Photobiomodulation, photomedicine, and laser surgery最新文献

Objective: To determine how Erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation affects the proliferation and transcriptional programs of MLO-Y4 osteocyte-like cells.

Background: Although Er:YAG lasers are widely used in periodontal hard tissue therapy, how they affect osteocytes remain elusive.

Materials and methods: MLO-Y4 cells were seeded before 72 h Er:YAG laser irradiation at energy fluences of 3.1, 6.0, and 8.9 J/cm². Cell surface temperature and Hspa1a expression were measured to evaluate thermal effects. Cell proliferation and cytotoxicity were assessed by the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays. RNA sequencing (RNA-seq) was performed 6 h after 6.0 J/cm² laser irradiation versus nonirradiated controls.

Results: According to surface temperature and Hspa1a expression, no major thermal effects were observed at 6.0 J/cm². The CCK-8 assay revealed significantly increased proliferative activity, although LDH levels were slightly but significantly increased at 6.0 J/cm² laser irradiation. RNA-seq identified 337 differentially expressed genes (DEGs). Expression of mechanical stimulation-associated genes, including Epha2, Itga5, and Tcf7, was highly upregulated in the laser-irradiated cells. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed upregulation of the PI3K-Akt signaling pathway in the laser-irradiated cells. Upregulated DEGs belonged to the "euchromatin" cellular component Gene Ontology term in the laser-irradiated cells. Gene set enrichment analysis showed enrichment of the Transforming Growth Factor Beta (TGF-β) signaling gene set and downregulation of mechanistic target of rapamycin (mTORC1) signaling gene set in the laser-irradiated cells.

Conclusion: Er:YAG laser irradiation at 6.0 J/cm² promotes MLO-Y4 osteocyte-like cell proliferation via altering gene expression, possibly by activating PI3K-Akt and TGF-β signaling while suppressing mTORC1 signaling.

Objective: Temporomandibular joint disorders (TMDs) are multi-factorial conditions with a chronic progression that affects individual's quality of life (QOL).

Background: Currently, there is no definitive treatment for TMDs. Few clinical trials have investigated the potential effects of Photobiomodulation therapy on the acupuncture points on these disorders.

Methods: Twenty patients with TMD, referred to the facial pain clinic at Semnan Faculty of Dentistry, were randomly assigned into two groups: treatment (n = 10) and placebo (n = 10).Treatment group received low-power Photobiomodulation therapy for 3 min at each of 10 acupuncture points, including GB20, SI19, ST6, ST7, and LI4. The placebo group received only the guiding light of the device on the same points. Treatment consisted of 10 sessions (twice a week). QOL was assessed using the OHIP-14 and SF-36 questionnaires at the beginning and end of treatment.

Result: Significant differences were observed between the treatment and placebo groups according to pain relief and maximum mouth opening (p < 0.05; Mann-Whitney). However, no significant difference was observed between the groups for the QOL using OHIP-14. In contrast, the SF-36 showed significant improvements in the physical health subscale in the treatment group.

Conclusions: Photobiomodulation therapy on the acupuncture is a complementary, noninvasive therapy that may benefit patients with TMDs.

Background: Laser hemorrhoidoplasty (LHP) has emerged as a minimally invasive alternative to excisional hemorrhoidectomy, but data remain heterogeneous, particularly regarding energy settings and safety outcomes.

Methods: This multicenter retrospective cohort included 100 patients with symptomatic grade III hemorrhoids treated with LHP across six Brazilian centers between January 2021 and August 2023. Primary outcomes were postoperative pain (Visual Analog Scale-VAS), proctological symptoms (Proctological Symptoms Scale-PSS), and complications. Associations between total laser energy and complications were analyzed using multivariable logistic regression.

Results: Median VAS peaked at 3.0 on day 7 and declined to near-complete remission by day 14, remaining minimal up to 1 year. PSS scores improved in parallel, reaching zero from day 30. The 30-day complication rate averaged 19.7%, peaking at 27% on day 14, with a cumulative per-patient rate of 44%. Most complications were mild (edema, skin tags), and only four patients required reintervention. Higher total energy was associated with increased complications from day 14 onwards, although the clinical effect was modest. Adjunctive CO₂ laser excision of skin tags (n = 49) did not increase morbidity.

Conclusions: LHP proved safe and effective for grade III hemorrhoids, ensuring early pain relief and symptom resolution with high satisfaction. Energy standardization may help minimize risks, and adjunctive CO₂ skin-tag excision appears feasible without added morbidity.

Background: Fractional carbon dioxide (CO₂) laser is the standard treatment in facial rejuvenation for light skin phototypes; nevertheless, in Latin America, it is one of the most performed procedures on phototypes III-V.

Aim: The goal of this study is to evaluate the improvement in facial skin aging in Latin skins with fractional CO₂ laser and its side effects in a period of 3 months.

