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Objective To explore the application of ALA photodynamic fluorescence combined with dermatoscopy in the diagnosis of facial cancerization and precancerous lesions. Methods From March 2022 to March 2024, a total of 52 patients with actinic keratosis, BOWEN's disease, squamous cell carcinoma and basal cell carcinoma were enrolled at the dermatology clinic of the First Affiliated Hospital of Henan University of Science and Technology. Each patient was examined by naked eye and ALA photodynamic fluorescence, and the difference in area was compared between these two methods. The ALA photodynamic fluorescence area was divided into 8 equal sections, followed by examination with a dermatoscope to determine whether there were cancerization and precancerous lesions. The lesion area and severity were scored. Results The ALA photodynamic fluorescence area was larger than that observed by the naked eye (all P<0.001). Dermatoscopic examination of the ALA photodynamic fluorescence imaging area revealed precancerous features of various areas and severity, with cancerous area and severity scores of 4.55±1.21, 5.45±2.42, 6.64±2.84, and 5.27±1.95, respectively. Conclusions ALA-photodynamic fluorescence combined with dermatoscopy can find cancerization and precancerous lesions that can't be detected by naked eyes, providing a new method for early screening and early diagnosis of skin cancerization and precancerous lesions. [ABSTRACT FROM AUTHOR]

Objective To explore the application of ALA photodynamic fluorescence combined with dermatoscopy in the diagnosis of facial cancerization and precancerous lesions. Methods From March 2022 to March 2024, a total of 52 patients with actinic keratosis, BOWEN's disease, squamous cell carcinoma and basal cell carcinoma were enrolled at the dermatology clinic of the First Affiliated Hospital of Henan University of Science and Technology. Each patient was examined by naked eye and ALA photodynamic fluorescence, and the difference in area was compared between these two methods. The ALA photodynamic fluorescence area was divided into 8 equal sections, followed by examination with a dermatoscope to determine whether there were cancerization and precancerous lesions. The lesion area and severity were scored. Results The ALA photodynamic fluorescence area was larger than that observed by the naked eye (all P

Background: Difficulties in the treatment of purulent wounds are caused by bacterial biofilms, which results in decontamination limitations. Infected wounds are not sufficiently susceptible to existing antibiotics, necessitating the search for alternative approaches to reduce the concentration of pathogenic microflora. Methods: This study describes an approach to the effective treatment of wounds by photodynamic inactivation or therapy (PDI/PDT) of antibiotic-resistant microflora under fluorescence control. For this purpose, laser and LED light (660–680 nm) and different groups of photosensitizers (PS) (1% solutions of methylene blue, aluminum phthalocyanine, chlorine e6 and nanocomposites containing these groups of PS) were used. The study included 90 patients with various wounds. Some patients were subjected to fluorescence diagnosis by laser spectral analysis before the PDT. Results: Positive results were achieved in 76 patients (84%, p < 0.05). After the first PDT session, a decrease in the concentration of microflora was noticeable. By the third and seventh days, a significant to complete inactivation of bacteria was obtained. In all patients who were photo-diagnosed before PDT, a significant PS concentration decrease of more than 75% after PDT was obtained. Conclusion: PDT is an effective method for the inactivation of antibiotic-resistant pathogens, including in long non-healing wounds, contributing also to early tissue regeneration. [ABSTRACT FROM AUTHOR]

The purpose of the work is to follow the dynamics of changes in fluorescent signals in the near-surface layers of tissue of injured areas of the back of laboratory animals, which will allow, by indirect evidence, to evaluate the information content of fluorescence diagnosis for subsequent possible diagnostic monitoring of photodynamic therapy of the spinal cord. The model animals were Wistar rats. Two types of contusions were modeled: pneumo-contusion and contusion by a falling load. Methylene blue and indocyanine green were used as photosensitizers. Fluorescence measurements were carried out by imaging and spectrometric methods. A stroboscopic fluorescence imager with an excitation wavelength of 630 nm was used to acquire fluorescence images. The LESA-01-BIOSPEC spectrometer with a He-Ne laser excitation allowed to obtain spectra. It was shown that both methods make it possible to estimate the fluorescence value of methylene blue and indocyanine green in the tissues under study. Moreover, the photographic method also allows to obtain the spatial distribution of fluorescence. The general trend found in the data is a more intense and uniform fluorescence of the dorsal region of rats with methylene blue and a less intense, but more contrasting distribution of indocyanine green. The presented methods are non-invasive, which makes them attractive for diagnostic use. However, due to the shallow depth of signal reception, the condition of the spine can be determined only indirectly, by the condition of the near-surface layers of tissue that accumulate the photosensitizer.

Background: Difficulties in the treatment of purulent wounds are caused by bacterial biofilms, which results in decontamination limitations. Infected wounds are not sufficiently susceptible to existing antibiotics, necessitating the search for alternative approaches to reduce the concentration of pathogenic microflora. Methods: This study describes an approach to the effective treatment of wounds by photodynamic inactivation or therapy (PDI/PDT) of antibiotic-resistant microflora under fluorescence control. For this purpose, laser and LED light (660–680 nm) and different groups of photosensitizers (PS) (1% solutions of methylene blue, aluminum phthalocyanine, chlorine e6 and nanocomposites containing these groups of PS) were used. The study included 90 patients with various wounds. Some patients were subjected to fluorescence diagnosis by laser spectral analysis before the PDT. Results: Positive results were achieved in 76 patients (84%, p < 0.05). After the first PDT session, a decrease in the concentration of microflora was noticeable. By the third and seventh days, a significant to complete inactivation of bacteria was obtained. In all patients who were photo-diagnosed before PDT, a significant PS concentration decrease of more than 75% after PDT was obtained. Conclusion: PDT is an effective method for the inactivation of antibiotic-resistant pathogens, including in long non-healing wounds, contributing also to early tissue regeneration.

