A quantitative prediction of the post-operative lobectomy lung physiology using a GPU-based linear elastic lung biomechanics model and a constrained generative adversarial learning approach

Abstract

Lobectomy is a common and effective procedure for treating early-stage lung cancers. However, for patients with compromised pulmonary function (e.g. COPD) lobectomy can lead to major postoperative pulmonary complications. A technique for quantitatively predicting postoperative pulmonary function is needed to assist surgeons in assessing candidate’s suitability for lobectomy. We present a framework for quantitatively predicting the postoperative lung physiology and function using a combination of lung biomechanical modeling and machine learning strategies. A set of 10 patients undergoing lobectomy was used for this purpose. The image input consists of pre- and post-operative breath hold CTs. An automated lobe segmentation algorithm and lobectomy simulation framework was developed using a Constrained Adversarial Generative Networks approach. Using the segmented lobes, a patient-specific GPU-based linear elastic biomechanical and airflow model and surgery simulation was then assembled that quantitatively predicted the lung deformation during the forced expiration maneuver. The lobe in context was then removed by simulating a volume reduction and computing the elastic stress on the surrounding residual lobes and the chest wall. Using the deformed lung anatomy that represents the post-operative lung geometry, the forced expiratory volume in 1 second (FEV1) (the amount of air exhaled by a patient in 1 second starting from maximum inhalation), and forced vital capacity (FVC) (the amount of air exhaled by force from maximum inhalation), were then modeled. Our results demonstrated that the proposed approach quantitatively predicted the postoperative lobe-wise lung function at the FEV1 and FEV/FVC.