Segmental volumetric analysis with a ventilated or perfused area: identifying the intersegmental plane

Area of Science:

• Thoracic Surgery
• Pulmonary Medicine
• Medical Imaging

Background:

• Accurate identification of the intersegmental plane is crucial for segmentectomy.
• Current methods include inflation-deflation and indocyanine green (ICG) injection.
• The congruence between planes defined by ventilation and arterial supply is not well-established.

Purpose of the Study:

• To compare intersegmental planes defined by bronchial and arterial territories using 3D CT volumetry.
• To evaluate the accuracy of ICG method in defining surgical margins.

Main Methods:

• Retrospective analysis of 195 patients undergoing thoracoscopic segmentectomy.
• 3D CT reconstruction and volumetry to delineate bronchial and arterial territories.
• Paired t-test to compare segmental volumes and tumor distances.

Main Results:

• In upper lobe segmentectomies, arterial segmental volume was significantly smaller than bronchial volume (P < 0.001).
• No significant difference was found between arterial and bronchial volumes in lower lobe segmentectomies (P = 0.607).
• Tumor distance to the intersegmental plane was smaller based on arterial territories in upper lobes.

Conclusions:

• The indocyanine green method, based on arterial distribution, may underestimate the resected volume in upper lobe segmentectomies.
• Precise definition of intersegmental planes is critical for oncologic outcomes in segmentectomy.