Visible hyperspectral imaging evaluating the cutaneous response to ultraviolet radiation

Ilias, Michail; Häggblad, Erik; Anderson, Chris; Salerud, E. Göran

doi:10.1117/12.698165

Cited by 8 publications

(9 citation statements)

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“…Spectral imaging techniques that monitor endogenous molecules by measuring wavelengthdependent changes in diffusely-reflected light have been reported in the literature for the visualisation and quantification of the content of various biological tissues, as well as detection of abnormal tissue [5]. This includes melanin, water [6] and haemoglobin [7][8][9]. Internal organs are dominated by the signal from haemoglobin in the blood, whose absorption spectrum changes shape depending on whether or not oxygen is attached.…”

Section: Introductionmentioning

confidence: 99%

Intraoperative measurement of bowel oxygen saturation using a multispectral imaging laparoscope

Clancy

Arya

Stoyanov

et al. 2015

Biomed. Opt. Express

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Intraoperative monitoring of tissue oxygen saturation (StO2 ) has potentially important applications in procedures such as organ transplantation or colorectal surgery, where successful reperfusion affects the viability and integrity of repaired tissues. In this paper a liquid crystal tuneable filter-based multispectral imaging (MSI) laparoscope is described. Motion-induced image misalignments are reduced, using feature-based registration, before regression of the tissue reflectance spectra to calculate relative quantities of oxy- and deoxyhaemoglobin. The laparoscope was validated in vivo, during porcine abdominal surgery, by making parallel MSI and blood gas measurements of the small bowel vasculature. Ischaemic conditions were induced by local occlusion of the mesenteric arcade and monitored using the system. The MSI laparoscope was capable of measuring StO2 over a wide range (30-100%) with a temporal error of ± 7.5%. The imager showed sensitivity to spatial changes in StO2 during dynamic local occlusions, as well as tracking the recovery of tissues post-occlusion.

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Section: Introductionmentioning

confidence: 99%

Intraoperative measurement of bowel oxygen saturation using a multispectral imaging laparoscope

Clancy

Arya

Stoyanov

et al. 2015

Biomed. Opt. Express

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“…a OH , a DOH and a Mel represent the relative chromophore concentration values; a Offset is the difference between the predicted and measured spectra. The predicted OD spectrum at each image pixel was compared to the measured OD spectrum by solving the nonlinear least-squares problem using the Trust-Region algorithm [10], with subsequent extraction of the corresponding relative concentrations of the skin chromophores [2]. The reference absorption spectra of the three chromophores were taken from the literature data [11,12].…”

Section: Data Acquisition and Processingmentioning

confidence: 99%

“…oxy-/deoxy-haemoglobin and melanin [1,2]. Such mapping ensures reliable non-invasive evaluation of skin condition [3][4][5].…”

Section: Introductionmentioning

confidence: 99%

“…Such mapping ensures reliable non-invasive evaluation of skin condition [3][4][5]. The least-squares regression analysis of a broad visible-NIR spectral range (450-720 nm [2], 460-820 nm [6]) was successfully used to estimate the chromophore content in skin. Drawback of this technique is very time-consuming (proportional to the quantity of spectral information) data acquisition and processing; narrowing of the working spectral range cer- …”

Section: Introductionmentioning

confidence: 99%

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2‐D mapping of skin chromophores in the spectral range 500 – 700 nm

Jakovels

Spīgulis

2010

Journal of Biophotonics

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The multi-spectral imaging technique has been used for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel and constructing 2-D maps of the relative concentrations of oxy-/deoxy-haemoglobin and melanin. Instead of using a broad visible-NIR spectral range, this study focuses on narrowed spectral band 500-700 nm, speeding-up the signal processing procedure. Regression analysis confirmed that superposition of three Gaussians is optimal analytic approximation for the oxy-haemoglobin absorption tabular spectrum in this spectral band, while superposition of two Gaussians fits well for deoxy-haemoglobin absorption and exponential function - for melanin absorption. The proposed approach was clinically tested for three types of in-vivo skin provocations: ultraviolet irradiance, chemical reaction with vinegar essence and finger arterial occlusion. Spectral range 500-700 nm provided better sensitivity to oxy-haemoglobin changes and higher response stability to melanin than two reduced ranges 500-600 nm and 530-620 nm.

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“…Spectral imaging techniques have been reported for the quantification of a number of chromophores such as melanin, water 2 and haemoglobin [3][4][5] . The signal from the latter is dominant in the internal anatomy and is exploited by commercially available narrowband imaging instruments in flexible endoscopy [6][7][8] .…”

Section: Optical Imaging Of Perfusion and Ischaemiamentioning

confidence: 99%

Multispectral imaging of organ viability during uterine transplantation surgery

et al. 2014

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Uterine transplantation surgery has been proposed as a treatment for permanent absolute uterine factor infertility (AUFI) in the case of loss of the uterus. Due to the complexity of the vasculature correct reanastomosis of the blood supply during transplantation surgery is a crucial step to ensure reperfusion and viability of the organ.While techniques such as fluorescent dye imaging have been proposed to visualise perfusion there is no gold standard for intraoperative visualisation of tissue oxygenation. In this paper results from a liquid crystal tuneable filter (LCTF)-based multispectral imaging (MSI) laparoscope are described. The system was used to monitor uterine oxygen saturation (SaO 2 ) before and after transplantation. Results from surgeries on two animal models (rabbits and sheep) are presented.A feature-based registration algorithm was used to correct for misalignment induced by breathing or peristalsis in the tissues of interest prior to analysis. An absorption spectrum was calculated at each spatial pixel location using reflectance data from a reference standard, and the relative contributions from oxy-and deoxyhaemoglobin were calculated using a least squares regression algorithm with non-negativity constraints.Results acquired during animal surgeries show that cornual oxygenation changes are consistent with those observed in point measurements taken using a pulse oximeter, showing reduced SaO 2 following reanastomosis. Values obtained using the MSI laparoscope were lower than those taken with the pulse oximeter, which may be due to the latter's use of the pulsatile arterial blood signal. Future work incorporating immunological test results will help to correlate SaO 2 levels with surgical outcomes.

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Visible hyperspectral imaging evaluating the cutaneous response to ultraviolet radiation

Cited by 8 publications

References 0 publications

Intraoperative measurement of bowel oxygen saturation using a multispectral imaging laparoscope

Intraoperative measurement of bowel oxygen saturation using a multispectral imaging laparoscope

2‐D mapping of skin chromophores in the spectral range 500 – 700 nm

Multispectral imaging of organ viability during uterine transplantation surgery

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