{"title":"Photodynamic diagnosis and therapy – How bright is the future?","authors":"S. Bown, H. Stepp","doi":"10.1515/plm-2014-0052","DOIUrl":"https://doi.org/10.1515/plm-2014-0052","url":null,"abstract":"","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"8 1","pages":"1 - 3"},"PeriodicalIF":0.0,"publicationDate":"2015-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79112712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Kleshnin, M. Shirmanova, I. Fiks, A. Orlova, V. Plekhanov, E. Zagainova, S. Lukyanov, I. Turchin
{"title":"Trans-illumination fluorescence imaging of deep-seated tumors in small animals","authors":"M. Kleshnin, M. Shirmanova, I. Fiks, A. Orlova, V. Plekhanov, E. Zagainova, S. Lukyanov, I. Turchin","doi":"10.1515/plm-2014-0024","DOIUrl":"https://doi.org/10.1515/plm-2014-0024","url":null,"abstract":"Abstract Background: Fluorescence diffuse tomography (FDT) is the most accurate technique for the imaging of labeled tumors in the small animal body. However, the procedure for reconstruction of the spatial distribution of the fluorophore requires a high signal-to-noise ratio due to the ill-condition of the inverse problem. Therefore, the FDT technique is ineffective for imaging tumors of small size or with dim fluorophores because of the low intensity of their fluorescence compared with the high level of tissue autofluorescence. In these cases, the size and position of a marked tumor in the animal body can be estimated from two-dimensional fluorescence images obtained using trans- or epi-illumination techniques. Material and methods: A versatile system for small animal fluorescence imaging which combines planar epi- and trans-illumination geometries of the light source and of the fluorescence receiver was created and tested. For epi-illumination imaging, light-emitting diode sources were used to provide homogeneous and stable illumination of the experimental animal, in combination with a cooled CCD camera which covers the entire illuminated area. For trans-illumination imaging, mechanical raster-scanning devices modulated at a low frequency were used for the laser source, together with a cooled photomultiplier tube, which provided outstanding sensitivity. Results: Monitoring the orthotopic tumor growth in animal bodies has demonstrated the efficacy of trans-illumination imaging in comparison with the epi-illumination technique. The results obtained also showed that the effective use of the trans-illumination technique requires Born normalization of the fluorescence signal and the exclusion of lateral illumination by surrounding the animal with additional light absorption material using light-absorption pads on both sides of the body.","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"5 1","pages":"85 - 92"},"PeriodicalIF":0.0,"publicationDate":"2015-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81566981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Timothy C Zhu, Michele M Kim, Xing Liang, Jarod C Finlay, Theresa M Busch
{"title":"<i>In-vivo</i> singlet oxygen threshold doses for PDT.","authors":"Timothy C Zhu, Michele M Kim, Xing Liang, Jarod C Finlay, Theresa M Busch","doi":"10.1515/plm-2014-0037","DOIUrl":"https://doi.org/10.1515/plm-2014-0037","url":null,"abstract":"<p><strong>Objective: </strong>Dosimetry of singlet oxygen (<sup>1</sup>O<sub>2</sub>) is of particular interest because it is the major cytotoxic agent causing biological effects for type-II photosensitizers during photodynamic therapy (PDT). An <i>in-vivo</i> model to determine the singlet oxygen threshold dose, [<sup>1</sup>O<sub>2</sub>]<sub>rx,sh</sub>, for PDT was developed.</p><p><strong>Material and methods: </strong>An <i>in-vivo</i> radiation-induced fibrosarcoma (RIF) tumor mouse model was used to correlate the radius of necrosis to the calculation based on explicit PDT dosimetry of light fluence distribution, tissue optical properties, and photosensitizer concentrations. Inputs to the model include five photosensitizer-specific photochemical parameters along with [<sup>1</sup>O<sub>2</sub>]<sub>rx,sh</sub>. Photosensitizer-specific model parameters were determined for benzoporphyrin derivative monoacid ring A (BPD) and compared with two other type-II photosensitizers, Photofrin<sup>®</sup> and m-tetrahydroxyphenylchlorin (mTHPC) from the literature.</p><p><strong>Results: </strong>The mean values (standard deviation) of the <i>in-vivo</i> [<sup>1</sup>O<sub>2</sub>]<sub>rx,sh</sub> are approximately 0.56 (0.26) and 0.72 (0.21) mM (or 3.6×10<sup>7</sup> and 4.6×10<sup>7</sup> singlet oxygen per cell to reduce the cell survival to 1/e) for Photofrin<sup>®</sup> and BPD, respectively, assuming that the fraction of generated singlet oxygen that interacts with the cell is 1. While the values for the photochemical parameters (ξ, σ, <i>g</i>, β) used for BPD were preliminary and may need further refinement, there is reasonable confidence for the values of the singlet oxygen threshold doses.