Abstract
Introduction: NCCT parameters and images play an important role in determining the best surgical approach in management of urinary stone. Knowledge of chemical composition of stone is crucial in selecting optimal surgical approach and it can be of great help in reducing the stone recurrence rate.
Objective: Our study aimed at assessing the predictive value of HU and VSB in success of ESWL / URSL and to evaluate whether HU value can predict the urinary calculi composition.
Material and Methods: Our study included 55 patients of upper urinary tract calculi diagnosed on NCCT. Patients were grouped as Group A (n=29) with renal / upper ureteral calculi subjected to ESWL and Group B (n=26) with stone in mid / lower ureter subjected to URSL.
Observations: A statistically significant association of VSB was found with the no. of sessions required to achieve SFS following ESWL (p value < 0.01) in Group A patients. In Group B patients, single session stone free rate following URSL was 96.15%. HU value was not an independent predictor of SFS in either of the group. However VSB and HU value had an impact on total duration of procedure and energy settings required for fragmentation during URSL. The correlation between HU value and chemical composition of calculi could not be clearly depicted as none of the calculi was of pure nature.
Conclusion: VSB was an independent predictor influencing the outcome of ESWL. HU value was not independent predictor of successful outcome of ESWL / URSL in our study.
Keywords/Abbreviations: ESWL–Extracorporeal Shock Wave Lithotripsy, URSL–Ureteroscopic Lithotripsy, SFS–Stone Free Status, VSB–Volumetric Stone Burden, HU–Hounsfield Unit.
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DOI: https://dx.doi.org/10.18535/jmscr/v5i5.124
