📃 Paper Title: Lower pole I: a prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis-initial results
🧍 Author: D M Albala
🕒 Year: 2001
📚 Journal: The Journal of Urology
🌎 Country: USA
ㅤContext to the study:
Can you tell me about a trial comparing percutaneous nephrolithotomy (PCNL) than with shock wave lithotripsy (SWL) techniques for then management of lower renal pole stones?
ㅤ✅ Take-home message of study:
For management of lower pole kidney stones ≤30mm:
Overall, stone free clearance rate was higher with percutaneous nephrolithotomy (PCNL) than with shock wave lithotripsy (SWL) (95% vs 37%).
However, SWL had an acceptable stone free rate (63%) for stones ≤10mm, and is therefore recommended for stones in this size bracket due to an anticipated lower morbidity.
The authors conclude that stones greater than 10mm should preferably be managed with PCNL, given the much higher stone free clearance rate.
ㅤ Randomised control trial
ㅤ
Study participants:
Number included: 128
Patients greater than 18 years old
Symptomatic lower pole calculi 3cm or less
Mean stone size 14.43mm
Stone size similar overall between groups
ㅤ
ㅤ
Key study outcomes:
Stone-free clearance rate, independent of stone size, was higher with PCNL versus SWL (95% vs 37%, p<0.001)
Efficacy of SWL (stone clearance) greater when treating smaller stones compared to larger ones ((9.9 versus 14.8mm, p =0.003)
Lower re-treatment rate in those treated with PCNL compared to SWL (9% vs 16%)
Shorter hospital stay with SWL (0.55 days vs 2.66 days, p<0.001)*
Overall complication/morbidity rate was higher with PCNL (22%) versus SWL (11%), but this did not reach statistical significance (p=0.087). Serious complications were observed in 3 patients (a perinephric haematoma following SWL and bleeding requiring transfusion and AV fistula requiring embolization, following PCNL)
Differences in intrarenal anatomy (available for 38 patients) did not appear to influence stone clearance rates for SWL
No significant difference in quality of life outcomes between both procedures and stone-free status
*duration of stay shortened over time for PCNL
ㅤ
ㅤ
Study Limitations:
Sponsorship bias- significant manufacturer funding
Operator and lithotripter variation: difference in quality of treatment/likelihood of morbidity
12% lost to follow up
Selection bias: exclusion of patients with unfavorable factors for lithotripsy to improve lithotripsy rates
Although taking overall stone size was not significantly different between patients treated with lithotripsy versus PCNL, lithotripsy group had more patients with 21-30mm stones than PCNL (11% of patients vs 9% in PCNL, p=0.03). This could have contributed to lithotripsy's lower overall stone free clearance rate.
ㅤ