Photodiagnosis and photodynamic therapy最新文献

Background: Between 2003 and 2016, 546 patients in our clinic discontinued outpatient treatment for actinic keratoses (AKs) using conventional photodynamic therapy (PDT) because of intolerable pain, thereby necessitating the use of a less painful procedure. Therefore, we developed a novel off-label PDT protocol: 'PDT light'.

Methods: Laser-assisted low irradiance PDT (li-PDT) was performed beginning in 2014. The dosage was gradually lowered to 8-12 J/cm² in 2018, so that we achieved considerable pain reduction while maintaining comparable therapeutic efficacy. A further considerable reduction in pain was achieved from 2018 onwards by combining the advantages of li-PDT with daylight PDT (DLPDT), thereby resulting in 2018 in the new technique 'PDT light'. Patients with AK Olsen grades 1 or 2 and field cancerization initially received a mild-fractionated CO2 laser pretreatment prior to MAL-incubation (methyl aminolaevulinate, Metvix ®) under occlusion for 1.5-3 h. Then, patients were illuminated on average for 1.02 min with the Aktilite-LED and, after application of an UV-screen on the illuminated area, sent out into daylight for 1 h.

Results: Between March and November 2019, we successfully treated 152 cases using the enhanced 'PDT light' procedure, with 137 cases achieving at follow-up 1 (on average after 8.14 months) good-to-excellent clearance rates (CLA and CLB together 90%) and minimal adverse effects.

Conclusions: The novel 'PDT light' protocol proved to be an excellent and nearly painless method with an average visual-analogue scale (VAS) score of 1.19. Additional advantages included reduced illumination time, shorter outpatient stays in the clinic, fewer adverse effects, and better patient compliance than with DLPDT alone.

Background: Accurate light dosimetry is a complex remaining challenge in interstitial photodynamic therapy (iPDT) for malignant gliomas. The light dosimetry should ideally be based on the tissue morphology and the individual optical tissue properties of each tissue type in the target region. First investigations are reported on using NMR information to estimate changes of individual optical tissue properties.

Methods: Porcine brain tissue and optical tissue phantoms were investigated. To the porcine brain, supplements were added to simulate an edema or high blood content. The tissue phantoms were based on agar, Lipoveneous, ink, blood and gadobutrol (Gd-based MRI contrast agent). The concentrations of phantom ingredients and tissue additives are varied to compare concentration-dependent effects on optical and NMR properties. A 3-tesla whole-body MRI system was used to determine T₁ and T₂ relaxation times. Optical tissue properties, i.e., the spectrally resolved absorption and reduced scattering coefficient, were obtained using a single integrating sphere setup. The observed changes of NMR and optical properties were compared to each other.

Results: By adjusting the NMR relaxation times and optical tissue properties of the tissue phantoms to literature values, recipes for human brain tumor, white matter and grey matter tissue phantoms were obtained that mimic these brain tissues simultaneously in both properties. For porcine brain tissue, it was observed that with increasing water concentration in the tissue, both NMR-relaxation times increased, while µ_a decreased and µ_s' increased at 635 nm. The addition of blood to porcine brain samples showed a constant T₁, while T₂ shortened and the absorption coefficient at 635 nm increased.

Conclusions: In this investigation, by changing sample contents, notable changes of both NMR relaxation times and optical tissue properties have been observed and their relations examined. The developed dual NMR/optical tissue phantoms can be used in iPDT research, clinical training and demonstrations.

Background: The study is aimed at developing a method for monitoring photodynamic therapy (PDT) of a tumor using chlorin-type photosensitizers (PSs). Lack of monitoring of chlorin e6 (Cе6) photobleaching, hemoglobin oxygenation and blood flow during light exposure can limit the PDT effectiveness.

Materials and methods: Phototheranostics includes spectral-fluorescence diagnostics of Ce6 distribution in the NIR range and PDT with simultaneous assessment of hemoglobin oxygenation and tumor blood flow. Fluorescence diagnostics and PDT were performed using the single laser λ_exc=660 ± 5 nm.

Results: Combined spectroscopic PDT monitoring method allowed simultaneous estimation of Ce6 photobleaching, hemoglobin oxygenation and tumor vascular thrombosis during PDT without interrupting the therapeutic light exposure.

Conclusion: The developed method of tumor phototheranostics using chlorin-type PSs may make it possible to personalize the duration of therapeutic light exposure during PDT.

Background: Photodynamic therapy (PDT) is receiving increasing attention in treating non-small cell lung cancer (NSCLC) worldwide, but in clinical practice, the relationship between treatment effect and PDT light dose in NSCLC remains unclear. Therefore, we aimed to determine the optimal light dose for PDT by exploring molecular biomarkers and evaluating tumor growth data.

Methods: We applied bioinformatics to identify promising genes and pathways in NSCLC and PDT. Then, the human lung adenocarcinoma cell line A549-bearing BALB/c nude mice were treated with hematoporphyrin derivative (HPD, 3 mg/kg) that is currently used widely for lung cancer treatment in the world even with photosensitization issues. After 48 h, tumor-bearing mice were irradiated superficially at doses of 100, 200, 300, 400, and 500 J/cm². The tumor growth data and apoptotic molecules were assessed and calculated.

