Branching patterns and variations of the bronchus and blood vessels in the superior segment of the right lower lobe: a three-dimensional computed tomographic bronchography and angiography study

Shusheng Zhu; Wenzheng Xu; Zhihua Li; Weibing Wu; Alessandro Brunelli; Yosuke Matsuura; Giulio Maurizi; Davide Tosi; Ilies Bouabdallah; Dominique Gossot; Liang Chen

doi:10.21037/jtd-23-1607

Branching patterns and variations of the bronchus and blood vessels in the superior segment of the right lower lobe: a three-dimensional computed tomographic bronchography and angiography study

J Thorac Dis. 2023 Dec 30;15(12):6879-6888. doi: 10.21037/jtd-23-1607. Epub 2023 Dec 26.

Authors

Affiliations

¹ Department of Thoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
² Department of Thoracic Surgery, St. James's University Hospital, Leeds Teaching Hospitals NHS Trust, Leeds, UK.
³ Department of Thoracic Surgical Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
⁴ Division of Thoracic Surgery, "Sapienza" University of Rome, "Sant'Andrea" Hospital, Rome, Italy.
⁵ Thoracic Surgery and Lung Transplant Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
⁶ Department of Thoracic Surgery, Saint Joseph Hospital, Marseille, France.
⁷ Thoracic Department, Curie-Montsouris Thorax Institute - Institut Mutualiste Montsouris, Paris, France.

^# Contributed equally.

Abstract

Background: Superior segmentectomy is classified as simple due to the single intersegmental plane between the superior and basal segments. However, oncological outcomes in patients undergoing superior segmentectomy tend to be worse compared to those receiving other segmentectomy. The aim of this study is to determine the branching patterns and variations of the bronchus and blood vessels of the superior segment of the right lower lobe (RS⁶).

Methods: Three-dimensional computed tomographic bronchography and angiography (3D-CTBA) was reconstructed in 316 patients who underwent enhanced chest computed tomography (CT) and subsequent surgery in our center from November 2018 to March 2021.

Results: The bronchus in RS⁶ consisted of a single stem in 96.5% cases (305/316), and 2 separate stems in the remaining 3.5% cases (11/316). The artery in RS⁶ consisted of a single stem in 59.5% cases (188/316), 2 separate stems in 37.0% cases (117/316), and 3 separate stems in the remaining 3.5% cases (11/316). The vein in RS⁶ consisted of a single stem in 94.3% cases (298/316) and 2 separate stems in the remaining 5.7% cases (18/316). B⁶ variation was noted in 1.6% cases (5/316). A⁶ variation was noted in 18.0% cases (57/316), including the following: (I) coexistence of A⁶ and A² (n=25); (II) A⁶b originating from A⁹⁺¹⁰/A¹⁰ alone (n=20); (III) A⁶c originating from A⁹⁺¹⁰ (n=10); and (IV) co-draining of A⁶ and A⁷ (n=2). V⁶ variation was noted in 11.7% cases (37/316), including the following: (I) co-draining of V⁶ and V² (n=20); (II) co-draining of V⁶ and V⁴ (n=5); (III) V⁶ and V⁸⁺⁹ co-draining (n=3); (IV) V⁶ draining into the superior pulmonary vein (n=4); and (V) direct V⁶ draining into the left atrium (n=5).

Conclusions: Variation of A⁶ and V⁶ in RS⁶ is much more common than previously reported. 3D-CTBA reconstruction is useful for pre-surgery planning.

Keywords: Right lower lobe; anatomical variations; segmentectomy; superior segment; three-dimensional computed tomographic bronchography and angiography (3D-CTBA).