Comparison of the ViOptix Intra.Ox Near Infrared Tissue Spectrometer and Indocyanine Green Angiography in a Porcine Bowel Model

2020 ◽  
Vol 36 (06) ◽  
pp. 426-431
Author(s):  
Nima Khavanin ◽  
Hamda Almaazmi ◽  
Halley Darrach ◽  
Franca Kraenzlin ◽  
Bashar Safar ◽  
...  
Keyword(s):  
Indocyanine Green ◽  
Indocyanine Green Angiography ◽  
Near Infrared ◽  
Tissue Oxygenation ◽  
Imaging System ◽  
Correlation Coefficients ◽  
Tissue Perfusion ◽  
Infrared Spectrometer ◽  
Perfusion Assessment ◽  
Near Infrared Spectrometer

Abstract Background This study aims to directly compare measurements of tissue oxygenation obtained using the Intra.Ox (Vioptix Inc., Fremont, CA) near infrared spectrometer with the perfusion assessment of the indocyanine green (ICG)-based SPY Elite imaging system (Stryker Co., Kalamazoo, MI) in a porcine bowel model. Methods Two live minipigs underwent laparotomy and isolation of a 30-cm segment of a large bowel. Standardized oximetry measurements were taken along the segment of bowel immediately before, after, and serially for 30 minutes following transection. A 0.5 mg/kg dose of ICG was then injected intravenously and the SPY Elite system was used to visualize and quantify tissue perfusion. Pearson's correlation coefficients were calculated using the outcomes. Results Transected and ligated bowel yielded mean Intra.Ox measurements of 61% oxygenation at the proximal base of the limb and 27.8% at the distal edges. Analysis of the relative ICG fluorescence using the SPY Elite's proprietary software yielded perfusion estimates of 64.8% proximally and 6.8% distally. Intra.Ox and SPY Elite measurements demonstrate a Pearson product–moment correlation of 0.929. Repeat measurements at 15-mm intervals along the tissue yielded decreasing Intra.Ox measurements along the length of the flap that correlate to SPY Elite measurements (r = 0.645). Conclusion Both the Intra.Ox and the SPY detected clinically relevant changes in bowel oxygenation following transection and ligation. The use of intravenous ICG dye did not appear to affect measurements of tissue oxygenation obtained using the Intra.Ox.

scholarly journals The Improvement on the Performance of DMD Hadamard Transform Near-Infrared Spectrometer by Double Filter Strategy and a New Hadamard Mask

Micromachines ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 149 ◽  
Author(s):  
Zifeng Lu ◽  
Jinghang Zhang ◽  
Hua Liu ◽  
Jialin Xu ◽  
Jinhuan Li
Keyword(s):  
Near Infrared ◽  
Signal To Noise Ratio ◽  
Nonuniform Distribution ◽  
Stray Light ◽  
Spectral Energy ◽  
Hadamard Transform ◽  
Digital Micromirror Device ◽  
Infrared Spectrometer ◽  
Near Infrared Spectrometer ◽  
The Impact

In the Hadamard transform (HT) near-infrared (NIR) spectrometer, there are defects that can create a nonuniform distribution of spectral energy, significantly influencing the absorbance of the whole spectrum, generating stray light, and making the signal-to-noise ratio (SNR) of the spectrum inconsistent. To address this issue and improve the performance of the digital micromirror device (DMD) Hadamard transform near-infrared spectrometer, a split waveband scan mode is proposed to mitigate the impact of the stray light, and a new Hadamard mask of variable-width stripes is put forward to improve the SNR of the spectrometer. The results of the simulations and experiments indicate that by the new scan mode and Hadamard mask, the influence of stray light is restrained and reduced. In addition, the SNR of the spectrometer also is increased.

