1
|
Sheet AH, Hamdy O, Abdel-Harith M. Scattering and absorption properties modification of optically cleared skeletal muscles: an ex vivo study. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2023; 40:1042-1050. [PMID: 37706757 DOI: 10.1364/josaa.486496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/12/2023] [Indexed: 09/15/2023]
Abstract
Optical clearing is a relatively new approach to enhancing the optical transparency of biological tissues by reducing their scattering properties. The optical clearing effect is achievable via various chemical, physical, and photo-thermal techniques. The present work studied optical parameters of bovine skeletal muscles under different clearing protocols: immersion optical clearing in 99% glycerol and photo-thermal optical clearing via exposure to IR laser irradiation. Moreover, the two techniques were combined with different immersion time intervals after multiple exposure periods to get optimum results. The muscle samples' diffuse reflectance and total transmittance were measured using a single integrating sphere and introduced to the Kubleka-Munk mathematical model to determine the absorption and reduced scattering coefficients. Results revealed a 6% scattering reduction after irradiating the sample for 10 min and immersing it in glycerol for 18 min and 8% after 20 min of laser irradiation and 18 min of immersion. Moreover, increases of 6.5% and 7.5% in penetration depth were prominent for the total treatment times of 28 min and 38 min, respectively. Furthermore, the measurements' accuracy and sensitivity were analyzed and evaluated using the receiver operating characteristic method. The accuracy ranged from 0.93 to 0.98, with sensitivity from 0.93 to 0.99 for each clearing protocol. Although laser irradiation and application of 99% glycerol separately produced scattering light reduction, the maximal clearing effect was obtained while irradiating the sample with a laser for 20 min and then immersing it in 99% glycerol for a maximum of 18 min.
Collapse
|
2
|
Hassan NI, Hassan YM, Mustafa TA, Hamdy O. Modeling optical fluence and diffuse reflectance distribution in normal and cancerous breast tissues exposed to planar and Gaussian NIR beam shapes using Monte Carlo simulation. Lasers Med Sci 2023; 38:96. [PMID: 37004565 DOI: 10.1007/s10103-023-03758-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 03/28/2023] [Indexed: 04/04/2023]
Abstract
Precise knowledge about light propagation in biological tissues is necessary for accurate diagnostics and effective therapies utilizing optical technologies. In the current paper, the Monte Carlo simulation is applied to study light dispersion in normal and cancerous breast after irradiating to different laser beam shapes. Two distinct laser wavelengths (800-1100 nm) with planar and Gaussian shapes were employed. The spatially resolved steady-state diffuse reflectance of normal tissue and tumor was investigated using Monte Carlo simulation method via MCML and MCXLAB computations. The diffusion equation was solved to simulate the fluence rate at the tissue surface based on the optical parameter values (i.e., scattering and absorption coefficients). The results confirm differences in diffuse reflectance and optical fluence distribution between the normal and tumor tissues at each wavelength. Tissue optical parameters and the utilized laser beam shape control the distribution of the fluence rate within tissues. Therefore, offering visual representations of these distributions can provide a secure visual route for biological diagnostics.