Spectroscopic approaches are very good to noninvasively determine the most significant indicators of the tissue state. Indocyanine green (ICG) is a well-known fluorescent dye approved for clinical applications, which has a short circulation time in the vascular system and low photostability. At high temperatures the molecular solution of the photosensitizer self-assembles into a stable J-aggregate form of ICG nanoparticles (ICG NPs) with the absorption peak in the near-infrared range. Investigation of ICG NP stability in human blood and plasma using a fiber-spectroscopic system demonstrates no difference in absorption properties and different dependence of the integrated fluorescence ratio between ICG monomers and J-aggregates in blood and plasma. Transition of ICG NP aggregates to the monomeric form in human blood plasma results in a higher circulation time of the fluorescent dye in the vascular system. High stability of aggregates and a low elimination rate may increase efficiency of fluorescent diagnostics of near-tumor tissues. [ABSTRACT FROM AUTHOR]

Intraoperative identification of healthy parathyroid and parathyroid adenomas facilitate a favorable outcome of surgical treatment of patients with parathyroid diseases and various hyperparathyroidism’s forms. In doing so, it is important to preserve the entire parathyroid tissue, since unintentional damaging, removal or devascularization leads to the most common development of complication – hypoparathyroidism, which occasionally becomes permanent. Although, in case of surgical treatment of patients with hyperparathyroidism, the removal of the whole pathologically altered tissue is needed in order to avoid the persistence and recurrence hyperparathyroidism, as confirmed by intraoperative and postoperative parathyroid hormone examination. Up to recent time, surgeons could had relied only on pre-surgical localization of hyperfunctioning parathyroid glands, thorough knowledge of front neck anatomy and personal experience, which wasn’t always reliable to recognize the parathyroids intraoperatively and differentiate the healthy parathyroid tissue from adenoma. To solve these problems, the auxiliary navigation and visualization methods, based on application of radiopharmaceutical and fluorescent agents, tropic to parathyroid tissue, are being actively implemented to endocrine surgery nowadays. The comparative characteristic of modern methods for intraoperative visualization of the parathyroid glands, based on the worldwide literature data, is represented in this article.

Photodynamic therapy (PDT) is an effective treatment option for the treatment of superficial basal cell carcinoma (sBCC). Recent publications have demonstrated that PDT with 7.8% 5‐aminolaevulinic acid nanoemulsion‐based gel (BF‐200 ALA‐PDT) is an effective and safe alternative for the treatment of sBCC). To investigate the efficacy and safety of 7.8% 5‐aminolaevulinic acid nanoemulsion‐based gel (BF‐200 ALA)‐PDT for the treatment of sBCC. A non‐controlled, open‐label single centre study was conducted. Patients received one PDT cycle with two PDT sessions one‐week apart. In case that clinical‐dermoscopy evaluation of treatment outcome revealed remaining lesions, a second PDT cycle was performed. The clinical results at the dermoscopy and fluorescence diagnosis level were histologically confirmed in all patients. Treatment response was evaluated 3, 6, and 12 months after last PDT session. A total of 31 patients (12 men and 19 women), with a median age of 63.74 years were included in this study. 3‐month after PDT‐session, 23/31 patients were complete responders (74.19%) after two BF‐200 ALA ‐PDT sessions. Esthetic outcome was considered good‐to‐excellent. 5 Aminolevulinic acid 7.8% nanoemulsion‐based gel (BF‐200 ALA) PDT is an effective therapy option for the treatment of sBCC. Complete clearance rates were higher in those patients who received only one PDT cycle. These results show a similar tendency as shown in other publications. [ABSTRACT FROM AUTHOR]

A comparative experimental study of the specific activity of drugs based on 5-aminolevulinic acid (5-ALA) and its hexyl ester (5-ALA HE) was carried out. Their ability to induce the synthesis of photoactive protoporphyrin IX in the healthy tissues of the rabbit bladder when instilling the drug solutions at various concentrations has been estimated. It was shown that 5-ALA HE results in the induction and accumulation of PPIX in the rabbit bladder epithelium at much lower concentrations than 5-ALA. Thus, a significant increase in the fluorescence intensity in comparison with the control was achieved by instillation of 5-ALA HE solution in the rabbit’ bladder at a concentration of only 0.0001% (fluorescence intensity 2.20±0.60 a.u.), and for 5-ALA – only when using a solution at a concentration of 0.3% (fluorescence intensity 2.60±1.02 a.u.).

The study demonstrates the ability of fluorescence diagnosis to perform intraoperative analysis of the bladder wall. The data of 10 patients with superficial bladder cancer who underwent PDD with the use of the fluorescence video system with excitation wavelenght in the "red" wavelength range and TUR is discussed. General condition of the bladder is assessed, the main foci of the tumor are determined. Then a tumor resection is performed. Further examination and identification of the fluorescing boundaries of the tumor remaining after TUR is performed to make a decision of a re‐resection. In addition, small fluorescing tumor foci, not detected with WL cystoscopy, are detected. Moreover the diagnostic fluorescence contrast is measured, allowing quantitative assessment of the 5‐ALA accumulation in tissues. The applied laser wavelength of 635 nm allows the light to penetrate deeper into the bladder tissue, making it possible to detect tumors including in the deeper layers. [ABSTRACT FROM AUTHOR]

This article describes a video endoscopy system intended for fluorescence‐based imaging of the tracheobronchial tree in the visible (VIS) and near‐infrared (NIR) regions of the spectrum. This system helps acquire both fluorescence images (VIS/NIR) and a white‐light image of the same area and has been developed on the basis of a standard bronchofiberscope with several diode lasers used as the light sources to excite Vis and NIR, the white‐light source, and photodynamic irradiation. A multimodal video system forms images and gives the possibility to perform targeted photodynamic therapy and control the dose of light irradiation through assessing the degree of photobleaching.The system capability is illustrated through clinical examples. The paper describes the procedure for photodynamic theranostics with chlorin e6 in patients with central lung cancer. The possibility of additional accurate localization of tumor lesions and their borders with NIR imaging is shown; to acquire a NIR image, a common dose of indocyanine green (ICG) used in angiography was administered to patients during the examination. It is also demonstrated that the same lesions can be identified using a combination of two dyes: chlorin e6 + ICG. [ABSTRACT FROM AUTHOR]

