Paradoxical adipose hyperplasia after cryolipolysis

IMPORTANCE

Cryolipolysis is the noninvasive reduction of fat with localized cutaneous cooling. Since initial introduction, over 650,000 cryolipolysis treatment cycles have been performed worldwide. We present a previously unreported, rare adverse effect following cryolipolysis: paradoxical adipose hyperplasia.

OBSERVATIONS

A man in his 40s underwent a single cycle of cryolipolysis to his abdomen. Three months following his treatment, a gradual enlargement of the treatment area was noted. This enlargement was a large, well-demarcated subcutaneous mass, slightly tender to palpation. Imaging studies revealed accumulation of adipose tissue with normal signal intensity within the treatment area.

CONCLUSIONS AND RELEVANCE

Paradoxical adipose hyperplasia is a rare, previously unreported adverse effect of cryolipolysis with an incidence of 0.0051%. No single unifying risk factor has been identified. The phenomenon seems to be more common in male patients undergoing cryolipolysis. At this time, there is no evidence of spontaneous resolution. Further studies are needed to characterize the pathogenesis and histologic findings of this rare adverse event.

Three-dimensional volumetric quantification of fat loss following cryolipolysis

BACKGROUND AND OBJECTIVES

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.

MATERIALS AND METHODS

A prospective study of subjects treated with cryolipolysis on the flank (love handle) was performed at Massachusetts General Hospital. Volume measurements were performed with a Canfield Scientific Vectra three-dimensional camera and software to evaluate the amount of post procedure volume change. Clinical outcomes were assessed with caliper measurements, subject surveys, and blinded physician assessment of photographs.

RESULTS

Eleven subjects were enrolled in this study. Each subject underwent a single cycle of cryolipolysis to one flank. The untreated flank served as an internal control. The follow-up time after treatment was 2 months. The mean amount of calculated absolute fat volume loss using 3D photography from baseline to 2 months follow-up visit was 56.2 ± 25.6 from the treatment site and 16.6 ± 17.6 cc from the control (P < 0.0001). A mean absolute difference of 39.6 cc between the treated and untreated sides was calculated at 2 months post-treatment. Comparison of caliper measurements from baseline to 2 months post-treatment demonstrated significant reduction of the treated flank from 45.6 ± 5.8 mm at baseline to 38.6 ± 4.6 mm at 2 months post-treatment (P < 0.001). The untreated flank did not show significant reduction with caliper measurements demonstrating 45.3 ± 5.0 mm at baseline and 44.6 ± 5.1 mm at 2 months post-treatment (P = 0.360). No unexpected side effects or adverse events were reported. Post-treatment satisfaction surveys demonstrated 82% of subjects were satisfied with the results.

CONCLUSIONS

Cryolipolysis is a safe, well-tolerated, and effective noninvasive fat removal methodology that on average leads to 39.6 cc of fat loss of the treated flank at 2 months after a single treatment cycle.

Fractional laser-assisted delivery of methyl aminolevulinate: Impact of laser channel depth and incubation time

BACKGROUND AND OBJECTIVES

Pretreatment of skin with ablative fractional lasers (AFXL) enhances the uptake of topical photosensitizers used in photodynamic therapy (PDT). Distribution of photosensitizer into skin layers may depend on depth of laser channels and incubation time. This study evaluates whether depth of intradermal laser channels and incubation time may affect AFXL-assisted delivery of methyl aminolevulinate (MAL).

MATERIALS AND METHODS

Yorkshire swine were treated with CO2 AFXL at energy levels of 37, 190, and 380 mJ/laser channel and subsequent application of MAL cream (Metvix) for 30, 60, 120, and 180 minutes incubation time. Fluorescence photography and fluorescence microscopy quantified MAL-induced porphyrin fluorescence (PpIX) at the skin surface and at five specific skin depths (120, 500, 1,000, 1,500, and 1,800 µm).

