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Yoshiharu Sakai - One of the best experts on this subject based on the ideXlab platform.

  • icg Fluorescence Imaging for quantitative evaluation of colonic perfusion in laparoscopic colorectal surgery
    Surgical Endoscopy and Other Interventional Techniques, 2017
    Co-Authors: Toshiaki Wada, Kenji Kawada, Suguru Hasegawa, Ryo Takahashi, Koya Hida, Mami Yoshitomi, Yoshiharu Sakai
    Abstract:

    Fluorescence technology with indocyanine green (ICG) provides a real-time assessment of intestinal perfusion. However, a subjective evaluation of Fluorescence intensity based on the surgeon’s visual judgement is a major limitation. This study evaluated the quantitative assessment of ICG Fluorescence Imaging in determining the transection line of the proximal colon during laparoscopic colorectal surgery. This is a retrospective analysis of a prospectively maintained database of 112 patients who underwent laparoscopic surgery for left-sided colorectal cancers. After distal transection of the bowel, the specimen was extracted extracorporeally and then the proximal colon was divided within the well-perfused area based on the ICG Fluorescence Imaging. We evaluated whether quantitative assessment of intestinal perfusion by measuring ICG intensity could predict postoperative outcomes: F max, T max, T 1/2, and Slope were calculated. Anastomotic leakage (AL) occurred in 5 cases (4.5%). Based on the Fluorescence Imaging, the surgical team opted for further proximal change of the transection line up to an “adequate” fluorescent portion in 18 cases (16.1%). Among the 18 patients, AL occurred in 4 patients (4/18: 22.2%), whereas it occurred in only 1 case (1/94: 1.0%) in the good perfusion patients who did not need proximal change of the transection line. The F max of the AL group was less than 52.0 in all 5 cases (5/5), whereas that of the non-AL group was in only 8 cases (8/107): with an F max cutoff value of 52.0, the sensitivity and specificity for the prediction of AL were 100 and 92.5%, respectively. Regarding postoperative bowel movement recovery, the T max of the early flatus group or early defecation group was significantly lower than that of the late flatus group or late defecation group, respectively. ICG Fluorescence Imaging is useful for assessing anastomotic perfusion in colorectal surgery, which can result in more precise operative decisions tailored for an individual patient.

  • evaluation of intestinal perfusion by icg Fluorescence Imaging in laparoscopic colorectal surgery with dst anastomosis
    Surgical Endoscopy and Other Interventional Techniques, 2017
    Co-Authors: Kenji Kawada, Suguru Hasegawa, Toshiaki Wada, Ryo Takahashi, Shigeo Hisamori, Koya Hida, Yoshiharu Sakai
    Abstract:

    Background Decreased blood perfusion is an important risk factor for postoperative anastomotic leakage (AL). Fluorescence Imaging with indocyanine green (ICG) provides a real-time assessment of intestinal perfusion. This study evaluated the utility of ICG Fluorescence Imaging in determining the transection line of the proximal colon during laparoscopic colorectal surgery with double stapling technique (DST) anastomosis.

Takeaki Ishizawa - One of the best experts on this subject based on the ideXlab platform.

  • liver transection using indocyanine green Fluorescence Imaging and hepatic vein clamping
    British Journal of Surgery, 2017
    Co-Authors: Yoshikuni Kawaguchi, Y Nomura, Motoki Nagai, D Koike, Y Sakuraoka, Takashi Ishida, Takeaki Ishizawa, N Kokudo, N Tanaka
    Abstract:

