Race‐specific differences in the phase coherence between blood flow and oxygenation: A simultaneous NIRS, white light spectroscopy and LDF study

Abstract INTRODUCTION Vascular structures are intraoperatively visualized through the eye-piece of a surgical microscope. The blood flow within the blood vessels can be demonstrated via indocyanine green (ICG) fluorescence. In this study we wanted to find out whether the development of a novel fluorescent surgical microscope, overlapping a multispectral fluorescent image on a white light image, is superior, equal or inferior, compared to the previous models. Moreover, it shall be proved, whether multispectral fluorescence enhances surgeon's orientation through the precise and clearer visualization of blood vessels and the blood flow. METHODS A total of 8 porcine animal models were used. After fixation of the animal's head the parietal cortex and the cortical blood vessels were exposed. A digital imaging of the arterial perfusion, capillary transition and venous drainage after intravenous injection of ICG (5 ml; 5 mg/ml) was then performed. The blood flow was artificially blocked by a surgical clip. After repetitive intravenous injection of ICG and visualisation with multispectral view, the surgical clip was removed and the reperfusion of the brain tissue was visualized with the real time ICG perfusion. RESULTS >The visualization of the anatomical structures of the surgical field under white light as well as the image overlapping were easily performed. The occlusion of blood vessels with surgical clips demonstrate a blockage of the ICG perfusion on the multispectral fluorescent image. The ICG perfusion was again demonstrated after removing the surgical clip and reperfusion of the blood vessel. CONCLUSION Multispectral fluorescence was shown to be superior to the classic ICG fluorescence. With the development of a novel multispectral surgical microscope, which overlaps a fluorescent image on a white light image, the data delivered to the surgeon are enhanced, compared to the previous models. Moreover, the surgeons's orientation is improved thanks to the clear visualization of blood vessels and the blood flow.

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Phase Coherence of Finger Skin Blood Flow Oscillations Induced by Controlled Breathing in Humans

Understanding Complex Systems - Physics of Biological Oscillators ◽

10.1007/978-3-030-59805-1_18 ◽

2021 ◽

pp. 281-289

Author(s):

Arina V. Tankanag ◽

Gennady V. Krasnikov ◽

Nikolai K. Chemeris

Keyword(s):

Blood Flow ◽

Skin Blood Flow ◽

Phase Coherence ◽

Blood Flow Oscillations ◽

Flow Oscillations ◽

Controlled Breathing ◽

Finger Skin ◽

Skin Blood Flow Oscillations

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Wavelet Phase Coherence Analysis: Application to Skin Temperature and Blood Flow

Cardiovascular Engineering An International Journal ◽

10.1023/b:care.0000025126.63253.43 ◽

2004 ◽

Vol 4 (1) ◽

pp. 89-93 ◽

Cited By ~ 86

Author(s):

Andriy Bandrivskyy ◽

Alan Bernjak ◽

Peter McClintock ◽

Aneta Stefanovska

Keyword(s):

Blood Flow ◽

Skin Temperature ◽

Phase Coherence ◽

Coherence Analysis ◽

Analysis Application

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Indocyanine green videoangiography for recipient vessel stratification in superficial temporal artery–middle cerebral artery bypass surgery

Journal of Neurosurgery ◽

10.3171/2020.5.jns20642 ◽

2020 ◽

pp. 1-9

Author(s):

Johannes Goldberg ◽

Peter Vajkoczy ◽

Nils Hecht

Keyword(s):