RESULTS

Laser channels penetrated into superficial (∼300 µm), mid (∼1,400 µm), and deep dermis/upper subcutaneous fat layer (∼2,100 µm). Similar fluorescence intensities were induced at the skin surface and throughout skin layers independent of laser channel depth (180 minutes; P < 0.19). AFXL accelerated PpIX fluorescence from skin surface to deep dermis. After laser exposure and 60 minutes MAL incubation, surface fluorescence was significantly higher compared to intact, not laser-exposed skin at 180 minutes (AFXL-MAL 60 minutes vs. MAL 180 minutes, 69.16 a.u. vs. 23.49 a.u.; P < 0.01). Through all skin layers (120-1,800 µm), laser exposure and 120 minutes MAL incubation induced significantly higher fluorescence intensities in HF and dermis than non-laser exposed sites at 180 minutes (1,800 µm, AFXL-MAL 120 minutes vs. MAL 180 minutes, HF 14.76 a.u. vs. 6.69 a.u. and dermis 6.98 a.u. vs. 5.87 a.u.; P < 0.01).

CONCLUSIONS

AFXL pretreatment accelerates PpIX accumulation, but intradermal depth of laser channels does not affect porphyrin accumulation. Further studies are required to examine these findings in clinical trials.

The impact of treatment density and molecular weight for fractional laser-assisted drug delivery

Ablative fractional lasers (AFXL) facilitate uptake of topically applied drugs by creating narrow open micro-channels into the skin, but there is limited information on optimal laser settings for delivery of specific molecules. The objective of this study was to investigate the impact of laser treatment density (% of skin occupied by channels) and molecular weight (MW) for fractional CO(2) laser-assisted drug delivery. AFXL substantially increased intra- and transcutaneous delivery of polyethylene glycols (PEGs) in a MW range from 240 to 4300 Da (Nuclear Magnetic Resonance, p<0.01). Increasing laser density from 1 to 20% resulted in augmented intra- and transdermal delivery (p<0.01), but densities higher than 1% resulted in reduced delivery per channel. Mass spectrometry indicated that larger molecules have greater intracutaneous retention than transcutaneous penetration. At 5% density, median delivery of PEGs with mean MW of 400, 1000, 2050 and 3350 Da were respectively 0.87, 0.31, 0.23 and 0.15 mg intracutaneously and 0.72, 0.20. 0.08 and 0.03 mg transcutaneously, giving a 5.8- and 24.0-fold higher intra- and transcutaneous delivery of PEG400 than PEG3350 (p<0.01). This study substantiates that fractional CO(2) laser treatment allows uptake of small and large molecules into and through human skin, and that laser density can be varied to optimize intracutaneous or transcutaneous delivery.

Intensified photodynamic therapy of actinic keratoses with fractional CO2 laser: a randomized clinical trial

BACKGROUND

Photodynamic therapy (PDT) with methyl aminolaevulinate (MAL) is effective for thin actinic keratoses (AKs) in field-cancerized skin. Ablative fractional laser resurfacing (AFXL) creates vertical channels that facilitate MAL uptake and may improve PDT efficacy.

OBJECTIVES

To evaluate efficacy and safety of AFXL-assisted PDT (AFXL-PDT) compared with conventional PDT in field-directed treatment of AK.

METHODS

Fifteen patients with a total of 212 AKs (severity grade I-III) in field-cancerized skin of the face and scalp were randomized to one treatment with PDT and one treatment with AFXL-PDT in two symmetrical areas. Following curettage of both treatment areas, AFXL was applied to one area using 10 mJ per pulse, 0·12 mm spot, 5% density, single pulse (UltraPulse(®), DeepFx handpiece; Lumenis Inc., Santa Clara, CA, U.S.A.). MAL cream was then applied under occlusion for 3 h and illuminated with red light-emitting diode light at 37 J cm(-2). Fluorescence photography quantified protoporphyrin IX (PpIX) before and after illumination.

RESULTS

At 3-month follow-up, AFXL-PDT was significantly more effective than PDT for all AK grades. Complete lesion response of grade II-III AK was 88% after AFXL-PDT compared with 59% after PDT (P = 0·02). In grade I AK, 100% of lesions cleared after AFXL-PDT compared with 80% after PDT (P = 0·04). AFXL-PDT-treated skin responded with significantly fewer new AK lesions (AFXL-PDT n = 3, PDT n = 11; P = 0·04) and more improved photoageing (moderate vs. minor improvement, P = 0·007) than PDT-treated skin. Pain scores during illumination (6·5 vs. 5·4; P = 0·02), erythema and crusting were more intense, and long-term pigmentary changes more frequent from AFXL-PDT than PDT (P = not significant). PpIX fluorescence was higher in AFXL-pretreated skin [7528 vs. 12,816 arbitrary units (AU); P = 0·003] and photobleached to equal intensities after illumination (AFXL-PDT 595 AU, PDT 454 AU; P = 0·59).

