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Effect of glucose on the optical properties of arterial blood using Mie theory simulations

Neil T. Clancy, Martin J. Leahy, Mary-Ann Mycek
2005 Diagnostic Optical Spectroscopy in Biomedicine III  
The glucose concentration in arterial plasma has immediate effects on the optical properties of blood-bearing tissue due primarily to the alteration of refractive index mismatch between the scattering particles (red blood cells) and the medium (plasma). The influence of these effects on pulse oximetry is investigated using a numerical model based on Mie theory. The objective is to determine whether or not physiological fluctuations in blood glucose levels could sufficiently vary the optical
more » ... ary the optical properties to shift the calibration curve of a commercial pulse oximeter significantly.
doi:10.1117/12.633039 fatcat:4hmefy6vvje2dmv4feykb675ea

Multidimension potential of surface plasmon resonance imaging for dynamic surface characterization: application to optical biochips

P. Lecaruyer, E. Maillart, M. Canva, J. Rolland, Mary-Ann Mycek
2005 Diagnostic Optical Spectroscopy in Biomedicine III  
We have realized a surface plasmon resonance imaging system allowing accurate characterization of biochips. In this paper, the Rouard approach is extended to absorbing layers to model the reflectivity information contained in the multidimensional data. The multidimension potential is also expressed to demonstrate the power of the SPR imaging system. To conclude, towards the development of a biosensor based on SPR, a theoretical study is also performed on the sensitivity to changes in
more » ... anges in reflectivity of such multidimension optical biosensor. The sensitivity of the sytem shows the power of this biophotonic technology.
doi:10.1117/12.633021 fatcat:fcxazxroavgfnei55gxi2n6bcq

Quantitative molecular sensing in biological tissues: an approach to non-invasive optical characterization

Malavika Chandra, Karthik Vishwanath, Greg D. Fichter, Elly Liao, Scott J. Hollister, Mary-Ann Mycek
2006 Optics Express  
Mycek, ed., Proc. SPIE-OSA Biomedical Optics 5862, 58620T (2005).  ...  employed a pulsed, solid-state laser source (PNV001525-140, JDS Uniphase, San Jose, CA) with an adjustable repetition rate (1-10 3 Hz) emitting at 355 nm with a 500 ps pulse width and an energy of 15 μ J/  ... 
doi:10.1364/oe.14.006157 pmid:19516787 fatcat:bbsvbxzqbfbh7dxxr7aivprquq

Characterization of squamous cell carcinoma in an organotypic culture via subsurface non-linear optical molecular imaging

Christina S Scanlon, Elizabeth A Van Tubergen, Leng-Chun Chen, Sakib F Elahi, Shiuhyang Kuo, Stephen Feinberg, Mary-Ann Mycek, Nisha J D'Silva
2013 Experimental biology and medicine  
fluorescence images of GFP-expressing cells and SHG images of collagen from the OCE scaffold were pseudo-colored green and blue, respectively, and then merged in 8-bit RGB color format using NIH Image J  ... 
doi:10.1177/1535370213502628 pmid:24085785 pmcid:PMC4216589 fatcat:ztsucjsstfbcddd2ytr6krvgl4

Needle-compatible miniaturized optoelectronic sensor for pancreatic cancer detection

Seung Yup Lee, Julia M. Pakela, Kyounghwan Na, Jiaqi Shi, Barbara J. McKenna, Diane M. Simeone, Euisik Yoon, James M. Scheiman, Mary-Ann Mycek
2020 Science Advances  
Kampasi for eutectic bonding, J. K. Woo for wire bonding, I. Shin and G. Cheon for the control electronics and GUI program, and J. Ahn for thermal simulation. Last, we appreciate R.  ...  (J) Emission wavelengths of three LEDs measured by spectrophotometer.  ... 
doi:10.1126/sciadv.abc1746 pmid:33219025 pmcid:PMC7679167 fatcat:gowlezwkrngwbkdyxfbtufgxze

Multi-wavelength transmittance photoplethysmography with near infrared laser diodes during exercise

S. M. Lopez Silva, R. Giannetti, M. L. Dotor, D. Golmayo, P. Martin, F. Miguel-Tobal, A. Bilbao, J. P. Silveira, Mary-Ann Mycek
2005 Diagnostic Optical Spectroscopy in Biomedicine III  
The transmittance photoplethysmographyc signals recorded with multiple NIR laser diodes in athletes along a maximal exercise test by treadmill ergometer and the results after processing are presented in comparison to the established reference techniques. The Heart Rates obtained with our NIR LD sensory system over maximal exercise tests in athletes, agree with those obtained by ECG.
doi:10.1117/12.633042 fatcat:bfiec26pbvdidbaiyd35mkwjxe

