Impaired liver function, often caused by disease or anticoagulant therapy, can result in deficiencies of essential coagulation factors, including clotting Factor II. This underscores the importance of developing ultrasonic systems capable of detecting clotting factor deficiencies in plasma sample. This study explored the potential of an impulsive acoustic radiation force (IARF)-based ultrasonic system to assess plasma stiffness and distinguish between normal plasma and plasma deficient in coagulation Factor II. The system employed focused ultrasonic beams on a solid sphere, inducing microdisplacement when immersed in human plasma samples. An electrical signal with a frequency of 2.03406 MHz, amplitude of 118 VPP, and pulse repetition frequency of 1.249 Hz powered the ultrasonic transducer. Microdisplacement was monitored using an SR-9000 board operating in pulse-echo mode at 4.89 MHz. Experimental and theoretical microdisplacement curves were used to determine the shear modulus (μ) and time-to-peak displacement (TPD) of plasma samples during coagulation. For control plasma and plasma deficient in coagulation Factor II, μ values measured between 10 and 35 minutes after coagulation onset were 300.11 ± 14.55 Pa and 75.53 ± 2.91 Pa, respectively. Under the same conditions, TPD ranged from 4.86 ± 0.28 ms to 6.97 ± 0.35 ms. A statistically significant difference in μ and TPD values was observed between normal and Factor II-deficient plasma samples. Furthermore, the μ time-curve of prothrombin-deficient plasma exhibited a distinct pattern. These findings demonstrate the potential of the IARF-based ultrasonic system as a laboratory-scale research tool capable of detecting viscoelastic changes in small plasma volumes. While promising, further validation, particularly with larger sample sizes, standardized activation protocols, and clinical cohorts, is required before its applicability to diagnosing coagulation disorders or monitoring therapies can be established.
Costa-Júnior et al. (2026) studied this question.