Uniportal video-assisted thoracoscopic isolated S4 segmentectomy of left upper lobe: a stepwise surgical technique

Sublobar anatomical resections are increasingly adopted for management of early-stage non-small cell lung cancer (NSCLC), particularly for peripheral tumors ≤2 cm, to maximize parenchymal preservation while maintaining oncologic outcomes comparable to lobectomy. This type of resection is also used for pulmonary metastasectomies or for the treatment of non-malignant lung lesions. This video demonstrates a uniportal video-assisted thoracoscopic surgery (UVATS) technique for anatomical resection of the superior lingular segment (S4), addressing unique anatomical and technical challenges inherent to this procedure. The superior lingular segment (S4) is characterized by deeply situated and variable segmental broncho-vascular structures that demand meticulous hilar dissection and precise identification prior to division. Key technical elements include optimized patient positioning and single-port access, systematic exposure of the hilum, careful isolation and controlled division of the targeted arterial branches and lingular bronchus using vascular staplers or energy devices, and parenchymal division guided by clear intersegmental plane identification. Adjunctive strategies such as selective bronchoscopic inflation/deflation, intravenous indocyanine green (ICG) fluorescence imaging, and use of anatomical landmarks are integrated to accurately delineate the intersegmental plane and to minimize margin compromise. Special attention is given to techniques for handling deeply located vessels to prevent hemorrhage, measures to reduce postoperative air leak, and methods for secure staple-line management to preserve adjacent lung. The uniportal approach offers a minimally invasive, reproducible method for anatomically precise isolated S4 segmentectomy, facilitating parenchymal sparing without sacrificing oncologic principles. Knowledge of segmental anatomy, familiarity with segmental identification tools, and adherence to defined technical steps are essential to safely perform this lung-sparing resection in appropriately selected patients.