Effect of quality-switched laser exposure in patients with history of edible gold consumption Abstract Injectable gold is known to deposit in the dermis for life, and such patients are at risk of developing chrysiasis post-laser exposure. It is unknown if patients with history of edible gold consumption would develop a similar reaction after quality-switched laser exposure. Our aim is to assess if patients with history of edible gold consumption develop chrysiasis after quality-switched laser exposure. This is a proof of concept pilot study conducted between September 2017 and September 2018 at two dermatology clinics in Riyadh, Saudi Arabia. Adult patients who have history of edible gold consumption were recruited to receive a spot test with different quality-switched lasers in a hidden, non-sun-exposed skin site. The test area was photographed before, immediately after, and 10 min after laser exposure. The test area was examined by two independent investigators for the development of chrysiasis. A total of 10 patients (five male and five female) were enrolled. The mean age was 31.7 years. Forty percent of subjects consumed edible gold more than once, and the duration of last intake ranged from 3 weeks to 3 months. Chocolate was the main source of edible gold. All participants had no chrysiasis reaction post-quality-switched laser exposure. Contrary to our hypothesis, all participants with history of short-term edible gold consumption did not develop chrysiasis after quality-switched laser exposure. Further controlled studies including more patients with longer duration and higher frequency of edible gold consumption are needed.

Combination laser therapy as a non-surgical method for treating congenital melanocytic nevi from cosmetically sensitive locations on the body

Photobiomodulation-induced analgesia in experimental temporomandibular disorder involves central inhibition of fractalkine Abstract Temporomandibular disorder (TMD) is a collective term that encompasses a set of clinical problems that affect the masticatory muscles, the temporomandibular joint, and associated structures. Despite their high clinical prevalence, the mechanisms of chronic craniofacial muscle pain are not yet well understood. Treatments for TMD pain relief and control should be minimally invasive, reversible, and conservative. Photobiomodulation (PBM) is a promising option once it is known to inhibit inflammatory response and to relief painful symptoms. Herein, the effects of PBM (660 nm, 30 mW, 16 J/cm2, 0.2 cm2, 15 s in a continuous frequency) on the pain sensitivity of rats submitted to an experimental model of TMD induced by CFA was evaluated. Experimental TMD was induced in rats by the injection of complete Freund’s adjuvant (CFA) injection into the masseter muscle. Nociceptive behavior was evaluated by electronic von Frey before CFA and after 1 h, 3 h, 6 h, and 24 h and 7, 14, and 21 days after PBM treatment. Inflammatory infiltrate was evaluated by histology of the masseter muscle and fractalkine expression was evaluated by immunohistochemistry of the trigeminal ganglia. PBM reversed the mechanical hypersensitivity of the animals by inhibiting the local inflammatory response, observed by the decrease of the inflammatory infiltrate in the masseter muscle of rats and by a central inhibition of fractalkine observed in the trigeminal ganglion. These data provide new insights into the mechanisms involved in the effects of photobiomodulation therapy emphasizing its therapeutic potential in the treatment of TMD.

Early intervention with pulse dye and CO 2 ablative fractional lasers to improve cutaneous scarring post-lumpectomy: a randomized controlled trial on the impact of intervention on final cosmesis Abstract Light-based modalities appear to be effective for ameliorating surgical scar appearance; however, protocols for achieving such outcomes have yet to be established. We studied the safety and efficacy of a combination of pulsed dye laser (PDL) and fractional ablative CO2 laser (FACL) for the attenuation of post-lumpectomy scarring. We conducted a prospective, evaluator-blinded, comparative split-scar study in post-lumpectomy patients. One-half of the scar was treated with three sessions of 595-nm PDL and FACL at 1-month intervals, starting within 6 weeks after suture removal. The entire scar was also treated with standard moisturizers and silicone gels. Six months after the last treatment, the two halves of the scar were assessed by three uninvolved physicians who used the Observer Scar Assessment Scale as well as by the patients who used the Patient and Observer Scar Assessment Scale. Eighteen female patients (mean age, 51.3 years) with a mean scar length of 7.8 cm completed the treatment and follow-up. Six months after the last treatment, both the physician evaluators and the patients noted significant improvements for all assessed scar parameters in the laser-treated scar area compared with the untreated scar area. The treatment was well tolerated, and no remarkable adverse events were reported. All 18 participants were satisfied with the treated scar areas. A combination PDL and FACL protocol starting up to 6 weeks after suture removal is a safe and effective method for the attenuation of post-lumpectomy scar formation.

Topical and intradermal delivery of PpIX precursors for photodynamic therapy with intense pulsed light on porcine skin model Abstract In order to purposely decrease the time of the photodynamic therapy (PDT) sessions, this study evaluated the effects of PDT using topical and intradermal delivery of two protoporphyrin (PpIX) precursors with intense pulsed light (IPL) as irradiation source. This study was performed on porcine skin model, using an IPL commercial device (Intense Pulse Light, HKS801). IPL effect on different administration methods of two PpIX precursors (ALA and MAL) was investigated: a topical cream application and an intradermal application using a needle-free, high-pressure injection system. Fluorescence investigation showed that PpIX distribution by needle-free injection was more homogeneous than that by cream, suggesting that a shorter drug-light interval in PDT protocols is possible. The damage induced by IPL-PDT assessed by histological analysis mostly shows modifications in collagens fibers and inflammation signals, both expected for PDT. This study suggested an alternative protocol for the PDT treatment, possibility half of the incubation time and with just 3 min of irradiation, making the IPL-PDT, even more, promising for the clinical treatment.

