1. A method, implemented on a computing device having at least one processor, storage, and a communication platform capable of connecting to a network for surgical procedure assistance, comprising: obtaining a first volume of air inside a lung based on a first image of the lung captured prior to a surgical procedure, wherein the lung has a first shape on the first image; capturing a video image of the lung during the surgical procedure; computing, via registering the captured video image with the first image, a second volume of air deflated from the lung; estimating a second shape of the lung based on the first shape of the lung, the first air volume inside the lung, and the second volume of air deflated from the lung, the second shape being estimated by condensing a plurality of voxels in the first image along a gravity direction; and updating a surgical plan based on the estimated second shape of the lung.