Presentation
Dyspnoea at birth.
Patient Data
Chest radiograph at birth showed persistent focal lung consolidation at the right lower lung zone with surrounding interstitial opacity. No pleural effusion.
Normal thymus as anterior mediastinal mass. Feeding tube with the tip projected below left hemidiaphragm.
Well marginated focal lung consolidation at the posterobasal segment of right lower lung lobe. An aberrant systemic arterial supply to this abnormal focal lung consolidation which is directly arising from the abdominal aorta, above the origin of coeliac trunk (this is best appreciated on sagittal view). The venous drainage of this focal lung consolidation is into the left atrium via the right pulmonary vein.
Heart is not enlarged with grossly normal four heart chambers. Intact atrial and ventricular septum.
Annotated images showed the systemic arterial supply and pulmonary venous drainage.
Case Discussion
Extralobar pulmonary sequestration (ELS) is a subtype of pulmonary sequestration, which is usually encountered in neonate period. ELS usually presents in infancy with respiratory compromise.It develops as an accessory lung contained within its own pleura. Since it is enveloped in its own pleural sac, it rarely gets infected so almost always presents as a homogeneous soft tissue mass.
CT scans are the imaging modality of choice as it has 90% accuracy in the diagnosis of pulmonary sequestration. The most common appearance is a solid mass that may be homogeneous
or heterogeneous, sometimes with cystic changes. It is easier to delineate the systemic arterial supply and venous drainage with CT scan.
Ultrasound can be employed especially doppler studies which are helpful to identify the characteristic aberrant systemic artery that arises from the aorta and to delineate venous drainage.
MRI with MR angiography has its advantage for diagnostic purpose in addition to its non ionising radiation which is a plus for paediatric patients.