Coaxial projective imaging system for surgical navigation and telementoring

Abstract

A coaxial projective imaging (CPI) module acquires surgical scene images from the local site of surgery, transfers them wirelessly to the remote site, and projects instructive annotations to the surgical field. At the remote site, the surgical scene images are displayed, and the instructive annotations from a surgical specialist are wirelessly transferred back to the local site in order to guide the surgical intervention by a less experienced surgeon. The CPI module achieves seamless imaging of the surgical field and accurate projection of the instructive annotations, by a coaxial optical path design that couples the imaging arm with the projection arm and by a color correction algorithm that recovers the true color of the surgical scene. Our benchtop study of tele-guided intervention verifies that the proposed system has a positional accuracy of better than 1 mm at a working distance ranging from 300 to 500 mm. Our in vivo study of cricothyrotomy in a rabbit model proves the concept of tele-mentored surgical navigation. This is the first report of tele-guided surgery based on CPI. The proposed technique can be potentially used for surgical training and for telementored surgery in resourcelimited settings.

Bayesian analysis of depth resolved OCT attenuation coefficients

“…As recently noted by Liu 18 , the tail of the series in the denominator in Eq. ( 3 ), meaning all of the terms in the sum after some large term K , can be computed when an estimate for an attenuation coefficient at that point in the sample is available.…”

“…It is known that reconstruction artifacts 12 , 18 make the inferred coefficient unreliable near the deepest point of an A-scan. In practice, the reconstructed attenuation coefficient made from this approach must be discarded near the bottom of a scan and estimated using a different method 18 .…”

“…The DR approach assumes the material is weakly absorbing, making this technique related to voxelwise OCT scattering parameter inference methods 15 – 17 which have a long history in OCT signal processing. This method has been further refined by Liu 18 to better handle boundary effects caused by finite imaging depth. In either formulation, reconstructions of the attenuation coefficient will be highly variable due to the influence of speckle 14 .…”

Coaxial projective imaging for sentinel lymph node mapping in melanoma

“…To overcome these barriers, we have previously proposed an augmented reality (AR) coaxial projection imaging (CPI) technique, which allows surgeons to directly observe the surgical area with naked eyes. 7,8 This report evaluates the clinical feasibility of AR-CPI in melanoma SLNB.…”

Three-dimensional multimodal medical imaging system based on free-hand ultrasound and structured light

“…Recently, digital light processing (DLP) projectors have enabled fast and accurate structured light (SL) systems for 3D surface reconstruction. 6 Although primarily used in the manufacturing industry, 7 DLP-based SL systems have found new uses in biomedical applications such as in surgical navigation, 8 real-time 3D measurement otoscopy, 9 and fluorescence imaging and topography for intraoperative imaging. 10 It is by far the most adequate technique for obtaining a digital representation of the external surface.…”