“…However, except for a system using more expensive, proprietary hard- and software [ 14 , 15 ], depth-based surgical navigation could not translate into clinical practice yet because sensor accuracy and robustness are still unsatisfying, and the registration of the depth data to the anatomy is mainly achieved through conventional error-prone means (e.g., surface-based or point-based registration). For infrared-based ToF sensors, material dependent depth measurements have been identified as one major source of error [ 10 , 11 , 13 ]. More generally, comprehensive studies comparing depth accuracy of sensors using different technologies (structured light, ToF and active/passive stereoscopy) report ambiguous results between 0.6 mm and 3.9 mm error at 600 mm [ 16 , 17 , 18 ], which can be a realistic distance in a surgical environment.…”