Tissue Classification Using Optical Spectroscopy Accurately Differentiates Cancer and Chronic Pancreatitis

Robert H. Wilson, Malavika Chandra, James M. Scheiman, Seung Yup Lee, Oliver E. Lee, Barbara J. McKenna, Diane M. Simeone, Jeremy M.G. Taylor, Mary-Ann Mycek
2017 Pancreas  
J. Purdy for histopathological analysis. We thank S. Korsnes  ... 
doi:10.1097/mpa.0000000000000732 pmid:27861201 pmcid:PMC5235923 fatcat:wcz4ovnh6vgjzf3ziwonfmnhmu

Quantitative measurement and control of oxygen levels in microfluidic poly(dimethylsiloxane) bioreactors during cell culture

Geeta Mehta, Khamir Mehta, Dhruv Sud, Jonathan W. Song, Tommaso Bersano-Begey, Nobuyuki Futai, Yun Seok Heo, Mary-Ann Mycek, Jennifer J. Linderman, Shuichi Takayama
2006 Biomedical microdevices  
Microfluidic bioreactors fabricated from highly gas-permeable poly(dimethylsiloxane) (PDMS) materials have been observed, somewhat unexpectedly, to give rise to heterogeneous long term responses along the length of a perfused mammalian cell culture channel, reminiscent of physiologic tissue zonation that arises at least in part due to oxygen gradients. To develop a more quantitative understanding and enable better control of the physical-chemical mechanisms underlying cell biological events in
more » ... ological events in such PDMS reactors, dissolved oxygen concentrations in the channel system were quantified in real time using fluorescence intensity and lifetime imaging of an oxygen sensitive dye, ruthenium tris(2,2'-dipyridyl) dichloride hexahydrate (RTDP). The data Electronic Supplementary Material is available in the online version of this article at http://dx.indicate that despite oxygen diffusion through PDMS, uptake of oxygen by cells inside the perfused PDMS microchannels induces an axial oxygen concentration gradient, with lower levels recorded in downstream regions. The oxygen concentration gradient generated by a balance of cellular uptake, convective transport by media flow, and permeation through PDMS in our devices ranged from 0.0003 (mg/l)/mm to 0.7 (mg/l)/mm. The existence of such steep gradients induced by cellular uptake can have important biological consequences. Results are consistent with our mathematical model and give insight into the conditions under which flux of oxygen through PDMS into the microchannels will or will not contribute significantly to oxygen delivery to cells and also provide a design tool to manipulate and control oxygen for cell culture and device engineering. The combination of computerized microfluidics, in situ oxygen sensing, and mathematical models opens new windows for microphysiologic studies utilizing oxygen gradients and low oxygen tensions.
doi:10.1007/s10544-006-9005-7 pmid:17160707 fatcat:cd4jivhjzzbjbingoejpfucaku

A compact instrument to measure perfusion of vasculature in transplanted maxillofacial free flaps

Noah J. Kolodziejski, Christopher J. Stapels, Daniel R. McAdams, Daniel E. Fernandez, Matthew J. Podolsky, Dana Farkas, Brent B. Ward, Mark Vartarian, Stephen E. Feinberg, Seung Yup Lee, Urmi Parikh, Mary-Ann Mycek (+2 others)
2016 Optical Diagnostics and Sensing XVI: Toward Point-of-Care Diagnostics  
The vascularization and resulting perfusion of transferred tissues are critical to the success of grafts in buried free flap transplantations. To enable long-term clinical monitoring of grafted tissue perfusion during neovascularization and endothelialization, we are developing an implantable instrument for the continuous monitoring of perfusion using diffuse correlation spectroscopy (DCS), and augmented with diffuse reflectance spectroscopy (DRS). This work discusses instrument construction,
more » ... ent construction, integration, and preliminary results using a porcine graft model.
doi:10.1117/12.2212872 pmid:29706686 pmcid:PMC5916819 fatcat:sgjzwseibjhzxm2d4732ofrw5q

Design verification of a compact system for detecting tissue perfusion using bimodal diffuse optical technologies

