Schematic illustration of the electrohydraulic lithotripsy system.
Typical form of a therapeutic SW pulse that would appear at the F2 focus.
High speed camera system used for studying the deflection of shock wave with the presence of model ankle bone.
The maximum tensile component of the SW pressure wave simulated in the x-z plane by using the FEM model. The pentagram marker in the image indicates the location of F2 focus and the solid dot represents the intended treatment point (T point) on the bone surface. The vertical distances between the shock wave geometric focus (F2) and the intended treatment points on the bone surface are (a) −12 mm, (b) −9 mm, (c) −6 mm, (d) −3 mm, (e) 0 mm, (f) 3 mm, (g) 6 mm, and (h) 9 mm.
Cavitation bubbles induced by SW's tensile components photographed using high-speed imaging technology. The vertical distances between the shock wave geometric focus (F2) and the intended treatment point on the bone surface are (a) −12 mm, (b) −9 mm, (c) −6 mm, (d) −3 mm, (e) 0 mm, (f) 3 mm, (g) 6 mm, and (h) 9 mm.
SW deflection angle quantification for both simulated and measured data. (a) A sample image illustrating how the SW deflection angle was quantified after image processing procedures done by MATLAB programs. The F2 focus of the SW source is marked as a pentagram in the figure. The central line of the outgoing acoustic beam is marked as solid line. The central trace and its extended line of the incident shock wave are marked as dashed line and dashed dotted line, respectively. (b) Comparison between the quantified SW deflection angles obtained from numerical and experimental SW propagation data.
Simulating strain energy distribution in the bone based on the FEM model. (a) A sample of calculated strain energy density distribution in the bone, as the vertical distance between SW's F2 focus and the T point on the bone surface is −6 mm. (b) Temporal evolution curves of the strain energy U integrated in the circle region around T point with a radius of 5 mm are plotted for varied vertical distances between the F2 focus and T point.
Article metrics loading...
Full text loading...