Collapse
Affiliation(s)
| | | | - Twana Ahmad Mustafa
- Hawler Health and Medical Technical Collage, Erbil Polytechnic University, Erbil, Iraq
| | - Omnia Hamdy
- National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt
| |
Collapse
|
3
|
Mahdy S, Hamdy O, Eldosoky MAA, Hassan MA. Influence of Tumor Volume on the Fluence Rate Within Human Breast Model Using Continuous-Wave Diffuse Optical Imaging: A Simulation Study. Photobiomodul Photomed Laser Surg 2023; 41:125-132. [PMID: 36927048 DOI: 10.1089/photob.2022.0100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
Objective: This article investigates the effect of varying breast tumor size on the fluence rate distribution within a breast model during the diffuse optical imaging procedure. Background: Early detection of breast cancer is of significant importance owing to its wide spread among women worldwide. Mastectomy surgery became very common due to the late detection of breast cancers by the conventional diagnostic methods such as X-ray mammography and magnetic resonance imaging. On the contrary, optical imaging techniques provide a safe and more sensitive methodology, which is suitable for the early detection criteria. Methods: The implementation was performed based on simulating multiple detectors placed on the outer surface of a human breast model to compute the optical fluence rate after probing the breast (normal and different tumor sizes) with laser irradiation. Different laser wavelengths ranging from the red to near-infrared rays spectral range were examined to determine the optimum fluence rate that shows the highest capability to differentiate between normal and cancerous breasts. A three-dimensional breast model was created using the COMSOL multiphysics package where the optical fluence rate was estimated based on the finite-element solution of the diffusion equation. Results: To evaluate the efficiency of the suggested technique for identifying cancers and discriminate them from normal breast at various wavelengths (600-1000 nm) and several tumor sizes. Conclusions: The obtained results reveal different fluence rate distributions in the breast with different radius tumors, especially at 600 nm due to the significant differences in the scattering coefficient between malignancies and healthy tissue.
Collapse
Affiliation(s)
- Shimaa Mahdy
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt.,Department of Electrical Engineering, Egyptian Academy for Engineering and Advanced Technology (EAE&AT), Affiliated to Ministry of Military Production, Cairo, Egypt
| | - Omnia Hamdy
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences, Cairo University, Giza, Egypt
| | - Mohamed A A Eldosoky
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt
| | - Mohammed A Hassan
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt
| |
Collapse
|
4
|
Abuelmakarem HS, Hamdy O, Sliem MA, El-Azab J, Ahmed WA. Early cancer detection using the fluorescent Ashwagandha chitosan nanoparticles combined with near-infrared light diffusion characterization: in vitro study. Lasers Med Sci 2023; 38:37. [PMID: 36627516 PMCID: PMC9832086 DOI: 10.1007/s10103-022-03678-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 10/18/2022] [Indexed: 01/12/2023]
Abstract
Early cancer diagnosis through characterizing light propagation and nanotechnology increases the survival rate. The present research is aimed at evaluating the consequence of using natural nanoparticles in cancer therapy and diagnosis. Colon cancer cells were differentiated from the normal cells via investigating light diffusion combined with the fluorescence effect of the Ashwagandha chitosan nanoparticles (Ash C NPs). Ionic gelation technique synthesized the Ash C NPs. High-resolution transmission electron microscope, dynamic light scattering, and zeta potential characterized Ash C NPs. Fourier transform infrared spectroscopy analyzed Ash C NPs, chitosan, and Ashwagandha root water extract. Moreover, the MTT assay evaluated the cytotoxicity of Ash C NPs under the action of near-infrared light (NIR) irradiation. The MTT assay outcomes were statistically analyzed by Bonferroni post hoc multiple two-group comparisons using one-way variance analysis (ANOVA). Based on the Monte-Carlo simulation technique, the spatially resolved steady-state diffusely reflected light from the cancerous and healthy cells is acquired. The diffuse equation reconstructed the optical fluence rate using the finite element technique. The fluorescent effect of the nanoparticles was observed when the cells were irradiated with NIR. The MTT assay revealed a decrease in the cell viability under the action of Ash C NPs with and without laser irradiation. Colon cancer and normal cells were differentiated based on the optical characterization after laser irradiation. The light diffusion equation was successfully resolved for the fluence rate on cells' surfaces showing different normal and cancer cells values. Ash C NPs appeared its fluorescent effect in the presence of NIR laser.
Collapse
Affiliation(s)
- Hala S Abuelmakarem
- System and Biomedical Engineering Department, The Higher Institute of Engineering, El Shoruk Academy, El-Shorouk, Egypt.
