Morphological variations of the lung: Accessory fissures and lobes

Anatomical variability in the human body is not as rare as was previously hypothesised. Indeed, as recently reviewed, the term 'norm' in anatomy can be considered an approximation. Thus, anatomical variations occur quite often, as largely demonstrated during non-invasive diagnosis, surgical intervention, or post mortem investigations. In the present study, we describe different anatomical variations in both the right and left lungs derived from cadavers of different ethnicities. The analysed organs were collected during dissection, and accessory lobes and fissures were observed in both the right and left lungs. Moreover, a horizontal fissure was missing from the right lung, resulting in only two lobes. Since lung anatomical variability is common in clinical practice and preclinical imaging studies can miss different morphologies, a deep and accurate knowledge of the anatomical variations of the lung is of extreme importance to avoid difficulties or changes during the surgical procedure.