Recruitment of sublingual microcirculation using handheld incident dark field imaging as a routine measurement tool during the postoperative de-escalation phase—a pilot study in post ICU cardiac surgery patients

Introduction: Intestinal blood flow is often named as a key factor in the pathophysiology of anastomotic leakage. The distribution between mucosal and serosal microperfusion during surgery remains to be elucidated. Objective: The aim of this study was to assess if the mucosal microcirculation of the intestine is more vulnerable to a surgical hit than the serosal microcirculation during surgery. Methods: In an observational cohort study (n = 9 patients), the microcirculation of the bowel serosa and mucosa was visualized with incident dark-field imaging during surgery. At the planned anastomosis, the following microcirculatory parameters were determined: microvascular flow index (MFI), percentage of perfused vessels (PPV), perfused vessel density (PVD), and total vessel density (TVD). Data are presented as median (interquartile range [IQR]). Results: Perfusion parameters and vessel density were significantly higher for the mucosa than the serosal microcirculation at the planned site for anastomosis or stoma. Mucosal MFI was 3.00 (IQR 3.00–3.00) compared to a serosal MFI of 2.75 (IQR 2.21–2.94), p = 0.03. The PPV was 99% (IQR 98–100) versus 92% (IQR 66–94), p = 0.01. The TVD was 16.77 mm/mm2 (IQR 13.04–18.01) versus 10.42 mm/mm2 (IQR 9.36–11.81), p = 0.01, and the PVD was 15.44 mm/mm2 (IQR 13.04–17.78) versus 9.02 mm/mm2 (IQR 6.43–9.43), p = 0.01. Conclusions: The mucosal microcirculation was preserved, while lower perfusion of the serosa was found at the planned anastomosis or stoma during surgery. Further research is needed to link our observations to the clinically relevant endpoint of anastomotic leakage.

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Intraoperative Incident Dark Field Imaging of the Human Peritoneal Microcirculation

Journal of Vascular Research ◽

10.1159/000488392 ◽

2018 ◽

Vol 55 (3) ◽

pp. 136-143 ◽

Cited By ~ 3

Author(s):

Zühre Uz ◽

Arnoud W. Kastelein ◽

Dan M.J. Milstein ◽

Dan Liu ◽

Fadi Rassam ◽

...

Keyword(s):

Dark Field ◽

Dark Field Imaging ◽

Incident Dark Field Imaging ◽

Field Imaging

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Sidestream versus incident dark field imaging: How to compare two different technologies to study the microcirculation?

Journal of Clinical Monitoring and Computing ◽

10.1007/s10877-015-9740-5 ◽

2015 ◽

Vol 29 (5) ◽

pp. 539-540 ◽

Cited By ~ 5

Author(s):

Christian Lehmann ◽

Joel Sardinha ◽

Ahmed M. Mukhtar

Keyword(s):

Dark Field ◽

Dark Field Imaging ◽

Incident Dark Field Imaging ◽

Field Imaging

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Evaluation of microcirculation by Sidestream Dark Field imaging: Impact of hemodynamic status on the occurrence of pressure artifacts – A pilot study

Microvascular Research ◽

10.1016/j.mvr.2020.104025 ◽

2020 ◽

Vol 131 ◽

pp. 104025

Author(s):

Mathieu Magnin ◽

Élisa Foulon ◽

Thibaut Lurier ◽

Bernard Allaouchiche ◽

Jeanne-Marie Bonnet-Garin ◽

...

Keyword(s):

Pilot Study ◽

Dark Field ◽

Sidestream Dark Field ◽

Hemodynamic Status ◽

Dark Field Imaging ◽

Sidestream Dark Field Imaging ◽

Field Imaging

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Detection of a point defect in a silicon single crystal by high-resolution TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138701 ◽

1995 ◽

Vol 53 ◽

pp. 466-467

Author(s):

M. Awaji

Keyword(s):

High Resolution ◽

Single Crystal ◽

Point Defect ◽

Point Defects ◽

Noise Level ◽

Dark Field ◽

Silicon Single Crystal ◽

High Resolution Image ◽

Dark Field Imaging ◽

Field Imaging

It is necessary to improve the resolution, brightness and signal-to-noise ratio(s/n) for the detection and identification of point defects in crystals. In order to observe point defects, multi-beam dark-field imaging is one of the useful methods. Though this method can improve resolution and brightness compared with dark-field imaging by diffuse scattering, the problem of s/n still exists. In order to improve the exposure time due to the low intensity of the dark-field image and the low resolution, we discuss in this paper the bright-field high-resolution image and the corresponding subtracted image with reference to a changing noise level, and examine the possibility for in-situ observation, identification and detection of the movement of a point defect produced in the early stage of damage process by high energy electron bombardment.The high-resolution image contrast of a silicon single crystal in the [10] orientation containing a triple divacancy cluster is calculated using the Cowley-Moodie dynamical theory and for a changing gaussian noise level. This divacancy model was deduced from experimental results obtained by electron spin resonance. The calculation condition was for the lMeV Berkeley ARM operated at 800KeV.

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Correlation of image quality parameters with tube voltage in X-ray dark-field chest radiography: a phantom study

Scientific Reports ◽

10.1038/s41598-021-93716-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Andreas P. Sauter ◽

Jana Andrejewski ◽

Manuela Frank ◽

Konstantin Willer ◽

Julia Herzen ◽

...

Keyword(s):

Image Quality ◽

Imaging Modality ◽

Signal Strength ◽

Dark Field ◽

Tube Voltage ◽

X Ray ◽

Dose Area Product ◽

Dark Field Imaging ◽

Field Imaging

AbstractGrating-based X-ray dark-field imaging is a novel imaging modality with enormous technical progress during the last years. It enables the detection of microstructure impairment as in the healthy lung a strong dark-field signal is present due to the high number of air-tissue interfaces. Using the experience from setups for animal imaging, first studies with a human cadaver could be performed recently. Subsequently, the first dark-field scanner for in-vivo chest imaging of humans was developed. In the current study, the optimal tube voltage for dark-field radiography of the thorax in this setup was examined using an anthropomorphic chest phantom. Tube voltages of 50–125 kVp were used while maintaining a constant dose-area-product. The resulting dark-field and attenuation radiographs were evaluated in a reader study as well as objectively in terms of contrast-to-noise ratio and signal strength. We found that the optimum tube voltage for dark-field imaging is 70 kVp as here the most favorable combination of image quality, signal strength, and sharpness is present. At this voltage, a high image quality was perceived in the reader study also for attenuation radiographs, which should be sufficient for routine imaging. The results of this study are fundamental for upcoming patient studies with living humans.

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