In this retrospective study, investigators aimed to evaluate the effectiveness of the autologous blood patch method in percutaneous transthoracic lung biopsies performed with the coaxial technique. Biopsies and treatment modalities were performed according to approved guidelines. Ethics committee approval was obtained for the retrospective evaluation of the files and images of the participants. Written informed consent was obtained from all participants before biopsy procedures. Percutaneous transthoracic biopsies (PTB) have been started to be performed with the coaxial technique using the autologous blood patch method as of April 2019 in Interventional Radiology Department of Trakya University Hospital. All lung biopsies are performed using the blood patch method as a standard, as a clear decrease in procedural complications was observed in a short time. Thus, in this study, participants who underwent biopsy after April 2019 formed the participant group that underwent autologous blood patch, and those who had the procedure before this date formed the control group. Since autologous blood patch application was not performed before this date, participant grouping was time-dependent.

All participants included in the study underwent tru-cut biopsy with the coaxial technique. Of the 240 participants included in the study, 120 were treated with an autologous blood patch ( Group A), and the remaining 120 were participants without an autologous blood patch (Group B).

Procedure:

All biopsy procedures were performed by four interventional radiologists with at least 2 years of experience. First of all, after determining the lung lobe where the lesion was observed, axial CT images of 5 mm cross-section thickness were obtained so that the upper and lower parts of it could be visualized. After ruling the entry site in the skin, antisepsis and local anesthesia were performed. The coaxial system (17 G) was cautiously advanced and CT images were continuously evaluated to confirm entrance into the lesion. Approximately 3-4 pieces were taken with the 18 G core biopsy needle until sufficient tissue was obtained. In the autologous blood patch technique, approximately 6-7 ml of blood was taken from the participants with a 10 ml syringe before the procedure. By attaching a 3-way tap to the injector from which the blood is drawn, blood is drawn into a second injector to ensure that the clotted blood is dispersed and homogenized. After the above-mentioned procedures, and after sufficient tissue samples were taken at the last stage of the biopsy procedure, control CT imaging, including the whole lung, was performed to evaluate complications. The presences of pneumothorax were noted. The prepared autologous blood patch was given through the coaxial needle (approximately 1 ml of autologous blood patch was applied for every 1 cm when the coaxial needle was withdrawn) and the tract formed by the biopsy needle in the parenchyma, pleura, and under the skin was closed with the participant's autologous blood. Thus, it was aimed at preventing pneumothorax or reducing its severity if it occurred. The tract formed by the given autologous blood patch into the parenchyma can be observed in most biopsies. The lesion and lung parenchyma features, pneumothorax and other complications of the participants included in the study were evaluated through biopsy planning and follow-up images in hospital medical record system. It is known that transthoracic lung biopsies performed with the coaxial technique increase the diagnostic accuracy. In addition, by obtaining more than one tissue piece with a single entry, more tissue pieces can be sampled for histopathological studies as well as molecular and genetic analysis, which has become increasingly important recently. As a result, investigators think that the use of this method will increase, as more tissue material can be obtained in percutaneous transthoracic lung biopsies performed with coaxial technique and computed tomography using the autologous blood patch method, while reducing the risk of pneumothorax, the most common complication, at the same time.