Soft tissue sarcoma is a rare malignant neoplasm. Despite the improvement of surgical techniques, the rate of relapses of the disease remains high. The search for alternative methods of treatment is relevant.
Purpose. To evaluate safety and effectiveness of intraoperative photodynamic therapy of sarcoma in soft tissues.
Material and methods. Forty-four patients with soft tissue sarcoma were included in the study. Patients were divided into three groups. Group 1 (n = 10): soft tissue sarcoma of stage T2-3N0M0G1, surgical treatment and intraoperative photodynamic therapy. Group 2 (n = 17): soft tissue sarcoma of stage T2-3N0M0G2-3, surgical treatment and intraoperative photodynamic therapy. Group 3 (n = 17): soft tissue sarcoma of stage T2-3N0M0-1G2-3, combined treatment – preoperative light therapy, surgical treatment, intraoperative photodynamic therapy, neoadjuvant and adjuvant chemotherapy. Fluorescence spectrometry was performed to determine the degree of photosensitizer accumulation in tumor tissue. Treatment methodology: photosensitizer was injected 2.5–3 hours before the surgery. The tumor was removed with resection of adjacent muscles and healthy tissues. Then, laser irradiation of the tumor bed was made using “Latus” device. Radiation power was up to 2,5 W, power density was up to 0,28 W/cm2, radiation dose was up to 100 J/cm2. Follow-up ranged from 14 to 44 months.
Results. The spectrometry has revealed that photosensitizer was accumulated predominantly in tumor tissue. There were no reactions to photosensitizer injection, no changes in the tumor bed as well as no increase in wound healing period after intraoperative photodynamic therapy.
Within the observation period, all patients stayed alive. Relapses of the disease were registered in 38.7 % of patients: in Group 1 – 30 %, in Group 2 – 35.3 %, in Group 3 – 53 %. Of the 20 patients with primary diagnosed neoplasms, relapses were seen in 30 %. Of the 24 patients with previously recurrent neoplasms, 45.8 % had repeated relapses.
Conclusion. Intraoperative photodynamic therapy is a safe and effective technique for treating soft tissue sarcomas; it is also the promising direction for research. A small number of observations, a variety of histological forms and stages of the disease make it difficult to assess the effectiveness of the discussed approach. Further studies of intraoperative photodynamic therapy are required.

A case report of the application of endoscopic photodynamic therapy in a patient with inoperable squamous-cell cancer of the middle-thoracic part of the esophagus is presented. Two sessions of photodynamic therapy with a 1.5 month interval have been performed. Photosensitizer Photodithazin and a diode laser were used for the treatment. No complications were observed. The treatment resulted in a complete tumor resorption.

A clinical case of simultaneous laser obliteration in a patient with recurrent varicose veins and a Baker’s cyst is presented. As has been demonstrated, simultaneous laser obliteration of varicose veins and a Baker’s cyst is a safe and effective technique which allows to improve outcomes after treatment, to reduce rehabilitation period and to avoid complications.

Purpose: to compare the effectiveness of laser therapy and traditional methods for managing diabetic patients with purulent-necrotic lesions in their lower extremities.
Material and methods. The article presents a retrospective analysis of outcomes after treatment of 76 patients with diabetes mellitus having purulent-necrotic lesions in their lower extremities. Patients were divided into two groups. The first (main) group consisted of 34 patients in whom traditional treatment was accompanied by intravenous laser blood irradiation and local laser therapy; the second (control) group consisted of 42 patients who received only traditional treatment.
Results. Laser therapy contributed to more rapid reduction of wound defect (17.4 %) compared to patients after traditional treatment (11.1 %); it reduced the period of transition to inflammatory-regenerative changes, promoted a smaller number of high amputations of lower limbs from 14 to 6 % as well as shortened the length of hospital stay by 11.2 days.
Conclusion. Laser light therapy in patients with diabetic foot accelerates cleansing and reduction of the wound area, allows to reduce or eliminate inflammatory process in shorter time than with traditional treatment.

