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Wang R, Alvarez DA, Crouch BT, Pilani A, Lam C, Zhu C, Hughes P, Katz D, Haystead T, Ramanujam N. Understanding the sources of errors in ex vivo Hsp90 molecular imaging for rapid-on-site breast cancer diagnosis. BIOMEDICAL OPTICS EXPRESS 2021; 12:2299-2311. [PMID: 33996230 PMCID: PMC8086448 DOI: 10.1364/boe.418818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/26/2021] [Accepted: 03/16/2021] [Indexed: 05/12/2023]
Abstract
Overexpression of heat shock protein 90 (Hsp90) on the surface of breast cancer cells makes it an attractive molecular biomarker for breast cancer diagnosis. Before a ubiquitous diagnostic method can be established, an understanding of the systematic errors in Hsp90-based imaging is essential. In this study, we investigated three factors that may influence the sensitivity of ex vivo Hsp90 molecular imaging: time-dependent tissue viability, nonspecific diffusion of an Hsp90 specific probe (HS-27), and contact-based imaging. These three factors will be important considerations when designing any diagnostic imaging strategy based on fluorescence imaging of a molecular target on tissue samples.
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Affiliation(s)
- Roujia Wang
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Daniel A. Alvarez
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Brian T. Crouch
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Aditi Pilani
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Christopher Lam
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Caigang Zhu
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
- Currently at Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky, 40506, USA
| | - Philip Hughes
- Department of Pharmacology and Cancer Biology, School of Medicine, Duke University, Durham, North Carolina 27708, USA
| | - David Katz
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Timothy Haystead
- Department of Pharmacology and Cancer Biology, School of Medicine, Duke University, Durham, North Carolina 27708, USA
| | - Nirmala Ramanujam
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
- Department of Pharmacology and Cancer Biology, School of Medicine, Duke University, Durham, North Carolina 27708, USA
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2
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Spatially-Resolved Multiply-Excited Autofluorescence and Diffuse Reflectance Spectroscopy: SpectroLive Medical Device for Skin In Vivo Optical Biopsy. ELECTRONICS 2021. [DOI: 10.3390/electronics10030243] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This contribution presents the development of an optical spectroscopy device, called SpectroLive, that allows spatially-resolved multiply-excited autofluorescence and diffuse reflectance measurements. Besides describing the device, this study aims at presenting the metrological and safety regulation validations performed towards its aimed application to skin carcinoma in vivo diagnosis. This device is made of six light sources and four spectrometers for detection of the back-scattered intensity spectra collected through an optical probe (made of several optical fibers) featuring four source-to-detector separations (from 400 to 1000 µm). In order to be allowed by the French authorities to be evaluated in clinics, the SpectroLive device was successfully checked for electromagnetic compatibility and electrical and photobiological safety. In order to process spectra, spectral correction and metrological calibration were implemented in the post-processing software. Finally, we characterized the device’s sensitivity to autofluorescence detection: excitation light irradiance at the optical probe tip in contact with skin surface ranges from 2 to 11 W/m², depending on the light source. Such irradiances combined to sensitive detectors allow the device to acquire a full spectroscopic sequence within 6 s which is a short enough duration to be compatible with optical-guided surgery. All these results about sensitivity and safety make the SpectroLive device mature enough to be evaluated through a clinical trial that aims at evaluating its diagnostic accuracy for skin carcinoma diagnosis.
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Zhang XU, Faber DJ, Van Leeuwen TG, Sterenborg HJCM. Effect of probe pressure on skin tissue optical properties measurement using multi-diameter single fiber reflectance spectroscopy. JPHYS PHOTONICS 2020. [DOI: 10.1088/2515-7647/ab9071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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4
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Poh AH, Mahamd Adikan FR, Moghavvemi M, Syed Omar SF, Poh K, Mahyuddin MBH, Yan G, Azizah Ariffin MA, Harun SW. Precursors to non-invasive clinical dengue screening: Multivariate signature analysis of in-vivo diffuse skin reflectance spectroscopy on febrile patients in Malaysia. PLoS One 2020; 15:e0228923. [PMID: 32236132 PMCID: PMC7112162 DOI: 10.1371/journal.pone.0228923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 01/26/2020] [Indexed: 11/18/2022] Open
Abstract
Dengue diagnostics have come a long way. Attempts at breaking away from lab-oriented dengue detection, such as NS1 antigen, IgM or IgG antibodies detection have extensively received numerous coverage. As a result, rapid detection tests (RDTs) have started to gain inroads in medical practice. Rapid detection tests notwithstanding, analysis of blood serum is still a relatively complicated task. This includes the necessity of phlebotomy, centrifugation for blood serum, and other reagent-based tests. Therefore, a non-invasive method of dengue detection was considered. In this study, we present the utility of diffuse reflectance skin spectroscopy (bandwidth of 200-2500nm) on the forearm during the triaging period for dengue screening potential. This is performed with multivariate analysis of 240 triaged febrile/suspected dengue patients. The data is then scrutinized for its clinical validity to be included as either confirmed or probable dengue, or a control group. Based on discriminant analysis of several data normalization models, we can predict the patients' clinical dengue-positivity at ranges of accuracy between ~93-98% depending on mode of the data, with a probably optimal sensitivity and specificity to the clinical diagnosis of ~89% and ~100% respectively. From the outcomes of this study, we recommend further trials with cautious optimism. With these findings, it is hoped that the elusive non-invasive detection of tropical diseases may gain platform in the near future.
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Affiliation(s)
- Abdul Halim Poh
- Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Integrated Lightwave Research Group, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Research for Applied Electronics (CRAE), Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | - Faisal Rafiq Mahamd Adikan
- Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Integrated Lightwave Research Group, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
| | - Mahmoud Moghavvemi
- Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Research for Applied Electronics (CRAE), Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- University of Science and Culture, Tehran, Iran
| | - Sharifah Faridah Syed Omar
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Infectious Diseases and Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khadijah Poh
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohamad Badrol Hisyam Mahyuddin
- Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Photonics Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | - Grace Yan
- Integrated Lightwave Research Group, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Sulaiman Wadi Harun
- Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Photonics Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
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5
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A Dual-modality Smartphone Microendoscope for Quantifying the Physiological and Morphological Properties of Epithelial Tissues. Sci Rep 2019; 9:15713. [PMID: 31673087 PMCID: PMC6823483 DOI: 10.1038/s41598-019-52327-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 10/15/2019] [Indexed: 12/24/2022] Open
Abstract
We report a nonconcurrent dual-modality fiber-optic microendoscope (named SmartME) that integrates quantitative diffuse reflectance spectroscopy (DRS) and high-resolution fluorescence imaging (FLI) into a smartphone platform. The FLI module has a spatial resolution of ~3.5 µm, which allows the determination of the nuclear-cytoplasmic ratio (N/C) of epithelial tissues. The DRS has a spectral resolution of ~2 nm and can measure the total hemoglobin concentration (THC) and scattering properties of epithelial tissues with mean errors of 4.7% and 6.9%, respectively, which are comparable to the errors achieved with a benchtop spectrometer. Our preliminary in vivo studies from a single healthy human subject demonstrate that the SmartME can noninvasively quantify the tissue parameters of normal human oral mucosa tissues, including labial mucosa tissue, gingival tissue, and tongue dorsum tissue. The THCs of the three oral mucosa tissues are significantly different from each other (p ≤ 0.003). The reduced scattering coefficients of the gingival and labial tissues are significantly different from those of the tongue dorsum tissue (p < 0.001) but are not significantly different from each other. The N/Cs for all three tissue types are similar. The SmartME has great potential to be used as a portable, cost-effective, and globally connected tool to quantify the THC and scattering properties of tissues in vivo.
