, Enterprise imaging proved to be more accurate and precise. Furthermore, the application may potentially improve clinical outcomes with regard to stone passage, stone-free rates, and operative time. In sum, such a method may standardize urological practice and could be employed to impact management strategies.
Table 1. The mean relative error, coefficient of determination, and interclass correlational coefficient of the volume measurement methods.
Mr. Baldwin’s presentation subsequently sparked a perceptive discussion between moderators and guests, reviewing the importance of volumetric integration into radiologic software. A member of the audience then approached to inquire about the involvement with radiology about the difficulty level of producing an automatic volume in their platform. “To my knowledge, we have not had discussions with radiology. However, [at Loma Linda] Enterprise Imaging is built into our electronic medical record system, which streamlines in-house measurement.” A moderator then responded, “This is a case where if this were to become automated, an algorithm could segment and measure kidney stones that are included into the radiologic impression, sparing the radiologist of manual measuring.”
Dr. Ilya Sobol, among audience members, inquired about the duration of each method. “We do have time measurements. Enterprise Imaging and scalene ellipsoid formula took about 20 seconds, while 3D slicer was about 4.5 minutes”.
In conclusion, Mr. Baldwin's study highlights the advantages of Enterprise Imaging over other methods for volumetric stone measurements, offering superior accuracy and efficiency. The findings suggest that integrating such methods into clinical practice could standardize measurements and enhance patient outcomes.
Presented by: D. Daniel Baldwin, Loma Linda University Medical Center, Loma Linda, California
Written by: Mariah Hernandez, Research Specialist, Department of Urology, University of California Irvine, @mariahch00 on Twitter during the 2024 World Congress of Endourology and Uro-Technology: August 12 -16, 2024, Seoul, South Korea