Intraoperative indocyanine green angiography for the objective measurement of blood flow

Abstract

PurposeIntraoperative assessment of tissue perfusion is important to predict wound healing or improvement of symptoms in patients with peripheral arterial disease (PAD) or vascular trauma. There is no widely accepted standard for intraoperative measurement of tissue perfusion. Here, we report the use of indocyanine green (ICG)-based angiography to determine the blood flow in patients with PAD and vascular trauma.MethodsThe SPY fluorescent imaging system was utilized. A dose of 3–5 mL of ICG (2.5 mg/mL) was injected intravenously followed by a 10 mL normal saline flush. The SPY imaging system was used to quantitatively assess perfusion. During the study period, the SPY imaging system was applied in 4 patients with PAD and one patient with vascular trauma.ResultsIn 3 patients with PAD associated with an ischemic wound, complete wound healing was achieved with the indication of viable tissue by the SPY system. In one patient with severe claudication in both lower extremities, the ICG angiography was used to determine the increased blood flow after revascularization. In the case of vascular trauma, this imaging system enabled the delineation of viability of the injured tissue.ConclusionICG angiography can determine the surface tissue viability in PAD patients. In cases of severe vascular trauma,the SPY system can be used to determine tissue perfusion. Further study is warranted to define the definite utility of this technology to assess perfusion, response to revascularization, and potentially, to predict the likelihood of wound healing.

Plasma flow distal to tourniquet placement provides a physiological mechanism for tissue salvage

“…However, the limitation of in vivo fluorescence imaging to small animals has prevented similar quantification in large animal models and humans in the same capacity. The recent development of portable NIR imaging devices such as the SPY and Fluobeam [25,26] have allowed us to confirm previous studies on residual plasma flow in https://doi.org/10.1371/journal.pone.0244236.g005…”

“…However, the limitation of in vivo fluorescence imaging to small animals has prevented similar quantification in large animal models and humans in the same capacity. The recent development of portable NIR imaging devices such as the SPY and Fluobeam [ 25 , 26 ] have allowed us to confirm previous studies on residual plasma flow in swine [ 6 ] move beyond prior studies to evaluate human blood flow in situ . This technology has demonstrated herein that 70% of human subjects with an extremity tourniquet in place also exhibit residual plasma flow and this flow directly correlated with MAP and BMI in volunteers.…”

Fluorescent angiography used as a tool to guide angiosome-directed endovascular therapy for diabetic foot ulcers

“…x 13.5 cm 2 , with image sequences at 3.75 to 30 frames per second depending on recording time ranging from 30 seconds to 4.5 minutes. 13,14 From this, values such as ingress, ingress rate (rate at which fluorescence intensity increases on imaging field), peak perfusion (i.e. max intensity), egress, and egress rate are quantitatively determined while simultaneously displaying qualitative visual results.…”

Pancreaticoduodenectomy following surgery for esophageal cancer with gastric tube reconstruction: a case report and literature review

“…ICG is usually used to directly measure the actual functional state of the liver [17]. Recently, ICG has been widely used to capture changes in intestinal ischemia [18, 19]. Ishizuka et al reported that using ICG in patients with nonocclusive mesenteric ischemia could facilitate proper removal of the ischemic intestine [20].…”