Imaging features of pulmonary artery involvement in Takayasu arteritis in children

Objective: To explore the imaging manifestation and the value of imaging follow-up in Takayasu arteritis with pulmonary artery involvement in children. Methods: The data of Takayasu arteritis with pulmonary artery involvement in 7 children in Children Hospital, Capital Institute of Pediatrics from July 2014 to June 2019, were summarized retrospectively, including 1 boy and 6 girls. There were 6 children under 1 year old, the age ranged from 2 to 7 months and the median age was 3 months old. Another child was 12 years old. CT images of all cases in the initial diagnosis and during the follow-up were reconstructed. The diameters and wall thickness of arteries were observed, including ascending aorta, main pulmonary artery, left and right pulmonary artery and each lobe pulmonary artery. The diameter ratio of main pulmonary artery to ascending aorta (MPA/AAO) was calculated. The pulmonary artery pressure, the diameters of left and right coronary artery were measured using echocardiography and compared in the initial diagnosis and during the follow-up. Results: All the 7 cases showed main pulmonary artery, left and right pulmonary artery widened, 6 cases showed lobe pulmonary arteries widened, 2 cases showed main pulmonary artery, left and right pulmonary artery wall thickened, and 6 cases showed lobe pulmonary arteries wall thickened. All the 7 cases showed MPA / AAO > 1 in the initial diagnosis, but only 1 case (12-year-old girl) presented pulmonary hypertension from echocardiography. All the 7 cases showed coronary artery dilated in different degrees and ranges in the initial diagnosis, including 3 cases with bilateral coronary artery dilatation and 4 unilaterally. Five children were followed up and showed improvement of pulmonary artery dilatation in 4 cases and progress in 1 case. MPA / AAO decreased in 4 cases and increased in 1 case. The pulmonary hypertension of the 12-year-old patient decreased during the follow-up, and the MPA / AAO also decreased from 1.64 to 1.01. Coronary artery dilatation decreased in 4 of 5 cases during the follow-up. Conclusion: CT imaging can clearly show pulmonary arteries, which plays an important role in the diagnosis and assessment of the treatment effect in Takayasu arteritis with pulmonary artery involvement in children. (authors)