Fig 3. Transverse and longitudinal section of the fetal thorax demonstrating a large microcystic congenital pulmonary airway malformation (CPAM) with mediastinal shift at 19 weeks of gestation.

CVR (CPAM volume ratio): 2.88 x 1.77 x 2.31 x 0.52/16.1 (head circumference) = 0.38.