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Giza Governorate, Giza, 12613, Egypt.
| | - Omnia Hamdy
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Giza Governorate, Giza, 12613, Egypt
| | - Mahmoud A Sliem
- Department of Laser Applications in Metrology, Photochemistry and Agriculture (LAMPA), National Institute of Laser Enhanced Sciences (NILE), Cairo University, Giza, 12613, Egypt
- Chemistry Department, Faculty of Science, Taibah University, Al-Ula, Medina, Saudi Arabia
| | - Jala El-Azab
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Giza Governorate, Giza, 12613, Egypt
| | - Wafaa A Ahmed
- Cancer Biology Department, Biochemistry and Molecular Biology Unit, National Cancer Institute, Cairo University, Giza, Egypt
| |
Collapse
|
5
|
Optical Characterization of Biological Tissues Based on Fluorescence, Absorption, and Scattering Properties. Diagnostics (Basel) 2022; 12:diagnostics12112846. [PMID: 36428905 PMCID: PMC9689259 DOI: 10.3390/diagnostics12112846] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/09/2022] [Accepted: 11/16/2022] [Indexed: 11/19/2022] Open
Abstract
Optical diagnostics methods are significantly appealing in biological applications since they are non-destructive, safe, and minimally invasive. Laser-induced fluorescence is a promising optical spectrochemical analytical technique widely employed for tissue classification through molecular analysis of the studied samples after excitation with appropriate short-wavelength laser light. On the other hand, diffuse optics techniques are used for tissue monitoring and differentiation based on their absorption and scattering characteristics in the red to the near-infrared spectra. Therefore, it is strongly foreseen to obtain promising results by combining these techniques. In the present work, tissues under different conditions (hydrated/dry skin and native/boiled adipose fat) were distinguished according to their fluorescence emission, absorption, and scattering properties. The selected tissues' optical absorption and scattering parameters were determined via Kubelka-Munk mathematical model according to the experimental tissue reflectance and transmittance measurements. Such measurements were obtained using an optical configuration of integrating sphere and spectrometer at different laser wavelengths (808, 830, and 980 nm). Moreover, the diffusion equation was solved for the fluence rate at the sample surface using the finite element method. Furthermore, the accuracy of the obtained spectroscopic measurements was evaluated using partial least squares regression statistical analysis with 0.87 and 0.89 R-squared values for skin and adipose fat, respectively.
Collapse
|
6
|
Halim ASA, Mostafa M, Hamdy O. Miniaturized antenna verified with diffuse optical measurements for native and boiled adipose tissue differentiation. Sci Rep 2022; 12:15035. [PMID: 36057671 PMCID: PMC9440913 DOI: 10.1038/s41598-022-19430-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 08/29/2022] [Indexed: 12/03/2022] Open
Abstract
Medical industries are continuously working towards the development of wearable theragnostic devices which enable monitoring various ailments in the body and then transmitting them to the base-station. The antenna design is of prime importance where the suitable design guarantees proper communication between the antenna and the base-station. In this paper, a co-planar wave-guide antenna is proposed for the use in the medical implant communication service (MICS) band for data transmission. The proposed antenna is studied for ex-vivo applications where the antenna is simulated for bovine intramuscular fat (adipose tissue). The preliminary results showed that the antenna radiates in MICS band. Two types of samples are tested; namely, native fat and boiled fat. The boiled fat is used in order to represent the infected fat tissue. Hence, the antenna was implanted into the fat samples and the results revealed noticeable variations in the radiation characteristics between native and boiled fat. Different parameters of the proposed antenna including the reflection coefficient (S11), radiation patterns, gain, efficiency, and front-to-back ratio are investigated. The simulations showed that S11 parameter was − 12.4 dB in MICS band for the normal fat. On the other hand, the measured S11 values were − 12.3 dB for the native samples and − 9.9 dB for the boiled fat samples. To assert the variation in the biological characteristics of the boiled fat as compared to those of the native fat, diffuse optical measurements of the examined samples were investigated. Such variation in the light scattering and absorbance by the tissue is responsible for varying the S11 parameter for each case. The results have shown that the proposed design is a good candidate for detecting the change in biological tissue.
