Fetal lung volume in fetuses with urinary tract malformations: Comparison by 2D-, 3D-sonography and magnetic resonance imaging

Objective. To evaluate the concordance between two-dimensional ultrasonography (2DUS), three-dimensional ultrasonography (3DUS) and magnetic resonance imaging (MRI) in the assessment of lung volume in fetuses with urinary tract malformations (UTM).Methods. This was a cross-sectional study involving 12 pregnancies between 19 and 34 weeks, with various fetal UTM. Pulmonary volume was obtained by 2DUS using the following equation: total lung volume = [right lung antero-posterior diameter (X) x transverse diameter (Y) x cranial-caudal diameter x 0.152 + left lung (X1) x (Y1) x (Z1) x 0. 167]. Pulmonary volume by 3DUS was obtained using the virtual organ computer-aided analysis (VOCAL) method with a 30 degrees (VOL30), 18 degrees (VOL18) and 12 degrees (VOL12) rotation. A fast sequence of transverse lung section was also obtained by MRI. the intraclass correlation coefficient was used to evaluate the correlation between the three methods. the paired student t-test was used to compare the means.Results. There was a strong correlation between the three methods, and the highest correlations were between MRI and VOL18 for the right (ICC = 0.913) and left (ICC = 0.947) lungs. A strong correlation was also found between the lung volumes obtained through MRI and VOL12 as well as VOL18 (p = 0.544 and 0.286, respectively). However, for the left lung there was only a correlation between MRI and VOL12 (p = 0.49).Conclusions. There is a good concordance between 3DUS (VOL12) and MRI in the evaluation of lung volume in fetuses with UTM.Universidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imaging, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imaging, São Paulo, BrazilWeb of Scienc