TY - CHAP M1 - Book, Section TI - Cystic Disease of Lungs, Congenital A1 - Doherty, Gerard M. PY - 2010 T2 - Quick Answers Surgery AB - • Uncommon aberrations of respiratory tract development-Starts at 4th week of fetal life-Initial phase of airway branching until 16th wk-Canalicular phase: Capillaries develop (16th to 26th wk)-Alveolar phase: 26th wk on, alveolar air sacs form with type I, II pneumocytes• Tracheobronchial atresia (TA)-Can occur at any level-May involve isolated or multiple areas-Diffuse disease is fatal-Isolated bronchial atresia results in bronchus with blind pouch leads to compression of surrounding lung and emphysematous changes-Anomalous tracheal or esophageal bronchi and diverticular are related diseases• Bronchogenic cysts (BC)-Abnormal budding of foregut may result in formation of BC-Commonly occur in pulmonary hilum or mediastinum, occasionally pulmonary parenchyma-Usually single, lined by cuboidal respiratory epithelium, preferentially in lower lobes-Cysts generally thin walled, occasionally with cartilage-May communicate with tracheobronchial tree-Known to enlarge rapidly and rupture causing tension pneumothorax• Bronchopulmonary dysplasia (BPD): Cluster of diseases includes pulmonary agenesis, aplasia, and primary and secondary hypoplasia-Unilateral agenesis occurs when 1 lung and vessels fail to develop-Pulmonary aplasia: Blind bronchial tumor stump exists and soils normal lung with secretions-Pulmonary hypoplasia: Low radial alvelolar count and low lung to body weight ratio without inciting cause-Secondary pulmonary hypoplasia: Occurs due to fetal or maternal abnormalities such as congenital diaphragmatic hernia, oligohydramnios, Potter syndrome, abnormal bone development• Pulmonary sequestration (PS)-Abnormal budding of foregut leading to lung parenchyma without bronchial communication-Can be intralobar (85%) or extralobar-Often have systemic blood supply from abdominal aorta, 96% drain into pulmonary venous system• Cystic adenomatoid malformation (CAM)-Overgrowth of terminal bronchiolar structures lined by respiratory epithelium with disorganized elastic connective tissue and smooth muscle-Solid structures interspersed with cysts resembling immature alveoli• Congenital Lobar Emphysema (LE)-Hypoplastic bronchial cartilage in 25-75% of patients; increased alveoli number in 37% (polyalveoli)-Neonates with prolonged vent support may develop LE from catheter trauma and barotraumas, affecting right lower lobe (RLL) SN - PB - The McGraw-Hill Companies CY - New York, NY Y2 - 2024/03/29 UR - accesssurgery.mhmedical.com/content.aspx?aid=58108425 ER -