Wide field continuous wave reflectance optical topography including a clear layer on top of the diffusive surface

2017 ◽  
Vol 25 (3) ◽  
pp. 165-171 ◽  
Author(s):  
NA Carbone ◽  
DI Iriarte ◽  
JA Pomarico
Keyword(s):  
Experimental Study ◽  
Diffuse Reflectance ◽  
Near Infrared ◽  
Continuous Wave ◽  
Flat Surface ◽  
Clinical Applications ◽  
Wide Field ◽  
Optical Mammography ◽  
Index Matching ◽  
Optical Topography

This work considers some experimental details which complement the results of a previous paper concerned with wide field near infrared continuous wave diffuse reflectance optical mammography. Different from the case of phantoms, clinical applications require some transparent interface between the breast and the camera. This interface provides the necessary flat surface to be imaged by the camera. We present an experimental study which compares the performance of the method when such an interface is present, to the case of the exposed phantom’s surface presented in that previous paper. Several index matching materials were also included in the study and a validation using Monte Carlo is presented.

scholarly journals Assessment of fNIRS Signal Processing Pipelines: Towards Clinical Applications

2021 ◽  
Vol 12 (1) ◽  
pp. 316
Author(s):  
Augusto Bonilauri ◽  
Francesca Sangiuliano Intra ◽  
Giuseppe Baselli ◽  
Francesca Baglio
Keyword(s):  
Signal Processing ◽  
Near Infrared ◽  
Continuous Wave ◽  
Single Channel ◽  
Model Fitting ◽  
Principal Component ◽  
Clinical Applications ◽  
Single Subject ◽  
Hemodynamic Response Function ◽  
Functional Near Infrared Spectroscopy

Functional Near-Infrared Spectroscopy (fNIRS) captures activations and inhibitions of cortical areas and implements a viable approach to neuromonitoring in clinical research. Compared to more advanced methods, continuous wave fNIRS (CW-fNIRS) is currently used in clinics for its simplicity in mapping the whole sub-cranial cortex. Conversely, it often lacks hardware reduction of confounding factors, stressing the importance of a correct signal processing. The proposed pipeline includes movement artifact reduction (MAR), bandpass filtering (BPF), and principal component analysis (PCA). Eight MAR algorithms were compared among 23 young adult volunteers under motor-grasping task. Single-subject examples are shown followed by the percentage in energy reduction (ERD%) statistics by single steps and cumulative values. The block average of the hemodynamic response function was compared with generalized linear model fitting. Maps of significant activation/inhibition were illustrated. The mean ERD% of pre-processed signals concerning the initial raw signal energy reached 4%. A tested multichannel MAR variant showed overcorrection on 4-fold more expansive windows. All of the MAR algorithms found similar activations in the contralateral motor area. In conclusion, single channel MAR algorithms are suggested followed by BPF and PCA. The importance of whole cortex mapping for fNIRS integration in clinical applications was also confirmed by our results.

scholarly journals Time-Domain Near-Infrared Spectroscopy and Imaging: A Review

2019 ◽  
Vol 9 (6) ◽  
pp. 1127 ◽  
Author(s):  
Yukio Yamada ◽  
Hiroaki Suzuki ◽  
Yutaka Yamashita
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Time Domain ◽  
Near Infrared ◽  
Continuous Wave ◽  
Theoretical Background ◽  
Clinical Applications ◽  
Time Resolved ◽  
The Past ◽  
Near Future

This article reviews the past and current statuses of time-domain near-infrared spectroscopy (TD-NIRS) and imaging. Although time-domain technology is not yet widely employed due to its drawbacks of being cumbersome, bulky, and very expensive compared to commercial continuous wave (CW) and frequency-domain (FD) fNIRS systems, TD-NIRS has great advantages over CW and FD systems because time-resolved data measured by TD systems contain the richest information about optical properties inside measured objects. This article focuses on reviewing the theoretical background, advanced theories and methods, instruments, and studies on clinical applications for TD-NIRS including some clinical studies which used TD-NIRS systems. Major events in the development of TD-NIRS and imaging are identified and summarized in chronological tables and figures. Finally, prospects for TD-NIRS in the near future are briefly described.

scholarly journals Oxide Bioceramic Composites in Orthopedics and Dentistry

2021 ◽  
Vol 5 (8) ◽  
pp. 206
Author(s):  
Piconi Corrado ◽  
Sprio Simone
Keyword(s):  
Mechanical Behavior ◽  
Hip Replacement ◽  
Ceramic Composites ◽  
Clinical Applications ◽  
Wide Field ◽  
Joint Replacements ◽  
Composite Systems ◽  
Third Phase ◽  
Main Component ◽  
Zirconia Toughened Alumina