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Fluorescence spectroscopy in the visible range for the assessment of UVB radiation effects in hairless mice skin. Photodiagnosis Photodyn Ther 2017; 20:21-27. [DOI: 10.1016/j.pdpdt.2017.08.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/02/2017] [Accepted: 08/27/2017] [Indexed: 02/06/2023]
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7
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Popov AP, Bykov AV, Meglinski IV. Influence of probe pressure on diffuse reflectance spectra of human skin measured in vivo. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-4. [PMID: 29160043 DOI: 10.1117/1.jbo.22.11.110504] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 10/27/2017] [Indexed: 05/22/2023]
Abstract
Mechanical pressure superficially applied on the human skin surface by a fiber-optic probe influences the spatial distribution of blood within the cutaneous tissues. Upon gradual load of weight on the probe, a stepwise increase in the skin reflectance spectra is observed. The decrease in the load follows the similar inverse staircase-like tendency. The observed stepwise reflectance spectra changes are due to, respectively, sequential extrusion of blood from the topical cutaneous vascular beds and their filling afterward. The obtained results are confirmed by Monte Carlo modeling. This implies that pressure-induced influence during the human skin diffuse reflectance spectra measurements in vivo should be taken into consideration, in particular, in the rapidly developing area of wearable gadgets for real-time monitoring of various human body parameters.
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Affiliation(s)
- Alexey P Popov
- University of Oulu, Opto-Electronics and Measurement Techniques Research Unit, Faculty of Informatio, Finland
- ITMO University, International Institute of Photonics and Optoinformatics, St. Petersburg, Russia
| | - Alexander V Bykov
- University of Oulu, Opto-Electronics and Measurement Techniques Research Unit, Faculty of Informatio, Finland
- ITMO University, International Institute of Photonics and Optoinformatics, St. Petersburg, Russia
| | - Igor V Meglinski
- University of Oulu, Opto-Electronics and Measurement Techniques Research Unit, Faculty of Informatio, Finland
- ITMO University, International Institute of Photonics and Optoinformatics, St. Petersburg, Russia
- Irkutsk State University, Institute of Biology, Irkutsk, Russia
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8
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Bailey MJ, Verma N, Fradkin L, Lam S, MacAulay C, Poh C, Markey MK, Sokolov K. Detection of precancerous lesions in the oral cavity using oblique polarized reflectance spectroscopy: a clinical feasibility study. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:65002. [PMID: 28609512 PMCID: PMC5469421 DOI: 10.1117/1.jbo.22.6.065002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/18/2017] [Indexed: 05/20/2023]
Abstract
We developed a multifiber optical probe for oblique polarized reflectance spectroscopy (OPRS) in vivo and evaluated its performance in detection of dysplasia in the oral cavity. The probe design allows the implementation of a number of methods to enable depth resolved spectroscopic measurements including polarization gating, source–detector separation, and differential spectroscopy; this combination was evaluated in carrying out binary classification tasks between four major diagnostic categories: normal, benign, mild dysplasia (MD), and severe dysplasia (SD). Multifiber OPRS showed excellent performance in the discrimination of normal from benign, MD, SD, and MD plus SD yielding sensitivity/specificity values of 100%/93%, 96%/95%, 100%/98%, and 100%/100%, respectively. The classification of benign versus dysplastic lesions was more challenging with sensitivity and specificity values of 80%/93%, 71%/93%, and 74%/80% in discriminating benign from SD, MD, and SD plus MD categories, respectively; this challenge is most likely associated with a strong and highly variable scattering from a keratin layer that was found in these sites. Classification based on multiple fibers was significantly better than that based on any single detection pair for tasks dealing with benign versus dysplastic sites. This result indicates that the multifiber probe can perform better in the detection of dysplasia in keratinized tissues.
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Affiliation(s)
- Maria J. Bailey
- University of Texas M.D. Anderson Cancer Center, Department of Imaging Physics, Houston, Texas, United States
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Nishant Verma
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Leonid Fradkin
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Sylvia Lam
- British Columbia Cancer Agency, Integrative Oncology Department, Vancouver, British Columbia, Canada
| | - Calum MacAulay
- British Columbia Cancer Agency, Integrative Oncology Department, Vancouver, British Columbia, Canada
| | - Catherine Poh
- British Columbia Cancer Agency, Integrative Oncology Department, Vancouver, British Columbia, Canada
| | - Mia K. Markey
- University of Texas M.D. Anderson Cancer Center, Department of Imaging Physics, Houston, Texas, United States
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Konstantin Sokolov
- University of Texas M.D. Anderson Cancer Center, Department of Imaging Physics, Houston, Texas, United States
- University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
- Rice University, Department of Bioengineering, Houston, Texas, United States
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9
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Hariri Tabrizi S, Shakibaei AA. The Effect of Probe Pressure on In Vivo Single Fiber Reflectance Spectroscopy. J Lasers Med Sci 2017; 7:233-237. [PMID: 28491258 DOI: 10.15171/jlms.2016.41] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: Single fiber reflectance spectroscopy (SFRS) is a noninvasive procedure to quantitate tissue absorption and scattering properties. It can be used to diagnose different diseases such as malignancy and pre-cancerous conditions. The measurement is done with a fiber optic probe in contact with the tissue surface. Herein, the effect of probe pressure on the extracted parameters from human lip spectra was studied. Methods: Thirty-three normal subjects were examined with three exerted pressure levels on the right, middle and left parts of their lips. Results: The results showed variation of spectroscopic parameters with different pressure levels. However, the effect was seen between a very mild contact (pressure 1) and the other reasonably practical pressure levels normally used in the medical centers. Conclusion: SFRS can be used as a reliable diagnostic tool in clinics.
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Affiliation(s)
- Sanaz Hariri Tabrizi
- Department of Medical Radiation Engineering, Shahid Beheshti University, Tehran, Iran
| | - Ali Akbar Shakibaei
- Department of Physics, Eastern Mediterranean University, Famagusta, Via Mersin10, Turkey
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10
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Novikova T. Optical techniques for cervical neoplasia detection. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:1844-1862. [PMID: 29046833 PMCID: PMC5629403 DOI: 10.3762/bjnano.8.186] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 08/09/2017] [Indexed: 05/04/2023]
Abstract
This paper provides an overview of the current research in the field of optical techniques for cervical neoplasia detection and covers a wide range of the existing and emerging technologies. Using colposcopy, a visual inspection of the uterine cervix with a colposcope (a binocular microscope with 3- to 15-fold magnification), has proven to be an efficient approach for the detection of invasive cancer. Nevertheless, the development of a reliable and cost-effective technique for the identification of precancerous lesions, confined to the epithelium (cervical intraepithelial neoplasia) still remains a challenging problem. It is known that even at early stages the neoplastic transformations of cervical tissue induce complex changes and modify both structural and biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry, photoacoustic imaging), probe different tissue properties that may serve as optical biomarkers for diagnosis. Both the advantages and drawbacks of these techniques for the diagnosis of cervical precancerous lesions are discussed and compared.
