Intralobar Sequestration, Revisited

Excerpt

The identification of localized developmental abnormalities of the lung by prenatal ultrasonographic examination and their subsequent detailed pathologic examination has radically changed our understanding of their origin and progression [1, 2]. Of the developmental lung lesions so identified, none has been more controversial than intralobar sequestration, an entity I prefer to term “bronchial atresia with systemic vascular connection.” The now numerous reports of the in utero identification of such lesions should dispel any lingering notions that they are acquired lesions and not developmental malformations. Additionally, the description in such lesions of microcystic maldevelopment is quite widespread [3]. The fact that many of these reports are outside the pediatric pathology literature may have contributed to our delayed recognition of this striking association. This parenchymal change, beautifully illustrated in the article by Walford et al. in this issue (DOI: 10.1007/s10024-001-0194-z), has been identified frequently in the setting of bronchial atresia with or without systemic vascular connection, detected in utero or in early childhood. This finding suggests the likelihood of a malformation sequence with in utero airway obstruction/obliteration leading to microcystic parenchymal maldevelopment. Indeed, the frequent finding of identical parenchymal maldevelopment in extralobar sequestration [4] points to a common pathogenesis via airway obstruction/obliteration, rather than the coincidence of two separate developmental malformations. I like to call this the “bronchial atresia sequence.” …