Material and methods. The trial included 20 patients. The main group consisted of 10 patients with chronic gingivitis, the control group – of 10 patients with clinically healthy parodontium. For the purpose of diagnosis, a survey, examination, clinical and functional studies, including laser Doppler flowmetry and optical tissue oximetry, were used. Photodynamic therapy was used for treatment.
Results and discussion. In patients with chronic gingivitis, unsatisfactory condition of their oral cavity was clinically revealed before treatment — decrease of the functional indices of microcirculation and saturation together with the increase of the clinical indices. After treatment, clinical recovery and improvement of clinical and functional indicators were noted.
Conclusion. The present trial showed a statistically significant improvement in clinical and functional parameters after treatment, in comparison with the baseline findings before it.

Purpose. To study specific approaches for selecting patients with rhonchopathy and obstructive sleep apnea syndrome for surgical treatment and to study laser surgical techniques applied on the soft palate so as to identify basic reasons of postoperative complications, soft palate function disorders and relapses of the disease with an even more aggressive course than before the surgery.
Material and methods. In 2011–2020, 523 patients with rhonchopathy and obstructive sleep apnea syndrome, aged 23–78, were selected for surgical treatment. The authors discuss the obtained data after analyzing the effectiveness of used criteria for selecting patients for laser-assisted surgery on the soft palate, as well as after analyzing outcomes after laser sculptural uvulopalatoplasty performed in 309 patients. Reasons for insufficient effectiveness of surgery in some patients have been analyzed too.
Results. After analyzing selection criteria, it has been found out that only 309 patients out of 523 (59.1 %) had no contraindications to laser sculptural uvulopalatoplasty, while 214 patients (40.9 %) had them. The discussed surgery was effective in 304 out of 309 operated patients (98.4 %) which has been confirmed with a complete and stable relief from night snoring and its complications for five or more years after the surgery. No effect was registered in 5 (1.6 %) patients because they absolutely ignored strict following the prescribed regimen, diet and other recommendations aimed to promote physiological healing of surgical wounds.
Conclusion. The effectiveness of laser sculptural uvulopalatoplasty depends on a careful and adequate selection of patients for this surgery as well as on rational choice of laser light parameters; failures are due to inadequate selection of patients and their unwillingness to strictly follow recommendations in the postoperative period.

Purpose: to construct a physical model based on the theory of activated complex (TAC) with indicators ΔH and ΔS mentioned in works of G.I. Zheltov and his colleagues so as to assess the impact of laser radiation micropulse modes at the chorioretinal complex (CRC), as well as to compare it with models based on the Arrhenius integral and with results of micropulse mode testing using autofluorescence method.
Material and methods. Modeling of the degree of damage to CRC and adjacent structures was carried out using Eyring equation. Values of ΔH = 360 000 J/mol and ΔS = 890 J/mol·deg for complex of proteins and other RPE organic structures were determined by G.I. Zheltov and co-authors in vivo in a series of laser experiments on primates. For modeling, absorption coefficient of 460 cm–1 was used, for wavelength 577 nm – 10-micron-thick RPE layer and transmission 37 %. Micropulse mode testing (50 μs, 2.4 %, 10 ms, 100 mkm, 0.4–1.9 W) was performed using Navilas 577s navigation laser in patients aged 35–46 with appearance of types 2–3 by the Fitzpatrick scale; results of this testing were assessed using short-wave autofluorescence (488 nm) method.
Results. A physical model based on TAC and Eyring integral was constructed. Results of modeling of the degree of RPE injury depending on power coincide with the results of testing of micropulse mode in patients according to autofluorescence method. The average RPE absorption coefficient equal to 440 cm–1 for patients aged 35–46 years and with appearance of type 2–3 by the Fitzpatrick scale was clarified.

Conclusion. The computer modeling based on TAC using the Eyring equation with ΔH and ΔS for a complex of proteins and other RPE organic structures, which are described in works of G.I. Zheltov and his co-authors, has shown a high degree of compliance with the results of micro-pulse mode testing in real patients. Modeling does not require adjustment of any free parameters unlike approaches based on the Arrhenius equation; it also allows to find absorption coefficients for a small sample of patients and to assess the level of laser radiation damage to RPE and adjacent structures.

