Fig. 2From: Preservation vs. dissection of inferior pulmonary ligament for thoracoscopic upper lobectomy: a prospective randomized controlled trialThree-dimensional lung volumetry. Semiautomated measurements of three-dimensional lung volumes were carried out using a reconstruction software (Mimics Research 21.0), utilizing Hounsfield unit (HU) values within the range of − 1024 to 500 HUBack to article page