Bulbul E. et al., 2021: Ureteral wall thickness is an independent parameter affecting the success of extracorporeal shock wave lithotripsy treatment in ureteral stones above the iliac crest.
Bulbul E, Ilki FY, Gultekin MH, Erozenci A, Tutar O, Citgez S, Tansu N, Onal B.
Department of Urology, Istanbul University-Cerrahpasa, Cerrahpasa School of Medicine, Istanbul, Turkey.
Department of Radiology, Istanbul University-Cerrahpasa, Cerrahpasa School of Medicine, Istanbul, Turkey.
Abstract
Background: To investigate the relationship between ureteral wall thickness (UWT) and other variables of patients who underwent extracorporeal shock wave lithotripsy (SWL) in the primary treatment of the ureteral stone above the iliac crest level.
Material and methods: A total of 147 patients aged 18 years and older, who underwent SWL in our clinic between December 2016 and December 2019 for the treatment of ureteral stones above the iliac crest level and had non-contrast enhanced abdominal computed tomography scans before the procedure were included in the clinical study. The results were evaluated at 3 months after SWL. The absence of residual fragments was considered as stone-free status, and the existence of any size residual fragment was considered as treatment failure.
Results: In our study, the mean age of the patients was 42.4 ± 12.8 years, and the stone-free rate was 92.5%. The median transverse stone size was 7.5 mm (min 2.8-max 15), and the median UWT was 4.2 mm (1-8.7). In the multivariate analysis, UWT (P = .002) and multiple stone presence (P = .027) were found to be independent factors affecting stone-free status. In the receiver operating characteristic curve analysis, the optimal threshold value for UWT was determined as 5.25 mm.
Conclusions: We found that UWT was the most important independent variable associated with increased failure in SWL treatment. The presence of multiple stones was another independent factor that increased the failure rates. Using SWL technology through experience accumulated with the mechanical hardware of the machine, we can select patients who are more suitable for this treatment and improve treatment outcomes.
Int J Clin Pract. 2021 Apr 23:e14264. doi: 10.1111/ijcp.14264. Online ahead of print. PMID: 33891784
Comments 1
A well-written paper.
How was the study done? All ureteral stones above the iliac crest level between December 2016 and December 2019 were included. “ESWL was applied to all radiopaque ureteral stones above the iliac crest, regardless of patient selection… if they had ureteral stone which was not passed in 4 weeks. Patients with stone size more than 15 mm, secondary treatment, were excluded from the study. SWL was performed by a single urologist with 30 years of SWL experience.”
“Treatment was terminated when complete fragmentation of the stone was noted on fluoroscopy. If there was persistent or incomplete fragmentation of the stone(s) noted on fluoroscopy after the maximum number of shocks had been delivered, a repeat SWL session was performed at 5-7 days after the previous one. When appropriate fragmentation was seen in each session, the procedure was scheduled for next sessions. SWL was regarded as a failure if no fragmentation was noted after the third session. However, if there was adequate fragmentation and no complications, SWL was continued for seven sessions. The results were defined as stone-free status and treatment failure according to the NCCT evaluation undertaken at 3 months after SWL.”
“Using the NCCT images taken before each SWL session of each stone, all parameters were measured by a single radiologist (OT) with 15 years of experience in abdominal radiology, who was blinded to the treatment results of the patients.”
The overall success rate was 92,5% (136/147) and “the treatment was successful in all 124 patients (100%) with a UWT of