Transepithelial photorefractive keratectomy (TransPRK) with excimer laser “Microscan Visum” (1100 Hz) is a one-stage surgery which does not require changing the sequence of stages for epithelium removal and ablation of cornea stromal part. The “know-how” of Russian excimer laser manufacturers allows to significantly reduce corneal tissue overheating during TransPRK surgery. A new approach to TransPRK surgery consists in simultaneous use of Platoscan program, age nomogram and size of epithelium initial thickness.
Purpose: to assess functional outcomes and changes in the corneal epithelium thickness after TransPRK surgery in patients with myopia in the period from 1 month to 1 year.
Material and methods. Sixty-six eyes of 33 patients were included in the trial. Average patients’ age was 25.6 ± 6.8 (mean 17–40); 18 men and 15 women. The average spherical component was –2.57 ± 1.54 diopters (from –0.75 to –5.75). The average cylindrical component before surgery was –0.79 ± 0.71 diopters (from 0.00 to –3.5); 45 eyes with mild myopia, 21 eyes with moderate myopia. Epithelium thickness was measured with RTVue-xR Avanti device (Optovue, USA). Calculations were made using Platoscan program and age nomogram (OOO “Opto-systems”, Russia). Assessment of functional outcomes was made using generally accepted standards in refractive surgery.
Results. TransPRK has shown its high efficacy, safety, predictability and accuracy in patients with myopia correction. Analysis of OCT findings of the anterior segment using epithelial maps showed that there is no complete restoration of epithelium thickness both in cornea center and in cornea periphery in 7-mm zone by the end of the first month after TransPRK surgery. In one month after TransPRK, epithelium thickness restored by 86.64 % in the center and by 87.99 % in 7-mm zone. Complete restoration of epithelium thickness in the center and in periphery was reached in 6 months. Corneal epithelium thickness in the surgical field increased by 7.9 % both in the center and in periphery in 12 months after the surgery. The ratio of epithelium initial thickness in the center and in periphery to the total cornea thickness before and after the surgery was 10–12 % for the entire study period.

Purpose: to study the dynamics of morphofunctional parameters of thyroid mast cells under low-intensity laser irradiation depending on age. Material and methods. The experiment was conducted on 96 white male laboratory rats of the Wistar breed. Animals were divided into four groups: 1 – control young, 2 – control old, 3 – young, low-intensity laser irradiation, 4 – old, low-intensity laser irradiation. A single laser irradiation session in continuous mode (wavelength – 970 nm, power – 1 W, exposure – 60 s) was made in the projection of thyroid gland. The animals were removed from the experiment 1 hour and 1, 3 and 7 days after exposure to laser light. Thyroid preparations were fixed in the formalin; histological sections were prepared and stained with toluidine blue; the morphometric analysis was performed to determine the number of thyroid mast cells and their varieties depending on the granular saturation level and degranulation degree.
Results. The reaction of thyroid mast cells of experimental animals to laser exposure had some specific features: in young animals there was the increase in the number of cells and in their synthetic activity with the increase in granular saturation level and with the decrease in degranulation level which indicates an increased migration of cells into the thyroid gland and a pronounced adaptive reaction of the entire population of mast cells of the body. In old animals, exposure to laser light caused degranulation activity of thyroid mast cells with decrease in the level of granular saturation. No changes in the number of cells indicates that the reaction is limited within the organ contours.
Conclusion. The results obtained expand our understanding of specific reactions of mast cells to laser exposure and confirm the need for individual correction of low-level laser therapy depending on age.

A clinical case of the successful use of light-oxygen therapy is presented irradiation in the absorption spectrum of endogenous oxygen with its transfer to a singlet state in a patient with vulvar leukoplakia and lichen sclerosus. As a source of laser radiation, we used the domestic Super Sab diode laser with a wavelength close to 1265 nm (OOO New Surgical Technologies, Moscow), radiation power – from 0.9 to 1.2 W, power density – from 0.8 to 1.06 W/cm2, exposure dose – 200–250 J/cm2. The procedures were carried out 2 times a week with an interval of 3–4 days.
As a result of the treatment (8 procedures), complete clinical remission was achieved.