Materials and methods: Descriptive multicenter cross-sectional study including 165 patients from 2 medical centers in Latin America who attended from 2014 to 2021. Data were collected from medical records and assessment of facial aging was performed through photographic records by two independent investigators. An arithmetic mean was obtained for each variable and for each researcher, subsequently the obtained values were averaged to find the overall average improvement according to the intervention and skin phototype. A Cohen's Kappa Concordance Test was performed to determine the agreement between observers beyond chance.

Results: Significant improvement in fine lines, mottled pigmentation, and overall skin appearance was observed in patients treated with fractional CO₂ laser with or without platelet-rich plasma. As for side effects, only one patient presented with herpes simplex.

Conclusions: There are few studies to date that evaluate the use of fractional CO₂ laser in Latin skins, through this research, it is evident that this technology has good results for facial rejuvenation in this type of patients and few side effects.

Objective: To propose a mechanistic framework for the use of transcranial photobiomodulation (tPBM) as an adjunctive treatment in Rett syndrome (RTT).

Background data: RTT is a severe X-linked neurodevelopmental disorder caused mainly by MECP2 variants, with limited disease-modifying therapies. tPBM delivers red-to-near-infrared light to the brain and shows promising effects in several neurocognitive and neuropsychiatric conditions.

Methods: We reviewed key cellular mechanisms of RTT, namely mitochondrial dysfunction, oxidative stress, neuroinflammation, and impaired synaptic plasticity, and summarized established bioenergetic, redox, anti-inflammatory, and neurotrophic actions of tPBM.

Results: The convergence between these pathways suggests that tPBM could partially compensate for bioenergetic and signaling abnormalities in RTT, acting as a multi-target, pathophysiology-informed neuromodulation strategy.

Conclusions: Although speculative, this mechanistic convergence supports prioritizing preclinical studies in Mecp2-deficient models and early-phase feasibility trials of tPBM in individuals with RTT.

Objective: To systematically evaluate the clinical efficacy, safety, and procedural outcomes of thulium fiber laser (TFL) compared to Holmium:YAG (Ho:YAG) in laser lithotripsy for urinary stones, based on a synthesis of randomized and comparative studies.

Materials and methods: This systematic review and meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. PubMed, Embase, Cochrane Library, and Scopus were searched for studies published between January 2010 and March 2025. Eligible studies included randomized controlled trials and cohort studies directly comparing TFL and Ho:YAG in ureteroscopy or retrograde intrarenal surgery (RIRS). Primary outcomes were stone-free rate (SFR), operative time, complication rate, and retreatment rate. Meta-analyses were performed using a random-effects model; heterogeneity was assessed using the I² statistic.

Results: Twenty-eight studies were included (7 RCTs, 21 cohort studies), encompassing a total of 3672 patients. TFL was associated with a significantly higher SFR (93.5% vs. 87.2%, p < 0.01), shorter operative time (43.2 vs. 52.8 min, p < 0.001), and lower retreatment rates (4.2% vs. 7.6%, p < 0.01). Complication rates were comparable between groups. Heterogeneity among studies was moderate (I² = 62%); subgroup analysis and sensitivity testing were used to explore sources of variability.

Conclusion: TFL demonstrates superior procedural outcomes compared to Ho:YAG in endourological management of urinary stones. Further research into next-generation systems-such as the Cyber Ho Magneto, which integrates high-power Ho:YAG output with TFL-like pulse modulation-may provide additional procedural benefits and warrants formal clinical evaluation.

Objective: To investigate the effectiveness of the acai photosensitizer (Euterpe oleracea Martius), combined or not with low-intensity laser, in reducing Streptococcus mutans in carious dentin.

Background: Due to its high penetration power and coloring ability, acai presents a promising and unexplored option for use as a photosensitizer in antimicrobial photodynamic therapy.

Methods: We selected 60 permanent third molars and exposed their coronal dentin. After producing dentin carious lesions, we randomly divided the teeth into four groups (n = 15 each): C (control)-no disinfection; AC (acai)-acai photosensitizer application; AC + BL (acai + laser)-acai photosensitizer application and irradiation with low-intensity blue laser diode (Therapy); and BL (laser)-low-intensity blue laser diode (Therapy) application. All carious tissue was collected post-protocol application. Total viable bacterial count was determined after 2 days of incubation. Micro-computed tomography was used for qualitative analysis of carious lesions through observation of a carious tooth (control group). Scanning electron microscopy (SEM) was used for qualitative analysis of carious tissue disinfection using different protocols. Results were analyzed using the Kruskal-Wallis test (Student-Newman-Keuls).