Results: Bioinformatics results indicated that the apoptosis pathway was significantly enriched and caspase 3 was the most promising biomarker on prognosis in NSCLC-PDT. Compared to the untreated group, there was no difference in the relative tumor volume (RTV) of the 100 J/cm² group, while the RTV of the other treatment groups (200-500 J/cm²) was significantly lower. In the 100 J/cm² group, there were significant differences in the complete remission (CR, 0 %) and the percentage of tumor growth inhibition rate (TGI%) over 75 % (20 %) compared with the other treatment groups, especially the 300 and 400 J/cm² groups (CR 70 %; TGI% 90 %). In the 300 and 400 J/cm² groups, the expression of caspase 3, cleaved-caspase 3, PARP1, and Bax was increased significantly, while Bcl-2 expression was significantly lower.

Conclusions: Moderate doses of PDT (300 or 400 J/cm²) are more effective than low (100 or 200 J/cm²) or high doses (500 J/cm²) in the A549 tumor-bearing mice model. Since the A549 tumor is more akin to human tumors in pathological behavior, these experimental data may contribute to improving HPD-PDT illumination protocols for favorable clinical outcomes.

Background: Moderate-to-severe acne vulgaris, which is a chronic inflammatory skin disease, seriously impacts millions of people. However, traditional therapies may cause severe adverse reactions that are unacceptable to many patients, thus limiting the further application of these therapies. Novel therapeutic approaches to effectively treat moderate-to-severe acne vulgaris with minimal adverse reactions are urgently needed. In this retrospective study, we investigated the efficacy and adverse reactions of photodynamic therapy (PDT) using 560-1200 nm followed by 420-1200 nm broadband light (BBL).

Methods: Twenty-four patients with moderate-to-severe acne vulgaris were included in the study and all patients expressed a strong desire for beauty. After aminolevulinic acid (ALA) gel applied, the entire face was sequentially irradiated by using BBL with a 560 nm cut-off filter (560-1200 nm), followed by BBL with a 420 nm cut-off filter (420-1200 nm). The clinical efficacy was evaluated by the proportion of patients achieving cured response and excellent response (effective rate), based on the percentage of lesions reduction (treatment rate). The fluorescent images and photographs of acne vulgaris were recorded. Pain and other common local adverse reactions during the treatment were also recorded and evaluated.

Results: In patients with moderate acne, the mean treatment rates were 57.74 ± 16.40 (%) and 87.40 ± 8.521 (%) at the 6th week and 12th week of treatment, respectively. In patients with severe acne, the mean treatment rates were 60.95 ± 12.06 (%) and 85.04 ± 9.115 (%) at the 6th week and 12th week of treatment, respectively. At the 6th and 12th weeks of treatment, the effective rates of patients were 20.00 % and 93.33 % in patients with moderate acne, and 0.000 % and 88.89 % in patients with severe acne, respectively. Pain scores were significantly higher in patients with severe acne compared to patients with moderate acne when receiving 560-1200 nm BBL-PDT. Additionally, patients when receiving 420-1200 nm BBL-PDT exhibited significantly higher pain scores than those when receiving 560-1200 nm BBL-PDT. The degree of erythema was more severe in patients with severe acne than in those with moderate acne. The pigmentation was observed in one patient with moderate acne and one patient with severe acne.

Conclusion: The 560-1200 nm and 420-1200 nm BBL-PDT therapy can effectively treat moderate-to-severe acne vulgaris with tolerable adverse reactions, providing a new option for patients with higher esthetic requirements.

Background: The objective of this study was to evaluate the effect of bleaching techniques, including or not the use of violet light (405-410 nm), on resin-based composites' color, surface roughness, nanohardness, and elastic modulus.

Methods: Ninety-six disk-shaped specimens (12 mm x 2 mm; n = 12) were prepared using Filtek Z350 XT (Z350) and IPS Empress Direct (ED) resin-based composites. After 24 h, specimens were stained in red wine for 28 days. After staining, specimens were divided into four experimental groups: 40 % Hydrogen Peroxide (HP); Violet Light (VL); 40 % Hydrogen Peroxide associated with Violet Light (HP+VL), and a control group - no treatment (NT). Specimens were evaluated at six experimental times: initial (24 h after light curing); after staining and after the 1st, 2nd, 3rd, and 4th bleaching sessions regarding the color change (ΔE₀₀, L*, a*, b*, and WI_D); roughness (Ra), nanohardness and elastic modulus (GPa). Two-way analysis of variance for repeated measures was performed (α=0.05 %).

Results: There was a statistically significant difference between staining and the 1st bleaching session for all ED groups (p<0.05). After the last bleaching session, there were no differences between the experimental and the control groups of both resin-based composites. Bleaching using violet light did not change the roughness, nanohardness and elastic modulus of the tested resin-based composites (p>0.05).

Conclusions: Although hydrogen peroxide and violet light remove pigments from resin-based composites without affecting their surface roughness, nanohardness, and elastic modulus, the color change was similar to the one obtained by immersion in distilled water.

Cutaneous squamous cell carcinoma (cSCC) is a prevalent malignant tumor typically treated through surgical removal. However, when the lesion is situated in specific areas like the hands, feet, or lips, particularly if it's sizable, surgical interventions can adversely impact appearance and function. In such cases, non-surgical treatments are preferable to preserve both aesthetics and functionality. We present a case of recurrent cSCC on the plantar region post-surgery. Given the extensive lesion area, deep infiltration, and the patient's reliance on foot function, hematoporphyrin derivative-photodynamic therapy (HpD-PDT) was chosen over traditional surgery. The lesion was successfully treated, and while a minor recurrence was observed after 20 months, it was localized and amenable to non-surgical intervention. We posit that HpD-PDT is a viable treatment for cSCC, especially in unique locations, with extensive lesions, and postoperative recurrence.