Figure 21. Arrested acinar development in post-surfactant BPD. Schematics of a trio of acini show oversimplified anatomy due to alveolar paucity with either thin alveolar septa (center) or uniform mild fibrosis (right), compared with normal alveolar growth and development (left). (Illustration by Aletta Ann Frazier, MD, Department of Radiologic Pathology, Armed Forces Institute of Pathology.) (Adapted, with permission, from reference 85.)