Julia M. Pakela, Taylor L. Hedrick, Seung Yup Lee, Karthik Vishwanath, Sara Zanfardino, Yooree G. Chung, Michael C. Helton, Noah J. Kolodziejski, Christopher J. Stapels, Daniel R. McAdams, Daniel E. Fernandez, James F. Christian (+3 others)
2017 Optical Diagnostics and Sensing XVII: Toward Point-of-Care Diagnostics  
It is essential to monitor tissue perfusion during and after reconstructive surgery, as restricted blood flow can result in graft failures. Current clinical procedures are insufficient to monitor tissue perfusion, as they are intermittent and often subjective. To address this unmet clinical need, a HHS Public Access
doi:10.1117/12.2252811 pmid:29755163 pmcid:PMC5946689 fatcat:rkkwt6aagzfldoh54j7l6765n4

A disposable flexible skin patch for clinical optical perfusion monitoring at multiple depths

Dana L. Farkas, Noah J. Kolodziejski, Christopher J. Stapels, Daniel R. McAdams, Daniel E. Fernandez, Matthew J. Podolsky, James F. Christian, Brent B. Ward, Mark Vartarian, Stephen E. Feinberg, Seung Yup Lee, Urmi Parikh (+5 others)
2016 Optical Diagnostics and Sensing XVI: Toward Point-of-Care Diagnostics  
Stable, relative localization of source and detection fibers is necessary for clinical implementation of quantitative optical perfusion monitoring methods such as diffuse correlation spectroscopy (DCS) and diffuse reflectance spectroscopy (DRS). A flexible and compact device design is presented as a platform for simultaneous monitoring of perfusion at a range of depths, enabled by precise location of optical fibers in a robust and secure adhesive patch. We will discuss preliminary data
more » ... inary data collected on human subjects in a lower body negative pressure model for hypovolemic shock. These data indicate that this method facilitates simple and stable simultaneous monitoring of perfusion at multiple depths and within multiple physiological compartments.
doi:10.1117/12.2230988 pmid:29056813 pmcid:PMC5647776 fatcat:erkxvk3i2nd6vej4lda5sqpemq

In vivo preclinical verification of a multimodal diffuse reflectance and correlation spectroscopy system for sensing tissue perfusion

Julia M. Pakela, Seung Yup Lee, Taylor L. Hedrick, Karthik Vishwanath, Michael C. Helton, Yooree G. Chung, Noah J. Kolodziejski, Christopher J. Staples, Daniel R. McAdams, Daniel E. Fernandez, James F. Christian, Jameson O'Reilly (+5 others)
2017 Optical Diagnostics and Sensing XVII: Toward Point-of-Care Diagnostics  
In reconstructive surgery, impeded blood flow in microvascular free flaps due to a compromise in arterial or venous patency secondary to blood clots or vessel spasms can rapidly result in flap failures. Thus, the ability to detect changes in microvascular free flaps is critical. In this paper, we report progress on in vivo pre-clinical testing of a compact, multimodal, fiber-based diffuse correlation and reflectance spectroscopy system designed to quantitatively monitor tissue perfusion in a
more » ... e perfusion in a porcine model's surgically-grafted free flap. We also describe the device's sensitivity to incremental blood flow changes and discuss the prospects for continuous perfusion monitoring in future clinical translational studies.
doi:10.1117/12.2252620 pmid:29706683 pmcid:PMC5916836 fatcat:4prboiry3zam7epnowdihaencq

Novel diffuse optics system for continuous tissue viability monitoring: extended recovery in vivo testing in a porcine flap model

Seung Yup Lee, Julia M. Pakela, Taylor L. Hedrick, Karthik Vishwanath, Michael C. Helton, Yooree Chung, Noah J. Kolodziejski, Christopher J. Stapels, Daniel R. McAdams, Daniel E. Fernandez, James F. Christian, Jameson O'Reilly (+7 others)
2017 Advanced Biomedical and Clinical Diagnostic and Surgical Guidance Systems XV  
In reconstructive surgery, tissue perfusion/vessel patency is critical to the success of microvascular free tissue flaps. Early detection of flap failure secondary to compromise of vascular perfusion would significantly increase the chances of flap salvage. We have developed a compact, clinically-compatible monitoring system to enable automated, minimally-invasive, continuous, and quantitative assessment of flap viability/perfusion. We tested the system's continuous monitoring capability during
more » ... g capability during extended non-recovery surgery using an in vivo porcine free flap model. Initial results indicated that the system could assess flap viability/perfusion in a quantitative and continuous manner. With proven performance, the compact form constructed with cost-effective components would make this system suitable for clinical translation.
doi:10.1117/12.2252295 pmid:29706680 pmcid:PMC5916821 fatcat:jz2bqbzlvvh55nez4dxilhu2iy