Aberrant mediastinal basal pulmonary artery encountered at anatomical lung resection: A case report and review of the literature

INTRODUCTION

Abnormal branching of the pulmonary artery is often encountered in anatomical lung resection, which can potentially result in accidental vessel injury with life-threatening bleeding or extra lung resection. The mediastinal basal pulmonary artery (Arteria Praebronchialis, AP) is a very rare but potentially critical variant.

PRESENTATION OF CASE

We present the case of a patient with lung cancer accompanied by the left basal segmental pulmonary artery, independent A8a+9, which was liable to be injured during lower lobectomy with poor interlobar fissure development. This variation was preoperatively recognized using three-dimensional contrast-enhanced computed tomography (3D-CECT) angiography, and vessel injury was avoided.

DISCUSSION AND LITERATURE REVIEW

3D-CECT angiography was effective in identifying this rare but potentially critical variation, and it is desirable to perform it routinely before anatomical lung resection. A review of 31 AP cases revealed that the branching pattern of AP was independent (15 patients, 48 %) and common trunk type (16 patients, 52 %), one half for each. Mediastinal branching of the lingular artery was more frequent among the reported AP cases (71 %) than in general reports.

CONCLUSION

When mediastinal branches of left pulmonary artery are encountered, the possibility that it is AP should be always taken into account.

Mediastinal basal pulmonary artery identification and classification by three-dimensional reconstruction

PURPOSE

The primary objective of the present study was to use CT angiography and 3D reconstruction to assess and to classify the mediastinal pulmonary basal segmental arteries.

METHODS

We report a particular type of bifurcated left lower pulmonary artery, namely, the "mediastinal basal pulmonary artery" type, which is the first branch from the proximal the left pulmonary artery (LPA) between the left main bronchus (LMB) and the left superior pulmonary vein (LSPV) and proceeding directly into the lower lobe. There are many types of mediastinal basal pulmonary arteries, and these can be classified worldwide in a unified way and format, which will be beneficial for clinical records, annotation and academic exchange.

RESULTS

The mediastinal basal pulmonary arteries are described either as "supernumerary" when duplicating or "displaced" when replacing the normal arterial branching pattern of the lower lobe. The displaced type is more frequent than the supernumerary type. There are 12 types of left mediastinal basilar arteries.

CONCLUSION

This is the first report to categorize the mediastinal basal pulmonary artery, is the first to suggest a system for mediastinal basal pulmonary artery nomenclature, and creates simplified models for use when planning anatomical segmentectomy. Knowledge and recognition of this rare and special condition may facilitate better diagnosis and treatment of these patients.

The first rib hypoplasia and the aberrant pulmonary artery branch detected by three-dimensional computed tomography in a surgical case with apical lung cancer, a case report

Background

The complete resection is one of the most crucial requirements to achieve favorable outcomes in oncologic surgery. The apex of the lung is surrounded complicatedly by the clavicle, the first rib, the subclavian artery and vein, and the brachial plexus. Therefore, the image information especially about the infiltration of adjacent anatomic structures, facilitates the surgery in the apical lung cancer.

Case presentation

A 70-year-old man presented at our hospital with a computed tomography (CT) scan showing a tumor at the left lung apex that infiltrated the chest wall. Two anatomical anomalies were found, which were the first rib hypoplasia and the aberrant pulmonary artery branch. The three-dimensional (3D) CT enhanced with using bolus tracking method, simultaneously revealed that the subclavian vessels existed between the clavicle and the second rib, and the left lingual pulmonary artery and the ventrobasal pulmonary artery diverged from the left main pulmonary artery as the first branch. We diagnosed the tumor as a primary lung squamous cell carcinoma that infiltrated the second rib, because sputum cytology suggested squamous cell carcinoma. Left lung upper lobectomy with lymph node dissection and chest wall resection (the second and third ribs) were performed with caution for the anatomical anomalies. The pathological diagnosis was pleomorphic carcinoma (5.0 × 3.0 × 1.9 cm) that invaded the second costal bone, and the pathological stage was confirmed to be pT3N0M0. Pathologically curative resection was accomplished. The patient was discharged from the hospital on 10 days after surgery.

Conclusion

The 3D-CT precisely detected the anomalous structure consisted with the clavicle, the second rib, the subclavian artery and vein, the aberrant pulmonary artery branch. In the present case with the apical lung cancer, the evaluation of the anatomical structure via 3D-CT facilitated to achieve a pathological complete resection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12893-016-0199-1) contains supplementary material, which is available to authorized users.

Lobectomy for a mediastinal basal pulmonary artery

Anatomical variations of the pulmonary artery increase the risks for vessel injury and critical mistakes during pulmonary artery resection. The mediastinal basal pulmonary artery is a rare branch abnormality and is the first branch of the pulmonary artery to flow into the basal segment. We report a patient who underwent video-assisted thoracic surgery (VATS) right lower lobectomy for lung cancer with a mediastinal basal pulmonary artery. The mediastinal basal pulmonary artery was detected preoperatively by computed tomography. During VATS, this artery was found with careful dissection by dividing the lung parenchyma within the fissure, and right lower lobectomy was safely performed.