Koelis SAS

La Tronche, France

Koelis SAS

La Tronche, France
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Sarrazin J.,KOELIS SAS | Promayon E.,University Grenoble Alpes | Baumann M.,KOELIS SAS | Troccaz J.,University Grenoble Alpes
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS | Year: 2015

3D UltraSound (US) probes are used in clinical applications for their ease of use and ability to obtain intra-operative volumes. In surgical navigation applications a calibration step is needed to localize the probe in a general coordinate system. This paper presents a new hand-eye calibration method using directly the kinematic model of a robot and US volume registration data that does not require any 3D localizers. First results show a targeting error of 2.34 mm on an experimental setup using manual segmentation of five beads in ten US volumes. © 2015 IEEE.

Martin S.,CNRS Complex Medical Engineering Laboratory | Baumann M.,CNRS Complex Medical Engineering Laboratory | Baumann M.,Koelis SAS | Daanen V.,Koelis SAS | Troccaz J.,CNRS Complex Medical Engineering Laboratory
2010 7th IEEE International Symposium on Biomedical Imaging: From Nano to Macro, ISBI 2010 - Proceedings | Year: 2010

The poor signal-to-noise ratio in transrectal ultrasound (TRUS) images makes the fully automatic segmentation of the prostate challenging and most approaches proposed in the literature still lack robustness and accuracy. However, it is relatively straightforward to obtain high quality segmentations in magnetic resonance (MR) images. In the context of MR to TRUS data fusion the information gathered in the MR images can hence provide a strong prior for US segmentation. In this paper, we describe a method to non-linearly register a patient specific mesh of the prostate build from MR images to TRUS volume. The MR prior provides shape and volume constraints that are used to guide the MR-to-TRUS surface deformation, in collaboration with a US image contour appearance model. The anatomical point correspondences between the MR and TRUS surfaces are obtained implicitly. The method was validated on 30 pairs of MR/TRUS patient exams and achieves a mean Dice value 0.85 and a mean surface error of 2.0 mm. © 2010 IEEE.

Vitrani M.-A.,University Pierre and Marie Curie | Troccaz J.,TIMC laboratory | Silvent A.-S.,Grenoble University Hospital Center | Selmi S.Y.,TIMC laboratory | And 13 more authors.
IRBM | Year: 2015

The PROSBOT project aims to improve the clinical gesture of prostate biopsy sampling through a pedagogic simulator and a robotic assistance system. The objective of the simulator is to improve the learning curve of systematic and targeted prostate biopsy acquisition through realistic simulations of the gesture and a multitude of pedagogic modules. This paper reports the developed versions of the simulator and their evaluation. The robotic assistance system, called Apollo, is a co-manipulated robotic probe holder that aims at improving the clinical gesture through several functions, amongst which are: a) locking the probe in a target position, b) providing haptic feed-back to reduce gland deformation and c) gravity compensation. Two cadaver studies have shown that the device does not negatively impact or disturb the clinical gestures (transparency), but that gravity compensation improves the ergonomics of the gesture and that the locking function helps considerably at maintaining a stable position during puncture. A clinical study is currently ongoing with the objective to prove that biopsy accuracy can be improved with the robot, both for systematic and targeted sampling. Finally, the Apollo project is in an advanced stage of industrialization and will become commercially available. The possibilities for industrialization of the simulator are currently evaluated through a follow-up study. © 2015 Elsevier Masson SAS.

Hungr N.,CNRS Mathematics Laboratory | Baumann M.,CNRS Mathematics Laboratory | Baumann M.,Koelis SAS | Long J.-A.,CNRS Mathematics Laboratory | And 3 more authors.
IEEE Transactions on Robotics | Year: 2012

This paper describes a new 3-D ultrasound robotic prostate brachytherapy system. It uses a stationary 3-D ultrasound probe rigidly fixed to a robotic needle insertion mechanism. The novelty of the system is its ability to track prostate motion intraoperatively to allow the dose planning and needle trajectories or depths to be adapted to take into account these motions. Prostate tracking is done using a fast 3-D ultrasound registration algorithm previously validated for biopsy guidance. The 7-degree-of-freedom (7-DOF) robot and ultrasound probe are calibrated together with an accuracy of 0.9mm, allowing the needles to be precisely inserted to the seed targets chosen in the reference ultrasound image. Experiments were conducted on mobile, deformable synthetic prostate phantoms using a prototype laboratory system. Results showed that, with prostate motions of up to 7mm, the system was able to reach the chosen targets with less than 2-mm accuracy in the needle insertion direction. This measured accuracy included extrinsic measurement errors of up to 1.1mm. A preliminary cadaver feasibility study was also described in preparation for more realistic experimentation of the system. © 2012 IEEE.

Selmi S.-Y.,CNRS Complex Medical Engineering Laboratory | Promayon E.,CNRS Complex Medical Engineering Laboratory | Sarrazin J.,CNRS Complex Medical Engineering Laboratory | Sarrazin J.,KOELIS SAS | Troccaz J.,CNRS Complex Medical Engineering Laboratory
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Realistic medical procedure simulators improve the learning curve of the clinicians if they can reproduce real conditions and use. This paper describes the improvement of a transrectal ultrasound guided prostate biopsy simulator by adding the simulation of real-time prostate movements and deformations. A discrete bio-mechanical model is used to modify a 3D texture of an ultrasound image volume in order to quickly simulate the actual displacements and deformations. This paper describes this model and presents how the mesh deformation is used to induce the UltraSound volume deformation. The validation of the method is based on both a quantitative and a qualitative assessment. Experimental images acquired on a phantom are compared using mutual information metrics to the resulting generated images. This comparison shows that the proposed method offers realistic deformed 3D ultrasound images at interactive time. The method was successfully integrated to improve the transrectal ultrasound simulator. © Springer International Publishing Switzerland 2014.

Baumann M.,CNRS Complex Medical Engineering Laboratory | Baumann M.,Koelis SAS | Mozer P.,La Pitie Salpetriere Hospital | Daanen V.,Koelis SAS | Troccaz J.,CNRS Complex Medical Engineering Laboratory
Medical Image Analysis | Year: 2012

Transrectal biopsies under 2D ultrasound (US) control are the current clinical standard for prostate cancer diagnosis. The isoechogenic nature of prostate carcinoma makes it necessary to sample the gland systematically, resulting in a low sensitivity. Also, it is difficult for the clinician to follow the sampling protocol accurately under 2D US control and the exact anatomical location of the biopsy cores is unknown after the intervention. Tracking systems for prostate biopsies make it possible to generate biopsy distribution maps for intra- and post-interventional quality control and 3D visualisation of histological results for diagnosis and treatment planning. They can also guide the clinician toward non-ultrasound targets. In this paper, a volume-swept 3D US based tracking system for fast and accurate estimation of prostate tissue motion is proposed. The entirely image-based system solves the patient motion problem with an a priori model of rectal probe kinematics. Prostate deformations are estimated with elastic registration to maximize accuracy. The system is robust with only 17 registration failures out of 786 (2%) biopsy volumes acquired from 47 patients during biopsy sessions. Accuracy was evaluated to 0.76 ± 0.52. mm using manually segmented fiducials on 687 registered volumes stemming from 40 patients. A clinical protocol for assisted biopsy acquisition was designed and implemented as a biopsy assistance system, which allows to overcome the draw-backs of the standard biopsy procedure. © 2011 Elsevier B.V.

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