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Affiliation(s)
- Tatiana Novikova
- LPICM, CNRS, Ecole polytechnique, University Paris Saclay, Palaiseau, France
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11
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Zhu C, Chen S, Chui CHK, Tan BK, Liu Q. Early detection and differentiation of venous and arterial occlusion in skin flaps using visible diffuse reflectance spectroscopy and autofluorescence spectroscopy. BIOMEDICAL OPTICS EXPRESS 2016; 7:570-80. [PMID: 26977363 PMCID: PMC4771472 DOI: 10.1364/boe.7.000570] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 01/11/2016] [Accepted: 01/13/2016] [Indexed: 05/22/2023]
Abstract
Our previous preclinical study demonstrated that both visible diffuse reflectance and autofluorescence spectroscopy, each of which yields a different set of physiological information, can predict skin flap viability with high accuracy in a MacFarlane rat dorsal skin flap model. In this report, we further evaluated our technique for the early detection and differentiation of venous occlusion and arterial occlusion in a rat groin flap model. We performed both diffuse reflectance and autofluorescence measurements on the skin flap model and statistically differentiated between flaps with and without occlusions as well as between flaps with venous occlusion and those with arterial occlusion based on these non-invasive optical measurements. Our preliminary results suggested that visible diffuse reflectance and autofluorescence spectroscopy can be potentially used clinically to detect both venous and arterial occlusion and differentiate one from the other accurately at an early time point.
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Affiliation(s)
- Caigang Zhu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637457, Singapore
- Currently with the Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Shuo Chen
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637457, Singapore
- Currently with the Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, 110819 China
| | | | - Bien-Keem Tan
- Department of Plastic, Reconstructive and Aesthetic Surgery, Singapore General Hospital, Singapore
| | - Quan Liu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 637457, Singapore
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12
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Prabitha VG, Suchetha S, Jayanthi JL, Baiju KV, Rema P, Anuraj K, Mathews A, Sebastian P, Subhash N. Detection of cervical lesions by multivariate analysis of diffuse reflectance spectra: a clinical study. Lasers Med Sci 2015; 31:67-75. [PMID: 26521184 DOI: 10.1007/s10103-015-1829-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/21/2015] [Indexed: 11/28/2022]
Abstract
Diffuse reflectance (DR) spectroscopy is a non-invasive, real-time, and cost-effective tool for early detection of malignant changes in squamous epithelial tissues. The present study aims to evaluate the diagnostic power of diffuse reflectance spectroscopy for non-invasive discrimination of cervical lesions in vivo. A clinical trial was carried out on 48 sites in 34 patients by recording DR spectra using a point-monitoring device with white light illumination. The acquired data were analyzed and classified using multivariate statistical analysis based on principal component analysis (PCA) and linear discriminant analysis (LDA). Diagnostic accuracies were validated using random number generators. The receiver operating characteristic (ROC) curves were plotted for evaluating the discriminating power of the proposed statistical technique. An algorithm was developed and used to classify non-diseased (normal) from diseased sites (abnormal) with a sensitivity of 72 % and specificity of 87 %. While low-grade squamous intraepithelial lesion (LSIL) could be discriminated from normal with a sensitivity of 56 % and specificity of 80 %, and high-grade squamous intraepithelial lesion (HSIL) from normal with a sensitivity of 89 % and specificity of 97 %, LSIL could be discriminated from HSIL with 100 % sensitivity and specificity. The areas under the ROC curves were 0.993 (95 % confidence interval (CI) 0.0 to 1) and 1 (95 % CI 1) for the discrimination of HSIL from normal and HSIL from LSIL, respectively. The results of the study show that DR spectroscopy could be used along with multivariate analytical techniques as a non-invasive technique to monitor cervical disease status in real time.
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Affiliation(s)
- Vasumathi Gopala Prabitha
- Biophotonics Laboratory, Centre for Earth Science Studies, Akkulam, Thiruvananthapuram, 695 031, Kerala, India
| | - Sambasivan Suchetha
- Regional Cancer Centre, Medical College P.O., Thiruvananthapuram, 695 011, Kerala, India
| | | | | | - Prabhakaran Rema
- Regional Cancer Centre, Medical College P.O., Thiruvananthapuram, 695 011, Kerala, India
| | - Koyippurath Anuraj
- Biophotonics Laboratory, Centre for Earth Science Studies, Akkulam, Thiruvananthapuram, 695 031, Kerala, India
| | - Anita Mathews
- Regional Cancer Centre, Medical College P.O., Thiruvananthapuram, 695 011, Kerala, India
| | - Paul Sebastian
- Regional Cancer Centre, Medical College P.O., Thiruvananthapuram, 695 011, Kerala, India
| | - Narayanan Subhash
- Biophotonics Laboratory, Centre for Earth Science Studies, Akkulam, Thiruvananthapuram, 695 031, Kerala, India. .,Sascan Meditech Pvt Ltd., CIME, BMS College of Engineering, Basavanagudi, Bull Temple Road, Bangalore, 560019, India.
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13
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Bergauer B, Knipfer C, Amann A, Rohde M, Tangermann-Gerk K, Adler W, Schmidt M, Nkenke E, Stelzle F. Does Laser Surgery Interfere with Optical Nerve Identification in Maxillofacial Hard and Soft Tissue?--An Experimental Ex Vivo Study. SENSORS 2015; 15:25416-32. [PMID: 26437416 PMCID: PMC4634421 DOI: 10.3390/s151025416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 09/09/2015] [Accepted: 09/28/2015] [Indexed: 11/16/2022]
Abstract
The protection of sensitive structures (e.g., nerves) from iatrogenic damage is of major importance when performing laser surgical procedures. Especially in the head and neck area both function and esthetics can be affected to a great extent. Despite its many benefits, the surgical utilization of a laser is therefore still limited to superficial tissue ablation. A remote feedback system which guides the laser in a tissue-specific way would provide a remedy. In this context, it has been shown that nerval structures can be specifically recognized by their optical diffuse reflectance spectra both before and after laser ablation. However, for a translation of these findings to the actual laser ablation process, a nerve protection within the laser pulse is of utmost significance. Thus, it was the aim of the study to evaluate, if the process of Er:YAG laser surgery--which comes with spray water cooling, angulation of the probe (60°) and optical process emissions--interferes with optical tissue differentiation. For the first time, no stable conditions but the ongoing process of laser tissue ablation was examined. Therefore, six different tissue types (nerve, skin, muscle, fat, cortical and cancellous bone) were acquired from 15 pig heads. Measurements were performed during Er:YAG laser ablation. Diffuse reflectance spectra (4500, wavelength range: 350-650 nm) where acquired. Principal component analysis (PCA) and quadratic discriminant analysis (QDA) were calculated for classification purposes. The clinical highly relevant differentiation between nerve and bone was performed correctly with an AUC of 95.3% (cortial bone) respectively 92.4% (cancellous bone). The identification of nerve tissue against the biological very similar fat tissue yielded good results with an AUC value of 83.4% (sensitivity: 72.3%, specificity: of 82.3%). This clearly demonstrates that nerve identification by diffuse reflectance spectroscopy works reliably in the ongoing process of laser ablation in spite of the laser beam, spray water cooling and the tissue alterations entailed by tissue laser ablation. This is an essential step towards a clinical utilization.