• Fluorescence Diagnosis with violet excitation • Contrast enhancement methods • Contrast can be increased by Red/Green and Red–Green methods • Ambient light suppression by time-resolved subtraction from the fluorescence frame • Endogenous fluorescence is suppressed by contrast enhancement methods Two Bispectral contrast enhancement approaches for the fluorescence diagnosis with chlorine-e6 and a wide field-of-view imaging system with fluorescence excitation at 405 nm and time-resolved background suppression were analyzed and compared. Two techniques for the contrast enhancement of a fluorescent video system (Red/Green (R/G) ratio and Red-Green (R-G)) with time-resolved background suppression for fluorescent diagnosis (FD) were tested in four patients with basal cell carcinoma (BCC). The results of both contrast enhancement methods were compared for the diagnostic efficiency for FD of BCC. Both techniques successfully determined the boundaries of the lesions and the fluorescence intensity. Both contrast enhancement modes have proven effective in identifying tumor borders in cases of low contrast in BCC FD with Ce6. While the Red/Green (R/G) mode provides sharper lesion borders, the Red minus Green (R-G) mode visualizes more fluorescent features and makes it easier to assess the lesion margins. [ABSTRACT FROM AUTHOR]

Results of autofluorescence dermatoscopy using videodermatoscope «EcoSkin» in patients with different dermatologic diseases are represented. The study included 64 patients, 27 of them had different types of psoriasis, 11 – acne, 3 – rosacea, 5 – eczema, 3 – mite-induced dermatitis, 4 – superficial mycosis of the glabrous skin, 7 – atopic dermatitis, 4 – seborrheic dermatitis. The major changes of autofluorescence were detected in pathological foci in patients with psoriasis. Authors suppose that increased autofluorescence of porphyrins in psoriatic plaques in the study is associated with enhanced prolyferation in pathological tissues and with liver dysfunction. The analysis of autofluorescence images in patients with rosacea, eczema, atopic and mite-induced dermatitis did not show significant difference in autofluorescence images of affected skin comparing with intact skin in same patients. In patients with acne a pattern of spot red-orange autofluorescence of skin in seborrheic areas corresponding with location of openings of pilosebaceous apparatus was detected that was associated by authors with Propionibacterium acnes infection.

The results of the study of subcellular distribution of molecular meso-tetra(3-pyridyl)bacteriochlorin nanocrystals proposed as therapeutic agents for photodynamic therapy are represented in the article. Investigations and measurement of spectroscopic properties of molecular crystals of near-infrared photosensitizer were conducted using special device complex based on fiber-optic spectrometer. Investigation and analysis of the pattern of subcellular accumulation of meso-tetra(3-pyridyl)bacteriochlorin in molecular (dimethyl sulfoxide (DMSO) as solvent) and nanocrystalline forms on different cell lines: human monocytes (THP-1), human cervical cancer cells (HeLa) and mouse malignant brain tumor cells (glioma C6). The dynamics of subcellylar accumulation of the agent at concentration of 5 and 10 mg/l was assessed with laser microscope-spectrum analyzer and by confocal microscopy. The study showed that in the course of interaction with cell lines molecular nanocrystals of the agent developed ability to fluorescence. Hence, in the cellular environment meso-tetra(3-pyridyl) bacteriochlorin nanoparticles became phototoxic giving opportunities for their use for fluorescence diagnosis and photodynamic therapy. Specific role of meso-tetra(3-pyridyl)bacteriochlorin in the range of photosensitizers is determined by its spectral characteristics, i.e. absorption and fluorescence in near-infrared band, which allows measuring and affecting on deeper layers of biotissue. Thus, the use of meso-tetra(3-pyridyl)bacteriochlorin nanoparticles as nanophotosensitizers may improve the efficacy of diagnosis and treatment of deep-seated tumors.

Objective: This study is to analyze fluorescence sensitivity in the diagnosis of brain and spinal cord tumors.Material and methods: The authors conducted a multicenter retrospective analysis of data on 653 cases in 641 patients: 553 of them had brain tumors and 88 spinal cord tumors. Brain tumor resection was performed in 523 patients, of whom 484 were adults and 39 children. The analyzed series was presented by 320 gliomas, 101 meningiomas, and 72 metastases. A stereotactic biopsy was performed in 20 patients and endoscopic surgery in 10 patients. In all cases, 20 mg/kg of 5–Aminolaevulinic acid was administered orally 2-h before surgery. All surgical interventions were performed with a microscope BLUE 400 to visualize fluorescence, while endoscopic surgery—with an endoscope equipped with a fluorescent module. Fluorescence spectroscopy was conducted in 20 cases of stereotactic biopsies and in 88 cases of spinal cord tumors.Results: Among adult brain tumors operated by microsurgical techniques, meningiomas showed the highest 5-ALA fluorescence sensitivity 94% (n = 95/101), brain metastases 84.7% (n = 61/72), low-grade gliomas 46.4% (n = 26/56), and high-grade gliomas 90.2% (n = 238/264). In children the highest 5-ALA visible fluorescence was observed in anaplastic astrocytomas 100% (n = 4/4) and in anaplastic ependymomas 100% (n = 4/4); in low-grade gliomas it made up 31.8% (n = 7/22). As for the spinal cord tumors in adults, the highest sensitivity was demonstrated by glioblastomas 100% (n = 4/4) and by meningiomas 100% (n = 4/4); Fluorescence was not found in gemangioblastomas (n = 0/6) and neurinomas (n = 0/4). Fluorescence intensity reached 60% (n = 6/10) in endoscopic surgery and 90% (n = 18/20) in stereotactic biopsy.Conclusion: 5-ALA fluorescence diagnosis proved to be most sensitive in surgery of HGG and meningioma (90.2 and 94.1%, respectively). Sensitivity in surgery of intracranial metastases and spinal cord tumors was slightly lower (84.7 and 63.6%, correspondingly). The lowest fluorescence sensitivity was marked in pediatric tumors and LGG (50 and 46.4%, correspondingly). Fluorescence diagnosis can also be used in transnasal endoscopic surgery of skull base tumors and in stereotactic biopsy.

