Acoustic microstreaming results in what phenomenon in ultrasound therapy?

Acoustic microstreaming results in what phenomenon in ultrasound therapy?

• A. Movement of fluids along boundaries of cell membrane (unidirectional)
• B. Unidirectional flow unrelated to membranes
• C. Increased membrane permeability in all directions
• D. No effect on healing

Answer: (A)

Acoustic microstreaming creates a steady, small-scale fluid motion around oscillating structures in an ultrasound field. This motion is strongest near boundaries, such as cell membranes, where the vibrating microbubbles or boundaries drive tangential (along the surface) flow of the surrounding fluid. Because this flow adheres to the membrane boundary, it manifests as unidirectional movement of fluid along the membrane, generating shear forces that can enhance transport of nutrients, waste, or therapeutic agents at the membrane surface. That’s why the best answer describes movement of fluids along boundaries of the cell membrane in a unidirectional way. It isn’t a general flow unrelated to membranes, and while microstreaming can influence permeability locally, it isn’t an isotropic or all-directions increase in permeability. It also contradicts the notion of having no effect on healing, since the localized transport and mechanical effects can impact tissue responses.

Acoustic microstreaming creates a steady, small-scale fluid motion around oscillating structures in an ultrasound field. This motion is strongest near boundaries, such as cell membranes, where the vibrating microbubbles or boundaries drive tangential (along the surface) flow of the surrounding fluid. Because this flow adheres to the membrane boundary, it manifests as unidirectional movement of fluid along the membrane, generating shear forces that can enhance transport of nutrients, waste, or therapeutic agents at the membrane surface.

That’s why the best answer describes movement of fluids along boundaries of the cell membrane in a unidirectional way. It isn’t a general flow unrelated to membranes, and while microstreaming can influence permeability locally, it isn’t an isotropic or all-directions increase in permeability. It also contradicts the notion of having no effect on healing, since the localized transport and mechanical effects can impact tissue responses.