Application of temporal correlation algorithm to interpret laser Doppler perfusion imaging

A randomized, investigator-blinded, controlled, split-scalp study of the efficacy and safety of a 1550-nm fractional erbium-glass laser, used in combination with topical 5% minoxidil versus 5% minoxidil alone, for the treatment of androgenetic alopecia Abstract Fractional 1550-nm erbium-glass (Er:Glass) laser therapy is effective in inducing hair regrowth. Combining fractional Er:Glass laser therapy with topical minoxidil may yield therapeutic benefits for patients with androgenetic alopecia (AGA). To compare the efficacy and safety of fractional Er:Glass laser used in combination with topical 5% minoxidil versus 5% minoxidil alone for the treatment of male AGA, 30 men with AGA were randomized to 24 weeks of split-scalp treatment using fractional Er:Glass laser and 5% minoxidil on one side (combined therapy) or 5% minoxidil alone on the other side (monotherapy). The primary outcome was the difference in hair density and diameter, from baseline, between two treatment sides, at week 24. The secondary outcome was a global photographic assessment, evaluated by two dermatologists and the participants. Adverse events were evaluated. Twenty-nine participants completed the 24-week study period. Combination therapy provided significantly superior results for both the primary and secondary outcomes (all p < 0.05). No serious adverse events were identified for either treatment. In conclusion, combination therapy, consisting of fractional Er:Glass laser and topical minoxidil, is a promising treatment option for AGA. Laser-induced photothermolysis and the formation of effective routes for transdermal drug delivery are possible mechanisms. clinicaltrials.in.th, identifier TCTR20160912001

Label-free diagnosis of lung cancer with tissue-slice surface-enhanced Raman spectroscopy and statistical analysis Abstract Despite the rapid development of medical science, the diagnosis of lung cancer is still quite challenging. Due to the ultrahigh detection sensitivity of surface-enhanced Raman spectroscopy (SERS), SERS has a broad application prospect in biomedicine, especially in the field of tumor blood detection. Although Raman spectroscopy can diagnose lung cancer through tissue slices, its weak cross sections are problematic. In this study, silver nanoparticles (AgNPs) were added to the surface of lung tissue slices to enhance the Raman scattering signals of biomolecules. The electromagnetic field distribution of AgNPs prepared was simulated using the COMSOL software. SERS obtained from the slices reflected the difference in biochemical molecules between normal (n = 23) and cancerous (n = 23) lung tissues. Principal component-linear discriminate analysis (PCA-LDA) was utilized to classify lung cancer and healthy lung tissues. The receiver operating characteristic curve gave the sensitivity (95.7%) and specificity (95.7%) of the PCA-LDA method. This study sheds new light on the general applicability of SERS analysis of tissue slices in clinical trials.

Different photodynamic effects of blue light with and without riboflavin on methicillin-resistant Staphylococcus aureus (MRSA) and human keratinocytes in vitro Abstract Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of infections in humans. Photodynamic therapy using blue light (450 nm) could possibly be used to reduce MRSA on different human tissue surfaces without killing the human cells. It could be less harmful than 300–400 nm light or common disinfectants. We applied blue light ± riboflavin (RF) to MRSA and keratinocytes, in an in vitro liquid layer model, and compared the effect to elimination using common disinfection fluids. MRSA dilutions (8 × 105/mL) in wells were exposed to blue light (450 nm) ± RF at four separate doses (15, 30, 56, and 84 J/cm2). Treated samples were cultivated on blood agar plates and the colony forming units (CFU) determined. Adherent human cells were cultivated (1 × 104/mL) and treated in the same way. The cell activity was then measured by Cell Titer Blue assay after 24- and 48-h growth. The tested disinfectants were chlorhexidine and hydrogen peroxide. Blue light alone (84 J/cm2) eliminated 70% of MRSA. This dose and riboflavin eradicated 99–100% of MRSA. Keratinocytes were not affected by blue light alone at any dose. A dose of 30 J/cm2 in riboflavin solution inactivated keratinocytes completely. Disinfectants inactivated all cells. Blue light alone at 450 nm can eliminate MRSA without inactivation of human keratinocytes. Hence, a high dose of blue light could perhaps be used to treat bacterial infections without loss of human skin cells. Photodynamic therapy using riboflavin and blue light should be explored further as it may perhaps be possible to exploit in treatment of skin diseases associated with keratinocyte hyperproliferation.

Fractional carbon dioxide laser and topical tioconazole in the treatment of fingernail onychomycosis Abstract Onychomycosis is a common chronic-resistant nail disease. Traditional treatment has its limitations and side effects. This study aimed to evaluate the role of fractional CO2 laser and topical tioconazole 28% nail lacquer in the treatment of fingernail onychomycosis, as sole treatment modalities and in combination. Thirty patients with culture-proven onychomycosis were included and randomly divided into three equal groups. Laser group received six fractional carbon dioxide (CO2) laser sessions at monthly intervals; topical group received topical tioconazole 28% nail lacquer twice daily for 6 months, and combined group received six fractional CO2 laser sessions at monthly intervals with topical tioconazole twice daily for 6 months. Treatment outcome was evaluated through physician’s evaluation of improvement using onychomycosis severity index score (OSI), patients’ satisfaction, side effect evaluation, and mycological culture (assessed after the end of treatment). At the end of treatment, both laser and combined groups showed significantly better degrees of improvement (P = 0.036, 0.024, respectively) and patient’s satisfaction (P = 0.046, 0.003, respectively) in comparison with topical group. Mycological clearance in fungal cultures was significantly higher in combined group than topical group after the end of treatment (P = 0.007). Fractional CO2 laser is a safe and effective treatment modality for onychomycosis. Its efficacy approximates that of fractional CO2 laser combined with topical tioconazole 28% nail lacquer and surpasses that of topical tioconazole 28% monotherapy. It is expected to be an excellent choice for patients in whom systemic antifungals are contraindicated or who are unresponsive or intolerant to topical antifungals.