The therapeutic properties of 5-aminolevulinic acid (5-ALA) have been extensively studied for cancer detection and treatment using photodynamic therapy (PDT). When administered externally, 5-ALA is converted to protoporphyrin IX (PpIX) in cancer cells, which generates reactive oxygen species (ROS) upon exposure to light. This process enables targeted cell death induction and cancer detection. Given the highly conserved nature of heme biosynthesis over billions of years, we hypothesized that natural mechanisms might exist to prevent excessive accumulation of PpIX or heme resulting from 5-ALA overload. Therefore, we anticipated alterations in protein expression profiles upon exogenous administration of 5-ALA. To understand cellular responses to 5-ALA, we investigated protein expression changes and identified OR1B1 as a promising target in bladder, prostate, lung, and cervical cancer cells. OR1B1 expression was observed only with 5-ALA and ferrous chloride, highlighting the central role of heme in this discovery. Immunofluorescence and electron microscopy confirmed OR1B1's sub-cellular localization. These findings suggest that 5-ALA transformation in cancer cells and OR1B1 expression have potential for enhancing cancer detection and developing alternative treatments, including immunotherapy. This approach overcomes the limitations of PDT and opens new avenues for effective and targeted cancer interventions. • This paper represents first complete proteomic analysis of the effects on cancer cells following exposure to 5-aminolevulinic acid (5-ALA). • 5-ALA triggers the down- or upregulation of >100 proteins. • Upon the analysis of significantly upregulated proteins, OR1B1 stands out, showing significant and specific upregulation following 5-ALA treatment without light with respect to its expression at the cellular membrane. • Heme and not protoporphyrin IX triggers the expression of OR1B1. • OR1B1 is a potential target for other imaging or treatment modalities in combination with 5-ALA. [ABSTRACT FROM AUTHOR]

Reliably established a causal role of human papillomavirus in the formation of condylomata acuminate. In 10% of people with the human papilloma virus develops condylomata acuminate, which can be transformed into malignant tumors. The most common treatment of condylomata acuminate is a conservative treatment, namely, the local chemical or physical destruction of the lesions and immunotherapy. With the ineffectiveness of conservative treatment resort to surgical excision. At the same time the traditional methods of treatment condylomata acuminate associated with high rates of recurrence. Moreover, these treatments are often associated with significant risk of bleeding, ulceration and scarring. The emergence of new methods of diagnosis and treatment of condylomata acuminate – fluorescence diagnosis and photodynamic therapy has opened up new opportunities to improve the treatment of this pathology. Topical administration of photosensitizers during photodynamic therapy is more convenient and less phototoxic and broaden the range of clinical applications of this technology in the medical dermatology. An increasing amount of evidence that photodynamic therapy with topical application of the photosensitizer is highly effective in the treatment of a variety of benign skin diseases, including condylomata acuminataca, for which traditional methods are ineffective treatment. However, many parameters of photodynamic therapy of this disease has not yet been optimized. It is necessary to conduct large-scale clinical studies on the effectiveness of photodynamic therapy of condylomata acuminatain order to standardize the treatment parameters.

The clinical case of successful use of local fluorescence spectroscopy combined with fluorescence imaging during cystoscopy for diagnosis of recurrent bladder cancer is represented in the article. Histological study of fluorescent foci confirmed tumor growth (urothelial carcinoma) in all areas with high levels of diagnostic parameter. In the fluorescent focus with low diagnostic parameter inflammation was detected.

Results of efficiency assessment of different diagnosis for preinvasive cervical lesions are represented in the article. During investigation the retrospective analysis of 353 patient histories of women with cervical intraepithelial neoplasia (primary and recurrent), who have been observed in Ivanovskiy regional oncological dispensary from 2002 to 2011, was performed. The accuracy rates of diagnosis of cervical intraepithelial neoplasia for one or several methods including cytological study, colposcopy and fluorescence cystoscopy were compared. Fluorescence diagnosis was performed with drug fotoditazin (LLC «VETA-GRAND», marketing authorisation №LS 001246) at dose of 1,0 mg/kg body weight. The final diagnosis was determined by results of histological study. The accuracy of cytological study accounted for 67,5–80,7%. Using colposcopy the exact diagnosis was determined in 67,9–74,4% of cases. Combination of cytological study with colposcopy improved the accuracy of diagnosis up to 82.1–88.9%. The superior results were for concurrent use of cytological study with colposcopy and fluorescence diagnosis – in such case the diagnosis was correct in 92,0–96,7% of patients. The analysis of results showed that using all methods of diagnosis the accuracy of diagnosis for recurrent cervical intraepithelial neoplasia was lower than for primary lesions. The decrease of diagnosis accuracy is probably related to previous diagnosis and therapeutic manipulations on cervix. Thus, multimodal diagnosis investigation with methods of fluorescence spectroscopy allows to improve accuracy of diagnosis for preinvasive cervical lesions.

The main challenge of treating non-muscle invasive bladder cancer is multifocal tumors. Current methods of diagnosis are failed to detect all superficial flat tumor lesions in bladder mucosa. The use of fluorescence imaging with 5-aminolevulinic acid (5-ALA) allows to improve the sensibility of routine cystoscopy, but low specificity decreases its diagnostic accuracy. The method of fluorescence imaging combined with local fluorescence spectroscopy developed in P.A. Herzen MCRI has been shown to increase the specificity from 71% to 84%. Thus, local fluorescence spectroscopy in visible fluorescence of 5-ALA-induced protoporphyrin allows to perform guided biopsy and decrease the rate of diagnostic mistakes.

The Medical Radiology Research Center Clinic performed photodynamic therapy (PDT) in 57 patients with cancer of the oral mucosa in the independent fashion. Pretreatment recurrent tumors were diagnosed in half (50.9 %) of the patients. Spectroscopy showed the therapeutic accumulation of the drug, which was 1.8–3 times greater than that in the skin and intact mucosa in the presence of a malignant neoplasm. Complete and partial tumor regression was achieved in 50 (87.7 %) and 4 (7 %) patients, respectively; stabilization was seen in 3 (5.3 %) patients. Three-year overall survival was 86.7 ± 5.2 % and three-year relapse-free survival was 70.5 ± 7.1 %. PDT has an organ-saving directionality, without causing functional and cosmetic impairments, thus showing its rather high effectiveness.