CONCLUSIONS

AFXL-PDT is more effective than conventional PDT for treatment of AK in field-cancerized skin.

Intracutaneous ALA photodynamic therapy: dose-dependent targeting of skin structures

BACKGROUND

Photodynamic therapy (PDT) using topical aminolevulinic acid (ALA) depends on local drug uptake, metabolism to porphyrins, and depth of light penetration using different wavelengths. Topical ALA-PDT has limited depth of drug penetration. We studied induced porphyrin distribution and PDT after intradermal ALA administration using different drug concentrations followed by high-fluence red light irradiation.

MATERIALS AND METHODS

Intradermal injections (∼2 mm deep) of ALA concentrations from 0.0005% to 1% were studied in swine to evaluated porphyrin fluorescence before PDT and clinical and histological damage 24 hours after PDT. Porphyrin accumulation was measured by fluorescence microscopy of frozen section. PDT was performed 3 hours after intradermal injections using a 635 nm LED array at a fluence of 200 J/cm2 . Skin responses to PDT were observed grossly and by histology (blind evaluation).

RESULTS

Intradermal ALA caused porphyrin accumulation in epidermis, hair follicles (HF), sebaceous glands (SG), sweat glands (eccrine glands, EG and apocrine glands, AG), and subcutaneous fat. Significant differences of fluorescence intensity were observed between different skin structures (P < 0.05), but there was no significant difference comparing HF to SG; epidermis with either HF or SG; and dermis with fat (P > 0.05). Intradermal ALA is potent. ALA concentrations ≥0.25% followed by red light exposures caused a very intense vascular PDT reaction. Moderate doses of injected ALA concentration (∼0.06%), selectively targeted EG. Low doses (≤0.016%) targeted fat; producing fat necrosis with minimal inflammation, manifested both clinically and histologically. In contrast to topical ALA-PDT, intradermal ALA-PDT can effectively photosensitize deep skin structures.

CONCLUSION

Potentially, intradermal ALA-PDT using various ALA concentrations may be useful for treating vascular lesions (malformations, hemangiomas, tumors), EG/AG disorders, fat or deep targets in skin.

Polarization-sensitive optical coherence tomography imaging of benign and malignant laryngeal lesions: an in vivo study

OBJECTIVE

Optical coherence tomography (OCT), an imaging technology that provides cross-sectional subsurface tissue structure images using back-scattered light, is a promising noninvasive imaging modality for in vivo assessment of vocal fold layered microstructure. Polarization-sensitive OCT (PS-OCT) augments conventional OCT by detecting changes in the polarization state of reflected light. This study imaged various benign and malignant laryngeal pathologies in patients undergoing direct laryngoscopy under general anesthesia to determine whether PS-OCT would provide useful additional information about vocal fold microstructure and glottic surface pathology. STUDY DESIGN. Prospective clinical trial.

SETTING

Tertiary care center.

SUBJECTS AND METHODS

Twenty-three patients who were undergoing microlaryngoscopy under general anesthesia for benign (n = 18) and alignant (n = 5) glottic disease were imaged bilaterally with OCT and PS-OCT (n = 46 vocal folds). Intraoperative microphotography guided placement of the imaging probe. Normal-appearing glottic tissue was also imaged if present. When clinically indicated, biopsy or complete removal of the lesion established histologic confirmation.

RESULTS

PS-OCT provided high-quality, vertical, cross-sectional images up to 1.2-mm deep that complemented microlaryngoscopy and conventional OCT for vocal fold pathologies. Scar tissue was visualized by PS-OCT, characterized by a birefringence pattern more intense than that of normal glottic tissue. Cancer typically showed disruption or absence of both layered structure and birefringence.

CONCLUSION

Combining PS-OCT with OCT during human vocal cord imaging provides useful information in characterizing vocal cord lesions, articularly scar tissue.

