ABSTRACT
PURPOSE: To demonstrate characteristic imaging findings in infradiaphragmatic extralobar pulmonary sequestration (IEPS) with special emphasis on ultrasound (US). MATERIALS AND METHODS: The imaging material (pre- and postnatal US in all cases, magnetic resonance imaging (MRI) in 2 cases) for 4 infants (3 girls, 1 boy) was reviewed. 2 patients underwent surgery (after birth and at 4 months of age, respectively) and the diagnosis of IEPS was confirmed. The other 2 patients were monitored conservatively using US for up to 15 months. RESULTS: All 4 left-side suprarenal masses exhibited the same characteristic sono-morphology, leading to the suspected diagnosis of IEPS. The masses were small (max. 10 ml), hyperechoic with cystic components and without calcifications, well demarcated and separate from the normal kidney and the suprarenal gland, and without any change in prenatal and directly postnatal size. Doppler US showed low-grade perfusion in all cases and an aberrant systemic artery originating from the abdominal aorta in 2 cases. MRI did not add any fundamental information. Despite the suspected imaging diagnosis of IEPS and negative urinalyses for neuroblastoma, 2 patients underwent surgery for histological confirmation. The lesions in the other 2 patients were monitored via US. A complete disappearance after 4 months in one patient and a continuous decrease in size over 15 months in the other patient were documented. CONCLUSION: Based on the characteristic findings of prenatal and postnatal US, IEPS can be diagnosed reliably. With the knowledge of its benign spontaneously regressing behavior, suspected suprarenal lesions should be treated conservatively via US monitoring.