RT Book, Section
A1 Doherty, Gerard M.
SR Print(0)
ID 58108425
T1 Cystic Disease of Lungs, Congenital
T2 Quick Answers Surgery
YR 2010
FD 2010
PB The McGraw-Hill Companies
PP New York, NY
SN 
LK accesssurgery.mhmedical.com/content.aspx?aid=58108425
RD 2024/04/24
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)