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Affiliation(s)
- Bastian Bergauer
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Christian Knipfer
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Andreas Amann
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Maximilian Rohde
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Katja Tangermann-Gerk
- Bavarian Laser Center GmbH (blz), Erlangen 91054, Germany.
- SAOT-Graduate School in Advanced Optical Technologies, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Werner Adler
- Department of Medical Informatics, Biometry and Epidemiology, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Michael Schmidt
- Bavarian Laser Center GmbH (blz), Erlangen 91054, Germany.
- SAOT-Graduate School in Advanced Optical Technologies, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
- Chair of Photonic Technologies, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
| | - Emeka Nkenke
- Department of Oral and Maxillofacial Surgery, Medical University of Vienna, Vienna 1090, Austria.
| | - Florian Stelzle
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
- SAOT-Graduate School in Advanced Optical Technologies, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Erlangen 91054, Germany.
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14
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Bregar M, Cugmas B, Naglic P, Hartmann D, Pernuš F, Likar B, Bürmen M. Properties of contact pressure induced by manually operated fiber-optic probes. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:127002. [PMID: 26720880 DOI: 10.1117/1.jbo.20.12.127002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 11/17/2015] [Indexed: 05/13/2023]
Abstract
We assess the properties of contact pressure applied by manually operated fiber-optic probes as a function of the operator, probe contact area, and sample stiffness. First, the mechanical properties of human skin sites with different skin structures, thicknesses, and underlying tissues were studied by in vivo indentation tests. According to the obtained results, three different homogeneous silicone skin phantoms were created to encompass the observed range of mechanical properties. The silicon phantoms were subsequently used to characterize the properties of the contact pressure by 10 experienced probe operators employing fiber-optic probes with different contact areas. A custom measurement system was used to collect the time-lapse of diffuse reflectance and applied contact pressure. The measurements were characterized by a set of features describing the transient and steady-state properties of the contact pressure and diffuse reflectance in terms of rise time, optical coupling, average value, and variability. The average applied contact pressure and contact pressure variability were found to significantly depend on the probe operator, probe contact area, and surprisingly also on the sample stiffness. Based on the presented results, we propose a set of practical guidelines for operators of manual probes.
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Affiliation(s)
- Maksimilijan Bregar
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Blaž Cugmas
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Peter Naglic
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Daniela Hartmann
- Ludwig-Maximilian University, Department of Dermatology and Allergology, Frauenlobstrasse 9-11, 80337 Munich, Germany
| | - Franjo Pernuš
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Boštjan Likar
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Miran Bürmen
- University of Ljubljana, Laboratory of Imaging Technologies, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
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15
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Yu B, Shah A, Nagarajan VK, Ferris DG. Diffuse reflectance spectroscopy of epithelial tissue with a smart fiber-optic probe. BIOMEDICAL OPTICS EXPRESS 2014; 5:675-89. [PMID: 24688805 PMCID: PMC3959852 DOI: 10.1364/boe.5.000675] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 02/01/2014] [Accepted: 02/05/2014] [Indexed: 05/20/2023]
Abstract
Diffuse reflectance spectroscopy (DRS) with a fiber-optic probe can noninvasively quantify the optical properties of epithelial tissues and has shown the potential as a cost-effective, fast and sensitive tool for diagnosis of early precancerous changes in the cervix and oral cavity. However, current DRS systems are susceptible to several sources of systematic and random errors, such as uncontrolled probe-to-tissue pressure and lack of a real-time calibration that can significantly impair the measurement accuracy, reliability and validity of this technology as well as its clinical utility. In addition, such systems use bulky, high power and expensive optical components which impede their widespread use in low- and middle-income countries (LMICs) where epithelial cancer related death is disproportionately high. In this paper we report a portable, easy-to-use and low cost, yet accurate and reliable DRS device that can aid in the screening and diagnosis of oral and cervical cancer. The device uses an innovative smart fiber-optic probe to eliminate operator bias, state-of-the-art photonics components to reduce size and power consumption, and automated software to reduce the need of operator training. The device showed a mean error of 1.4 ± 0.5% and 6.8 ± 1.7% for extraction of phantom absorption and reduced scattering coefficients, respectively. A clinical study on healthy volunteers indicated that a pressure below 1.0 psi is desired for oral mucosal tissues to minimize the probe effects on tissue physiology and morphology.
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Affiliation(s)
- Bing Yu
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA
| | - Amy Shah
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235, USA
| | - Vivek K. Nagarajan
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA
| | - Daron G. Ferris
- Department of Family Medicine and Obstetrics and Gynecology, Georgia Regents University, Augusta, GA 30912, USA
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16
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Tissue discrimination by uncorrected autofluorescence spectra: a proof-of-principle study for tissue-specific laser surgery. SENSORS 2013; 13:13717-31. [PMID: 24152930 PMCID: PMC3859088 DOI: 10.3390/s131013717] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 09/27/2013] [Indexed: 11/21/2022]
Abstract
Laser surgery provides a number of advantages over conventional surgery. However, it implies large risks for sensitive tissue structures due to its characteristic non-tissue-specific ablation. The present study investigates the discrimination of nine different ex vivo tissue types by using uncorrected (raw) autofluorescence spectra for the development of a remote feedback control system for tissue-selective laser surgery. Autofluorescence spectra (excitation wavelength 377 ± 50 nm) were measured from nine different ex vivo tissue types, obtained from 15 domestic pig cadavers. For data analysis, a wavelength range between 450 nm and 650 nm was investigated. Principal Component Analysis (PCA) and Quadratic Discriminant Analysis (QDA) were used to discriminate the tissue types. ROC analysis showed that PCA, followed by QDA, could differentiate all investigated tissue types with AUC results between 1.00 and 0.97. Sensitivity reached values between 93% and 100% and specificity values between 94% and 100%. This ex vivo study shows a high differentiation potential for physiological tissue types when performing autofluorescence spectroscopy followed by PCA and QDA. The uncorrected autofluorescence spectra are suitable for reliable tissue discrimination and have a high potential to meet the challenges necessary for an optical feedback system for tissue-specific laser surgery.
