Extra-corporal Shockwave Lithotripsy - for Urolithiasis

1. Extra-corporal Shockwave Lithotripsy- for Urolithiasis Dr. Chan Shu Yin Eddie Urology Division, Department of Surgery PYNEH

2. Agenda • History and basic principle of ESWL • Challenges and Complications of ESWL • Take home messages

3. ESWLEasy, simple, thing thatnothing need to learn REALLY???

5. History of ESWL • 1951 SW for treatment of brain tumours • 1971 in-vitro disintegration of kidney stones • 1974 in-vivo trials • 10/1983 1st ESWL machine HM3 installed • 1984 FDA approval • 1991 1st ESWL machine in HA hospital

6. Components of ESWL Machine • Generator & focusing system • Electrohydraulic • Electromagnetic • Piezoelectric • Coupling mechanism • Water Bath • Semi-water Bath • Water Cushion • Localization system • Fluoroscopy vs. Ultra-sonography

7. HM3 machine

8. The New Generation ESWL Machine • Principles of shockwave generation • Focusing system • Coupling • Localization • Aim as low cost, pain-free application, multifunctional use and easy handling

9. Lithostar

10. “The cellular phone… was introduced in 1984, the same year as the Dornier HM3 lithotriptor, an equally revolutionary device from a medical technology perspective. Cellular phone initially weighted in excess of 2 pounds…weigh as little as 2 ounces today. The last 15 years of lithotriptor technology have been a disappointment.” Dr. J. Lingeman

11. ESWL – Challenges • When to use ESWL? • Management of post-ESWL complications

12. Case 1 • Good case for ESWL? BMI = 49

13. Ureteric Stone • Rate of spontaneous passage • ESWL is unnecessary for small uncomplicated ureteric stones

14. Case 2

15. ESWL vs. Observation: Outcome for small asymptomatic calyceal stone <15mm • 228 patients • 200 available for FU, mean 2.2 yr (1-5 yr) • SWL 28% stone-free 15% additional Rx • OBS 17% stone-free 21% additional Rx p = 0.06p=0.27 • No difference in outcome Bristol Urological Institutes, BJU 2001;87,1-8

16. ESWL - Complications • Complications of anaesthesia or sedation / antibiotics • 1% clinical significant haematoma • 5-25% pain due to stone fragments passage • 2-6% stone obstruction – steinstrasse • Hypertension – unknown long-term effects

17. Perinephric Haematoma

18. Perinephric Haematoma • Occurrence • Radiologically 20-25% • Clinical significant - < 1% • Risk factors • HT • Uncontrolled coagulopathy • NSAID • Obesity • UTI • Bilateral treatment • Lithotriptor model – larger peak pressure and smaller focal zone

19. Case 3

20. 50 years old lady Small lower pole renal stone presented with mild loin discomfort ESWL was offered Case 4

21. 50 years old lady Small lower pole renal stone presented with mild loin discomfort ESWL was offered Developed high fever with septic shock after ESWL Need ICU care

22. 50 years old lady • Small lower pole renal stone presented with mild loin discomfort • ESWL was offered • Developed high fever with septic shock after ESWL • Need ICU care • Treated with PCN insertion and antibiotics

23. Take Home messages • Stone management can be difficult. ESWL should not be considered as a treatment modality in isolation and must not be abused. • Complications of ESWL are not very common but may lead to major morbidity. • Complications can be silent and delayed in picking up