The application of neonate lung ultrasound in congenital pulmonary airway malformation

Objective To analyze the characteristics of lung ultrasound (LUS) in congenital pulmonary airway malformation (CPAM), and to compare the difference of image characteristics between LUS and chest X-ray(CXR) and evaluate the value of neonate LUS in CPAM. Methods From June 2017 to October 2018, the characteristics of LUS and CXR of 32 neonates who were diagnosed with CPAM by prenatal ultrasound and postnatal chest CT were analyzed retrospectively, and the difference of their direct signs and indirect signs were compared. Results Among 32 CPAM cases, 10 cases (31.25%) showed a single large cystic lesions and 3 cases with consolidation, 4 cases (12.5%) characterized by multiple hypoechoic lesions and 3 cases with consolidation, 16 cases (50%) showed consolidation with or without intensiveaerated bronchus sign or dendritic air-filled bronchi, 2 cases (6.25%) only characterized by dense B-line. The non-characteristic sonographic findings including pleural line was not smooth and not clear; A-line decreased or disappeared, dense B-lines were observed. The ability of LUS in measuring the size of CPAM was limited.Among 32 CPAM cases, 10 cases (31.25%) showed large cystic hypoechoic lesions and 22 cases (68.75%) showed small cystic hypoechoic lesions by CT scan. In this group, there were 11 cases(34.4%) with normal CXR. There was no significant differences of the direct signs (including single large cystic lesions and multiple hypoechoic lesions) between LUS and CXR (P=0.80), however the indirect signs of LUS were more obvious than CXR, with significant difference(P=0.001). Conclusions The neonatal LUS findings of CPAM is multiple, it can be used as a preliminary qualitative screening method.The diagnosis value of indirect sign of LUS is superior to CXR. Key words: Ultrasonography; Lungs; Congenital pulmonary airway malformation; Computed tomography; Chest X-ray