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Yokohama-shi, Japan

Omi T.,Queens Square Medical Center | Omi T.,Nippon Medical School | Kawana S.,Nippon Medical School | Sato S.,Nippon Medical School | Naito Z.,Nippon Medical School
Laser Therapy | Year: 2013

Background and Aims: The pulsed dye laser (PDL) is recognized both as an effective treatment for vascular malformations and the as first treatment of choice for these lesions. However, PDL irradiation has poor efficacy in some patients, particularly the elderly. The present study histologically assessed such patients to try to elucidate the reason. Materials and Methods: A pulsed dye laser was used in 3 subjects in whom previous laser treatment was ineffective. Three-millimeter punch biopsies were obtained before laser treatment, 1 week and 3 months after the laser treatment. Each specimen was stained with toluidine blue and examined under light microscopy followed by electron microscopy with oolong tea extract (OTE) staining. Results: Microscopy revealed an increase in the vasculature at baseline and an increased number of dermal fibroblasts. One week post-irradiation, inflammatory cell infiltration was observed together with extensive interstitial perivascular edema. At 1 week and 3 months after laser irradiation, normal structures were observed for both blood vessels and capillary endothelial cells. Mild changes were noted in other interstitial features, but findings obtained 3 months after irradiation were almost similar to those before irradiation. Conclusions: The lower efficacy of PDL treatment in the elderly was possibly due to the markedly low amount of red blood cells in our subjects' blood vessels, a major chromophore for the PDL, was markedly low. It is possible that age-related denaturation of dermal matrix collagen plays some role in maintaining the vasculature in the interstitium with edema, and inflammatory cell infiltration could lead to the cellular release of some cytokines which favor reconstruction of the vasculature. © 2013 JMLL, Tokyo, Japan. Source

Omi T.,Queens Square Medical Center | Omi T.,Nippon Medical School | Sato S.,Nippon Medical School | Kawana S.,Nippon Medical School
Laser Therapy | Year: 2013

Introduction and Aims: Cellulite is a problematic condition affecting mostly women, characterized by a bumpy or nodular skin surface. Recent approaches with laser treatment have offered some promise. The present study sought to identify possible targets for laser treatment or light therapy through an ultrastructural investigation of the condition. Subjects and Methods: Study subjects comprised 7 healthy Japanese female volunteers (Age range 37-46 yr, average 38.4) with cellulite, graded on the 4-point Nurnberger-Muller cellulite severity scale. Four patients were at grade 2 and 3 at grade 3. Three millimeter punch biopsies were obtained and routinely processed for light and transmission electron microscopy. Results: Microphotography of specimens from cellulite patients demonstrated the presence of fibrotic septa which divided up larger clusters of adipose tissue into smaller packets, with the septa acting as a tethering system, thus producing the typical dimpling pattern. Ultrastructural findings showed proliferation of collagen and elastic fibers down into the cellulite tissue with compression of capillaries and congestion of arterioles, resulting in poor blood flow. Conclusions: The histological and ultrastructural findings of cellulite clearly distinguish the condition from simple fat deposition. The remodeling of the fat layer into lobulated packets of lipocytes sequestered by fibrotic septa with a high proportion of elastic fibers would suggest the use of a fiber-based interstitial laser-assisted lipolysis system at an appropriate wavelength which might offer benefits through disruption of the septae through a photomechanical effect and lipolysis of the sequestered lipocytes. This could be followed by a course of near-infrared phototherapy to accelerate clearance of freed lipid and debris and reestablish the vascular system. © 2013 JMLL, Tokyo, Japan. Source

Omi T.,Queens Square Medical Center | Omi T.,Nippon Medical School | Kawana S.,Nippon Medical School | Sato S.,Nippon Medical School | Naito Z.,Nippon Medical School
Journal of Cosmetic and Laser Therapy | Year: 2010