Results: The cariogenic challenge produced a carious lesion measuring 17.14875 mm³, located in deep dentin close to the pulp. The AC + BL group showed the most significant reduction in S. mutans count (p < 0.0001), followed by the AC group (p = 0.0055). The BL group showed no significant reduction in S. mutans count (p = 0.2122). SEM analysis showed that AC + BL promoted dentin disinfection, with exposed dentinal tubules. The percentage reduction in S. mutans count was: BL (35.75%), AC (63.41%), and AC + BL (92.68%).

Conclusions: The AC + BL group showed significantly better results than the AC group alone. The acai photosensitizer, with or without antimicrobial photodynamic therapy, is indicated for carious dentin disinfection.

Background: Photobiomodulation Valeda (PBM-Valeda) is a novel therapeutic approach for dry age-related macular degeneration (AMD). The primary objective of this short-term study was to conduct an analysis of best-corrected visual acuity (BCVA) and evaluate of biomarkers using state-of-the-art high-resolution imaging with swept-source optical coherence tomography OCT (SS-OCT) and OCT angiography (SS-OCTA) in dry AMD patients treated with PBM.

Materials and methods: This prospective, noncomparative, interventional case series pilot study examined the following biomarkers before and after PBM treatment: BCVA, central macular thickness (CMT), subfoveal choroidal thickness (SCT), capillary density (CD), avascular area of the superficial plexus (AASP), and avascular area of the deep plexus (AADP). All parameters were assessed at baseline and 1 week after treatment. A questionnaire (exploratory, not a validated endpoint) was carried out at the end of the treatment.

Results: The study included 25 eyes (19 patients), predominantly in the Age-Related Eye Disease Study category II. A statistically significant change in BCVA was observed (p = 0.001). No statistically significant changes were observed in CMT, SCT, CD, AASP, or AADP (p > 0.05). The treatment was well tolerated, with few mild side effects, and no patient developed wet AMD.

Conclusion: PBM-Valeda therapy demonstrated a favorable short-term safety profile in patients with dry AMD. The key finding of this study was the stability of SS-OCT and SS-OCTA biomarkers (CMT, SCT, CD, AASP, and AADP), with no adverse changes observed. These results reinforce the short-term safety of PBM. Reported side effects were minimal, with no evidence of retinotoxicity. This is the first prospective study to explore SS-OCT and SS-OCTA biomarkers in patients with dry AMD undergoing PBM therapy, providing preliminary safety data for future controlled trials.

Background: The combination of lasers and acoustic shock waves has shown promising results in accelerating tattoo removal.

Objective: To assess the effectiveness of treatments combining lasers and shock waves regarding the number of sessions required for successful tattoo removal.

Methods: A prospective, observational, real-world, single-center study including adults (>18 years) with ≥one professional tattoo of any color on any body part, excluding the head, partially removed or not. Devices were the QS laser RevLite® SI (Cynosure Lutronic, USA), the picosecond laser PicoWay® (Candela, USA), the CO₂ laser DUOGlide® with a SCAR 3 scanner (DEKA M.E.L.A. srl, Italy), and the GENTLE Pro® shock waves system (Zimmer MedizinSysteme GmbH, Germany). Treatment protocols consisted of QS/picosecond laser passes alternated with shock wave passes (three each) (classic protocol) and one QS/picosecond laser and one shock wave pass, a QS/picosecond second laser pass, and a final fractional CO₂ laser pass (reinforced protocol). Sessions were performed at two-month intervals.

Results: We included 22 patients (68.2% women and 68.2% Fitzpatrick phototype III) with a mean (range) age of 42 (22-68) years and 25 tattoos in total. Most tattoos were black (92.0%) and were removed using the picosecond laser (80.0%) and following the classic (40.0%) and the reinforced (60.0%) protocols in a total of 66 treatment sessions. In 22 tattoos undergoing more than one session, results were good or excellent in 68.2% of them after 2-4 sessions, with no adverse effects.

Conclusion: Acoustic shock wave therapy constitutes a safe adjuvant treatment to accelerate laser-based tattoo removal.

Background: Blepharoplasty rectifies functional and aesthetic problems of the periorbital area.

Objective: This study tests the effectiveness of a combined procedure of blepharoplasty and fractional ablative CO_2, resurfacing on a total of 16 patients diagnosed with dermatochalasis and surgical indication for upper blepharoplasty.

Methods: Patients underwent a combined procedure of blepharoplasty and fractional ablative CO₂ resurfacing. The examinations performed were: measurement of the height of the lacrimal meniscus, tear break-up time (FBUT), Schirmer test and Ocular Surface Disease Index questionnaire.

Results: All values returned to baseline 150 days (5 months) from surgery with improvement of the FBUT value. No significant change or worsening in values was observed after laser application and periorbital blepharoplasty.

Conclusions: The application of fractional CO₂ laser and blepharoplasty could lead to both psychological and social improvement in patients, reducing the potential risks that can lead to dry eye syndrome.