Collapse
Affiliation(s)
- Ashraf S Abdel Halim
- Department of Communication, Faculty of Engineering, Canadian International College (CIC), Cairo, Egypt
| | - Mohanad Mostafa
- Department of Communication, Faculty of Engineering, Canadian International College (CIC), Cairo, Egypt
| | - Omnia Hamdy
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences, Cairo University, Giza, Egypt.
| |
Collapse
|
7
|
Shanshool AS, Lazareva EN, Hamdy O, Tuchin VV. Optical Properties and Fluence Distribution in Rabbit Head Tissues at Selected Laser Wavelengths. MATERIALS (BASEL, SWITZERLAND) 2022; 15:5696. [PMID: 36013828 PMCID: PMC9413642 DOI: 10.3390/ma15165696] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/11/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
The accurate estimation of skin and skull optical properties over a wide wavelength range of laser radiation has great importance in optogenetics and other related applications. In the present work, using the Kubelka-Munk model, finite-element solution of the diffusion equation, inverse adding-doubling (IAD), and Monte-Carlo simulation, we estimated the refractive index, absorption and scattering coefficients, penetration depth, and the optical fluence distribution in rabbit head tissues ex vivo, after dividing the heads into three types of tissues with an average thickness of skin of 1.1 mm, skull of 1 mm, and brain of 3 mm. The total diffuse reflectance and transmittance were measured using a single integrating sphere optical setup for laser radiation of 532, 660, 785, and 980 nm. The calculated optical properties were then applied to the diffusion equation to compute the optical fluence rate distribution at the boundary of the samples using the finite element method. Monte-Carlo simulation was implemented for estimating the optical fluence distribution through a model containing the three tissue layers. The scattering coefficient decreased at longer wavelengths, leading to an increase in optical fluence inside the tissue samples, indicating a higher penetration depth, especially at 980 nm. In general, the obtained results show good agreement with relevant literature.
Collapse
Affiliation(s)
| | - Ekaterina Nikolaevna Lazareva
- Science Medical Center, Saratov State University, 410012 Saratov, Russia
- Laboratory of Laser Molecular Imaging and Machine Learning, Tomsk State University, 634050 Tomsk, Russia
| | - Omnia Hamdy
- Department of Engineering Applications of Laser, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Giza 12613, Egypt
| | - Valery Victorovich Tuchin
- Science Medical Center, Saratov State University, 410012 Saratov, Russia
- Laboratory of Laser Molecular Imaging and Machine Learning, Tomsk State University, 634050 Tomsk, Russia
- Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control, FRC “Saratov Scientific Centre of the Russian Academy of Sciences”, 410028 Saratov, Russia
| |
Collapse
|
8
|
Mahdy S, Hamdy O, Hassan MA, Eldosoky MAA. A modified source-detector configuration for the discrimination between normal and diseased human breast based on the continuous-wave diffuse optical imaging approach: a simulation study. Lasers Med Sci 2022; 37:1855-1864. [PMID: 34651256 DOI: 10.1007/s10103-021-03440-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 10/06/2021] [Indexed: 11/29/2022]
Abstract
Breast tumors are among the most common types of tumors that can affect both genders. It may spread to the whole breast without any symptoms. Therefore, the early detection and accurate diagnosis of breast tumors are significantly important. Current approaches for breast cancer screening such as positron emission tomography (PET) and magnetic resonance imaging (MRI) have some limitations of being time and money-consuming. In addition, mammography screening is not recommended for women under forty. Consequently, optical techniques have been introduced as safe and functional alternatives. Diffuse optical imaging is a non-invasive imaging technique that utilizes near-infrared light to examine biological tissues based on measuring the optical transmission and/or reflection at various locations on the tissue surface. In this paper, we propose a modified arrangement between the laser source and the detectors for distinguishing tumors from normal breast tissue. A three-dimensional model of the normal human breast with three types of tumors is developed using a COMSOL simulation software based on the finite element solution of Helmholtz equation to estimate optical fluence distribution. The breast model consists of four layers: skin, fat, glandular, and muscle, where the tumor is included in the glandular layer. Different wavelengths were used to determine the most proper wavelength for the discrimination between the normal tissue and tumor. The obtained results were verified using the receiver operating characteristic (ROC) method. The resultant fluence images show different features between normal breast and breast with tumor especially using 600-nm incident laser as demonstrated by the obtained ROC curves.
