BACKGROUND: Polymicrobial colonization and resultant biofilm formation significantly impair the process of wound healing. Stagnant tissue repair processes predispose patients to serious complications including systemic infection and limb amputation. Continuous Low-Irradiance Phototherapy (CLIP) is a novel therapeutic approach that delivers blue light at low irradiance for extended periods of time. Bench and preclinical work in the literature indicates that 405 nm light avoids thermal injury of healthy tissue, promotes a cytokine milieu favoring re-epithelialization and angiogenesis, and prevents bacterial and biofilm growth. Objective: This is the first in-human evaluation of a technology that delivers continuous low-irradiance 405 nm light to chronic wounds. The objective of this study was to determine the safety, feasibility, and ergonomics of this device for the treatment of chronic wounds in adult human subjects. This was not a randomized study to determine device efficacy, although data on outcome were collected. METHODS: In this prospective observational pilot study, participants received the intervention 24 hours per day, 7 days per week, for 4 weeks. Cohort I was conducted from December 2018 to March 2019, with Cohorts II and III ongoing. 25 study participants were recruited by referral (Cohort I: 5 participants, Cohort II: 10 participants, Cohort III: 10 participants). Our primary endpoint was to monitor for safety, assess usability by nurses and physicians, and evaluate patient comfort. The secondary endpoint, although not randomized nor directly compared with standard intervention, was the percentage area reduction (PAR) of the wound. Results: No adverse events or subject discomfort occurred with the CLIP intervention. The staff treating the study participants reported no ergonomic or compliance issues with the use of the device. The device received high scores in categories assessing practicality and ease of use. There was an average PAR of 29% (SD = 0.42). Conclusion: This study serves as the first in-human evaluation of extended low-irradiance 405 nm light for chronic wound therapy. The device appears safe and easy to use and had no compliance issues in the outpatient setting. Study participants who received CLIP without interruption saw either partial or complete reduction in wound area. J Drugs Dermatol. 2023;22(11):1111-1117 doi:10.36849/JDD.7206.
Light , Phototherapy , Adult , Humans , Pilot Projects , Prospective Studies , Phototherapy/adverse effects , Cytokines
Background: Ultrasound integration in undergraduate medical education (UME) has been a focused endeavor in recent years. According to the American Institute of Ultrasound in Medicine, more than a third of all US medical schools have adopted a focused ultrasound training program for medical students. Medical student perspectives on best practices in ultrasound education are lacking in the literature. Curricula Experiences: Two students' reflections are presented regarding two different didactic approaches, flipped classroom and self-study learning models, to teaching ultrasound in the pre-clinical medical education curriculum. Students present reflections on these didactic approaches to facilitate further improvement in ultrasound education curricula. Discussion: The self-directed learning model enabled students to learn foundational ultrasound exam techniques efficiently in a low-stress environment and subsequently optimized the efficiency of later faculty-led learning events. However, we noted that in both the flipped classroom and self-study learning models of education, the training on basic physical properties of ultrasound, tissue characteristics, and probe manipulation was limited. Conclusion: A self-study learning model ultrasound curricula improves perceived learning efficiency and student confidence, especially when followed by faculty-guided didactics and scanning opportunities. We suggest a framework for ultrasound education curricula that includes components of both formats of ultrasound education alongside faculty-led sessions as an ideal model of ultrasound education. Further, we propose the added benefit of inanimate object scanning to optimize students' knowledge of waveform physics (image acquisition and physical properties of materials) early in the ultrasound education process.
Pediatric post-operative abdominal pain can present a unique diagnostic challenge. The case presented here describes a 9-year-old female who presented with fever and worsening abdominal pain 4 days after laparoscopic resection of a benign ovarian teratoma. Computed tomography failed to provide adequate diagnostic imaging. Ultrasound was subsequently used to rule-out a major post-operative complication and ultimately led to a successful non-operative approach while avoiding repeat radiation exposure. Thin body habitus, increased radiosensitivity of pediatric organs, and increased lifetime risk of cancer complicate the use of computed tomography in the pediatric population. Ultrasound, when correlated to clinical findings, has unique advantages over CT such as detailed delineation of soft tissue structures and dynamic assessment of anatomy that make it advantageous in the pediatric post-operative setting.
Objective: The objective of this study is to report on the bactericidal effects of blue light administered at low irradiance for extended periods of time. Background: Multidrug-resistant organisms (MDROs) utilize biofilms that can limit the efficacy of antibiotics, causing infection and impaired wound healing. Unlike high-energy systems, continuous low-irradiance phototherapy (CLIP) avoids thermal injury of healthy tissue and can be delivered for extended periods. Methods: Four MDRO species, two of which contained different antibiotic resistance genes, were exposed to 405 nm irradiation in vitro. The microbes were incrementally exposed to increasing dose-rates (irradiance; mW/cm2) over a 24-h time period. Cell viability and biomass reduction assays were conducted to quantify the antibacterial/antibiofilm effects. Primary human dermal fibroblasts were also exposed to CLIP to assess whether these dose-rates would impair cell viability or proliferation. Results: CLIP exposure utilizing irradiances as low as 2.78 mW/cm2 delivered over 24 h resulted in a >3.0-log (>99.9%) and >2.0-log (>99.0%) microbial load reduction when organisms were grown in planktonic and biofilm-encapsulated conditions, respectively. Crystal violet biofilm assays revealed destruction of extracellular biofilm architecture following CLIP exposure. Human fibroblast viability and proliferation were unaffected by CLIP. Conclusions: This is the first report demonstrating the antimicrobial efficacy of CLIP for MDROs found in infected wounds. CLIP did not compromise cultured human fibroblast growth and survival. This study demonstrated that very low fluence rates (irradiances) delivered over extended periods are potently antimicrobial. There is translational potential for CLIP to be fabricated as a wearable device that would enable continuous ambulatory care of wounds.
Anti-Infective Agents , Drug Resistance, Multiple, Bacterial , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Gentian Violet , Humans , Phototherapy
Aortoenteric fistula is a rare complication after endovascular stent grafting. In the present report, we have described the case of a 69-year-old man 3 years after endovascular repair of an abdominal aortic aneurysm who had presented with worsening back pain and fever. Computed tomography had demonstrated dilated bowel and a thickened aortic wall, with air foci within the native aneurysm sac. He underwent emergent right axillary-bifemoral bypass with explantation of the aortic endograft and primary repair of the duodenal fistula. Tissue cultures grew Streptococcus anginosus, Prevotella denticola, and Parvimonas micra, and he was discharged home with 6 weeks of intravenous ceftriaxone and oral metronidazole after an 18-day hospital admission.
