Vibration Analysis of Circular Membrane Model of Alveolar Wall in Examining Ultrasound-induced Lung Hemorrhage

BackgroundUltrasound-induced lung hemorrhage was analyzed from the perspective of alveolar resonance mechanism.MethodsThe alveolar resonance mechanism was theoretically studied by modeling the alveolar wall facet as a circular membrane model vibrating in fundamental mode. Based on the vibration analysis of this model, the equations of fundamental frequency and threshold pressure for the occurrence of ultrasound-induced lung hemorrhage were derived.ResultsThe validity of the circular membrane model of the alveolar resonance mechanism was demonstrated. This theoretical study predicts that ultrasound-induced lung hemorrhage does not occur when the total lung capacity is ≤20% (for mammals), and when the ultrasound frequency is >1.55 MHz at a mechanical index of ≤1.9 (for humans only).ConclusionThe alveolar resonance mechanism is a plausible mechanism of ultrasound-induced lung hemorrhage.