Ceramic composites based on alumina and zirconia have found a wide field of application in the present century in orthopedic joint replacements, and their use in dentistry is spreading. The development of this class of bioceramic composites was started in the 1980s, but the first clinical applications of the total hip replacement joint were introduced in the market only in the early 2000s. Since then, several composite systems were introduced in joint replacements. These materials are classified as Zirconia-Toughened Alumina if alumina is the main component or as Alumina-Toughened Zirconia when zirconia is the main component. In addition, some of them may contain a third phase based on strontium exa-aluminate. The flexibility in device design due to the excellent mechanical behavior of this class of bioceramics results in a number of innovative devices for joint replacements in the hip, the knee, and the shoulder, as well in dental implants. This paper gives an overview of the different materials available and on orthopedic and dental devices made out of oxide bioceramic composites today on the market or under development.

scholarly journals A Multichannel fNIRS System for Prefrontal Mental Task Classification with Dual-level Excitation and Deep Forest Algorithm

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Cheng Chen ◽  
Yizhen Wen ◽  
Shaoyang Cui ◽  
Xiangao Qi ◽  
Zhenhong Liu ◽  
...  
Keyword(s):  
Near Infrared ◽  
Continuous Wave ◽  
Mental Arithmetic ◽  
Digit Span ◽  
Structural Features ◽  
Cortical Activation ◽  
Semantic Task ◽  
High Classification Accuracy ◽  
Task Classification ◽  
Deep Forest

This paper presents a multichannel functional continuous-wave near-infrared spectroscopy (fNIRS) system, which collects data under a dual-level light intensity mode to optimize SNR for channels with multiple source-detector separations. This system is applied to classify different cortical activation states of the prefrontal cortex (PFC). Mental arithmetic, digit span, semantic task, and rest state were selected as four mental tasks. A deep forest algorithm is employed to achieve high classification accuracy. By employing multigrained scanning to fNIRS data, this system can extract the structural features and result in higher performance. The proposed system with proper optimization can achieve 86.9% accuracy on the self-built dataset, which is the highest result compared to the existing systems.

Laser therapy applications for osteoarthritis and chronic joint pain – A randomized placebo-controlled clinical trial

2012 ◽  
Vol 1 (4) ◽  
Author(s):  
Nelson Marquina ◽  
Roger Dumoulin-White ◽  
Arkady Mandel ◽  
Lothar Lilge
Keyword(s):  
Clinical Trial ◽  
Near Infrared ◽  
Continuous Wave ◽  
Laser System ◽  
Laser Diodes ◽  
Average Power ◽  
Evaluation Criteria ◽  
Adjunctive Treatment ◽  
Controlled Clinical Trial ◽  
Primary Evaluation

AbstractA randomized placebo-controlled clinical trial to evaluate an adjunctive treatment modality for pain associated with knee disorders was conducted utilizing a therapeutic laser system (low energy, non-surgical).The therapeutic laser system utilized a dual wavelength, multiple diode laser cluster probe with five super-pulsed 905 nm near-infrared (NIR) laser diodes, each emitting at 40 mW average power and four continuous wave 660 nm visible (VIS) red laser diodes, each emitting at 25 mW. It was used as an adjunctive modality providing 12 treatments, three times a week to a homogeneous patient population (n=126), in combination with standardized chiropractic techniques, to evaluate effectiveness on subjects presenting with osteoarthritis and knee pain. The primary endpoint was measured by the visual analog scale (VAS) to assess pain levels on a scale of 0–10. The success criteria for an individual patient in this study were identified as an improvement of 30% or more in the VAS from baseline to 12th treatment and/or an improvement of 20% or more in the VAS from baseline to 30-day follow-up evaluation.The data obtained in the study demonstrated that the present therapeutic laser system provided significant pain relief and osteoarthritic improvements in all primary evaluation criteria, with a statistical and clinical significance of

Quasi-Continuous Wave Near-Infrared Excitation of Upconversion Nanoparticles for Optogenetic Manipulation ofC. elegans

Small ◽  
2016 ◽  
Vol 12 (13) ◽  
pp. 1732-1743 ◽  
Author(s):  
Akshaya Bansal ◽  
Haichun Liu ◽  
Muthu Kumara Gnanasammandhan Jayakumar ◽  
Stefan Andersson-Engels ◽  
Yong Zhang
Keyword(s):  
Near Infrared ◽  
Continuous Wave ◽  
Upconversion Nanoparticles ◽  
Infrared Excitation
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