DISAPPEARING SUPRARENAL MASSES IN FETUSES AND INFANTS

This paper presents 12 infants (9 boys, 3 girls) in whom the diagnosis of a suprarenal mass (10 left, 2 bilateral) was made on antenatal son ography All were otherwise healthy neonates who were born at term afte r a normal pregnancy, labor and delivery. The masses ranged from 1 to 3.5 cm in diameter on initial scans at gestational ages of 19-35 weeks . Eleven masses were hyperechoic and 4 of these contained small, well- defined cysts. The 12th was hypoechoic. Follow-up sonography showed co mplete disappearance of the mass antenatally in 1 case and postnatally by 4-6 months in 5 cases; there was marked diminution in the size of the mass by 2 months of age in 4 infants, by 4 months in 1 case and by 15 months in 1 case. Eleven were managed nonoperatively. Laparotomy ( after disappearance of the mass) in the 12th case revealed only some f ibrous tissue. The 11 echogenic masses resemble previously reported im aging findings in infants with histologically proven intra-abdominal s equestrated lung. Conservative management with careful sonographic fol low-up should, therefore, be considered in otherwise healthy fetuses o r neonates with these imaging findings. We are less certain what the h ypoechoic mass represented.