Milišić E et al., 2019: Extracorporeal shock wave lithotripsy effect on renal arterial resistive index changing
Milišić E, Zvizdić Z, Jonuzi A, Hiroš M, Milišić L, Mešić A, Begić E.
Clinic of Paediatric Surgery, University Clinical Centre Sarajevo, Sarajevo, Bosnia and Herzegovina.
Clinic of Anaesthesiology; University Clinical Centre Sarajevo, Sarajevo, Bosnia and Herzegovina.
Department of Cardiology, General Hospital "Prim.dr. Abdulah Nakaš", Department of Pharmacology, School of Medicine, Sarajevo School of Science and Technology; Sarajevo, Bosnia and Herzegovina.
Aim To investigate a correlation between resistive index (RI) level changes following extracorporeal shock wave lithotripsy (ESWL) in treated and non-treated kidneys depending on the ESWL treatment intensity. The study was conducted on 60 subjects, which were divided in two groups according to age and treatment protocol. Results In the group of patients younger than 55 years of age there was a significant increase in mean RI values, on the first (p=0.001) and second day after the treatment (p=0.007). In the group older than 55 years of age, the resulting increase in mean RI levels was also significant on the first (p=0.003) and second (p=0.011) day following the treatment. The RI values in the non-treated kidney on the first day after the treatment grew significantly (p=0.033). In the group older than 55, RI values in the non-treated kidney grew significantly on the first day after the treatment (p=0.044). In the group who received 2000 SWs, RI levels grew significantly (p=0.044) as well as in the group who received 4000 SWs during the treatment, where the significance was more pronounced (p=0.007). Conclusion There is a correlation between RI changes and the degree and localization of changes in vascular elements of the kidney. Post-ESWL treatment changes are existent and reversible, over a period of one week after the treatment.
Med Glas (Zenica). 2019 Feb 1;16(1):22-27. doi: 10.17392/975-19. FREE ARTICLE
There are several previous reports in the literature that have shown increased levels of resistive index (RI) as a consequence of shockwave effects on the renal tissue. RI is an estimate obtained from measurements with Doppler ultrasound: (Peak systolic Doppler shift waveform - Peak diastolic Doppler shift wave form) / Peak systolic Doppler shift wave form.
In this study it was demonstrated that RI increased significantly not only in the treated kidney, but also in the contra-lateral kidney. The increments were numerically small and the RI was normalized at the measurement 7 days after SWL.
One notable observation was that the increment in RI was more pronounced after 4000 shockwaves than after 2000 shockwaves. This result supports the recommendation of avoiding overtreatment with SWL during one session.
Despite the transient effect on RI it would be interesting to learn about the effect of shockwaves on RI after early repeated SWL as one way to better decide on the minimally allowed interval between two SWL sessions.