    Background Three-dimensional (3D) Imaging has facilitated liver resection with excision of hepatic veins by estimating the liver volume of portal and hepatic venous territories. However, 3D Imaging cannot be used for real-time navigation to determine the liver transection line. This study assessed the value of indocyanine green (ICG) Fluorescence Imaging with hepatic vein clamping for navigation during liver transection. Methods Consecutive patients who underwent liver resection with excision of major hepatic veins between 2012 and 2013 were evaluated using ICG Fluorescence Imaging after clamping veins and injecting ICG. Regional Fluorescence intensity (FI) values of non-veno-occlusive regions (FINon), veno-occlusive regions (FIVO) and ischaemic regions (FIIS) were calculated using luminance analysing software. Results Of the 21 patients, ten, four and seven underwent limited resection, monosegmentectomy/sectionectomy and hemihepatectomy respectively, with excision of major hepatic veins. Median veno-occlusive liver volume was 80 (range 30–458) ml. Fluorescence Imaging visualized veno-occlusive regions as territories with lower FI compared with non-veno-occlusive regions, and ischaemic regions as territories with no Fluorescence after intravenous ICG injection. Median FIIS/FINon was lower than median FIVO/FINon (0·22 versus 0·59; P = 0·002). There were no deaths in hospital or within 30 days, and only one major complication. Conclusion ICG Fluorescence Imaging with hepatic vein clamping visualized non-veno-occlusive, veno-occlusive and ischaemic regions. This technique may guide liver transection by intraoperative navigation, enhancing the safety and accuracy of liver resection.

  • applications of fusion Fluorescence Imaging using indocyanine green in laparoscopic hepatectomy
    Surgical Endoscopy and Other Interventional Techniques, 2017
    Co-Authors: Muga Terasawa, Takeaki Ishizawa, Yoshihiro Mise, Yosuke Inoue, Hiromichi Ito, Yu Takahashi, Akio Saiura
    Abstract:

    Indocyanine green (ICG)-Fluorescence Imaging has been developed for real-time identification of hepatic tumors and segmental boundaries during hepatectomy. Fusion ICG-Fluorescence Imaging (real-time visualization of pseudocolor-Fluorescence signals on white-light color images) may serve as a reliable navigation tool especially in laparoscopic hepatectomy, in which gross inspection and palpation are limited. The study population consisted of 41 patients undergoing laparoscopic hepatectomy. Hepatic tumors were identified by Fluorescence Imaging following the preoperative intravenous administration of ICG (0.5 mg/kg body weight). To visualize hepatic perfusion and segmental boundaries, ICG (1.25 mg) was injected intravenously during surgery, following closure of the proximal portal pedicle. A laparoscopic Imaging system, which enabled superimposition of the pseudocolor-Fluorescence images on white color images, was used for the fusion ICG-Fluorescence Imaging. Among the 53 malignant tumors resected, fusion ICG-Fluorescence Imaging revealed 45 nodules (85%), including three nodules of colorectal liver metastasis unidentifiable by white-light color images or intraoperative ultrasonography. It also delineated the segmental boundaries on the hepatic raw surfaces as well as on the phrenic/visceral surfaces in all 12 patients evaluated using this technique. Fusion Imaging enhances the feasibility of intraoperative ICG-Fluorescence Imaging in the identification of hepatic tumors and segmental boundaries. It may therefore help surgeons in the safe and accurate completion of laparoscopic hepatectomies.

  • visualization of subcapsular hepatic malignancy by indocyanine green Fluorescence Imaging during laparoscopic hepatectomy
    Surgical Endoscopy and Other Interventional Techniques, 2014
    Co-Authors: Hiroki Kudo, Takeaki Ishizawa, Keigo Tani, Nobuhiro Harada, Akihiko Ichida, Atsushi Shimizu, Junichi Kaneko, Taku Aoki, Yoshihiro Sakamoto, Yasuhiko Sugawara
    Abstract:

    Although laparoscopic hepatectomy has increasingly been used to treat cancers in the liver, the accuracy of intraoperative diagnosis may be inferior to that of open surgery because the ability to visualize and palpate the liver surface during laparoscopy is relatively limited. Fluorescence Imaging has the potential to provide a simple compensatory diagnostic tool for identification of cancers in the liver during laparoscopic hepatectomy. In 17 patients who were to undergo laparoscopic hepatectomy, 0.5 mg/kg body weight of indocyanine green (ICG) was administered intravenously within the 2 weeks prior to surgery. Intraoperatively, a laparoscopic Fluorescence Imaging system obtained Fluorescence images of its surfaces during mobilization of the liver. In all, 16 hepatocellular carcinomas (HCCs) and 16 liver metastases (LMs) were resected. Of these, laparoscopic ICG Fluorescence Imaging identified 12 HCCs (75 %) and 11 LMs (69 %) on the liver surfaces distributed over Couinaud’s segments 1–8, including the 17 tumors that had not been identified by visual inspections of normal color images. The 23 tumors that were identified by Fluorescence Imaging were located closer to the liver surfaces than another nine tumors that were not identified by Fluorescence Imaging (median [range] depth 1 [0–5] vs. 11 [8–30] mm; p < 0.001). Like palpation during open hepatectomy, laparoscopic ICG Fluorescence Imaging enables real-time identification of subcapsular liver cancers, thus facilitating estimation of the required extent of hepatic mobilization and determination of the location of an appropriate hepatic transection line.

