Real-time optical tracking of a diffuse reflectance spectroscopy probe for gastrointestinal tissue analysis

2021 ◽  
Author(s):  
Ioannis Gkouzionis ◽  
Fernando Avila-Rencoret ◽  
Jamie Murphy ◽  
Christopher Peters ◽  
Daniel Elson
Keyword(s):  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
Optical Tracking ◽  
Tissue Analysis ◽  
Gastrointestinal Tissue

scholarly journals O-OGC03 Real-time tracking and classification of tumour and non-tumour tissue in upper gastrointestinal cancer specimens using diffuse reflectance spectroscopy

2021 ◽  
Vol 108 (Supplement_9) ◽  
Author(s):  
Scarlet Nazarian ◽  
Ioannis Gkouzionis ◽  
Michal Kawka ◽  
Nisha Patel ◽  
Ara Darzi ◽  
...  
Keyword(s):  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Tracking System ◽  
Reflectance Spectroscopy ◽  
Tumour Tissue ◽  
Acquisition Time ◽  
Margin Assessment ◽  
Real Time Tracking

Abstract Background Diffuse reflectance spectroscopy (DRS) is a technique that allows discrimination of normal and abnormal tissue based on spectral data. It is a promising technique for cancer margin assessment. However, application in a clinical setting is limited by the inability of DRS to mark the tissue that has been scanned and its lack of continuous real-time spectral measurements. This aim of this study was to develop a real-time tracking system to enable localisation of the tip of a handheld DRS probe to aid classification of tumour and non-tumour tissue. Methods A coloured marker was attached to the DRS fibre probe and was detected using colour segmentation. A Kalman filter was used to estimate the probe’s tip position during scanning of the tissue specimen. In this way, the system was robust to partial occlusion allowing real-time detection and tracking. Supervised classification algorithms were used for the discrimination between tumour and non-tumour tissue, and evaluated in terms of overall accuracy, sensitivity, specificity, and the area under the curve (AUC). A live augmented view with all the tracked and classified optical biopsy sites were presented, providing visual feedback to the surgeons. Results A green coloured marker was successfully used to track the DRS probe. The measured root mean square error of probe tip tracking was 1.18±0.58mm and 1.05±0.28mm for the X and Y directions, respectively, whilst the maximum measured error was 1.76mm. Overall, 47 distinct sets of tumour and non-tumour tissue data were recorded through real-time tracking of ex vivo oesophageal and gastric tissue. The overall diagnostic accuracy of the system to classify tumour and non-tumour tissue in real-time was 94% for stomach and 96% for the oesophagus. Conclusions We have been able to successfully develop a real-time tracking system for a DRS probe when used on stomach and oesophageal tissue for tumour detection, and the accuracy derived demonstrates the strength and clinical value of the technique. The method allows real-time tracking and classification with short data acquisition time to aid margin assessment in cancer resection surgery.

SP7.1.6 Using Diffuse Reflectance Spectroscopy (DRS) to Identify Tumour and Non-tumour Tissue in Upper Gastrointestinal Specimens

2021 ◽  
Vol 108 (Supplement_7) ◽  
Author(s):  
Scarlet Nazarian ◽  
Ioannis Gkouzionis ◽  
Arun Anandakumar ◽  
Nisha Patel ◽  
Daniel Elson ◽  
...  
Keyword(s):  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
Tumour Tissue ◽  
Surrounding Tissue ◽  
Upper Gi ◽  
Gi Cancer ◽  
Upper Gi Cancer ◽  
Upper Gastrointestinal

Abstract Aim Cancers of the upper gastrointestinal (GI) tract remain a major contributor to the global cancer risk. Surgery aims to completely resect tumour with clear margins, whilst preserving as much surrounding tissue. Diffuse reflectance spectroscopy (DRS) is a novel technique that presents a promising advancement in cancer diagnosis. We have developed a novel DRS system with tracking capability. Our aim is to classify tumour and non-tumour GI tissue in real-time using this device to aid intra-operative analysis of resection margins. Method An ex-vivo study was undertaken in which data was collected from consecutive patients undergoing upper GI cancer resection surgery between August 2020- January 2021. A hand-held DRS probe and tracking system was used on normal and cancerous tissue to obtain spectral information. After acquisition of all spectra, a classification system using histopathology results was created. A user interface was developed using Python 3.6 and Qt5. A support vector machine was used to classify the results. Results The data included 4974 normal spectra and 2108 tumour spectra. The overall accuracy of the DRS probe in differentiating normal versus tumour tissue was 88.08% for the stomach (sensitivity 84.8%, specificity 89.3%), and 91.42% for the oesophagus (sensitivity 76.3%, specificity 98.9%). Conclusion We have developed a successful DRS system with tracking capability, able to process thousands of spectra in a small timeframe, which can be used in real-time to distinguish tumour and non-tumour tissue. This can be used for intra-operative decision-making during upper GI cancer surgery to help select the best resection plane.

