FIELD : medicine.SUBSTANCE : invention refers to medicine, namely pediatric oncology, surgery and radiation diagnostics, and can be used to select access when removing ganglioneureth mediastenum in children. In the preoperative period, the patients undergo computed thoracic tomography. Volume of tumor and volume of pleural cavity are measured, guided by results of tomography. A coefficient (K)=Vo/Vpp is calculated, where Vo is tumor volume, Vpp is volume of pleural cavity. At value K≤0.2 thoracoscopic approach is performed in patients, and thoracotomy if K>0.2.EFFECT : method provides optimization of surgical approach of children with mediastinal ganglioneuromes : open – thoracotomic – or thoracoscopic, as well as avoiding the cases of conversion into a thoracotomy when selecting a thoracoscopic approach by calculating a ratio of the tumor volume to the volume of the pleural cavity obtained by processing the computer tomography of the thoracic organs by X-ray digital images viewing application and Tumor Tracking system of PORTAL X-ray images storage systems of Philips company.1 cl, 2 ex