</p><p><strong>Discussion: </strong>In comparison, the [<sup>1</sup>O<sub>2</sub>]<sub>rx,sh</sub> value derived from <i>in-vivo</i> mouse study was reported to be 0.4 mM for mTHPC-PDT. However, the singlet oxygen required per cell is reported to be 9×10<sup>8</sup> per cell per 1/<i>e</i> fractional kill in an <i>in-vitro</i> mTHPC-PDT study on a rat prostate cancer cell line (MLL cells) and is reported to be 7.9 mM for a multicell <i>in-vitro</i> EMT6/Ro spheroid model for mTHPC-PDT. A theoretical analysis is provided to relate the number of <i>in-vitro</i> singlet oxygen required per cell to reach cell killing of 1/<i>e</i> to <i>in-vivo</i> singlet oxygen threshold dose (in mM). The sensitivity of threshold singlet oxygen dose for our experiment is examined. The possible influence of vascular vs. apoptotic cell killing mechanisms on the singlet oxygen threshold dose is discussed by comparing [<sup>1</sup>O<sub>2</sub>]<sub>rx,sh</sub> for BPD with 3 hr and 15 min drug-light-intervals, with the later being known to have a dominantly vascular effect.</p><p><strong>Conclusions: </strong>The experimental results of threshold singlet oxygen concentration in an <i>in-vivo</i> RIF tumor model for Photofrin<sup>®</sup>, BPD, and mTHPC are about 20 times smalle","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"4 1","pages":"59-71"},"PeriodicalIF":0.0,"publicationDate":"2015-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/plm-2014-0037","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33263017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Davoudi, D. Gasumova, K. Bizheva, R. Dinniwell, W. Levin, I. Vitkin
{"title":"Quantitative assessment of oral microstructural and microvascular changes in late oral radiation toxicity, using noninvasive in-vivo optical coherence tomography","authors":"B. Davoudi, D. Gasumova, K. Bizheva, R. Dinniwell, W. Levin, I. Vitkin","doi":"10.1515/plm-2015-0025","DOIUrl":"https://doi.org/10.1515/plm-2015-0025","url":null,"abstract":"Abstract Background and objectives: About half of the head and neck cancer patients treated with radiotherapy suffer from late radiation effects months to years after the treatment. The most common diagnosis and monitoring methods for such oral toxicities are based on surface examination of the oral tissue, which is subjective. Therefore, subsurface imaging and image quantification tools can be highly useful for monitoring these late effects as these approaches are more robust and objective. In this study, we demonstrate the ability of optical coherence tomography (OCT) technology and its newly developed quantitative imaging platform to reveal subsurface microstructural and microvascular changes in late oral radiation toxicity patients, not detectable by available clinical tools. Materials and methods: Fifteen patients exhibiting late oral radiation toxicity, and five healthy age-matched volunteers were imaged with OCT in a clinical pilot study. Image assessment methods, developed in-house, were used to extract four quantitative metrics of potential clinical importance from the acquired microstructural and microvascular oral OCT images. Results: The statistically significant differences in the patients compared to healthy volunteers were: lower epithelium to lamina propria thickness (indicating epithelial atrophy and/or fibrosis of lamina propria), smaller vessel diameter (indicating vessel lumen narrowing), and higher blood velocity. The observed in-vivo morphological changes correlated well with reported histology findings. No significant changes were observed in vessel tortuosity between the cohorts. Conclusion: The quantitative metrics extracted from the OCT images demonstrated significant microstructural and microvascular differences between the two cohorts. Potentially, OCT and its newly developed image analysis platform can be used as a noninvasive in-vivo subsurface tool for “shedding light” on late oral radiation toxicity, for example in palliative treatment efficacy monitoring.","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"23 1","pages":"21 - 32"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78580990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Protokoll der Mitgliederversammlung der Deutschen Gesellschaft für Lasermedizin (DGLM) e.V.","authors":"C. Philipp, R. Sroka","doi":"10.1515/plm-2014-0039","DOIUrl":"https://doi.org/10.1515/plm-2014-0039","url":null,"abstract":"","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"42 4","pages":"389 - 392"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91399755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of CO2 laser efficacy in the treatment of cutaneous leishmaniasis in a group of 10 Sudanese patients","authors":"A. Osman, N. Almuslet","doi":"10.1515/plm-2015-0008","DOIUrl":"https://doi.org/10.1515/plm-2015-0008","url":null,"abstract":"Abstract