scholarly journals Raman Spectroscopy Differentiates Each Tissue from the Skin to the Spinal Cord

2016 ◽  
Vol 125 (4) ◽  
pp. 793-804 ◽  
Author(s):  
T. Anthony Anderson ◽  
Jeon Woong Kang ◽  
Tatyana Gubin ◽  
Ramachandra R. Dasari ◽  
Peter T. C. So
Keyword(s):  
Raman Spectroscopy ◽  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Ex Vivo ◽  
Needle Insertion ◽  
Reflectance Spectroscopy ◽  
Epidural Needle ◽  
Needle Placement ◽  
Porcine Tissue

Abstract Background Neuraxial anesthesia and epidural steroid injection techniques require precise anatomical targeting to ensure successful and safe analgesia. Previous studies suggest that only some of the tissues encountered during these procedures can be identified by spectroscopic methods, and no previous study has investigated the use of Raman, diffuse reflectance, and fluorescence spectroscopies. The authors hypothesized that real-time needle-tip spectroscopy may aid epidural needle placement and tested the ability of spectroscopy to distinguish each of the tissues in the path of neuraxial needles. Methods For comparison of detection methods, the spectra of individual, dissected ex vivo paravertebral and neuraxial porcine tissues were collected using Raman spectroscopy (RS), diffuse reflectance spectroscopy, and fluorescence spectroscopy. Real-time spectral guidance was tested using a 2-mm inner-diameter fiber-optic probe-in-needle device. Raman spectra were collected during the needle’s passage through intact paravertebral and neuraxial porcine tissue and analyzed afterward. The RS tissue signatures were verified as mapping to individual tissue layers using histochemical staining and widefield microscopy. Results RS revealed a unique spectrum for all ex vivo paravertebral and neuraxial tissue layers; diffuse reflectance spectroscopy and fluorescence spectroscopy were not distinct for all tissues. Moreover, when accounting for the expected order of tissues, real-time Raman spectra recorded during needle insertion also permitted identification of each paravertebral and neuraxial porcine tissue. Conclusions This study demonstrates that RS can distinguish the tissues encountered during epidural needle insertion. This technology may prove useful during needle placement by providing evidence of its anatomical localization.

Precision of Non-invasive Temperature Measurement by Diffuse Reflectance Spectroscopy

1995 ◽  
Vol 406 ◽  
Author(s):  
Zhongze Wang ◽  
Siu L. Kwan ◽  
T. P. Pearsall ◽  
James Booth ◽  
Barrett T. Beard ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Temperature Measurement ◽  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
Optical Technique ◽  
Semiconductor Processing ◽  
Non Invasive ◽  
Gaas Substrates

AbstractWe demonstrate the use of diffuse reflectance spectroscopy as a non-invasive probe for measurement of temperature in real time on Si and GaAs substrates during semiconductor processing. Our results show that the standard deviation of the non-invasive optical technique is less than 0.7 °C for GaAs over the temperature range 50 °C < T< 600 °C with 5-second updates. These results support the notion that non-invasive optical temperature measurement can be used in semiconductor processing with a precision exceeding that of a thermocouple.

scholarly journals Towards the use of diffuse reflectance spectroscopy for real-time in vivo detection of breast cancer during surgery

2018 ◽  
Vol 16 (1) ◽  
Author(s):  
Lisanne L. de Boer ◽  
Torre M. Bydlon ◽  
Frederieke van Duijnhoven ◽  
Marie-Jeanne T. F. D. Vranken Peeters ◽  
Claudette E. Loo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Real Time ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
In Vivo Detection
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