==== Front Ann Saudi MedAnn Saudi MedAnnals of Saudi Medicine0256-49470975-4466King Faisal Specialist Hospital and Research Centre 1735631510.5144/0256-4947.2007.136asm-2-136What’s Your diagnosis?Diagnosis: Intralobar Sequestration Al-Khouzaie Thamer H. *Bukhari Medhat †AL Jameel Ahmed J. ‡Abdelaliam Awani A. §Division of Internal Medicine Services, Dhahran Health Center, Aramco, Dhahran, Saudi Arabia † Division of Surgical Services, Dhahran Health Center Aramco, Dhahran, Saudi Arabia ‡ Division of Internal Medicine Services, Dhahran Health Center, Aramco, Dhahran, Saudi Arabia § Division of Radiology Services, Dhahran Health Center, Aramco, Saudi ArabiaCorrespondence and reprint requests: Dr. T. Al-Khouzaie. Internal Medicine Services Division, Room A- 420-42, Dhahran Health Center, Aramco, DH, Saudi Arabia, T: (03) 877-3524, F: (03) 877-3790, thnerr@hotmail.comMar-Apr 2007 27 2 136 137 01 6 2006 Copyright © 2007, Annals of Saudi Medicine2007This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. ==== Body The chest CT scan with contrast (Figure 1) revealed large cystic parenchymal changes and a lesion with an aberrant aortic branch supplying the lesion. After a discussion of the risks and benefits of surgery with the patient, he elected surgical resection. At surgery, an intralobar sequestration (Figure 2) was found occupying almost all the right lower lobe with a feeding systemic arterial supply directly from the descending aorta along the inferior pulmonary ligament in the exact location shown on contrast CT (Figure 1), almost the size of the aorta. The pulmonary vein anatomy was normal, and the patient had a formal right lower lobectomy. DISCUSSION Pulmonary sequestration is a complex group of abnormalities involving the anomalous connection of the pulmonary parenchyma and the pulmonary and systemic vasculature. The term sequestration was first introduced by Pryce1 in 1946. Classically, the sequestration may be intra- or extralobar, according to the relationship to the normal lung parenchyma. Although diagnosed more frequently, pulmonary sequestration remains an extremely uncommon entity. Intralobar sequestration, however, is the most common form of pulmonary sequestration, accounting for 75% of cases. Over 50% of cases, however, become symptomatic after the age of 20 years.2 Arteriography is considered the gold standard for identification of the aberrant artery. Newer, less invasive imaging techniques are equally effective and safer alternatives to angiography. These include CT angiography, Doppler ultrasound, and magnetic resonance angiography (MRA). Color-enhanced, three-dimensional MRA can identify both the arterial and venous aberrancies and define the soft tissue abnormalities associated with sequestration.3,4 Multiplanar three-dimensional reconstruction of the CT angiogram can demonstrate the entire route of the anomalous vessel and define the consolidation of the sequestered lobe.5 These less invasive imaging techniques can provide additional information over traditional angiography and they should be used routinely in the preoperative evaluation of sequestrations. The differential diagnosis includes congenital or acquired lung cyst, tumors of the posterior mediastinum, Bochdalek hiatal hernia and congenital diaphragmatic cyst. Treatment of intralobar sequestration, whether symptomatic or not is lobectomy or segmentectomy.10,7 Wedge resection and control of an abnormal systemic artery is the operation of choice for extralobar sequestration.6,7 Figure 1 Contrast CT scan Figure 2 Gross pathology showing multicystic lessions filled with mucus. ==== Refs REFERENCES 1 Pryce DM Lower accessory pulmonary artery with intralobar sequestration of lung: A report of seven cases J Pathol 1946 58 457 67 2 Gustafson RA Murray GF WARDEN HE Hill RC Intralobar sequestration. A missed diagnosis ANN Thorac Surg 1989 47 841 7 2757438 3 Lehnhard S Wintere JT Uhrmeister P Pulmonary Sequestration: Demonstration of blood supply with 2D MR Angiography Eur J Radiol 2001 114 1326 8 4 Curros F Chigot V Emond S Sayegh N Revillon Y Scheinman P Role of embolization in the treatment of bronchopulmonary sequestraton Pediatr Radiol 2000 30 769 73 11100493 5 Ko SF Ng SH Lee TY Wan YL Liang CD Lin JH Noninvaseve imaging of brochopulmonary Sequestration AJR Am J Roentgennol 2000 175 1005 12 6 Mezzetti M Dell Agnola CA Bedoni M Cappelli R Fumagalli F Panigalli T Video-assisted thoracoscopic resection of pulmonary sequestration in ann infant Ann Thorac Surg 1996 61 1836 1838 8651801 7 Sugio K Kaneko S uokoyama H Ishida t Sugimachi K Hasuo K Pulmonary sequestration in older child and in adults Int Surg 1992 77 102 107 1644534 8 Zumbro GL Treasure RL Seitler G Strevey TE Brott W Green DC Pulmonary sequestration. A broad spectrum of bronchopulmonary foregut abnormalities Ann thorac Surg 1975 20 161 169 1164063