Uncommon Observation of a Trilobed Left Lung: A Cadaveric Case Report on Pulmonary Anatomical Variation and Its Embryological, and Clinical Perspectives

We present a rare case of a trilobed left lung, where the left lung possesses three distinct lobes separated by both horizontal and oblique fissures, mirroring the typical structure of the right lung. This anatomical variation was discovered during a routine cadaveric dissection at Nnamdi Azikiwe University. The study aims to document and describe this variation, compare it with classical lung anatomy, explore potential embryological causes, and highlight its clinical relevance. The discovery of this variation has significant implications for clinical practice, particularly in radiological diagnosis, thoracic surgery, and pulmonology. Recognizing such variations is crucial to avoid diagnostic errors, surgical complications, or misinterpretation in imaging. This case reinforces the importance of cadaveric dissection in anatomical education and highlights the need for region-specific anatomical documentation.