Investigating the total antioxidant capacity of gluten-free grains with miniaturized near-infrared spectrometer

NIR news ◽  
2019 ◽  
Vol 30 (5-6) ◽  
pp. 35-38
Author(s):  
Verena Wiedemair ◽  
Christian Wolfgang Huck
Keyword(s):  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
High Performance ◽  
Near Infrared ◽  
Least Squares Regression ◽  
Test Set ◽  
Total Antioxidant ◽  
Infrared Spectrometer ◽  
Near Infrared Spectrometer ◽  
Infrared Instruments

The use of ever smaller near-infrared instruments is becoming more and more prevalent, since they are cheaper, more versatile and often advertised as high-performance spectrometer. The last claim is rarely verified by independent researchers, which is why the presented work evaluates the performance of three hand-held spectrometers in comparison to a benchtop instrument. Seventy-seven samples comprising buckwheat, millet and oat were investigated for their total antioxidant capacity using Folin–Ciocalteu and near-infrared spectroscopy. Partial least squares regression models were established using cross- and test set validation. Results showed that all instruments were able to predict total antioxidant capacity to some extent. The coefficients of determinations ranged from 0.823 to 0.951 for cross-validated and from 0.849 to 0.952 for test set validated models. Errors for cross-validated models ranged from 1.11 to 2.08 mgGAE/g and for test set validated models from 1.02 to 1.86 mgGAE/g.

Near-infrared fluorescence imaging with indocyanine green for quantification of changes in tissue perfusion following revascularization

Vascular ◽  
2021 ◽  
pp. 170853812110328
Author(s):  
Pim Van den Hoven ◽  
Floris S Weller ◽  
Merel Van De Bent ◽  
Lauren N Goncalves ◽  
Melissa Ruig ◽  
...  
Keyword(s):  
Indocyanine Green ◽  
Fluorescence Imaging ◽  
Fluorescence Intensity ◽  
Near Infrared ◽  
Tissue Perfusion ◽  
Control Group ◽  
Maximum Slope ◽  
Nir Fluorescence ◽  
Significant Difference ◽  
Revascularization Procedures

Objectives Current diagnostic modalities for patients with peripheral artery disease (PAD) mainly focus on the macrovascular level. For assessment of tissue perfusion, near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) seems promising. In this prospective cohort study, ICG NIR fluorescence imaging was performed pre- and post-revascularization to assess changes in foot perfusion. Methods ICG NIR fluorescence imaging was performed in 36 patients with PAD pre- and post-intervention. After intravenous bolus injection of 0.1 mg/kg ICG, the camera registered the NIR fluorescence intensity over time on the dorsum of the feet for 15 min using the Quest Spectrum Platform®. Time-intensity curves were plotted for three regions of interest (ROI): (1) the dorsum of the foot, (2) the forefoot, and (3) the hallux. Time-intensity curves were normalized for maximum fluorescence intensity. Extracted parameters were the maximum slope, area under the curve (AUC) for the ingress, and the AUC for the egress. The non-treated contralateral leg was used as a control group. Results Successful revascularization was performed in 32 patients. There was a significant increase for the maximum slope and AUC egress in all three ROIs. The most significant difference was seen for the maximum slope in ROI 3 (3.7%/s to 6.6%/s, p < 0.001). In the control group, no significant differences were seen for the maximum slope and AUC egress in all ROIs. Conclusions This study shows the potential of ICG NIR fluorescence imaging in assessing the effect of revascularization procedures on foot perfusion. Future studies should focus on the use of this technique in predicting favorable outcome of revascularization procedures.

A Compact Near-Infrared Spectrometer based on an FR4 Electromagnetic Scanning Grating

2021 ◽  
Author(s):  
Russell Farrugia ◽  
Barnaby Portelli ◽  
Ivan Grech ◽  
Joseph Micallef ◽  
Owen Casha ◽  
...  
Keyword(s):  
Near Infrared ◽  
Electromagnetic Scanning ◽  
Infrared Spectrometer ◽  
Near Infrared Spectrometer
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