Results of fluorescence diagnosis (FD) with alasens in 237 patients with skin cancer are represented. The average age of patients accounted for 63±11 y.o. The indications for FD were the borders adjustment for skin cancer of different localizations prior to special treatment and also the search for occult foci of malignant lesion. There were two groups of patients: patients with locally advanced head and neck carcinomas, who had FD prior to surgical treatment, and patients with cancer of different localization, who had FD prior to photodynamic therapy (PDT). FD permitted to adjust borders of detected tumor foci in 100% of patients that impacted on extent of resection during surgery in group 1 of patients and helped planning fields of laser irradiation for PDT session in group 2 of patients. Due to FD with alasens 506 foci of additional fluorescence were detected in 118 (53.1%) of 222 patients in group 2, skin cancer was diagnosed morphologically in 63 patients (28.4%) of them.

• Fluorescence diagnosis with violet and red excitation provide comparable contrast. • Contrast can be increased by division of the red channel by green channel. • Background illumination is suppressed by time-resolved subtraction from the fluorescence frame. • Endogenous fluorescence is suppressed by division of the red channel to the green one. Fluorescence diagnostics with two different wide field-of-view imaging systems with fluorescence excitation at 405 nm and 635 nm, respectively, were compared. Both systems include fluorescence quantification and experimental geometry normalization algorithms. A newly developed system with an excitation wavelength of 405 nm was tested on intralipid fluorescent tumor phantoms with chlorin-e6. Both, this new system and a second existing system with an excitation wavelength of 635 nm, were used for fluorescent diagnosis in six patients with basal cell carcinoma and cancer of the oral mucosa. For PDT, a red diode laser with a wavelength of 660 nm was used for all 6 patients. One patient received an additional irradiation using the red LED source of the new system The boundaries of the lesions and the fluorescence intensity were successfully determined by both video systems. Both fluorescence imaging approaches showed comparable contrast between diseased and healthy tissues. For oral mucosal cancer, a system with violet fluorescence excitation, bispectral frame analysis, and time-resolved background suppression showed better contrast between the tumor and normal tissue and effective elimination of autofluorescence. Moreover, both systems provided efficient quantification of fluorescence and gave fluorescence indices that were weakly dependent on the distance between the device and the tissue. [ABSTRACT FROM AUTHOR]

The results of treatment in patients with skin cancer using the method of photodynamic therapy (PDT) with alasens are represented in the article. The study enrolled 25 patients with stage 1 tumor including 23 patients with previously untreated tumors and 2 – with recurrent disease. Superficial tumor was diagnosed in 17 patients and 8 patients had nodal tumor. Alasens was used locally as application of 20% ointment on involved skin area with 6h exposure. The PDT session was performed on a single occasion immediately after the end of exposure (power density of laser irradiation of 50–100 mW/cm2, light dose – 150–200 J/cm2). All patients had fluorescence diagnosis (FD) prior to application of the ointment and before PDT. The results of FD showed that intensity of porphyrin fluorescence in tumor prior to administration of alasens had near no difference from intensity of porphyrin fluorescence in normal skin (12.5±0.7 and 10.0±0.7 r.u., respectively). Six hours after application of the ointment with alasens the fluorescence intensity of protoporphyrin IX increased almost 5-fold (59.7±5.3 r.u.), the fluorescence intensity in normal skin remained near baseline level during the follow-up period (maximally 11.6±1.0 r.u.). Two months after PDT the complete tumor regression was confirmed in 21 patients, partial – in 3 and stabilization of tumor growth in 1 patient. In addition, patients with superficial disease had complete regression in 94.1% of cases and partial regression in 5.9% while for patients with nodal tumor – 62.5% and 25%, respectively, stabilization – in 12.5%.

The applications of multispectral autofluorescence imaging of malignant tumor was shown in in vitro and in vivo experiments. Using ТС-1 mouse tumor model it was demonstrated that the location of tumor formation can be clearly identified as early as 2 days after injection of tumor cells. Among observed effects the new one is an unusually active angiogenesis at early stage of tumor formation accompanied by atypical tortuous vessels with growth rate up to 3 mm/day. Two-wave excitation simultaneous laser with excitation on wavelength of 390 nm and 635 nm is shown to be promising for autofluorescence diagnosis along with single-wave excitation which is conventionally performed in the violet-blue region of the spectrum. This mode of excitation allows detecting the increased level of protoporphyrin IX even at early stage of carcinogenesis. The fluorescence due to active synthesis of protoporphyrin IX was shown to correlate with density of vessels. Increase of this fluorescence is observed also for aseptic inflammation but it has diffuse pattern which allows differentiating it from local fluorescence image at the site of tumor formation. The possibility of successful achievement of high-quality image using multispectral imaging and also optimization of registration settings were demonstrated in the experiment. The study of surgical specimen showed capabilities of imaging and measurement of autofluorescence in tumor tissue. The obtained results are intended to help in the development of endoscopic methods of imaging and devices for diagnosis of early tumors.

The technique of fluorescence hysteroscopy with Alasens includes visual assessment of fluorescence of Alasens-induced protoporphyrin IX and local fluorescence spectroscopy. The technique allows to improve the efficacy of early diagnosis for endometrial pathology including early endometrial cancer, to assess definitely an extent of pre-tumor and tumor process. The sensitivity of fluorescence hysteroscopy accounts for 100%, the specificity – 98%.

The technique of intraoperative fluorescence diagnosis with alasens for brain metastases includes visual assessment of alasens-induced protoporphyrin IX fluorescence and local spectroscopy. The technique allows to reduce the rate of misdiagnosis, to assess accurate local extent of brain metastases and to improve surgical radicality. When applying this technique the sensitivity of fluorescence diagnosis is 96.7%, the specificity is 100%. The technique is designed for neurosurgeons specialized on neurooncology.

