SEPTAL STRUCTURE OF INCOMPLETE INTERLOBAR FISSURES OF THE LUNG

Rationale and Objectives. Some septal structures have been observed in the areas of incomplete interlobar fissures (IIFs) in resected lungs. We describe the anatomy of IIFs with or without the presence of septa l structures. Methods. Twenty fused areas from 16 autopsy cases were e xamined histologically. Other septal structures outside the areas of I IFs also were examined. Results. In 10 of the 20 fused areas, there wa s a mixture of septal structures with and without defects. In the rema ining 10, there were no septal structures. The septal structures consi sted of two inner layers from both lobes. Other septal structures exam ined were the same as ones observed in the IIFs. Conclusion. Linear sh adows seen at interlobar fissures and on computed tomography scans do not necessarily depict the presence of complete interlobar fissures. T he absence of linear shadows does not necessarily imply the absence of septal structures.