Experimental Computed Tomography-guided Vena Cava Puncture in Pigs for Percutaneous Brachytherapy of Middle Mediastinal Lymph Node Metastases

Abstract

Background:Percutaneous brachytherapy is a valuable method for the treatment of lung cancer and mediastinal lymph nodes metastasis. However, in some of the metastatic lymph nodes in the middle mediastinum, the percutaneous approach cannot be used safely due to possible damage to surrounding anatomical structures. We established an animal model (group of 12 pigs) to assess the safety and feasibility of computed tomography (CT)-guided vena cava puncture.Methods:Under CT guidance, an 18G needle was used to puncture the anterior wall of the anterior vena cava (AVC) in 12 pigs. The 18G needle was chosen as it is similar in size to the needles employed for clinical application in brachytherapy. The incidence of complications and vital signs was monitored during the procedure. Thoracotomy was performed to remove AVC specimens, which were analyzed for histological evidence of vessel wall damage and repair.Results:Following postoperative enhanced CT, two animals were found to have a small pneumothorax (one being hemopneumothorax). The intraoperative oxygen saturation of both animals was not significantly decreased and was maintained at 93–100%. No animals developed mediastinal hematoma. Preoperative, intraoperative, and postoperative changes in blood pressure, heart rate, hemoglobin, and blood oxygen saturation were not significant. Histological evaluation of AVC specimens showed that by 7 days following the procedure, the endothelial layer was smooth with notable scar repair in the muscularis layer.Conclusions:CT performed after the procedure and histological preparations confirmed the safety of the procedure. This indicates that percutaneous brachytherapy for metastatic middle mediastinal lymph nodes can be carried out via the superior vena cava.

CT-guided trans-sternal 125I seeds implantation for masses in the anterior or middle mediastinum

“…Only one patient experienced a small amount of pleural cavity bleeding. For some patients with metastases in the middle or upper posterior, trans-superior vena cava and trans-tracheal approaches were also reported to be safe by Liu and Lei [25][26][27]. It is well-known that via the sternum is considered to be a safe approach for CT-guided percutaneous needle biopsy of mediastinal nodules [2,11].…”

125Iodine brachytherapy via a trans-superior vena cava approach in patients with metastases in middle mediastinal lymph nodes: a novel approach

“…We created an animal model and assessed it in 12 pigs. Under CT guidance, an 18‐gauge needle was used to puncture the anterior wall of the anterior vena cava (nomenclature in these animals); we established that this approach is feasible and safe . Encouraged by the results, we performed trans‐SVC brachytherapy in a cohort of patients with metastases in middle mediastinum lymph nodes that could not be treated with conventional approaches for brachytherapy.…”