Biophotonics and laser medicine are very dynamic and continuously increasing fields ecologically as well as economically. Direct communication with medical doctors is necessary to identify specific requests and unmet needs. Information on innovative, new or renewed techniques is necessary to design medical devices for introduction into clinical application and finally to become established after positive clinical trials as well as medical approval. The long-term endurance in developing light based innovative clinical concepts and devices are described based on the Munich experience. Fluorescence technologies for laboratory medicine to improve non-invasive diagnosis or for online monitoring are described according with new approaches in improving photodynamic therapeutic aspects related to immunology. Regarding clinically related thermal laser applications, the introduction of new laser wavelengths and laser parameters showed potential in the treatment of varicose veins as well as in lithotripsy. Such directly linked research and development are possible when researchers and medical doctors perform their daily work in immediate vicinity, thus have the possibility to share their ideas in meetings by day. [ABSTRACT FROM AUTHOR]

The study of efficacy of thoracoscopy-assisted fluorescence diagnosis with Alasens is described in the article. The results of fluorescence diagnosis in 27 patients with suspicion on pleral tumor are represented. Before thoracoscopy-assisted fluorescence diagnosis in 21 patients according to radiological studies there was a fluid in pleural ca, in 19 patients of them tumor cells were found by cytological study of pleural fluid, in 10 patients differential diagnosis was performed between mesothelioma and adenogenic cancer. For fluorescence diagnosis fluorescence system by company Кarl Storz and xenon lamp with set of light filters was used: fluorescence study was performed by excitation at wavelength 380–460 nm. 3 h before investigation the patient received alasens per os in dose of 30 mg/kg body weight in 100 ml of water. For routine thoracoscopy tumor lesions were determined in 20 (87.0%) patients, other 3 (13.0%) patients had no tumors. In the group of patients with tumor lesions determined by routine thoracoscopy the fluorescence during fluorescence study was registered in all lesions determined in white light, besides this 24 additional foci of fluorescence were noticed, according to morphological study 21 of them had tumor nature, 3 lesions were inflammatory. In 1 of 3 patients with no lesion in white light there was one focus of fluorescence, morphological study proved the metastasis of adenocarcinoma in this area. According to morphological study of pleural biopsy specimens the true-positive results for fluorescence thoracoscopy accounted for 82, false-negative – 10, true-negative – 23, false-positive – 3. The sensitivity of the method was 89,1%, the specificity – 88,4%, the diagnostic accuracy – 88,9%.

The method of fluorescence visualization of bladder tumors combined with fluorescence spectroscopy developed in P.A. Herzen MCRI is described. The efficacy of the method was proved by results of diagnostics in 198 patients with superficial bladder cancer. In the study group 67 patients had primary tumor, 131 patients had recurrence of superficial bladder cancer after previous treatment. In 3.5% patients the lesion was determined as carcinoma in situ, in 29.5% – non-invasive papillary carcinoma, bladder cancer with invasion into submucosal layer of bladder wall occurred in 67% of cases. Diagnostics was performed 1.5–2 h after instillation of 50 ml 3% solution of alasens into bladder. The data analysis was made with calculation of the diagnostic parameter and value of tumor/normal mucosa fluorescence contrast. The total number of fluorescence spectra accounted for 528. All determined areas of fluorescence were studied morphologically. During fluorescence spectroscopy 53 areas of fluorescence were determined on visually intact mucosa under white light, showed high values of diagnostic parameter. Morphological study proved severe dysplasia (3%), carcinoma in situ (95%) and bladder cancer (2%). Correlation between data of local fluorescence spectroscopy and morphological study of biopsy specimen was assessed, values of diagnostic parameter, характеризующих intact urothelium, areas of inflammation and moderate dysplasia, severe dysplasia and bladder cancer were estimated. Local fluorescence spectroscopy combined with visual assessment of fluorescence image allowed to increase specificity of cystoscopy from 70% to 85%, total accuracy – from 80% to 86%, with improvement of predictive value for positive result from 0,67 to 0,94.

The purpose of this review is to compile preclinical and clinical results on phthalocyanines (Pcs) as photosensitizers (PS) for Photodynamic Therapy (PDT) and contrast agents for fluorescence imaging. Indeed, Pcs are excellent candidates in these fields due to their strong absorbance in the NIR region and high chemical and photo-stability. In particular, this is mostly relevant for their in vivo activation in deeper tissular regions. However, most Pcs present two major limitations, i.e., a strong tendency to aggregate and a low water-solubility. In order to overcome these issues, both chemical tuning and pharmaceutical formulation combined with tumor targeting strategies were applied. These aspects will be developed in this review for the most extensively studied Pcs during the last 25 years, i.e., aluminium-, zinc- and silicon-based Pcs.

Oral cancer is among the most common malignancies worldwide, therefore early detection and treatment is imperative. The 5-year survival rate has remained at a dismal 50% for the past several decades. The main reason for the poor survival rate is the fact that most of the oral cancers, despite the general accessibility of the oral cavity, are not diagnosed until the advanced stage. Early detection of the oral tumors and its precursor lesions may be the most effective means to improve clinical outcome and cure most patients. One of the emerging technologies is the use of non-invasive in vivo tissue imaging to capture the molecular changes at high-resolution to improve the detection capability of early stage disease. This review will discuss the use of optical probes and highlight the role of optical imaging such as autofluorescence, fluorescence diagnosis (FD), laser confocal endomicroscopy (LCE), surface enhanced Raman spectroscopy (SERS), optical coherence tomography (OCT) and confocal reflectance microscopy (CRM) in early oral cancer detection. FD is a promising method to differentiate cancerous lesions from benign, thus helping in the determination of adequate resolution of surgical resection margin. LCE offers in vivo cellular imaging of tissue structures from surface to subsurface layers and has demonstrated the potential to be used as a minimally invasive optical biopsy technique for early diagnosis of oral cancer lesions. SERS was able to differentiate between normal and oral cancer patients based on the spectra acquired from saliva of patients. OCT has been used to visualize the detailed histological features of the oral lesions with an imaging depth down to 2–3 mm. CRM is an optical tool to noninvasively image tissue with near histological resolution. These comprehensive diagnostic modalities can also be used to define surgical margin and to provide a direct assessment of the therapeutic effectiveness.