Collapse
Affiliation(s)
- Shimaa Mahdy
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt
- Department of Electrical Engineering, Egyptian Academy for Engineering and Advanced Technology (EAE&AT) Affiliated to Ministry of Military Production, Cairo, Egypt
| | - Omnia Hamdy
- Department of Engineering Applications of Lasers, National Institute of Laser Enhanced Sciences, Cairo University, Giza, Egypt.
| | - Mohammed A Hassan
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt
| | - Mohamed A A Eldosoky
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Cairo, Egypt
| |
Collapse
|
9
|
Hamdy O, Mohammed HS. Variations in tissue optical parameters with the incident power of an infrared laser. PLoS One 2022; 17:e0263164. [PMID: 35100314 PMCID: PMC8803203 DOI: 10.1371/journal.pone.0263164] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/12/2022] [Indexed: 11/18/2022] Open
Abstract
Infrared (IR) lasers are extensively utilized as an effective tool in many medical practices. Nevertheless, light penetration into the inspected tissue, which is highly affected by tissue optical properties, is a crucial factor for successful optical procedures. Although the optical properties are highly wavelength-dependent, they can be affected by the power of the incident laser. The present study demonstrates a considerable change in the scattering and absorption coefficients as a result of varying the incident laser power probing into biological samples at a constant laser wavelength (808 nm). The optical parameters were investigated using an integrating sphere and Kubelka-Munk model. Additionally, fluence distribution at the sample's surface was modeled using COMSOL-multiphysics software. The experimental results were validated using Receiver Operating Characteristic (ROC) curves and Monte-Carlo simulation. The results showed that tissue scattering coefficient decreases as the incident laser power increases while the absorption coefficient experienced a slight change. Moreover, the penetration depth increases with the optical parameters. The reduction in the scattering coefficients leads to wider and more diffusive fluence rate distribution at the tissue surface. The simulation results showed a good agreement with the experimental data and revealed that tissue anisotropy may be responsible for this scattering reduction. The present findings could be considered in order for the specialists to accurately specify the laser optical dose in various biomedical applications.
Collapse
Affiliation(s)
- Omnia Hamdy
- Engineering Applications of Lasers Department, National Institute of Laser Enhanced Sciences, Cairo University, Giza, Egypt
| | | |
Collapse
|
10
|
Utilization of Spectrochemical Analysis and Diffuse Optical Techniques to Reveal Adulteration of Alike Fish Species and Their Microbial Contamination. FOOD ANAL METHOD 2022. [DOI: 10.1007/s12161-021-02212-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
11
|
Dependence of the heating effect on tissue absorption coefficient during corneal reshaping using different UV lasers: A numerical study. Phys Eng Sci Med 2021; 44:221-227. [PMID: 33475960 DOI: 10.1007/s13246-021-00971-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/05/2021] [Indexed: 10/22/2022]
Abstract
Corneal reshaping using laser ablation effect is a well-known ophthalmologic operation implemented to correct many vision disorders. UV pulsed lasers are utilized in this surgery due to their high absorption in corneal tissue without affecting the other parts of the eye. Ideally ablation may not be associated with heat transport, since high temperature is the enemy of soft tissues. However, the thermal effect of this procedure can cause tissue damage if the temperature rises above the safety level without appropriate handling. In the present study, we try to find the trade-off between efficient ablation and minimal temperature rise. So the thermal effect on the corneal tissue after applying five UV wavelengths; 193, 210, 213, 223 and 248 nm has been simulated and investigated by solving Penne's bio-heat transfer equation using the finite element method. A 3D model of the human cornea is constructed using COMSOL Multiphysics computer software and the temperature rise is determined at the end of the laser pulse. The same spot size and pulse duration are used for each wavelength. While the absorption coefficient of the corneal tissue is the only variable as it is a wavelength dependent. The proposed results show that, the heating effect is directly proportional to the absorption coefficient. The highest recorded temperature was 259 °C at 193 nm, while, the minimum value was (70.1 °C) recorded at 248 nm at which the cornea has the lowest absorption coefficient.
