Fernanda H. Sakamoto

Fractional CO2 laser‐assisted drug delivery

Ablative fractional resurfacing (AFR) creates vertical channels that might assist the delivery of topically applied drugs into skin. The purpose of this study was to evaluate drug delivery by CO2 laser AFR using methyl 5‐aminolevulinate (MAL), a porphyrin precursor, as a test drug.

Photodynamic therapy for acne vulgaris: A critical review from basics to clinical practice: Part I. Acne vulgaris: When and why consider photodynamic therapy?

UNLABELLED The first-line treatments for acne vulgaris are conventional topical and/or oral medications. However, many patients have contraindications, only partial response, significant adverse effects, or recurrence. Light-based treatments and photodynamic therapy (PDT) using topical precursors of porphyrins are off-label alternative treatments for acne vulgaris, with their own advantages and disadvantages. To date, there is no consensus on PDT methodology and parameters. An understanding of pathophysiology of acne, light-tissue interactions, and PDT mechanisms of action is helpful whenever PDT is considered as an alternative treatment. In general, blue light alone improves acne because of its antiinflammatory effects. PDT using 5-aminolevulenic acid (ALA) or ALA derivatives induces transient antimicrobial and antiinflammatory effects. At high doses, red light PDT may induce inhibition or destruction of sebaceous glands, resulting in clinical improvement. LEARNING OBJECTIVES After completing this learning activity, participants should be able to compare different treatments of acne, recognize when photodynamic therapy may be a useful off-label treatment for acne vulgaris, and identify variables that may affect the efficacy of photodynamic therapy.

Enhanced uptake and photoactivation of topical methyl aminolevulinate after fractional CO2 laser pretreatment.

Photodynamic therapy (PDT) of thick skin lesions is limited by topical drug uptake. Ablative fractional resurfacing (AFR) creates vertical channels that may facilitate topical PDT drug penetration and improve PDT‐response in deep skin layers. The purpose of this study was to evaluate whether pre‐treating the skin with AFR before topically applied methyl aminolevulinate (MAL) could enable a deep PDT‐response.

Introduction to Confocal Microscopy

Conventional microscopy requires viewing a thin-cut “section” of fixed or frozen tissue, and therefore cannot be used to view thick tissue samples or for in vivo investigations. In vivo microscopy requires a virtual, rather than a physical, section of the specimen. Confocal microscopy, developed and patented by Marvin Minsky in 1955, uses optical imaging to create a virtual slice or plane, many micrometers deep, within the tissue. It provides very-high-quality images with fine detail and more contrast than conventional microscopy. In addition, the imaging technique allows for reconstruction of virtual 3-dimensional (3-D) images of the tissue when multiple sections are combined.

An elastic second skin

We report the synthesis and application of an elastic, wearable crosslinked polymer layer (XPL) that mimics the properties of normal, youthful skin. XPL is made of a tunable polysiloxane-based material that can be engineered with specific elasticity, contractility, adhesion, tensile strength and occlusivity. XPL can be topically applied, rapidly curing at the skin interface without the need for heat- or light-mediated activation. In a pilot human study, we examined the performance of a prototype XPL that has a tensile modulus matching normal skin responses at low strain (<40%), and that withstands elongations exceeding 250%, elastically recoiling with minimal strain-energy loss on repeated deformation. The application of XPL to the herniated lower eyelid fat pads of 12 subjects resulted in an average 2-grade decrease in herniation appearance in a 5-point severity scale. The XPL platform may offer advanced solutions to compromised skin barrier function, pharmaceutical delivery and wound dressings.

Three-dimensional volumetric quantification of fat loss following cryolipolysis

Cryolipolysis is a noninvasive and well‐tolerated treatment for reduction of localized subcutaneous fat. Although several studies demonstrate the safety and efficacy of this procedure, volumetric fat reduction from this treatment has not been quantified. This prospective study investigated the change in volume of fat after cryolipolysis treatment using three‐dimensional (3D) photography.

