It is usually encountered in infants, most being diagnosed before six months. It is more common in males (M:F 4:1).
Extralobar pulmonary sequestration is the less common type of pulmonary sequestration, accounting only for 15-25%.
ELS is covered by its own pleura and this is what differentiates ELS from ILS.
ELS receives vascular supply mainly from the aorta (thoracic or abdominal) or from other arterial vessels (splenic, subclavian, gastric, intercostal or multiple vessels) and venous drainage can be either systemic or pulmonary.
There is strong predilection towards the left lower lobe (65-90%).
- well marginated mass
- usually homogeneous, often without internal gas
- may contain cystic areas
- systemic arterial supply 4
Treatment and prognosis
Surgical excision is the mainstay of treatment.
- intralobar pulmonary sequestration: may not be able to differentiate from ELS on imaging
- bronchogenic cyst
Furthermore, in an infra-diaphragmatic location, consider 6:
- 1. Yilmaz A, Bektemur G, Ekinci GH et-al. Extralobar pulmonary sequestration: a case report. Monaldi Arch Chest Dis. 2014;79 (2): 90-2. Pubmed citation
- 2. Chen W, Wagner L, Boyd T et-al. Extralobar pulmonary sequestration presenting with torsion: a case report and review of literature. J. Pediatr. Surg. 2011;46 (10): 2025-8. doi:10.1016/j.jpedsurg.2011.07.017 - Pubmed citation
- 3. Donnelly LF. Pediatric Imaging. Saunders. (2009) ISBN:1416059075. Read it at Google Books - Find it at Amazon
- 4. Webb W. Thoracic Imaging. Lippincott Williams and Wilkins. ISBN:1451110898. Read it at Google Books - Find it at Amazon
- 5. Dail and Hammar's pulmonary pathology. Springer. ISBN:0387721398. Read it at Google Books - Find it at Amazon
- 6. Kalenahalli KV, Garg N, Goolahally LN, Reddy SP, Iyengar J. Infradiaphragmatic extralobar pulmonary sequestration: Masquerading as suprarenal mass. (2013) Journal of Clinical Neonatology. 2 (3): 146. doi:10.4103/2249-4847.120009 - Pubmed