MOTORIZING AND OPTIMIZING ULTRASOUND STRAIN ELASTOGRAPHY FOR DETECTION OF INTRAUTERINE GROWTH RESTRICTION PREGNANCIES

作者：Saw Shier Nee; Low Jess Yi Ru; Mattar Citra Nurfarah Zaini; Biswas Arijit; Chen Lujie; Yap Choon Hwai

来源：Ultrasound in Medicine and Biology, 2018, 44(3): 532-543.

DOI：10.1016/j.ultrasmedbio.2017.12.007

• Motorized ultrasound strain elastography
• External polymeric reference layer
• Placental mechanical properties
• Intrauterine growth restriction

Intrauterine growth restriction is a prevalent disease in pregnancy in which placental insufficiency leads to 5 to 10 times higher mortality and lifelong morbidities. The current detection rate is poor, and recently, ultrasound strain elastography (USEL) was proposed as a new diagnostic technique. Currently, placental USEL uses maternal subcutaneous fat as the reference layer, but this is not ideal as fat tissue stiffness can vary widely between subjects. Current USEL also uses manual palpation, and under different compression depths and rates, viscoelastic tissues such as placenta can yield different stiffness results. In the study described here, we strove to improve placental USEL by (i) using an external polymeric pad of known stiffness as the reference layer and (ii) adopting motorized control of the transducer during UM, to standardize palpation motion. Results indicated that motorized USEL reduced measurement variability by 67% compared with freehand USEL. Satisfactory and statistically significant correlations between USEL measurements and mechanical testing validation results were obtained for our new USEL protocol. Placental tissues were found to be non-linear and viscoelastic in nature and, thus, differed in stiffness at different compression rates and depths. Our study also revealed that there was a specific compression depth and rate during USEL that provided better correlation to mechanical testing, and should be considered in clinical placental USEL.

• 出版日期2018-3