Shock Wave Therapies
Acoustic shock waves use high amplitude acoustic pulses (normally in the range of 10 to 100 MPa) with durations on the order of 1 microsecond. They can induce therapeutic effects in tissue by mechanical means: either through direct stress/strain or by acoustic cavitation. The main use of shock waves in medicine has been lithotripsy in which shock waves are used to fragment kidney stones so that they can be passed naturally. However, shock waves have also been considered for other applications such as treatment of soft-tissue pain (e.g. tendonitis and heel spurs), promoting repair or growth of bone, neo-vascularisation and wound healing. The efficacy of these other applications is not always clear and the mechanisms are poorly understood.
Areas of research carried out in BUBBL include:
- Understanding shock wave interaction with elastic objects, in particular kidney stones and bone. This image is a snapshot showing the stress field created in a natural kidney stone.
- Interaction of shock waves with soft tissue and how shock waves may damage tissue. This image is a B-mode ultrasound image of a pig kidney immediately after being subject to a shock wave - the circled region is cavitation created by the shock wave in the collecting system.
- Tracking of kidney stones during lithotripsy.
- How shock waves may promote repair of bone fracture.
This image shows a fractured rat femur that has been subject to shock waves. The circled region shows the initial formation of new bone.