Background and objective: Cutaneous leishmaniasis (CL) is a protozoal skin disease, transmitted by the bite of an infected female sand fly. The result of infection can vary from a chronic skin ulcer to erosive mucosal disease. The disease is endemic in Sudan, persists for longer periods and heals with disfiguring scars. The use of lasers has not been extensively tried out in the treatment of this disease. The present case study aimed to evaluate the efficacy of a fractional CO2 laser treatment in a group of Sudanese patients suffering from CL. Patients and methods: The ulcers of 10 randomly selected Sudanese patients, diagnosed as CL patients, were ablated using a 10,600 nm CO2 laser in fractional mode with a power density of up to 2 W/cm2. The reaction of the patients was observed and their response to the treatment was evaluated 1, 2 and 4 weeks after the laser session. Lesions were photographed and rated by the patient him/herself and an independent blinded evaluator. Results: The majority of the patients (8 out of 10) had either a complete or very good improvement by the end of follow-up. Pain occurred post-operatively in all patients, while edema, infection and hypo/hyperpigmentation occurred in only two patients. These side effects were trivial and disappeared a few days after treatment. Conclusion: The fractional CO2 laser can be used as a good modality for the treatment of CL ulcers.","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"20 1","pages":"259 - 263"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89357532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Biophotonics symposium – A scientific cruise","authors":"M. Kirillin, N. Shakhova, I. Turchin","doi":"10.1515/plm-2014-0038","DOIUrl":"https://doi.org/10.1515/plm-2014-0038","url":null,"abstract":"","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"30 1 1","pages":"283 - 285"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80947816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Jaeger, Kujtim Gashi, H. G. Akarçay, G. Held, S. Peeters, T. Petrosyan, Stefan Preisser, Michael Gruenig, M. Frenz
{"title":"Real-time clinical clutter reduction in combined epi-optoacoustic and ultrasound imaging","authors":"M. Jaeger, Kujtim Gashi, H. G. Akarçay, G. Held, S. Peeters, T. Petrosyan, Stefan Preisser, Michael Gruenig, M. Frenz","doi":"10.1515/plm-2014-0028","DOIUrl":"https://doi.org/10.1515/plm-2014-0028","url":null,"abstract":"Abstract Flexible imaging of the human body, a requirement for broad clinical application, is obtained by direct integration of optoacoustic (OA) imaging with echo ultrasound (US) in a multimodal epi-illumination system. Up to date, successful deep epi-OA imaging is difficult to achieve owing to clutter. Clutter signals arise from optical absorption in the region of tissue irradiation and strongly reduce contrast and imaging depth. Recently, we developed a displacement-compensated averaging (DCA) technique for clutter reduction based on the clutter decorrelation that occurs when palpating the tissue. To gain first clinical experience on the practical value of DCA, we implemented this technique in a combined clinical OA and US imaging system. Our experience with freehand scanning of human volunteers reveals that real-time feedback on the clutter-reduction outcome is a key factor for achieving superior contrast and imaging depth.","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"9 1","pages":"343 - 349"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85427705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Vaks, E. Domracheva, E. Sobakinskaya, M. Chernyaeva
{"title":"High-precision terahertz spectroscopy for noninvasive medicine diagnostics","authors":"V. Vaks, E. Domracheva, E. Sobakinskaya, M. Chernyaeva","doi":"10.1515/plm-2014-0026","DOIUrl":"https://doi.org/10.1515/plm-2014-0026","url":null,"abstract":"Abstract In recent years methods for exhaled breath analysis have been developing all around the world. The exhaled breath analysis could result in a powerful tool for noninvasive medicine. The work presented in this paper is concerned with gas analyzers for exhaled breath diagnostics. The analyzers are based on high-precision spectrometers of the THz frequency range, which provide high resolution, high sensitivity and detect a wide range of detectable substances. The spectrometers work on non-stationary effects (phase-switching and fast sweep of frequency). The analyzers have been successfully applied for the detection of various biomarkers (nitric oxide, acetone, ammonia, methanol, ethanol) in the breath of conditionally healthy volunteers and patients with various cancerous and noncancerous diseases.","PeriodicalId":20126,"journal":{"name":"Photonics & Lasers in Medicine","volume":"56 1","pages":"373 - 380"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82841020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}