Noninvasive Detection Of the Embryonic Abnormality Caused by Methylmercuric Chloride in Mammals Using Dual-Modality PA/US Imaging

Abstract

Background: Non-invasive detection of the chronic toxicity of methylmercury chloride (MMC) on the embryonic cardiovascular system is vital to embryo development as it can guide the clinical diagnosis. Although, the existing ultrasonic imaging methods can visualize the organ structure, they cannot accurately determine the hemoglobin content of the tissues. Therefore, it is vital to detect the structural and functional information of organs for improving the sensitivity of clinical diagnosis. Methods: We present a new approach of dual-modality photoacoustic/ultrasonic (PA/US) imaging to detect cardiotoxicityof MMC during the different embryo development stages in vivo. Findings: Our results showed the morphological abnormalities with the high dosage (HD) of MMC at E11.5. However, the same phenomenon was first detected at E14.5 for the low dosage (LD) of MMC，which was consistent with the sectioned pathological results. In addition, the quantitative functional analysis results showed that in the LD group, the PA, SaO2 and HbT signals in the embryonic heart area of mice at the E14.5 were significantly lower than those in the control group, which were 0.51-, 0.76-, and 0.66-fold of the control group, respectively. Furthermore, at E14.5 the volume of the embryonic heart of the LD group was 0.81-fold of the control group. Interpretation: This work suggests that dual-modality PA/US is a promising strategy for detecting congenital or acquired embryonic heart developmental defects in vivo, which can be expected to be further exploited for pre-clinical research of cardiovascular diseases (CVD) and congenital heart disease (CHD). Funding Statement: This work was partly supported by the National Science Foundation of China (81701743), Xiamen Science and Technology Plan Project (3502Z20183018). Declaration of Interests: The authors declare that they have no conflict of interest. Ethics Approval Statement: This study was conducted in accordance with the rules established by the Center for Molecular Imaging and Translational in Xiamen University. The protocol was approved by the Ethics Committee for Animal Experimentation of the Xiamen University.