Mr. Shady NafieUrology Clinical Research

Fellow

Dr. Jonathan MillsFY1 in Urology

Dr. Jaitender MinhasFY1 in Urology

Mr. Masood A KhanUrology Consultant

Mobile Lithotripsy ServiceThe Efficacy

of

A one-year review of 222 patients

Mr. James E DyerUrology Clinical Research

Fellow

•Introduced in February 1980•Approved by FDA in 1984•Dramatically changed the

management of urinary tract stones

Extra-corporeal Shock Wave LithotripsyESWL

EAU GuidelinesESWL can remove > 90% of stones in adults

Stone Size ≤20 mm >20 mm

Stone Clearance Rates

66-99% 45-63%

Stone Clearance Rates (Dornier HM3 Lithotripter)

75-89% 39-63%

Success rate depends on:

Lithotripter

Patient Operator

Stone

• Efficacy

• Size• Site• Density

• Habitus (BMI)

• Efficiency

LGH Performance

•Storz MODULITH® SLK Lithotripter.•Dual localisation (Ultrasound, X-ray

mobile image intensifier).•Technicians.•Middle grade doctor.

July 2011 - July 2012

LGH Performance•Site.•Size.•Opacity

.•Density

.

•Number.•Shocks.•Energy.

Stones Sessions Stents

•Yes/No

• ≤2 mm residual stone, was considered stone clear.• Statistical analysis: Fisher’s exact test.

LGH Performance•222 cases.•Mean Age: 51 yrs. (18-90).•Male : Female = 2.4 :1

LGH PerformanceMean values:•Size: 15 mm (4-24)•Density: 811 HU (181-1711).•Shocks: 3185 (1550 - 4000).•Energy: 17.3 KV (9.8 - 20).

LGH PerformanceNumber of ESWL sessions

LGH PerformanceTotal Stone Clearance* Rate

*≤2 mm residual stone, was considered stone clear.

LGH PerformanceStone Clearance Yes No P-Value

Number of Patients 110 112 N/A

Mean HU 747 854 <0.05

Mean Shocks 3252 3155 <0.05

Mean Energy 17 17 0.732

LGH PerformanceStone Size

61%

55%

18%

13%

50%

P < 0.01

LGH Performance

P = 0.577

Site Number Cleared PercentageUpper Pole 15 8 53%Middle Pole 32 19 59%Lower Pole 75 37 49%

Kidney Pelvis 51 21 41%Upper Ureter 32 15 47%Middle Ureter 10 7 70%Lower Ureter 7 4 57%

Stone Site

LGH Performance

46%

Stent vs No Stent (Ureteric stones)

52% P = 0.394

LGH Performance

49%

Stone Opacity

52% P = 0.829

LGH Performance

55%

33% P < 0.01

Stone Density (HU)

LGH Performance

53%

Sex

42% P = 0.141

ConclusionThe performance of our mobile ESWL

service is significantly poorer than that expected.

49.5%

66-99%vs.

Factors affected Stone Clearance Rate

Lithotripter

Patient Operator

Stone

?? Efficacy

✔ Size✔ DensityX OpacityX Site.X Stent

X Sex?? Habitus (BMI)

✔ No. of shockwaves?? Energy level?? Efficiency

Conclusion

Maintenance?

Technician?

Lack of Ownership?

Mobile ESWL

Questions

Dr. Jonathan Mills

FY1 in Urology

Dr. Jaitender MinhasFY1 in Urology

Mr. Masood A Khan

Urology Consultant

Mr. Shady NafieUrology Research

Fellow

Mr. James E DyerUrology Research

Fellow