Anomalous Fissural Anatomy of the Right Lung as Observed in a Cadaveric Dissection.

BACKGROUND

Pulmonary fissures are anatomical structures of great anatomical, radiological and surgical importance. They delineate lung lobes and bronchopulmonary segments. Subsegmental lobulations and complex multi-fissural anomalies remain very rare.

CASE REPORT: Gross anatomical examination of the right lung of an adult female cadaver revealed a complete accessory fissure between the apical bronchopulmonary section and the hilum from the anterior boundary (5 cm from the apex, at the impression of the superior vena cava). The incomplete oblique fissure formed two upper lobe lobules from the hilum to the horizontal fissure. A Y-shaped incomplete fissure through the middle lobe from the oblique fissure to the horizontal fissure and hilum produced two lobules (superior, 2.5×2×1cm; inferior, 3×2×1cm). The oblique fissure was focally incomplete and the horizontal fissure was broadly obliterated. Craig and Walker's scores fluctuated within individual cracks.

DISCUSSION: The Y-shaped bifurcation of the middle lobe is proposed to be associated with an ectopic FGF-10 cluster and these pathologies are related to disrupted embryological signalling, particularly deregulation of the FGF-10, SHH, BMP4 and Wnt pathways.

CONCLUSION

The right lung with this unique combination of subsegmental lobulation, partial standard fissures and accessory fissures is probably genetically and embryologically based. Understanding of these differences is pertinent to endobronchial valve therapy, surgical planning and radiographic interpretation.