Background and objective: A variety of laser or light-based devices have been developed for skin rejuvenation. This study evaluates the efficacy (at the microscopic level) of a combination of pneumatic energy, broadband light, and profusion tip-delivered epidermal growth factor (EGF). Methods: Healthy adult Japanese volunteers were recruited for this study. The posterior parts of the left and right arms were treated with a device that combines pneumatic energy and broadband light (Isolaz device). The left arms were also treated with EGF through a tip. Each subject received four treatments at 10-day intervals. Biopsy specimens obtained 3 weeks after the second treatment and 3 weeks after the fourth treatment were examined for histological study. Results: After two treatments, elastin fibers and fibroblasts in the dermal papillary layers of the left arms were increased compared to the right arms. A mean of 173.9 cells positive for proliferating cell nuclear antibody (PCNA) were observed on the left arm compared to 101.0 on the right arm. After the fourth treatment, angiogenesis and increased collagen fibers were observed in the dermal papillary layers of both arms. Conclusion: Four treatments with the addition of the profusion tip appear to hasten new collagen and elastin fiber formation, and the increase of PCNA positive cells so that dermal remodeling begins at an earlier stage than with the Isolaz alone. © 2010 Informa UK, Ltd. Source

Omi T.,Queens Square Medical Center | Omi T.,Nippon Medical School | Yamashita R.,Shonan Kamakura General Hospital | Kawana S.,Nippon Medical School | And 2 more authors.
Laser Therapy | Year: 2012

Background: Melasma still presents as a difficult entity to treat, especially in the Asian skin phenotype. Recently laser toning with the Q-switched Nd:YAG has attracted attention. The present study investigated the efficacy of Q-switched Nd:YAG laser toning for melasma, with a histopathological comparison with the Q-switched ruby laser. Subjects and Methods: Eight Japanese females (41-57 yr, mean 52.5 yr) with Fitzpatrick skin type III and bilateral melasma participated in the study. One half of each subject's face (randomly chosen) was treated with Q-switched 1064 nm Nd:YAG laser toning (pulse width 5-20 ns; spot size, 6 mm diameter; fluence, 3.0 J/cm 2, 5-7 passes, once/week, 4 weeks: QS:YAG group), and the contralateral half with a single treatment using a Q-switched ruby laser (694.5 nm, pulse width 20 ns, spot size 4 mm diameter; fluence 4.0 J/cm 2, 1 pass with approximately 20% overlap: QS:Ruby group). Skin biopsies were taken immediately after the 4th Nd:YAG session and the single ruby session, and histopathological comparison was performed with light- and transmission electron microscopy (TEM). Results: Improvement in melasma pigmentation was seen in both the QS:YAG- and QS:Ruby-treated sides, and this was well-maintained in the QS:YAG group. Ultrastructurally, melanin granules were destroyed in both groups, but there was considerably more morphological epidermal and dermal damage in the QS:Ruby specimens compared with minimal epidermal disruption and cellular damage in the QS:YAG specimens. Conclusions: Q-switched 1064 nm Nd:YAG laser toning offered superior results in the treatment of melasma in the Japanese skin type compared with the Q-switched ruby laser, both ultrastructurally with less immediately post-treatment cellular damage and macroscopically, and a longer recurrence-free interval. © 2012 JMLL, Tokyo, Japan. Source

Omi T.,Queens Square Medical Center | Omi T.,Nippon Medical School | Kawana S.,Nippon Medical School | Sato S.,Nippon Medical School | And 2 more authors.
Journal of Cosmetic Dermatology | Year: 2011

Background Numerous reports have been published on skin rejuvenation by the so-called fractional laser device that delivers a laser beam in a dot form over a grid pattern. Aims In this study, we characterized the effects of a fractional CO2 laser on atrophic acne scars at the clinical and ultrastructural levels. Methods Seven healthy adult Japanese volunteers (aged 32-46years, mean 37.6, five men and two women of Fitzpatrick skin typeIII) were recruited for this study. A fractional CO2 laser device, SmartXide DOT (DEKA, Florence, Italy), was used with irradiation parameters set as follows: output power 10W, pulse width 600μs, dot spacing 800μm, and stack2 (irradiation output power 0.91J/cm2). A clinical examination and punch biopsy of each subject was performed before and just after the irradiation, and also at week3 after three irradiation sessions. The biopsy specimens were stained with toluidine blue and were examined ultrastructurally. Results Clinical improvement of the atrophic acne scars was observed at week3 after the third irradiation session in all cases compared with the condition before treatment. Histologically, outgrowths of many degenerated elastic fibers were observed as irregular rod-shaped masses in the superficial dermis prior to the treatment in the region of the acne scars. At week3 after the third irradiation, the degenerated elastic fibers were no longer observed, and the elastic fibers were elaunin-like. Conclusions The fractional CO2 laser is considered to be very effective for treating atrophic acne scars. © 2011 Wiley Periodicals, Inc. Source

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