Torsion of extralobar pulmonary sequestration: a case report.

Extralobar pulmonary sequestration (ELS) with torsion is rare in adolescents and mimics posterior mediastinal tumours, posing diagnostic challenges. An 11-year-old boy presented with acute chest pain. Contrast-enhanced computed tomography revealed a non-enhancing homogeneous mass with pleural effusion, while magnetic resonance imaging showed isointense T1 and hypointense T2 signals. Despite initial uncertainty regarding neoplasm, the acute presentation contrasted with the indolent course of posterior mediastinal tumours. History of abnormal prenatal ultrasonography facilitated diagnosis of torsed ELS. Video-assisted thoracoscopic surgery confirmed infarcted ELS with torsion, and the patient recovered uneventfully. This case highlights the importance of including ELS torsion in the differential diagnosis of posterior mediastinal masses and underscores the diagnostic value of prenatal imaging history.