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Saint-Clément-de-la-Place, France

Diana M.,Institute for Image Guided Surgery
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2016

Pre-anastomotic bowel perfusion is a key factor for a successful healing process. Clinical judgment has limited accuracy to evaluate intestinal microperfusion. Fluorescence videography is a promising tool for image-guided intraoperative assessment of the bowel perfusion at the future anastomotic site in the setting of minimally invasive procedures. The standard configuration for fluorescence videography includes a Near-Infrared endoscope able to detect the signal emitted by a fluorescent dye, more frequently Indocyanine Green (ICG), which is administered by intravenous injection. Fluorescence intensity is proportional to the amount of fluorescent dye diffusing in the tissue and consequently is a surrogate marker of tissue perfusion. However, fluorescence intensity alone remains a subjective approach and an integrated computer-based analysis of the over-time evolution of the fluorescence signal is required to obtain quantitative data. We have developed a solution integrating computer-based analysis for intra-operative evaluation of the optimal resection site, based on the bowel perfusion as determined by the dynamic fluorescence intensity. The software can generate a "virtual perfusion cartography", based on the "fluorescence time-to-peak". The virtual perfusion cartography can be overlapped onto real-time laparoscopic images to obtain the Enhanced Reality effect. We have defined this approach FLuorescence-based Enhanced Reality (FLER). This manuscript describes the stepwise development of the FLER concept. © 2016 SPIE. Source

Wu T.,French Institute of Health and Medical Research | Wu T.,University of Strasbourg | Wu T.,Kunming Medical University | Bour G.,Research Institute Against Digestive Cancer | And 27 more authors.
Human Gene Therapy Methods | Year: 2015

We evaluated the possibility of introducing a combination of six oncogenes into primary porcine hepatocytes (PPH) using a lentiviral vector (LV)-mediated gene transfer in order to develop a porcine hepatocellular carcinoma model based on autologous transplantation of ex vivo-transformed hepatocytes. The six oncogenes were introduced into three plasmids, hence enabling the production of LVs encoding a luciferase reporter gene and hTERT+p53DD, cyclinD1+CDK4R24C, and c-mycT58A+HRasG21V genes, respectively. In order to improve the protection of the laboratory personnel manipulating such LVs, we used a compact cell culture cassette (CliniCell® device) as a closed cell culture system. We demonstrated that the CliniCell device allows to produce LVs, through plasmid transfection of 293T cells, and, after transfer to a second cassette, to transduce PPH with a similar efficacy as conventional open cell culture systems such as flasks or Petri dishes. Additionally, it is possible to cryopreserve at -80°C the transduced cells, directly in the CliniCell device used for the transduction. In conclusion, the use of a closed culture system for the safe handling of oncogene-encoding LVs lays the foundation for the development of porcine tumor models based on the autologous transplantation of ex vivo-transformed primary cells. © Copyright 2015 Mary Ann Liebert, Inc. Source

Liu Y.-Y.,Research Institute Against Cancer of the Digestive System | Liu Y.-Y.,Chang Gung University | Pop R.,Institute for Image Guided Surgery | Diana M.,Research Institute Against Cancer of the Digestive System | And 6 more authors.
Surgical Endoscopy and Other Interventional Techniques | Year: 2016

Background: Despite intensive preoperative localization workouts, intraoperative localization of the bleeding source in case of obscure gastrointestinal bleeding (OGIB) can be cumbersome and time-consuming. Our aim was to assess the feasibility of image-guided laparoscopic identification of the small bowel loop containing the bleeding source with and without near-infrared angiographic enhancement. Materials and methods: Angiography of superior mesenteric artery (SMA) branches was performed in 11 pigs using a right femoral artery approach, followed by a three-port laparoscopy, using a near-infrared-equipped laparoscope. Two pigs were used to identify the optimal intra-arterial indocyanine green (ICG) dose. Eight pigs were divided into two groups: ICG near-infrared angiography-assisted laparoscopy (n = 4) and fluoroscopic-assisted laparoscopy (n = 4). Finally, in one pig, a novel OGIB model was created and used to evaluate the ICG enhancement pattern in the presence of active bleeding. Results: Mean time to identify the fluorescence signal from the small bowel segment fed by the catheterized SMA branch was 13.75 ± 7.8 s, which was statistically significantly shorter than the time required to identify the tip of the catheter by fluoroscopic guidance, i.e., 243.25 ± 107 s (p = 0.02). Conclusions: Near-infrared fluorescence angiography using intra-arterial ICG injection provides a fast image-guided intraoperative localization of the small bowel loop fed by the arterial territory identified as bleeding by digital subtraction angiography and could help target the bleeding source during OGIB surgery. © 2015, Springer Science+Business Media New York. Source

Diana M.,Institute for Research against Cancer of the Digestive System | Diana M.,Institute for Image Guided Surgery | Usmaan H.,Institute for Image Guided Surgery | Legner A.,Institute for Image Guided Surgery | And 8 more authors.
Surgical Endoscopy and Other Interventional Techniques | Year: 2016

Introduction: Bile leakage is a serious complication occurring in up to 10 % of hepatic resections. Intraoperative detection of bile leakage is challenging, and concomitant blood oozing can mask the presence of bile. Intraductal dye injection [methylene blue or indocyanine green (ICG)] is a validated technique to detect bile leakage. However, this method is time-consuming, particularly in the laparoscopic setting. A novel narrow band imaging (NBI) modality (SPECTRA-A; Karl Storz, Tuttlingen, Germany) allows easy discrimination of the presence of bile, which appears in clear orange, by image processing. The aim of this experimental study was to evaluate SPECTRA-A ability to detect bile leakage. Methods: Twelve laparoscopic partial hepatectomies were performed in seven pigs. The common bile duct was clipped distally and dissected, and a catheter was inserted and secured with a suture or a clip. Liver dissection was achieved with an ultrasonic cutting device. Dissection surfaces were checked by frequently switching on the SPECTRA filter to identify the presence of bile leakage. Intraductal ICG injection through the catheter was performed to confirm SPECTRA findings. Results: Three active bile leakages were obtained out of 12 hepatectomies and successfully detected intraoperatively by the SPECTRA. There was complete concordance between NBI and ICG fluorescence detection. No active leaks were found in the remaining cases with both techniques. The leaking area identified was sutured, and SPECTRA was used to assess the success of the repair. Conclusions: The SPECTRA laparoscopic image processing system allows for rapid detection of bile leaks following hepatectomy without any contrast injection. © 2015, Springer Science+Business Media New York. Source

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