Blood Flow ◽

White Light ◽

Bypass Surgery ◽

Flow Direction ◽

Superficial Temporal Artery ◽

Flow Patterns ◽

Low Flow ◽

Indocyanine Green Videoangiography ◽

Recipient Vessel ◽

Potential Recipient

OBJECTIVEIn superficial temporal artery–middle cerebral artery (STA-MCA) bypass surgery, recipient vessel properties are likely one of the main reasons for bypass failure. In daily practice, most surgeons select the recipient with the largest diameter. However, selection of the ideal recipient remains debatable because there are no objective selection criteria if multiple potential recipients exist. Here, the authors assessed the benefit of using indocyanine green videoangiography (ICG-VA) to optimize recipient vessel selection in patients undergoing STA-MCA bypass surgery for hemodynamic compromise.METHODSAll patients who had undergone STA-MCA bypass procedures with pre- and postanastomosis ICG-VA between 2010 and 2019 were eligible for inclusion in this study. The primary bypass surgeon was blinded to the preanastomosis ICG-VA. Preanastomosis white-light and ICG-VA images were compared to determine the identifiability of potential recipient vessels and pathological flow patterns. After completion of the anastomosis, a second (postanastomosis) ICG-VA image was used to analyze the flow increase within the chosen recipient based on the vessel diameter, initial recipient blood flow, initial sequence of appearance on ICG-VA, initial blood flow direction within the recipient, and orientation of the bypass graft. ICG-VA, FLOW 800, and intraoperative white-light images, as well as demographic, clinical, and radiographic patient data, were retrospectively analyzed by a clinician who was not directly involved in the patients’ care.RESULTSSixty patients underwent 65 STA-MCA bypass procedures with pre- and postanastomosis ICG-VA. The ICG-VA permitted identification of a significantly higher number of potential recipient vessels (median 4, range 1–9) than the white-light images (median 2, range 1–5; p < 0.001), with detection of pathological flow patterns in 20% of all procedures. No association was found between the diameter and blood flow within potential recipients (Spearman r = 0.07, p = 0.69). After bypass grafting, the highest flow increase was noted in recipients with an initially low flow (p < 0.01), a late appearance (p < 0.01), and an initially retrograde flow direction (p = 0.02). Interestingly, flow increase was not significantly influenced by the recipient diameter (p = 0.09) or graft orientation (p = 0.44).CONCLUSIONSICG-VA facilitates identification of potential recipient vessels and detection of pathological flow patterns. Recipients with an initially low flow, a late appearance, and a retrograde flow seem to bear the highest potential for flow increase, possibly due to a higher hemodynamic need for revascularization.

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The Concept of White Light Cavities Using Atomic Phase Coherence

Physica Scripta ◽

10.1238/physica.topical.118a00085 ◽

2005 ◽

pp. 85 ◽

Cited By ~ 31

Author(s):

R.-H. Rinkleff ◽

A. Wicht

Keyword(s):

White Light ◽

Phase Coherence ◽

Atomic Phase

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Real-Time Overlapping of Indocyanine Green—Video Angiography With White Light Imaging for Vascular Neurosurgery: Technique, Implementation, and Clinical Experience

Operative Neurosurgery ◽

10.1093/ons/opaa050 ◽

2020 ◽

Vol 19 (4) ◽

pp. 453-460 ◽

Cited By ~ 1

Author(s):

Dimitrios Athanasopoulos ◽

Axel Heimann ◽

Makoto Nakamura ◽

Irini Kakaletri ◽

Oliver Kempski ◽

...

Keyword(s):

Blood Flow ◽

Indocyanine Green ◽

Real Time ◽

White Light ◽

Multispectral Imaging ◽

Tissue Perfusion ◽

Indocyanine Green Videoangiography ◽

Black And White ◽

Surgical Clip ◽

Vascular Neurosurgery

Abstract BACKGROUND Fluorescent-guided techniques in vascular neurosurgery can be demonstrated via black and white indocyanine green videoangiography (ICG-VA). Multispectral imaging (MFL) is a new method, which overlaps fluorescence with the white light and provides a fluorescent white light augmented reality image to the surgeon. OBJECTIVE To investigate (a) whether MFL can enhance the visualization of the blood-flow with simultaneous visualization of the anatomic structures and (b) if MFL can ergonomically improve the microvascular surgical treatment compared to ICG-VA. METHODS A digital imaging of the blood flow after intravenous injection of ICG on 7 pigs was performed in real time under white light, standard fluorescence, and MFL. The blood flow was interrupted with a surgical clip, demonstrating the blockage of the blood flow. We prospectively included 30 patients with vascular deformities. The vasculature was visualized on the microscope's monitor and through the microscope's eyepiece. RESULTS In the animal experiment, the visualization of the anatomy and the blood flow under MFL produced high resolution images. The occlusion of blood vessels demonstrated sufficiently the blockage of tissue perfusion and its reperfusion after clip removal. During all 30 surgical cases, the MFL technique and the direct delivery of the pseudo-colored image through the eyepiece allowed for enhanced anatomic and dynamic data. CONCLUSION MFL was shown to be superior to the classic ICG-VA, delivering enhanced data and notably improving the workflow due to the simultaneous and precise white light visualization of the blood flow and the surrounding anatomic structures.

