Lung lobes and fissures: a morphological study

Abstract

Objectives: Variations of lobar pattern and fissures of lung have been described on imaging techniques whereas there are fewer studies in gross anatomy. Present study was performed to examine lung specimens with respect to the morphology of fissures and lobes, to note the variations, to compare them with previous studies and to find their clinical implications.

Methods: Fifty pairs of lungs were used for the study, obtained from 50 formalin-fixed adult Indian cadavers. The lung specimens were meticulously observed for the patterns of lobes and fissures, variations were noted and specimens were photographed.

Results: Seven right lungs showed absence of horizontal fissure while one specimen showed absent oblique fissure. On the left side 6 specimens showed incomplete oblique fissure. In addition, 2 right-sided specimens showed presence of superior accessory fissure whereas the inferior accessory fissure was observed in 7 right and 12 left-sided specimens. The left minor fissure was seen in 13 specimens and one pair of lungs exhibited fissures separating all four segments seen on diaphragmatic surface.

Conclusion: The results and their comparison with the previous works show that there is a wide range of difference in occurrence of major, minor and accessory fissures between and among different populations. Knowledge of such variations might explain bizarre presentation of certain clinical cases pertaining to lung pathologies. Also knowing the frequency of occurrence of a variant fissure in a particular population might help the radiologist and clinician to make correct diagnosis, plan, execute and modify a surgical procedure depending on the merit of the case.

Keywords

• accessory fissure
• horizontal fissure
• lung
• oblique fissure