0000000000331700
AUTHOR
Peter G. Delaney
Molecular imaging of VEGF in gastrointestinal cancer in vivo using confocal laser endomicroscopy
Vascular endothelial growth factor (VEGF) is a therapeutic target in gastrointestinal cancer (GiC). However, its in vivo visualisation could not be achieved to date with endoscopic techniques. Confocal laser endomicroscopy (CLE) is a novel imaging technique for gastrointestinal endoscopy providing in vivo microscopy at subcellular resolution. The aim of the study was to evaluate CLE for in vivo molecular imaging of VEGF in GiC.Molecular imaging of tumours in APCmin mice, in xenograft models and in surgical specimens of patients with colorectal cancer (CRC) was achieved after application of labelled antibodies. The tumour sites were scanned with the probe for the strongest specific fluoresce…
In vivo confocal laser endomicroscopy of the human liver: a novel method for assessing liver microarchitecture in real time
Background and study aims Confocal endomicroscopy is a unique novel tool for in vivo histology in humans. Due to limitations imposed by the form of the equipment and by sterilization workflows, its use has been limited to the gastrointestinal tract so far. We have developed a rigid miniaturized probe for confocal endomicroscopy of the human liver during laparoscopy. Patients and methods To assess the feasibility and potential clinical value of this new system (diameter 6.3 mm), 25 patients with liver disease were examined during routine minilaparoscopy under conscious sedation. Results Subsurface serial images (from surface to 250 microm) were generated in real time after fluorescein inject…
In vivo confocal laser laparoscopy allows real time subsurface microscopy in animal models of liver disease.
Background/Aims Histopathology is essential in the diagnostic workup of most liver diseases. However, biopsy sampling might carry risks, is subject to sampling error, and does not provide dynamic tissue imaging. Therefore a newly developed miniaturised confocal probe was evaluated for in vivo microscopic imaging in rodent models of human liver diseases. Methods The handheld laparoscopy probe used a 488nm single line laser for fluorophore excitation. Optical slice thickness was 7μm, lateral resolution 0.7μm. Imaging depth was 0–250μm below the tissue surface. Imaging using different fluorescent staining protocols was performed in healthy mice, IFNγ- and IL-12-induced hepatitis, after bile du…
In Vivo Molecular Imaging of Somatostatin Receptors in Pancreatic Islet Cells and Neuroendocrine Tumors by Miniaturized Confocal Laser-Scanning Fluorescence Microscopy
The aim of the study was to evaluate real time in vivo molecular imaging of somatostatin receptors (sstrs) using a handheld miniaturized confocal laser scan microscope (CLM) in conjunction with fluorescein-labeled octreotate (OcF) in healthy mice and murine models of neuroendocrine tumors. For CLM a small rigid probe (diameter 7 mm) with an integrated single line laser (488 nm) was used (optical slice thickness 7 μm; lateral resolution 0.7 μm). OcF was synthesized via Fmoc solid-phase peptide synthesis and purified by HPLC showing high-affinity binding to the sstr2 (IC50 6.2 nmol). For in vitro evaluation, rat and human pancreatic cancer cells were used and characterized with respect to its…
Dynamic in vivo Imaging of Microvasculature and Perfusion by Miniaturized Confocal Laser Microscopy
<i>Introduction:</i> Microvasculature and associated pathologies mandate dynamic imaging. We evaluated a novel miniaturized confocal laser scanning probe for in vivo visualization of blood vessels, blood flow, cell tracking and perfusion in both healthy rodents and disease models.<i> Methods:</i> The hand-held confocal microscopy system allowed a 500- to 2,400-fold magnification at a dynamically variable imaging depth. Different intravital stains were used alone or in combination for tissue, nuclear, plasma and vascular endothelial cell staining and for blood flow visualization, and targeted staining for individual cell populations. <i>Results:</i> Precis…
Confocal laser endoscopy for diagnosing intraepithelial neoplasias and colorectal cancer in vivo
Background & Aims: Aconfocal laser endoscopy system has recently been developed that may allow subsurface imaging of living cells in colonic tissue in vivo. The aim of the present study was to assess its potential for prediction of histology during screening colonoscopy for colorectal cancer. Methods: Twenty-seven patients underwent colonoscopy with the confocal endoscope using acriflavine hydrochloride or fluorescein sodium with blue laser illumination. Furthermore, 42 patients underwent colonoscopy with this system using fluorescein sodium. Standardized locations and circumscript lesions were examined by confocal imaging before taking biopsy specimens. Confocal images were graded accordin…
In-vivo confocal real-time mini-microscopy in animal models of human inflammatory and neoplastic diseases
Background and study aims Although various improvements in tissue imaging modalities have recently been achieved, in-vivo molecular and subsurface imaging in the field of gastroenterology remains a technical challenge. In this study we evaluated a newly developed, handheld, miniaturized confocal laser microscopy probe for real-time in-vivo molecular and subsurface imaging in rodent models of human disease. Materials and methods The minimicroscope uses a 488-nm, single line laser for fluorophore excitation. The optical slice thickness is 7 microm, the lateral resolution 0.7 microm. The range of the z-axis is 0-250 microm below the tissue surface. Imaging was performed using different fluores…