755 nm alexandrite laser for the reduction of tumor burden in basal cell Nevus syndrome

BACKGROUND AND OBJECTIVE

Basal Cell Nevus syndrome (BCNS) is characterized by numerous basal cell carcinomas (BCCs). Multiple treatments with the pulsed dye laser (PDL) have been shown, in small studies, to be effective for the treatment of superficial and nodular BCCs. Like PDL, the alexandrite laser can be vessel-selective, but has the added advantage of deeper tissue penetration. We evaluated the utility of the alexandrite laser in reducing the tumor burden in BCNS with a single treatment.

STUDY DESIGN/MATERIALS AND METHODS

A case report and review of the literature are presented. A 45-year-old man with BCNS and a history of radiation therapy presented with an extraordinarily high tumor burden (>250 BCCs). As a compassionate measure to reduce the tumor burden, we investigated the utility of a single treatment of the long-pulsed 755 nm alexandrite laser to several BCC lesions. The treated lesions were evaluated at 2-month and 7-month clinical follow-up. Histopathologic analysis of a treated lesion was performed at 7-month clinical follow-up.

RESULTS

At 2-month, and 7-month clinical follow-up, 15 of 18 treated lesions or about 83% of the alexandrite laser treated lesions showed a complete clinical response and appeared as hypopigmented areas with scarring. Histopathologic analysis of a treated lesion at 7-month clinical follow-up showed no evidence of residual tumor.

CONCLUSIONS

The long-pulsed alexandrite laser may be helpful in significantly reducing tumor burden in difficult to manage BCNS patients with a single treatment. This provides a facile and practical treatment alternative for the management of challenging cases of BCNS. The limitation of this study is that it is a single case observation. Larger, prospective studies are needed to confirm these observations.

Nanoparticles reduce nickel allergy by capturing metal ions

Approximately 10% of the population in the USA suffer from nickel allergy, and many are unable to wear jewellery or handle coins and other objects that contain nickel. Many agents have been developed to reduce the penetration of nickel through skin, but few formulations are safe and effective. Here, we show that applying a thin layer of glycerine emollient containing nanoparticles of either calcium carbonate or calcium phosphate on an isolated piece of pig skin (in vitro) and on the skin of mice (in vivo) prevents the penetration of nickel ions into the skin. The nanoparticles capture nickel ions by cation exchange, and remain on the surface of the skin, allowing them to be removed by simple washing with water. Approximately 11-fold fewer nanoparticles by mass are required to achieve the same efficacy as the chelating agent ethylenediamine tetraacetic acid. Using nanoparticles with diameters smaller than 500 nm in topical creams may be an effective way to limit the exposure to metal ions that can cause skin irritation.

Cell-cycle-dependent active thermal bystander effect (ATBE)

OBJECTIVE

To determine whether the active thermal bystander effect (ATBE) is cell-cycle dependent.

MATERIALS AND METHODS

Dividing cells were directly heated for 10 minutes and co-cultured for 24 hours with different bystander cells. We compared the ATBE for dividing and non-dividing human fibroblasts, as well as for dividing human white preadipocytes (HWP) and non-dividing, mature differentiated human white adipocytes. ATBE was assessed as loss of cell viability of the bystander cells by using the MTT assay. Cell-cycle analysis was performed by using flow cytometry.

RESULTS

Dividing fibroblasts and preadipocytes showed a significant ATBE (P < 0.008 and P < 0.05) with loss of cell viability of about 10% in the temperature range of 40-48°C. There was no significant difference between the extent of the bystander effect for these two cell populations (P = 0.30). In contrast, non-dividing fibroblasts and mature adipocytes did not generate any ATBE within this temperature range. There was a statistically significant difference in ATBE between dividing and non-dividing cell subpopulations for both fibroblasts (P = 0.003) and preadipocytes (P < 0.001) compared to their non-dividing counterparts.

CONCLUSION

These results suggest that the ATBE is a cell-cycle-dependent process which requires actively dividing cells as receiving bystander cells. The cell-cycle dependency of the ATBE could have useful clinical applications in selectively targeting fast growing cells such as tumor cells. Whether the yield of the ATBE can be amplified by synchronizing the exposure to the ATBE with specific phases of the cell cycle remains subject to further investigation.