Safety and effectiveness of black tattoo clearance in a pig model after a single treatment with a novel 758 nm 500 picosecond laser: a pilot study.

Optimal selective photothermolysis of a pigment particle requires pulse durations equal to or less than the particles thermal relaxation time (t½). Since tattoo particles in skin range in diameter from 40 to 300 nm, picosecond pulses would approximate t½ more closely and, therefore, might be more effective at tattoo particle fragmentation.

Treatment of tattoo allergy with ablative fractional resurfacing: A novel paradigm for tattoo removal

BACKGROUND Q-switched lasers are the gold standard for tattoo treatment. Allergic tattoo reactions present a treatment dilemma. We present the application of ablative fractional resurfacing (AFR) as a novel method for tattoo removal. OBJECTIVE We describe two patients with tattoo allergies, referred to us for treatment. METHODS AFR was used in a series of treatments to remove the allergic-ink portion of a multicolored tattoo on the upper extremity of a 52-year-old man. In a 31-year-old woman with a red and black tattoo on her lower extremity, AFR was combined with a Q-switched neodymium:yttrium-aluminum-garnet laser. RESULTS After a series of treatments, both patients experienced significant to complete removal of the offending tattoo inks with substantial or complete resolution of their symptoms. LIMITATIONS This uncontrolled observational series is based on two patients. CONCLUSIONS AFR appears to be safe and effective for removal of allergic tattoos. AFR can be combined with other treatments such as Q-switched lasers. The potential for a series of AFR treatments to remove tattoos, including allergic tattoos and inks of any color, merits further study.

Dystrophic scrotal calcinosis originating from benign eccrine epithelial cysts

Scrotal calcinosis has been classified as a form of idiopathic calcinosis cutis. However, the pathogenesis of the calcified nodules has not been fully elucidated: it is still unclear whether the condition is truly idiopathic, or the result of breakdown of calcified epithelial cysts. We describe a 29‐year‐old Japanese patient with scrotal calcinosis originating from epithelial cysts. Light microscopy revealed a large epithelial cyst containing von Kossa‐positive material and several small dilated ductal structures beside the cyst. The epithelia of the cyst and ductal structures were connected, showing similar eccrine duct differentiation on immunohistochemical staining and electron microscopy. In the cyst lumen, calcium was present as needle‐shaped crystals. The pathogenetic mechanism of calcium deposition seemed to be due to excessive production and discharge of matrical debris and sulphated mucopolysaccharides, which derived from luminal cells, and their accumulation in the lumina.

Acne Treatment Based on Selective Photothermolysis of Sebaceous Follicles with Topically Delivered Light-Absorbing Gold Microparticles

The pathophysiology of acne vulgaris depends on active sebaceous glands, implying that selective destruction of sebaceous glands could be an effective treatment. We hypothesized that light-absorbing microparticles could be delivered into sebaceous glands, enabling local injury by optical pulses. A suspension of topically applied gold-coated silica microparticles exhibiting plasmon resonance with strong absorption at 800 nm was delivered into human pre-auricular and swine sebaceous glands in vivo, using mechanical vibration. After exposure to 10–50 J cm−2, 30 milliseconds, 800 nm diode laser pulses, microscopy revealed preferential thermal injury to sebaceous follicles and glands, consistent with predictions from a computational model. Inflammation was mild; gold particles were not retained in swine skin 1 month after treatment, and uptake in other organs was negligible. Two independent prospective randomized controlled clinical trials were performed for treatment of moderate-to-severe facial acne, using unblinded and blinded assessments of disease severity. Each trial showed clinically and statistically significant improvement of inflammatory acne following three treatments given 1–2 weeks apart. In Trial 2, inflammatory lesions were significantly reduced at 12 weeks (P=0.015) and 16 weeks (P=0.04) compared with sham treatments. Optical microparticles enable selective photothermolysis of sebaceous glands. This appears to be a well-tolerated, effective treatment for acne vulgaris.