  • mechanistic background and clinical applications of indocyanine green Fluorescence Imaging of hepatocellular carcinoma
    Annals of Surgical Oncology, 2014
    Co-Authors: Takeaki Ishizawa, Yoshikuni Kawaguchi, Junichi Kaneko, Koichi Masuda, Yasuteru Urano, Shouichi Satou, Kiyoshi Hasegawa, Junji Shibahara, Masashi Fukayama, Shingo Tsuji
    Abstract:

    Although clinical applications of intraoperative Fluorescence Imaging of liver cancer using indocyanine green (ICG) have begun, the mechanistic background of ICG accumulation in the cancerous tissues remains unclear. In 170 patients with hepatocellular carcinoma cells (HCC), the liver surfaces and resected specimens were intraoperatively examined by using a near-infrared Fluorescence Imaging system after preoperative administration of ICG (0.5 mg/kg i.v.). Microscopic examinations, gene expression profile analysis, and immunohistochemical staining were performed for HCCs, which showed ICG Fluorescence in the cancerous tissues (cancerous-type Fluorescence), and HCCs showed Fluorescence only in the surrounding non-cancerous liver parenchyma (rim-type Fluorescence). ICG Fluorescence Imaging enabled identification of 273 of 276 (99 %) HCCs in the resected specimens. HCCs showed that cancerous-type Fluorescence was associated with higher cancer cell differentiation as compared with rim-type HCCs (P < 0.001). Fluorescence microscopy identified the presence of ICG in the canalicular side of the cancer cell cytoplasm, and pseudoglands of the HCCs showed a cancerous-type Fluorescence pattern. The ratio of the gene and protein expression levels in the cancerous to non-cancerous tissues for Na+/taurocholate cotransporting polypeptide (NTCP) and organic anion-transporting polypeptide 8 (OATP8), which are associated with portal uptake of ICG by hepatocytes that tended to be higher in the HCCs that showed cancerous-type Fluorescence than in those that showed rim-type Fluorescence. Preserved portal uptake of ICG in differentiated HCC cells by NTCP and OATP8 with concomitant biliary excretion disorders causes accumulation of ICG in the cancerous tissues after preoperative intravenous administration. This enables highly sensitive identification of HCC by intraoperative ICG Fluorescence Imaging.

  • history and basic technique of Fluorescence Imaging for hepatobiliary pancreatic surgery
    2013
    Co-Authors: Takeaki Ishizawa, Norihiro Kokudo
    Abstract:

    Recently, Fluorescence Imaging using indocyanine green (ICG) has been used clinically to visualize the vascular/lymphatic anatomy and cancerous tissues in real time during surgery. Potentially, among the best indications for ICG Fluorescence Imaging are hepatobiliary and pancreatic diseases since not only the fluorescent property of ICG but also its biliary excretion property can be utilized for Imaging. In fact, ICG Fluorescence Imaging is already being used in clinical settings to identify the anatomy of the bile duct during laparoscopic surgery as well as open surgery in cases of liver cancer. 5-aminolevulinic acid is another fluorescent probe that has been administered to humans for identification of malignant glioma, bladder cancer and epidermal tumor, although its application to hepatobiliary and pancreatic diseases has rarely been evaluated. Preclinically, numerous kinds of novel fluorescent probes are being developed to improve the sensitivity and specificity of ICG Fluorescence Imaging, making in vivo Fluorescence Imaging one of the most active research fields in the world.

Vasilis Ntziachristos - One of the best experts on this subject based on the ideXlab platform.

