Image 1-The first standard of care for stones: open surgery
Another important milestone in the development of stone surgery was the development of coagulum pyelolithotomy, which consists of the injection of cryoprecipitate in renal calix1 (Image 2). This intraoperative injection of coagulation factors lead to the formation of a gelled substance (coagulum) which could encase the free-lying stones in the collecting system. By doing so, a seemingly easy to access stone at the beginning of surgery, that moved into the depths of the renal calyx, could be removed more easily. However, injecting cryoprecipitate in the renal calyx posed the risk of transmitting blood-borne diseases like hepatitis B and HIV.
Image 2-Coagulum Pyelolithotomy. Procedure overview
Stone breakage has also changed a lot over time, from the simple blind breakage of stones to electrohydraulic methods, pneumatic techniques, shock wave extracorporeal lithotripsy use, laser lithotripsy (ranging from holmium to thulium), magnetic tags and targeted microbubbles usage (Image 3).
Image 3-Evolution of stone breakage
Understanding that alkalinization of urine with the use of potassium citrate as well as sodium and potassium bicarbonate can lead to less stone precipitation, as well as dissolve stones of certain chemical composition was another important milestone (Image 4).
Image 4-Urine alkalinization in the management of kidney stone disease
Percutaneous nephrolithotomy has changed a lot with the use of flexible scopes, as they decreased the need for multiple punctures being needed (Image 5). And the change does not stop, with re-usable ureteroscopes being slowly replaced by disposable ureteroscopes. Moreover, some participants at the 39th World Congress of Endourology that went on this weekend at San Diego, CA, USA, had the chance of seeing the new MONARCH robot for endourological surgery being displayed.
Image 5-Evolution of percutaneous nephrolithotomy
Looking toward the future of kidney stone management, Dr. Stoller postulates that the key to the future lies in 3 directions:
- Understanding where stones come from. There is an “entire universe” within the papilla. We need to have a better understanding of how Randall plaques form. With that information in our pocket, we can more reliably answer patient’s questions of “What should I eat?” or “What should I drink” to avoid stone surgery or stone recurrence.
- Develop newer renal replacement therapies. We must fight for our patients and fight better ways to help patients with late-stage renal disease. Hopefully, one day soon we’ll be able to ablate the need of dialysis and address the shortage of kidney donors. On that matter, Dr. Stoller presented to the audience an artificial kidney developed at UCSF Urology.
- Lastly, urologists and must continue to constantly improve the path of minimally invasive surgery for kidney stone management.
Presented by: Marshall Stoller, MD, Professor, University of California, San Francisco
Written by: Andrei D. Cumpanas, LIFT Research Fellow, Department of Urology, University of California, Irvine. Twitter: @andreicumpanas during the 39th World Congress of Endo urology and Uro-Technology (WCET), Oct 1 - 4, 2022, San Diego, California.
References:
- Marshall S. Coagulum pyelolithotomy. Urol Clin North Am. 1983 Nov;10(4):659-64. PMID: 6636382.