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17
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Pence IJ, Vargis E, Mahadevan-Jansen A. Assessing variability of in vivo tissue Raman spectra. APPLIED SPECTROSCOPY 2013; 67:789-800. [PMID: 23816132 DOI: 10.1366/12-06773] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Raman spectroscopy (RS) has received increasing attention as a potential tool for clinical diagnostics. However, the unknown comparability of multiple tissue RS systems remains a major issue for technique standardization and future multisystem trials. In this study, we evaluated potential factors affecting data collection and interpretation, utilizing the skin as an example tissue. The effects of contact pressure and probe angle were characterized as potential user-induced variability sources. Similarly, instrumentation-induced variability sources of system stability and system-dependent response were also analyzed on skin and a nonvolatile biological tissue analog. Physiologically induced variations were studied on multiple tissue locations and patients. The effect of variability sources on spectral line shape and dispersion was analyzed with analysis-of-variance methods, and a new metric for comparing spectral dispersion was defined. In this study, in vivo measurements were made on multiple sites of skin from five healthy volunteers, with four stand-alone fiber optic probe-based tissue RS systems. System stability and controlled user-induced variables had no effects on obtained spectra. By contrast, instrumentation and anatomical location of measurement were significant sources of variability. These findings establish the comparability of tissue Raman spectra obtained by unique systems. Furthermore, we suggest steps for further procedural and instrumentation standardization prior to broad clinical applications of the technique.
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Affiliation(s)
- Isaac J Pence
- Department of Biomedical Engineering, Vanderbilt University, Box 351631 Station B, Nashville, TN 37235, USA
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18
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Yadav N, Bhatia S, Ragheb J, Song Y, Romero A, Oh S, Lin WC. Evaluating and improving the quality of time-dependent, diffuse reflectance spectroscopic signals measured from in vivo brain during craniotomy. Med Eng Phys 2013; 35:1551-7. [PMID: 23665345 DOI: 10.1016/j.medengphy.2013.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 04/05/2013] [Accepted: 04/17/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Optical spectroscopy can be used to assess the pathophysiological characteristics of diseased and injured biological tissue in vivo in a non-destructive way. It is often used in conjunction with a contact optical probe for the purposes of operating and sensing in a sterile field. Since the probe is often held by the hand of an investigator during data acquisition, any hand instability can affect the quality of acquired data and, hence, degrade the accuracy of diagnosis. This study was designed to quantitatively characterize these artifacts, and then propose an effective engineering solution to remove them. METHODS Time-dependent diffuse reflectance spectra (Rd(λ,t)) were acquired from the normal cortex region of pediatric patients undergoing epilepsy surgery. They were acquired at a rate of 33 Hz, and their range was 400 and 900 nm. Two distinct ways of collecting data were tested: one with the fiber optical probe held by the surgeon's hand during data acquisition, and the other with the probe held by a specially designed probe holder. The probe holder was designed and constructed to minimize the variations in probe contact pressure and contact point for the full duration of any given investigation. Spectral data acquired using versus not using the probe holder were characterized and compared in the time, wavelength, and frequency domains, using both descriptive and inferential statistics. RESULTS Hand motion manifested as strong random variations in Rd(λ,t) which impacted temporal and frequency characteristics of Rd(λ,t). The percentage standard deviation %STD of Rd(λ,t) acquired without probe holder could be as high as 60%, and they are significantly higher than those with probe holder at all wavelengths. This difference is especially prominent between 400 and 600 nm. Rd(λ,t) acquired without the probe holder also processed a higher spectral power energy in the frequency domain than those with the probe holder. The correlation analysis revealed that the hand motions induced synchronistic variations in Rd(λ,t) between 600 and 800 nm, but this synchronicity is not obvious between 400 and 600 nm. CONCLUSION The results of this investigation demonstrate the nature and the magnitude of hand motion induced artifacts in in vivo diffuse reflectance spectra and propose one potential solution (i.e., a probe holder) to remove them. These findings allow us to improve the quality of time-dependent, diffuse reflectance signals acquired to study the dynamic characteristics of biological tissues, like brain, in vivo.
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Affiliation(s)
- Nitin Yadav
- Department of Biomedical Engineering, Florida International University, Miami, FL, USA.
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Ruderman S, Mueller S, Gomes A, Rogers J, Backman V. Method of detecting tissue contact for fiber-optic probes to automate data acquisition without hardware modification. BIOMEDICAL OPTICS EXPRESS 2013; 4:1401-12. [PMID: 24010002 PMCID: PMC3756576 DOI: 10.1364/boe.4.001401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 05/20/2023]
Abstract
We present a novel algorithm to detect contact with tissue and automate data acquisition. Contact fiber-optic probe systems are useful in noninvasive applications and real-time analysis of tissue properties. However, applications of these technologies are limited to procedures with visualization to ensure probe-tissue contact and individual user techniques can introduce variability. The software design exploits the system previously designed by our group as an optical method to automatically detect tissue contact and trigger acquisition. This method detected tissue contact with 91% accuracy, detected removal from tissue with 83% accuracy and reduced user variability by > 8%. Without the need for additional hardware, this software algorithm can easily integrate into any fiber-optic system and expands applications where visualization is difficult.
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Affiliation(s)
- Sarah Ruderman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208,
USA
| | - Scott Mueller
- American BioOptics, 1801 Maple Ave Evanston, IL 60201,
USA
| | - Andrew Gomes
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208,
USA
| | - Jeremy Rogers
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208,
USA
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208,
USA
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20
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Stelzle F, Terwey I, Knipfer C, Adler W, Tangermann-Gerk K, Nkenke E, Schmidt M. The impact of laser ablation on optical soft tissue differentiation for tissue specific laser surgery-an experimental ex vivo study. J Transl Med 2012; 10:123. [PMID: 22704127 PMCID: PMC3546422 DOI: 10.1186/1479-5876-10-123] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 05/16/2012] [Indexed: 11/10/2022] Open
Abstract
Background Optical diffuse reflectance can remotely differentiate various bio tissues. To implement this technique in an optical feedback system to guide laser surgery in a tissue-specific way, the alteration of optical tissue properties by laser ablation has to be taken into account. It was the aim of this study to evaluate the general feasibility of optical soft tissue differentiation by diffuse reflectance spectroscopy under the influence of laser ablation, comparing the tissue differentiation results before and after laser intervention. Methods A total of 70 ex vivo tissue samples (5 tissue types) were taken from 14 bisected pig heads. Diffuse reflectance spectra were recorded before and after Er:YAG-laser ablation. The spectra were analyzed and differentiated using principal component analysis (PCA), followed by linear discriminant analysis (LDA). To assess the potential of tissue differentiation, area under the curve (AUC), sensitivity and specificity was computed for each pair of tissue types before and after laser ablation, and compared to each other. Results Optical tissue differentiation showed good results before laser exposure (total classification error 13.51%). However, the tissue pair nerve and fat yielded lower AUC results of only 0.75. After laser ablation slightly reduced differentiation results were found with a total classification error of 16.83%. The tissue pair nerve and fat showed enhanced differentiation (AUC: 0.85). Laser ablation reduced the sensitivity in 50% and specificity in 80% of the cases of tissue pair comparison. The sensitivity of nerve–fat differentiation was enhanced by 35%. Conclusions The observed results show the general feasibility of tissue differentiation by diffuse reflectance spectroscopy even under conditions of tissue alteration by laser ablation. The contrast enhancement for the differentiation between nerve and fat tissue after ablation is assumed to be due to laser removal of the surrounding lipid-rich nerve sheath. The results create the basis for a guidance system to control laser ablation in a tissue-specific way.