Collapse
|
12
|
Hamdy O, Mohammed HS. Investigating the transmission profiles of 808 nm laser through different regions of the rat's head. Lasers Med Sci 2020; 36:803-810. [PMID: 32638241 DOI: 10.1007/s10103-020-03098-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/01/2020] [Indexed: 11/30/2022]
Abstract
Studying light penetration in biological tissues became a very important concern in various medical applications. It is an essential factor required to resolve the optical dose in many diagnostic and therapeutic procedures. The absorption and scattering properties of the inspected tissue control how deep the light will travel inside the tissue. However, these optical properties are highly dependent on the wavelength of the light source. In this work, the light transmission through different regions of the rat's head was investigated and the minimum laser power required to reach different parts of the head is also determined using 808-nm semiconductor laser diode. The power variation in different regions of the head is estimated using Monte Carlo simulation. Absorption and scattering coefficients of the head layers were calculated using integrating sphere measurements and Kubelka-Munk model. The absorption coefficient of the skin was 0.19 ± 0.071 mm-1, 0.024 ± 0.11 mm-1 for skull, and 0.35 ± 0.13 mm-1 for the brain, while the scattering coefficients were 7.35 ± 1.09, 2.71 ± 0.37, and 13.04 ± 0.36 mm-1 for skin, skull, and brain, respectively. The obtained results provide a relationship between laser incident power and the depth in the rat's head showing a higher optical transmission at the frontal part of the head than the middle or back regions due to the variations in the skull thickness. Therefore, the study revealed that the transmitted power of 808 nm laser at different incident locations on the head is nonlinear and variable due to different skull's thickness.
Collapse
Affiliation(s)
- Omnia Hamdy
- Department Of Engineering Applications of Laser, The National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt.
| | - Haitham S Mohammed
- Biophysics Department, Faculty of Science, Cairo University, Giza, 12613, Egypt
| |
Collapse
|
13
|
Huang X, Protheroe MD, Al-Jumaily AM, Paul SP, Chalmers AN. Review of human hair optical properties in possible relation to melanoma development. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 29752798 DOI: 10.1117/1.jbo.23.5.050901] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
Immigration and epidemiological studies provide evidence indicating the correlation of high ultraviolet exposure during childhood and increased risks of melanoma in later life. While the explanation of this phenomenon has not been found in the skin, a class of hair has been hypothesized to be involved in this process by transmitting sufficient ultraviolet rays along the hair shaft to possibly cause damage to the stem cells in the hair follicle, ultimately resulting in melanoma in later life. First, the anatomy of hair and its possible contribution to melanoma development, and the tissue optical properties are briefly introduced to provide the necessary background. This paper emphasizes on the review of the experimental studies of the optical properties of human hair, which include the sample preparation, measurement techniques, results, and statistical analysis. The Monte Carlo photon simulation of human hair is next outlined. Finally, current knowledge of the optical studies of hair is discussed in the light of their possible contribution to melanoma development; the necessary future work needed to support this hypothesis is suggested.
Collapse
Affiliation(s)
- Xiyong Huang
- Auckland University of Technology, Institute of Biomedical Technologies, Auckland, New Zealand
| | - Michael D Protheroe
- Auckland University of Technology, Institute of Biomedical Technologies, Auckland, New Zealand
| | - Ahmed M Al-Jumaily
- Auckland University of Technology, Institute of Biomedical Technologies, Auckland, New Zealand
| | - Sharad P Paul
- Auckland University, Faculty of Surgery, Auckland, New Zealand
| | - Andrew N Chalmers
- Auckland University of Technology, Institute of Biomedical Technologies, Auckland, New Zealand
| |
Collapse
|