Background The establishment of a precise and rapid method to detect metastatic lymph nodes (LNs) is essential to perform less invasive surgery with reduced gastrectomy along with reduced lymph node dissection. We herein describe a novel imaging strategy to detect 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence in excised LNs specifically with reduced effects of tissue autofluorescence based on photo-oxidation of PpIX. We applied the method in a clinical setting, and evaluated its feasibility. Methods To reduce the unfavorable effect of autofluorescence, we focused on photo-oxidation of PpIX: Following light irradiation, PpIX changes into another substance, photo-protoporphyrin, via an oxidative process, which has a different spectral peak, at 675 nm, whereas PpIX has its spectral peak at 635 nm. Based on the unique spectral alteration, fluorescence spectral imaging before and after light irradiation and subsequent originally-developed image processing was performed. Following in vitro study, we applied this method to a total of 662 excised LNs obtained from 30 gastric cancer patients administered 5-ALA preoperatively. Results Specific visualization of PpIX was achieved in in vitro study. The method allowed highly sensitive detection of metastatic LNs, with sensitivity of 91.9% and specificity of 90.8% in the in vivo clinical trial. Receiver operating characteristic analysis indicated high diagnostic accuracy, with the area under the curve of 0.926. Conclusions We established a highly sensitive and specific 5-ALA-induced fluorescence imaging method applicable in clinical settings. The novel method has a potential to become a useful tool for intraoperative rapid diagnosis of LN metastasis. [ABSTRACT FROM AUTHOR]

Background The preferential accumulation of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in neoplastic cells supports its potential use in the photodetection of epithelial tumours through porphyrin fluorescence. Objective To assess the validity of fluorescence diagnosis (FD) as an efficient pre-surgical in vivo imaging tool for defining the lateral boundaries of various types of basal cell carcinomas (BCCs). Methods The BCC tumour area was determined for 27 patients using FD digitalized imaging system, where the accumulation of PpIX in tumour tissue in relation to normal tissue was measured. Subsequently, BCCs were excised according to the complete area defined by FD using Mohs micrographic surgery (MMS). Results Of the 27 BCCs, the FD margin of the lesion coincided with the histopathological picture in 12 BCCs (44.44%). The mean value of accumulation factor (AF) was 2.7. Although 17 pigmented BCCs showed attenuated or absent fluorescence in the center, fluorescence at their periphery was used as a guide for excision, and statistically, the pigmentation of the BCCs showed no effect on the results of the FD efficacy ( p = 1.0). Conclusion Fluorescence diagnosis of BCC may be beneficial as a guide to the safety margin needed before MMS. The safety margin is decided according to the FD tumour diameter in relation to the clinical tumour diameter. [ABSTRACT FROM AUTHOR]

We have studied the feasibility of using an indotricarbocyanine dye as a marker for the efficacy of photodynamic therapy (PDT) of cancers with the photosensitizer Photolon. We have established that on exposure to laser emission at λ = 667 nm with an exposure dose of 100 J/cm, we observe that the Photolon concentration drops by about a factor of two in the exposed part of the tumor, while the concentration of the indotricarbocyanine dye does not change in any region of the tumor node. We have observed a correlation between the change in the shape of the fluorescence spectra of the indotricarbocyanine dye in vivo in the 780-880 nm resulting from a PDT session with the photosensitizer Photolon and the extent of damage to the tumor tissues. Changes in the shape of the fluorescence spectrum of the dye are interpreted in terms of a model involving the appearance of absorption by different forms of hemoglobin, and changes in their ratio in the exposed part of the tumor due to consumption of molecular oxygen. [ABSTRACT FROM AUTHOR]

Purpose Overexpression of epidermal growth factor receptor (EGFR) is observed in oral squamous cell carcinoma (OSCC) and is associated with increased proliferation, metastasis and therapeutic resistance. We aim to develop a novel drug delivery system comprised of a photosensitizer Chlorin e6 (Ce6) that is encapsulated in a viral envelope and tagged with anti-EGFR antibody to target OSCC. Methods Ce6 was encapsulated in both virosomes (Ce6-Vir) and virosomes tagged with anti-EGFR antibody (Ce6-Vir-EGFR′). In vitro studies were conducted to assess the cellular uptake and bioavailability of the photosensitizer in OSCC cells. Ce6 alone or in constructs was then administered in a hamster cheek pouch model and fluorescence imaging and spectroscopy was performed. Results In vitro results showed that the uptake of Ce6-Vir-EGFR′ was lower than that for Ce6-Vir and Ce6 possibly due to its large size. Nevertheless, in vivo results showed significant tumor specificity of Ce6-Vir-EGFR′ compared to Ce6. The tumor to normal mucosa ratio showed that Ce6-Vir-EGFR′ can successfully target OSCC lesions and therefore shows potential for use in fluorescence diagnosis of OSCC. Conclusions Both the virosome-Ce6 constructs were internalized by OSCC cells and successfully used for fluorescence imaging. Tagging with anti-EGFR antibody further improved the targeting ability toward OSCC. [ABSTRACT FROM AUTHOR]

The review is devoted to methods of targeted chemical modifications of bacteriochlorophyll a. These methods provide an approach to the synthesis of derivatives with improved photophysical properties and increased hydrophilicity and are suited to the design of conjugates with other biologically active molecules utilized for fluorescence diagnosis and binary cancer therapy. [ABSTRACT FROM AUTHOR]

The results of fluorescence diagnosis with alasens in patient with sigmoid polyps are represented in the article. Fluorescence study gave a suspicion of malignant transformation in one of polyps. According to morphological data there was a well-differentiated colon adenocarcinoma with underlying tubular adenoma in suspicious region. Thus, fluorescence data showed malignant tumor prior to routine histological study, which was misdiagnosed for routine colonoscopy and biopsy without fluorescence diagnosis.

