Strategies to optimize shock wave lithotripsy outcome: Patient selection and treatment parameters

Table 1 Stone criteria for shock wave lithotripsy

Sub-optimal features suggesting alternate therapy

Stone size > 2 cm

Multiple stones

Lower pole stone

Hounsfield unit > 1000

History of cystine, calcium oxalate monohydrate, matrix stones

Table 2 Patient criteria for shock wave lithotripsy

Sub-optimal features suggesting alternate therapy
Obesity - skin to stone distance > 10 cm
Pelvic kidney
Horseshoe kidney
Calyceal diverticulum

Table 3 Absolute contraindications to shock wave lithotripsy

Anticoagulation

Bleeding diathesis

Pregnancy

Severe skeletal malformations

Distal obstruction

Infection associated with obstruction

Table 4 Technical factors that optimize shock wave lithotripsy outcome

General anesthesia

Optimal coupling

Low shock wave rate (60 shocks per minute)

Wider focal zone

Active intraoperative monitoring