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Wavelet phase coherence analysis of the skin blood flow oscillations in human

Microvascular Research ◽

10.1016/j.mvr.2014.07.003 ◽

2014 ◽

Vol 95 ◽

pp. 53-59 ◽

Cited By ~ 32

Author(s):

Arina V. Tankanag ◽

Andrey A. Grinevich ◽

Tatiana V. Kirilina ◽

Gennady V. Krasnikov ◽

Galina M. Piskunova ◽

...

Keyword(s):

Blood Flow ◽

Skin Blood Flow ◽

Phase Coherence ◽

Coherence Analysis ◽

Blood Flow Oscillations ◽

Flow Oscillations ◽

Skin Blood Flow Oscillations

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COHERENCE BETWEEN FLUCTUATIONS IN BLOOD FLOW AND OXYGEN SATURATION

Fluctuation and Noise Letters ◽

10.1142/s0219477512400135 ◽

2012 ◽

Vol 11 (01) ◽

pp. 1240013 ◽

Cited By ~ 41

Author(s):

ALAN BERNJAK ◽

ANETA STEFANOVSKA ◽

PETER V. E. McCLINTOCK ◽

P. JANE OWEN-LYNCH ◽

PETER B. M. CLARKSON

Keyword(s):

Blood Flow ◽

Oxygen Saturation ◽

Skin Blood Flow ◽

Healthy Subjects ◽

Phase Coherence ◽

Blood Oxygenation ◽

Microvascular Blood Flow ◽

Cardiac Frequency ◽

Causal Connections ◽

Insight Into

We have determined the wavelet phase coherence between simultaneously recorded microvascular blood flow and oxygen saturation signals from 88 healthy subjects, thus enabling us to study their common fluctuations. Measurements were taken for 30 min from the arm and leg, at two depths. In the skin, blood flow and oxygen saturation were found to be coherent both at the cardiac frequency and below 0.1 Hz down to about 0.01 Hz. Coherence in the arm extends to lower frequencies than that in the leg. From the deeper recordings, no coherence was found on either limb. The existence of coherence between skin blood flow and oxygen saturation demonstrates causal connections between them within certain frequency ranges. The method has yielded the first detailed insight into the dynamics of blood oxygenation.

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Integration of Indocyanine Green Videoangiography With Operative Microscope: Augmented Reality for Interactive Assessment of Vascular Structures and Blood Flow

Operative Neurosurgery ◽

10.1227/neu.0000000000000681 ◽

2015 ◽

Vol 11 (2) ◽

pp. 252-258 ◽

Cited By ~ 17

Author(s):

Nikolay L Martirosyan ◽

Jesse Skoch ◽

Jeffrey R Watson ◽

G Michael Lemole ◽

Marek Romanowski ◽

...

Keyword(s):

Blood Flow ◽

Indocyanine Green ◽

Real Time ◽

Femoral Artery ◽

White Light ◽

Near Infrared ◽

Field Of View ◽

Fluorescence Angiography ◽

Indocyanine Green Videoangiography ◽

Operative Microscope

Abstract BACKGROUND Preservation of adequate blood flow and exclusion of flow from lesions are key concepts of vascular neurosurgery. Indocyanine green (ICG) fluorescence videoangiography is now widely used for the intraoperative assessment of vessel patency. OBJECTIVE Here, we present a proof-of-concept investigation of fluorescence angiography with augmented microscopy enhancement: real-time overlay of fluorescence videoangiography within the white light field of view of conventional operative microscopy. METHODS The femoral artery was exposed in 7 anesthetized rats. The dissection microscope was augmented to integrate real-time electronically processed near-infrared filtered images with conventional white light images seen through the standard oculars. This was accomplished by using an integrated organic light-emitting diode display to yield superimposition of white light and processed near-infrared images. ICG solution was injected into the jugular vein, and fluorescent femoral artery flow was observed. RESULTS Fluorescence angiography with augmented microscopy enhancement was able to detect ICG fluorescence in a small artery of interest. Fluorescence appeared as a bright-green signal in the ocular overlaid with the anatomic image and limited to the anatomic borders of the femoral artery and its branches. Surrounding anatomic structures were clearly visualized. Observation of ICG within the vessel lumens permitted visualization of the blood flow. Recorded video loops could be reviewed in an offline mode for more detailed assessment of the vasculature. CONCLUSION The overlay of fluorescence videoangiography within the field of view of the white light operative microscope allows real-time assessment of the blood flow within vessels during simultaneous surgical manipulation. This technique could improve intraoperative decision making during complex neurovascular procedures.

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