“…220 Mountney and colleagues, 224 Stoyanov and colleagues, 223 Lee and colleagues, 222 and Röhl and colleagues 221 typically used a stereoscopic endoscope to reconstruct organ surface using stereovision technique (needing a calibration step before the surgery begins). Mountney and colleagues, 227 Hu and colleagues, 225 Mahmoud and colleagues, 228 and Garcia and colleagues 226 proposed a solution to estimate the organ surface from the camera motion with simultaneous localization and mapping or structure from motion technique, the main idea being that parallax motion is sufficient to understand the scene shape. Other teams also use image information only, shading, 229,230 and shape assumption 231,232 (using conformal model), to estimate the organ surface with satisfactory results.…”