<prompt> In Video assisted thoracoscopic surgery for better vision, the space in the operative field is created by :Self retaining retractorCO2 insufflationCollapse of ipsilateral lungRib spacing  <response>: Video Assisted Thoracoscopic Surgery VATS In contrast to most laparoscopic techniques, the working space for VATS is created not by adding an insufflating gas but rather by removing air from the ipsilateral lung parenchyma causing of the ipsilateral lung. Used for pulmonary decoication, pleurodesis, and lung or pleural biospies. Ref: Sabiston 20th edition Pgno: 355 