Diseases are often accompanied by abnormal expression of gaseous signaling molecules including nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H 2 S). Sensing these gaseous markers is thus important for identification and investigation of pathological processes. In contrast to conventional approaches, such as electrochemical, chromatographical methods, etc., optical imaging shows merits including high sensitivity, good spatiotemporal resolution, and ideal selectivity. Especially, optical molecular probes with aggregation-induced emission (AIE) properties have good potential for bio-detection since they show maintained optical signals in the aggregated state. Recently, many AIE molecular probes have been developed for imaging disease-related gaseous signaling molecules. Generally, these probes recognize the analytes through turn-on or ratiometric approaches. This review summarizes the recent progress in organic probes with AIE properties for sensing gaseous markers and relative disease diagnosis applications. Based on the types of analytes, the probes are divided into three groups: NO, CO and H 2 S sensors. Molecular designs and sensing mechanisms of these AIE probes are highlighted. Their gaseous signaling molecules detection applications at cellular and animal levels are presented. Finally, some existing problems and future promising development directions are discussed with the hope to inspire further developments of AIE probes for precise disease diagnosis. [ABSTRACT FROM AUTHOR]

Background Basal cell carcinoma ( BCC) is the most frequent malignant tumor of the skin. The high prevalence of BCC, the risk of local recurrence, and the difficult clinical identification of the excision margins emphasize the importance of studying new approaches, ensuring complete surgical excision that allows preservation of normal tissue, especially for BCCs located on cosmetically important areas such as the mid face. Photodiagnosis ( PD) is a pre-operative technique that allows a more accurate distinction of neoplastic lesions from surrounding healthy skin in vivo. Purpose The aim of this study is to assess the usefulness of PD for the evaluation of tumor margins in 10 patients with recurrent BCC of the face. Methods We study the red fluorescence emitted by neoplastic tissue under a Wood's lamp irradiation, after accumulation of methyl amino levulinate ( MAL) cream in 10 patients with recurrent BCC. Results Our histologic analysis of perilesional skin by PD allowed to delineate more precise tumor margins, thus achieving radical excision in 90% of patients. Conclusion PD represents a diagnostic method that helps to distinguish between tumor tissue and surrounding healthy tissue especially in case of recurrent BCC of the face when the clinical delimitation is not clear. [ABSTRACT FROM AUTHOR]

Summary Background Monitoring of tumor burden during mycosis fungoides (MF) treatment, is crucial to adjust therapy accordingly. This is usually achieved through combined by clinical assessment with histopathological and immunohistochemical evaluation. Aim To assess the validity of fluorescence diagnosis (FD) in the measurement of response to therapy in early MF, using in comparison flow cytometric technique of skin biopsies for CD4+/CD7− malignant T-cell count before and after therapy. Patients and Methods Twenty-two patients of histologically proven early MF (stages Ia, Ib, IIa) were subjected to fluorescence diagnosis of their most affected skin lesion before and after 12 weeks of phototherapy with or without combination therapy. In comparison flow cytometric assessment of skin biopsies for CD4+/CD7− malignant T-cell count was evaluated before and after therapy from skin biopsy of the same lesion. Results All tested MF lesions showed varying degrees of fluorescence by FD at week zero, with a mean accumulation factor (AF), which is the fluorescence ratio between the tumor tissue and normal skin, of 2.2. After 12 weeks of therapy, the mean AF showed significant reduction to 1.94 ( p = 0.009). The percent of CD4+/CD7− cells dropped significantly after treatment ( p = 0.029). No correlation between CD4+/CD7− cell counts and the mean AF could be deduced. Conclusion In cases of mycosis fungoides, fluorescence diagnosis can represent an effective tool for evaluating the response to therapy. Changes in accumulation factor values can be used for follow-up of therapy in the same patient, but it should not be used as an absolute value. [ABSTRACT FROM AUTHOR]

Pigmented basal cell carcinoma (PBCC) occurs more frequently in Asian population. The efficacy of fluorescence diagnosis (FD) for PBCCs treated with Mohs micrographic surgery has not yet been determined. This study enrolled 255 patients with 258 biopsy-proven BCC lesions: 199 PBCCs (77.1%) and 59 non-PBCCs (22.9%). We compared the clinicopathological and surgical features of the PBCCs and non-PBCCs. Each group was divided into 2 sub-groups, those assessed and not assessed by FD, to retrospectively analyse surgical features. Aggressive histological subtypes were less prevalent in PBCCs than in non-PBCCs. PBCCs required significantly fewer stages of Mohs excision, with significantly smaller surgical margins and surgical depth, than non-PBCCs. FD did not confer any benefits on PBCCs during Mohs micrographic surgery. However, non-PBCCs assessed by FD required significantly fewer Mohs stages, with significantly smaller surgical margins, than lesions not assessed by FD. These findings suggest that FD should be performed before Mohs micrographic surgery to delineate the margins of non-PBCCs in Asians. [ABSTRACT FROM AUTHOR]

Summary: Background: As carcinogenesis is often accompanied by inflammation, fluorescence diagnosis (FD) of tumours reportedly leads to false positive results. However, an influence of inflammation on the efficiency of photodynamic therapy (PDT) is not known. Objective: Therefore we investigated whether LPS-induced expression of the pro-inflammatory cytokine interleukin-6 (IL-6) influences hypericin and protoporphyrin IX (PpIX) accumulation, and their photocytotoxicity. As in vitro models served normal and malignant human skin cell lines. Additionally we analyzed whether low-dose photodynamic treatment as found during FD and sublethal PDT could modulate the expression of IL-6 and other cytokines as low-dose PDT has the potential for treatment of inflammatory skin diseases. Methods: Cells were pre-incubated with LPS to induce a pro-inflammatory milieu. Photosensitizer accumulation and toxicity were measured by a microplate reader, IL-6 via Sandwich ELISA and the other cytokines via a Multiplex Immunoassay. Results and conclusions: Neither hypericin uptake nor PpIX accumulation was influenced by the proinflammatory state. The false positive classification in FD of patients could rather be due to sensitizer-loaded immune cells. On the other hand, low dose PDT is able to significantly reduce the level of IL-6 in all cell lines. Under differing PDT-conditions, PDT can enhance IL-6 in malignant cells, which could elicit a specific anti-tumour immune response. Furthermore, hypericin alone is able to up-regulate the anti-inflammatory cytokines IL-4, -5 and -10, which could be useful to reduce excessive inflammation. LPS-induction has no additional influence in most cases. Some of these findings could contribute to abate inflammatory diseases on skin or promote wound healing. [Copyright &y& Elsevier]