PHTY207 Lecture Notes - Lecture 23: Therapeutic Ultrasound, Piezoelectricity, Cavitation
Document Summary
Imaging -> real time us, pregnancy, msk: dental drills/descalers, detecting cracks in metal/bone -> stress #s, cleaning jewellery. Detail the biological basis for ultrasound: biological basis 1. Stimulates cell activity and changes cell membrane permeability. Increase exchanges across capillary walls and cell membranes (stable cavitation & acoustic streaming: accelerate inflammatory phase and stimulate collagen production during proliferation phase. Increase blood flow (heat: wouldn"t want this in first 72 hours. Increase soft tissue extensibility (heat: e. g. scars and adhesions. Increase flexibility (as an adjunct to stm, exs: hasten resolution of inflammation, pain relief, reduce muscle spasm (+/- wound healing) Standing wave formation: waves in opposite directions, ensure continuous movement of the sound head, periosteal pain, avoid superficial bone, move the sound head more quickly, decrease the intensity (w/cm2) Infective disorders (cid:894)spread; activity(cid:895: circulatory insufficiency (varicose veins; dvts, metal implants (tkr, thr, haemorrhagic conditions, treatment over an inbuilt stimulator (e. g. cardiac pacemaker, tumours, tuberculosis, osteomyelitis, neural tissue - superficial or exposed.
