Which form of cavitation is most likely to produce microstreaming in the intracellular fluid and shear stresses?

• A. Normal cavitation
• B. Stable cavitation
• C. Inertial cavitation
• D. Transient cavitation

Answer: (B)

Stable cavitation involves gas bubbles that oscillate in size in response to the ultrasonic field without collapsing. This continuous, rhythmic motion sets up a toroidal fluid flow around the bubble, called microstreaming, which generates shear stresses in the surrounding fluid, including intracellular fluid near cells. Because the bubble remains intact, the forces are steadier and more localized, producing mechanical stresses without the violent energy release seen in other forms.

Inertial or transient cavitation, by contrast, features rapid bubble growth and a violent collapse that creates shock waves and microjets—strong, abrupt forces that cause damage rather than sustained microstreaming. Normal cavitation is a broader term and doesn’t as specifically describe the streaming pattern associated with stable oscillations.