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Affiliation(s)
- Florian Stelzle
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University of Erlangen-Nuremberg, Glückstrasse 11, 91054, Erlangen, Germany.
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21
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Vogt WC, Izquierdo-Román A, Nichols B, Lim L, Tunnell JW, Rylander CG. Effects of mechanical indentation on diffuse reflectance spectra, light transmission, and intrinsic optical properties in ex vivo porcine skin. Lasers Surg Med 2012; 44:303-9. [DOI: 10.1002/lsm.22018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/20/2012] [Indexed: 11/11/2022]
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22
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Buys TPH, Cantor SB, Guillaud M, Adler-Storthz K, Cox DD, Okolo C, Arulogon O, Oladepo O, Basen-Engquist K, Shinn E, Yamal JM, Beck JR, Scheurer ME, van Niekerk D, Malpica A, Matisic J, Staerkel G, Atkinson EN, Bidaut L, Lane P, Benedet JL, Miller D, Ehlen T, Price R, Adewole IF, MacAulay C, Follen M. Optical technologies and molecular imaging for cervical neoplasia: a program project update. ACTA ACUST UNITED AC 2011; 9:S7-24. [PMID: 21944317 DOI: 10.1016/j.genm.2011.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 08/02/2011] [Indexed: 12/23/2022]
Abstract
There is an urgent global need for effective and affordable approaches to cervical cancer screening and diagnosis. In developing nations, cervical malignancies remain the leading cause of cancer-related deaths in women. This reality may be difficult to accept given that these deaths are largely preventable; where cervical screening programs have been implemented, cervical cancer-related deaths have decreased dramatically. In developed countries, the challenges of cervical disease stem from high costs and overtreatment. The National Cancer Institute-funded Program Project is evaluating the applicability of optical technologies in cervical cancer. The mandate of the project is to create tools for disease detection and diagnosis that are inexpensive, require minimal expertise, are more accurate than existing modalities, and can be feasibly implemented in a variety of clinical settings. This article presents the status and long-term goals of the project.
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Affiliation(s)
- Timon P H Buys
- Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
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23
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Oh S, Stewart T, Miller I, Bhatia S, Ragheb J, Duchowny M, Jayakar P, Lin WC. In vivo optical properties of cortical tubers in children with tuberous sclerosis complex (TSC): a preliminary investigation. Epilepsia 2011; 52:1699-704. [DOI: 10.1111/j.1528-1167.2011.03167.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Cantor SB, Yamal JM, Guillaud M, Cox DD, Atkinson EN, Benedet JL, Miller D, Ehlen T, Matisic J, van Niekerk D, Bertrand M, Milbourne A, Rhodes H, Malpica A, Staerkel G, Nader-Eftekhari S, Adler-Storthz K, Scheurer ME, Basen-Engquist K, Shinn E, West LA, Vlastos AT, Tao X, Beck JR, MacAulay C, Follen M. Accuracy of optical spectroscopy for the detection of cervical intraepithelial neoplasia: Testing a device as an adjunct to colposcopy. Int J Cancer 2011; 128:1151-68. [PMID: 20830707 PMCID: PMC3015005 DOI: 10.1002/ijc.25667] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Accepted: 07/12/2010] [Indexed: 12/11/2022]
Abstract
Testing emerging technologies involves the evaluation of biologic plausibility, technical efficacy, clinical effectiveness, patient satisfaction, and cost-effectiveness. The objective of this study was to select an effective classification algorithm for optical spectroscopy as an adjunct to colposcopy and obtain preliminary estimates of its accuracy for the detection of CIN 2 or worse. We recruited 1,000 patients from screening and prevention clinics and 850 patients from colposcopy clinics at two comprehensive cancer centers and a community hospital. Optical spectroscopy was performed, and 4,864 biopsies were obtained from the sites measured, including abnormal and normal colposcopic areas. The gold standard was the histologic report of biopsies, read 2 to 3 times by histopathologists blinded to the cytologic, histopathologic, and spectroscopic results. We calculated sensitivities, specificities, receiver operating characteristic (ROC) curves, and areas under the ROC curves. We identified a cutpoint for an algorithm based on optical spectroscopy that yielded an estimated sensitivity of 1.00 [95% confidence interval (CI) = 0.92-1.00] and an estimated specificity of 0.71 [95% CI = 0.62-0.79] in a combined screening and diagnostic population. The positive and negative predictive values were 0.58 and 1.00, respectively. The area under the ROC curve was 0.85 (95% CI = 0.81-0.89). The per-patient and per-site performance were similar in the diagnostic and poorer in the screening settings. Like colposcopy, the device performs best in a diagnostic population. Alternative statistical approaches demonstrate that the analysis is robust and that spectroscopy works as well as or slightly better than colposcopy for the detection of CIN 2 to cancer.
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Affiliation(s)
- Scott B. Cantor
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jose-Miguel Yamal
- Division of Biostatistics, The University of Texas School of Public Health, Houston, Texas
| | - Martial Guillaud
- Department of Cancer Imaging, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Dennis D. Cox
- Department of Statistics, Rice University, Houston, Texas
| | - E. Neely Atkinson
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - J. L. Benedet
- Department of Cancer Imaging, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Dianne Miller
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Thomas Ehlen
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jasenka Matisic
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dirk van Niekerk
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Monique Bertrand
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrea Milbourne
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Helen Rhodes
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Anais Malpica
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gregg Staerkel
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Shahla Nader-Eftekhari
- Department of Obstetrics, Gynecology, and Reproductive Sciences, The University of Texas Health Science Center at Houston, Houston, Texas
| | - Karen Adler-Storthz
- The University of Texas Health Science Center at Houston Dental Branch, Houston, Texas
| | - Michael E. Scheurer
- Department of Pediatrics and Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, Texas
| | - Karen Basen-Engquist
- Department of Behavioral Science, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Eileen Shinn
- Department of Behavioral Science, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Loyd A. West
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Anne-Therese Vlastos
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Xia Tao
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Calum MacAulay
- Department of Cancer Imaging, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Michele Follen
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Obstetrics, Gynecology, and Reproductive Sciences, The University of Texas Health Science Center at Houston, Houston, Texas
- Department of Obstetrics, Gynecology, and Reproductive Sciences, the Lyndon Baines Johnson Hospital, Houston, Texas
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25
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Lim L, Nichols B, Rajaram N, Tunnell JW. Probe pressure effects on human skin diffuse reflectance and fluorescence spectroscopy measurements. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:011012. [PMID: 21280899 PMCID: PMC3041811 DOI: 10.1117/1.3525288] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Diffuse reflectance and fluorescence spectroscopy are popular research techniques for noninvasive disease diagnostics. Most systems include an optical fiber probe that transmits and collects optical spectra in contact with the suspected lesion. The purpose of this study is to investigate probe pressure effects on human skin spectroscopic measurements. We conduct an in-vivo experiment on human skin tissue to study the short-term (<2 s) and long-term (>30 s) effects of probe pressure on diffuse reflectance and fluorescence measurements. Short-term light probe pressure (P0<9 mN∕mm2) effects are within 0 ± 10% on all physiological properties extracted from diffuse reflectance and fluorescence measurements, and less than 0±5% for diagnostically significant physiological properties. Absorption decreases with site-specific variations due to blood being compressed out of the sampled volume. Reduced scattering coefficient variation is site specific. Intrinsic fluorescence shows a large standard error, although no specific pressure-related trend is observed. Differences in tissue structure and morphology contribute to site-specific probe pressure effects. Therefore, the effects of pressure can be minimized when the pressure is small and applied for a short amount of time; however, long-term and large pressures induce significant distortions in measured spectra.
