Postoperative Imaging Patterns of Pediatric Nephrolithiasis: Opportunities for Improvement.

Purpose: Imaging following surgical intervention for nephrolithiasis is important to define operative success and ensure the absence of silent obstruction. We assessed nationwide postoperative imaging patterns in children undergoing ureteroscopy and shock wave lithotripsy.
Materials and Methods: We reviewed the MarketScan® Commercial Claims and Encounters database from 2007 to 2013 for patients 1 to 18 years old undergoing ureteroscopy or shock wave lithotripsy. We assessed imaging exposure following index procedure within 90 days as a primary analysis and 180 days as a secondary analysis of the index procedure. Univariate and multivariate statistical analyses were performed to assess factors associated with undergoing postoperative imaging.
Results: A total of 4,251 children met inclusion criteria, of whom 1,647 had undergone shock wave lithotripsy and 2,604 had undergone ureteroscopy. Postoperative imaging was performed in 57.5% of the cohort, with a higher proportion of children undergong imaging following shock wave lithotripsy compared to ureteroscopy (73% vs 47.8%, p <0.001). Noncomputerized tomographic imaging modalities were most common following ureteroscopy (70.8%) and shock wave lithotripsy (84.6%). Younger children and those with complex medical conditions or complicated postoperative courses were more likely to undergo followup imaging. Computerized tomography was more commonly used in older children and females. At 180-day followup 63% of the cohort had undergone any imaging, again more frequently following shock wave lithotripsy (77.0%) vs ureteroscopy (45.0%).
Conclusions: A large percentage of children with nephrolithiasis do not undergo followup imaging after shock wave lithotripsy, and even fewer undergo imaging after ureteroscopy. Most followup imaging is done within 90 days of surgery. Further work is needed to define appropriate postoperative imaging practices in this population.