In vivo visualization and ex vivo quantification of experimental myocardial infarction by indocyanine green fluorescence imaging

Abstract

Abstract:The fluorophore indocyanine green accumulates in areas of ischemia-reperfusion injury due to an increase in vascular permeability and extravasation of the dye. The aim of the study was to validate an indocyanine green-based technique of in vivo visualization of myocardial infarction. A further aim was to quantify infarct size ex vivo and compare this technique with the standard triphenyltetrazolium chloride staining. Wistar rats were subjected to regional myocardial ischemia (30 minutes) followed by reperfusion (n = 7). Indocyanine green (0.25 mg/mL in 1 mL of normal saline) was infused intravenously for 10 minutes starting from the 25th minute of ischemia. Video registration in the near-infrared fluorescence was performed. Epicardial fluorescence of indocyanine green corresponded to the injured area after 30 minutes of reperfusion. Infarct size was similar when determined ex vivo using traditional triphenyltetrazolium chloride assay and indocyanine green fluorescent labeling. Intravital visualization of irreversible injury can be done directly by fluorescence on the surface of the heart. This technique may also be an alternative for ex vivo measurements of infarct size.

Dual‐agent fluorescent labeling of soft‐tissue sarcomas improves the contrast based upon targeting both interstitial and cellular components of the tumor milieu

“…Unlike molecularly targeted agents, ICG and other perfusion agents collect in the interstitial spaces of the tumor, and fluorescence contrast arises from the differential of tissue clearance rather than differences in molecular expression. In addition, ICG has been found to localize in necrotic regions of normal tissue through association with lipoproteins and phosphoproteins 22,23 . This FGS technique provides improved contrast for longer periods compared to traditional ICG angiography and has been demonstrated in STS 4 .…”

“…In addition, ICG has been found to localize in necrotic regions of normal tissue through association with lipoproteins and phosphoproteins. 22,23 This FGS technique provides improved contrast for longer periods compared to traditional ICG angiography and has been demonstrated in STS. 4 In addition to its clinical relevance, ICG has a larger spectral overlap with ABY-029 than IRDye 700DX, with only~15 to 35 nm separation of fluorescence emission maxima depending on the environment.…”

Updated developments on molecular imaging and therapeutic strategies directed against necrosis

“…Detection of necrotic tissues and real-time image-guided surgery were successfully achieved in different organs of different animal models by ICG FLI 28. , 112. .…”

“…ICG was recently found to have ability to selectively bind to necrotic cells, which might be attributed to its interaction with lipoprotein and phospholipids 28 . Detection of necrotic tissues and real-time image-guided surgery were successfully achieved in different organs of different animal models by ICG FLI28., 112.. As a dye that has been approved by the U.S. Food and Drug Administration (FDA) for clinical applications, ICG potentially enable the use of optical imaging techniques for the clinical diagnosis and real-time image-guided surgical resection of necrosis-related diseases.…”

Fluorescent Nanoagents for Biomedical Applications

“…An example of this effect is the dimerization of ICG. In this case, it is possible to destroy dimers that are not capable of fluorescence by interacting with the blood protein-albumin [13].…”