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Affiliation(s)
- Liang Lim
- The University of Texas at Austin, Department of Biomedical Engineering, 1 University Station C0800, Austin, Texas 78712, USA.
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26
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Yamal JM, Cox DD, Atkinson EN, MacAulay C, Price R, Follen M. Repeatability of tissue fluorescence measurements for the detection of cervical intraepithelial neoplasia. BIOMEDICAL OPTICS EXPRESS 2010; 1:641-657. [PMID: 21258497 PMCID: PMC3018008 DOI: 10.1364/boe.1.000641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/05/2010] [Accepted: 08/17/2010] [Indexed: 05/16/2023]
Abstract
We examined intensity and shape differences in 378 repeated spectroscopic measures of the cervix. We examined causes of variability such as presence of precancer or cancer, pathologic tissue type, menopausal status, hormone or oral contraceptive use, and age; as well as technology related variables like generation of device and provider making exam. Age, device generation, and provider were statistically significantly related to intensity differences. Provider and device generation were related to shape differences. We examined the order of measurements and found a decreased intensity in the second measurement due to hemoglobin absorption. 96% of repeat measurements had classification concordance of cervical intraepithelial neoplasia.
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Affiliation(s)
- José-Miguel Yamal
- Division of Biostatistics, The University of Texas School of Public Health,
1200 Herman Pressler, Houston, TX 77030, USA
| | - Dennis D. Cox
- Department of Statistics, Rice University, 6100 Main St, Houston, Texas 77030, USA
| | - E. Neely Atkinson
- Department of Biostatistics, The University of Texas M. D. Anderson Cancer Center,
1515 Holcombe Blvd, Houston, Texas 77030, USA
| | - Calum MacAulay
- Department of Cancer Imaging, British Columbia Cancer Research Centre,
600 West 10 Ave.,Vancouver, British Columbia V5Z 4E6, Canada
| | - Roderick Price
- Department of Obstetrics and Gynecology, The Institute for Women’s Health, 245 N. 15th St., Philadelphia, Pennsylvania 19102, USA
| | - Michele Follen
- Department of Obstetrics and Gynecology, The Institute for Women’s Health, 245 N. 15th St., Philadelphia, Pennsylvania 19102, USA
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27
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Ruderman S, Gomes AJ, Stoyneva V, Rogers JD, Fought AJ, Jovanovic BD, Backman V. Analysis of pressure, angle and temporal effects on tissue optical properties from
polarization-gated spectroscopic probe measurements. BIOMEDICAL OPTICS EXPRESS 2010; 1:489-499. [PMID: 21258484 PMCID: PMC3017986 DOI: 10.1364/boe.1.000489] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 07/24/2010] [Accepted: 08/02/2010] [Indexed: 05/03/2023]
Abstract
Noninvasive optical techniques for tissue characterization, in particular, light scattering properties and blood supply quantification of mucosa, is useful in a wide variety of applications. However, fiber-optic probes that require contact with the tissue surface can present a challenging problem in the variability of in vivo measurements due the nature of interactions, for example affects due to variations in pressure applied to the probe tip. We present an in vivo evaluation of pressure, angle, and temporal effects on tissue properties for polarization-gated spectroscopy at superficial depths (within 100 to 200 microns of tissue surface) for oral mucosa.
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Affiliation(s)
- Sarah Ruderman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA
| | - Andrew J. Gomes
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA
| | - Valentina Stoyneva
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA
| | - Jeremy D. Rogers
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA
| | - Angela J. Fought
- Department of Preventative Medicine, Northwestern University Medical School, 680 North Lake Shore Drive,
Suite 1400, Evanston, IL 60208, USA
| | - Borko D. Jovanovic
- Department of Preventative Medicine, Northwestern University Medical School, 680 North Lake Shore Drive,
Suite 1400, Evanston, IL 60208, USA
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA
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Delgado Atencio JA, Orozco Guillén EE, Vázquez y Montiel S, Cunill Rodríguez M, Castro Ramos J, Gutiérrez JL, Martínez F. Influence of probe pressure on human skin diffuse reflectance spectroscopy measurements. ACTA ACUST UNITED AC 2009. [DOI: 10.3103/s1060992x09010020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Brown JQ, Vishwanath K, Palmer GM, Ramanujam N. Advances in quantitative UV-visible spectroscopy for clinical and pre-clinical application in cancer. Curr Opin Biotechnol 2009; 20:119-31. [PMID: 19268567 DOI: 10.1016/j.copbio.2009.02.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 02/05/2009] [Indexed: 11/29/2022]
Abstract
Methods of optical spectroscopy that provide quantitative, physically or physiologically meaningful measures of tissue properties are an attractive tool for the study, diagnosis, prognosis, and treatment of various cancers. Recent development of methodologies to convert measured reflectance and fluorescence spectra from tissue to cancer-relevant parameters such as vascular volume, oxygenation, extracellular matrix extent, metabolic redox states, and cellular proliferation have significantly advanced the field of tissue optical spectroscopy. The number of publications reporting quantitative tissue spectroscopy results in the UV-visible wavelength range has increased sharply in the past three years, and includes new and emerging studies that correlate optically measured parameters with independent measures such as immunohistochemistry, which should aid in increased clinical acceptance of these technologies.
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Affiliation(s)
- J Quincy Brown
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
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Nieman LT, Kan CW, Gillenwater A, Markey MK, Sokolov K. Probing local tissue changes in the oral cavity for early detection of cancer using oblique polarized reflectance spectroscopy: a pilot clinical trial. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:024011. [PMID: 18465974 DOI: 10.1117/1.2907450] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report the results of an oral cavity pilot clinical trial to detect early precancer and cancer using a fiber optic probe with obliquely oriented collection fibers that preferentially probe local tissue morphology and heterogeneity using oblique polarized reflectance spectroscopy (OPRS). We extract epithelial cell nuclear sizes and 10 spectral features. These features are analyzed independently and in combination to assess the best metrics for separation of diagnostic classes. Without stratifying the data according to anatomical location or level of keratinization, OPRS is found to be sensitive to four diagnostic categories: normal, benign, mild dysplasia, high-grade dysplasia, and carcinoma. Using linear discriminant analysis, separation of normal from high-grade dysplasia and carcinoma yield a sensitivity and specificity of 90 and 86%, respectively. Discrimination of morphologically similar lesions such as normal from mild dysplasia is achieved with a sensitivity of 75% and specificity of 73%. Separation of visually indistinguishable benign lesions from high-grade dysplasia and carcinoma is achieved with good sensitivity (100%) and specificity (85%), while separation of benign from mild dysplasia gives a sensitivity of 92% and a specificity of 69%. These promising results suggest that OPRS has the potential to aid screening and diagnosis of oral precancer and cancer.