  • real time intraoperative Fluorescence Imaging system using light absorption correction
    Journal of Biomedical Optics, 2009
    Co-Authors: George Themelis, Ralf Schulz, Vasilis Ntziachristos
    Abstract:

    We present a novel Fluorescence Imaging system developed for real-time interventional Imaging applications. The system imple- ments a correction scheme that improves the accuracy of epi- illumination Fluorescence images for light intensity variation in tissues. The implementation is based on the use of three cameras operating in parallel, utilizing a common lens, which allows for the concurrent collection of color, Fluorescence, and light attenuation images at the excitation wavelength from the same field of view. The correction is based on a ratio approach of Fluorescence over light attenuation im- ages. Color images and video is used for surgical guidance and for registration with the corrected Fluorescence images. We showcase the performance metrics of this system on phantoms and animals, and discuss the advantages over conventional epi-illumination systems de- veloped for real-time applications and the limits of validity of cor- rected epi-illumination Fluorescence Imaging. © 2009 Society of Photo-

  • real time intraoperative Fluorescence Imaging system using light absorption correction
    Journal of Biomedical Optics, 2009
    Co-Authors: George Themelis, Ralf Schulz, Jung Sun Yoo, Kwangsup Soh, Vasilis Ntziachristos
    Abstract:

    We present a novel Fluorescence Imaging system developed for real-time interventional Imaging applications. The system implements a correction scheme that improves the accuracy of epi-illumination Fluorescence images for light intensity variation in tissues. The implementation is based on the use of three cameras operating in parallel, utilizing a common lens, which allows for the concurrent collection of color, Fluorescence, and light attenuation images at the excitation wavelength from the same field of view. The correction is based on a ratio approach of Fluorescence over light attenuation images. Color images and video is used for surgical guidance and for registration with the corrected Fluorescence images. We showcase the performance metrics of this system on phantoms and animals, and discuss the advantages over conventional epi-illumination systems developed for real-time applications and the limits of validity of corrected epi-illumination Fluorescence Imaging.

Yasuhiro Honda - One of the best experts on this subject based on the ideXlab platform.

Cathie Ventalon - One of the best experts on this subject based on the ideXlab platform.

  • Fast confocal Fluorescence Imaging in freely behaving mice
    Scientific Reports, 2018
    Co-Authors: Clara Dussaux, Vivien Szabo, Yan Chastagnier, Jozsua Fodor, Jean-francois Leger, Laurent Bourdieu, Julie Perroy, Cathie Ventalon
    Abstract:

    Fluorescence Imaging in the brain of freely behaving mice is challenging due to severe miniaturization constraints. In particular, the ability to image a large field of view at high temporal resolution and with efficient out-of-focus background rejection still raises technical difficulties. Here, we present a novel fiberscope system that provides fast (up to 200 Hz) background-free Fluorescence Imaging in freely behaving mice over a field of view of diameter 230 μm. The fiberscope is composed of a custom-made multipoint-scanning confocal microscope coupled to the animal with an image guide and a micro-objective. By simultaneously registering a multipoint-scanning confocal image and a conventional widefield image, we subtracted the residual out-of-focus background and provided a background-free confocal image. Illumination and detection pinholes were created using a digital micromirror device, providing high adaptability to the sample structure and Imaging conditions. Using this novel Imaging tool, we demonstrated fast Fluorescence Imaging of microvasculature up to 120 μm deep in the mouse cortex, with an out-of-focus background reduced by two orders of magnitude compared with widefield microscopy. Taking advantage of the high acquisition rate (200 Hz), we measured red blood cell velocity in the cortical microvasculature and showed an increase in awake, unrestrained mice compared with anaesthetized animals.

  • A Fiberscope for Spatially Selective Photoactivation and Functional Fluorescence Imaging in Freely-Behaving Mice
    Optics in the Life Sciences, 2015
    Co-Authors: Cathie Ventalon, Vivien Szabo, Vincent De Sars, Jonathan Bradley, Valentina Emiliani
    Abstract:

    We demonstrate targeted photoactivation with near-cellular resolution and Fluorescence Imaging with optical sectioning in freely-behaving mice. Photoactivation patterns were produced with computer-generated holography and transmitted to the mouse using a fiber bundle.