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Affiliation(s)
- Linda T Nieman
- The University of Texas M. D. Anderson Cancer Center, Department of Biomedical Engineering, 1515 Holcombe Boulevard, Houston, Texas 77030, USA
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Reif R, Amorosino MS, Calabro KW, A'Amar O, Singh SK, Bigio IJ. Analysis of changes in reflectance measurements on biological tissues subjected to different probe pressures. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:010502. [PMID: 18315347 DOI: 10.1117/1.2870115] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Spectral reflectance measurements of biological tissues have been studied for early diagnoses of several pathologies such as cancer. These measurements are often performed with a fiber optic probe in contact with the tissue surface. We report a study in which reflectance measurements are obtained in vivo from mouse thigh muscle while varying the contact pressure of the fiber optic probe. It is determined that the probe pressure is a variable that affects the local optical properties of the tissue. The reflectance spectra are analyzed with an analytical model that extracts the tissue optical properties and facilitates the understanding of underlying physiological changes induced by the probe pressure.
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Affiliation(s)
- Roberto Reif
- Boston University, Department of Biomedical Engineering, 44 Cummington Street, Boston, Massachusetts 02215, USA.
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Lee JS, Follen M, MacAulay C, Pikkula B, Serachitopol D, Price R, Cox D. Sources of variability in fluorescence spectroscopic measurements in a Phase II clinical trial of 850 patients. Gynecol Oncol 2007; 107:S260-9. [PMID: 17825398 DOI: 10.1016/j.ygyno.2007.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 07/06/2007] [Indexed: 10/22/2022]
Abstract
BACKGROUND Devices using fluorescence spectroscopy to differentiate high grade squamous intraepithelial lesions from normal tissue in the cervix have shown some diagnostic efficacy. Measurements from these devices produce large amounts of complex, multi-factored data. The purpose of this study is to isolate the effects of the particular care providers and equipment operators who are involved in taking measurements. METHODS Data from spectroscopic measurements of the Phase II study of 850 patients with abnormal Papancicolau smears were used. The data were subject to a Principal Components Analysis and to MANOVA to control for variables that are known to affect outcomes. RESULTS The analysis showed significant provider effects from both devices and significant operator effects from one device. CONCLUSION We will repeat a similar analysis on data from a screening trial, on the combined diagnostic and screening study, and on the reflectance data. In the future, we hope to be able to design devices that address provider and operator effects.
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Affiliation(s)
- Jong Soo Lee
- Carnegie Mellon University, Department of Statistics, Pittsburgh, PA 15213, USA
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Majumder SK, Ghosh N, Gupta PK. Relevance vector machine for optical diagnosis of cancer. Lasers Surg Med 2005; 36:323-33. [PMID: 15825208 DOI: 10.1002/lsm.20160] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND OBJECTIVES A probability-based, robust diagnostic algorithm is an essential requirement for successful clinical use of optical spectroscopy for cancer diagnosis. This study reports the use of the theory of relevance vector machine (RVM), a recent Bayesian machine-learning framework of statistical pattern recognition, for development of a fully probabilistic algorithm for autofluorescence diagnosis of early stage cancer of human oral cavity. It also presents a comparative evaluation of the diagnostic efficacy of the RVM algorithm with that based on support vector machine (SVM) that has recently received considerable attention for this purpose. STUDY DESIGN/MATERIALS AND METHODS The diagnostic algorithms were developed using in vivo autofluorescence spectral data acquired from human oral cavity with a N(2) laser-based portable fluorimeter. The spectral data of both patients as well as normal volunteers, enrolled at Out Patient department of the Govt. Cancer Hospital, Indore for screening of oral cavity, were used for this purpose. The patients selected had no prior confirmed malignancy and were diagnosed of squamous cell carcinoma (SCC), Grade-I on the basis of histopathology of biopsy taken from abnormal site subsequent to acquisition of spectra. Autofluorescence spectra were recorded from a total of 171 tissue sites from 16 patients and 154 healthy squamous tissue sites from 13 normal volunteers. Of 171 tissues sites from patients, 83 were SCC and the rest were contralateral uninvolved squamous tissue. Each site was treated separately and classified via the diagnostic algorithm developed. Instead of the spectral data from uninvolved sites of patients, the data from normal volunteers were used as the normal database for the development of diagnostic algorithms. RESULTS The diagnostic algorithms based on RVM were found to provide classification performance comparable to the state-of-the-art SVMs, while at the same time explicitly predicting the probability of class membership. The sensitivity and specificity towards cancer were up to 88% and 95% for the training set data based on leave- one-out cross validation and up to 91% and 96% for the validation set data. When implemented on the spectral data of the uninvolved oral cavity sites from the patients, it yielded a specificity of up to 91%. CONCLUSIONS The Bayesian framework of RVM formulation makes it possible to predict the posterior probability of class membership in discriminating early SCC from the normal squamous tissue sites of the oral cavity in contrast to dichotomous classification provided by the non-Bayesian SVM. Such classification is very helpful in handling asymmetric misclassification costs like assigning different weights for having a false negative result for identifying cancer compared to false positive. The results further demonstrate that for comparable diagnostic performances, the RVM-based algorithms use significantly fewer kernel functions and do not need to estimate any hoc parameters associated with the learning or the optimization technique to be used. This implies a considerable saving in memory and computation in a practical implementation.
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Affiliation(s)
- Shovan K Majumder
- Biomedical Applications Section, Centre for Advanced Technology, Indore 452013, India.
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Rivoire K, Nath A, Cox D, Atkinson EN, Richards-Kortum R, Follen M. The effects of repeated spectroscopic pressure measurements on fluorescence intensity in the cervix. Am J Obstet Gynecol 2004; 191:1606-17. [PMID: 15547531 DOI: 10.1016/j.ajog.2004.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Fluorescence spectroscopy is a promising technology for the detection of cervical squamous intraepithelial lesions (SILs). In this study we took repeated measures in the cervix to determine whether the order of measurement produces changes in fluorescence intensity and whether there are differences in variation due to pressure. METHODS A pressure sensitive fiber-optic probe to measure fluorescence spectra was calibrated at light, medium, and firm levels (0.2, 0.4, 0.6 N). Measurements were made 3 times at each of 2 sites in the patient's cervix. Spectroscopic data were preprocessed and analyzed to compare order of pressure and intensity variability as a function of pressure on measurements. RESULTS Four providers took 3 measurements from 2 sites each in 18 patients, yielding 108 measurements. After corrections for multiple comparisons, neither the order of probe pressure nor the variability of probe pressure significantly affected variations in fluorescence intensity. CONCLUSION This study shows that the probe pressure variability is probably not an issue for these devices.
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Affiliation(s)
- Kelley Rivoire
- Center for Biomedical Engineering, Department of Biostatistics and Applied Mathematics, The University of Texas M. D. Anderson Cancer Center, Houston, Tex, USA
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