The Effects of Aesthetic Lasers on Three Study Materials Used for Ocular Protection.

BACKGROUND: It is dangerous, although not uncommon, in some clinical settings for laser operators to place gauze underneath external patient protective eyewear when performing laser procedures. OBJECTIVES: The purpose of this study was to evaluate 4 lasers, commonly used for aesthetic facial procedures, on 3 materials commonly found in the clinical setting. METHODS: We performed tests with 4 lasers: the 2940-nm erbium-doped yttrium aluminum garnet (Er:YAG) laser, the 532-nm potassium titanyl phosphate (KTP) laser, the 1064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, and a Lumenis UltraPulse 10,600-nm carbon dioxide (CO2) laser. Their effects were evaluated on dry gauze pads, wet gauze pads, and adhesive external eye shields. RESULTS: When exposed to the 2940-nm Er:YAG and 10,600-nm CO2 lasers, dry gauze smoked on the first pulse and ignited on the second pulse, whereas no damage occurred to the wet gauze or adhesive eye shields after 8 and 4 pulses, respectively. No damage to any material or the underlying surface was seen after 30 pulses of the 532-nm KTP laser. After 2 pulses of the 1064-nm Nd:YAG laser, the adhesive eye shields sparked; dry gauze smoked after 1 pulse, but no damage to the underlying surface occurred after 30 pulses. CONCLUSIONS: The results of our study highlight the inherent flammability of gauze when exposed to lasers commonly used to address aesthetic facial concerns. Although moistened gauze conveyed more protection than dry gauze, these results do not guarantee patient ocular safety. Therefore, we do not recommend the use of any gauze under protective eyewear.

Bipolar Fractional Radiofrequency Treatment of Suprapatellar Skin Assessment Using Noninvasive Devices and Microbiopsy.

BACKGROUND: Noninvasive treatments for skin tightening are gaining popularity. However, no studies have assessed bipolar fractional radiofrequency treatment on suprapatellar skin. OBJECTIVES: The purpose of this study was to evaluate the efficacy of bipolar fractional radiofrequency treatment on suprapatellar skin. METHODS: Twenty patients received 1 bilateral suprapatellar bipolar fractional radiofrequency treatment. They returned 7 days, 3 weeks, 3 months, and 6 months posttreatment. Noninvasive measurements were obtained at each visit, including high-resolution ultrasonography, optical coherence tomography, transepidermal water loss and skin elasticity. Microbiopsies were collected in the treatment area for histologic and gene expression analyses. Three clinicians completed photographic evaluations comparing texture and laxity at baseline vs 6 months posttreatment. RESULTS: Fifteen subjects completed all 6 visits. Both transepidermal water loss and dermal-epidermal junction roughness were increased at 3 weeks and 3 months posttreatment. Both attenuation coefficient and stiffness were increased significantly at 3 and 6 months posttreatment. Blood flow 0.5 mm below the surface and expression of epidermal hyaluronic acid and inflammatory genes IL-1b and IL-6 were significantly higher at 7 days posttreatment compared with pretreatment and 3 months posttreatment. There were no statistically significant changes in collagen- or elastin-related genes and proteins at 7 days or 3 months posttreatment. An improvement in texture and laxity was observed at 6 months posttreatment in 17.7% and 24.4% of photographs, respectively. CONCLUSIONS: Radiofrequency treatment by microneedling of suprapatellar skin shows limited effects in decreasing skin laxity and improving skin appearance. At a molecular level, the treatment resulted in lower elastin and hyaluronic acid levels and increased dermal-epidermal junction roughness based on histology and optical coherence tomography imaging.

Holmium:YAG laser bronchoscopy ablation of benign and malignant airway obstructions: an 8-year experience.

Patients suffering from severe tracheobronchial obstruction are vulnerable to dyspnea, respiratory failure, obstructive pneumonia, and death. Treatment with a holmium:YAG laser, an alternative to the neodymium:YAG laser, may provide symptomatic relief. This is the largest case series to date describing the application of the holmium:YAG laser via bronchoscopy for benign and malignant obstructive disease. The data were retrospectively collected from 99 patients, with either benign or malignant tracheobronchial obstruction, who underwent 261 interventional bronchoscopy procedures in the operating room with laser ablation between January 2004 and November 2011. Categorical variables were analyzed with the chi-square and Fisher's exact tests as appropriate in contingency tables, whereas Student's t-test was performed for comparison of continuous variables. Patient follow-up was concluded on September 15, 2013. The holmium:YAG laser was used in 261 procedures performed on 99 patients with either benign or malignant disease. Symptomatic improvement was demonstrated in 90 % of all benign etiology cases and 77 % of all malignant etiology cases. Within the benign and malignant subgroups, improvement was dependent on anatomical location rather than etiology of the lesion. Complications occurred in 2.3 % of the procedures, with mortality in less than 1 % of procedures. Results confirm the usefulness and safety of the holmium:YAG laser in the treatment of patients with severe benign and malignant obstructive tracheobronchial obstructions. The holmium:YAG laser is an appealing alternative to the neodymium:YAG laser.

Five parameters you must understand to master control of your laser/light-based devices.

In this article, the authors review basic fundamental principles of light characteristics and their interaction with the target tissue. It is imperative for the practitioner to understand these concepts to deliver appropriate, efficacious, and safe phototherapeutic treatment for their patients. Once a diagnosis is made and a laser is chosen as a treatment tool, a basic knowledge and understanding of the physics and properties of light/tissue interaction is essential to allow practitioners to provide their patients with optimal results.

In vivo histopathologic comparison of the acute injury following treatment with five fractional ablative laser devices.

BACKGROUND: Both erbium (Er:YAG) and carbon dioxide (CO(2)) devices are commonly-used, efficient laser systems for aggressive skin resurfacing procedures. The devices each have different adjustable parameters (density, spot size, number of pulses, pattern, etc) and utilize variable energy capabilities to tailor individual treatments depending on the skin pathology and goals of treatment. Overall, the consensus has been that multiple-pass erbium treatments needed for efficacious wrinkle reduction had similar downtime and comorbidity to the traditional CO(2) treatments. Unfortunately, there were limited data comparing the histological differences and changes throughout the wound-healing process over time between the two treatment methods. OBJECTIVES: The authors compare the difference in injury following treatment with five novel fractional ablative laser systems in vivo. Differences in damage pattern, treatment depth, and degree of surrounding cellular injury following treatment with each device at common clinical settings are evaluated in a side-by-side histopathologic comparison. METHODS: Prior to planned excisional surgery, the panni of 20 abdominoplasty patients were treated with five novel ablative fractional carbon dioxide or Er:YAG laser systems at various clinical parameters, in accordance with the manufacturers' treatment guidelines. After tissue removal two to four hours later, the skin was biopsied and processed for histopathologic evaluation. Specimens were stained with hematoxylin and eosin, along with a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay, to highlight the degree of irreversible cellular injury. RESULTS: The acute damage profile differed between the fractional Er:YAG and CO(2) devices with respect to depth of penetration and extension of coagulation surrounding the microcolumns. The damage pattern was dependent on the parameters set with each device (eg, fluence, pulses, density, pulse width). The TUNEL-stained sections demonstrated more collateral cellular injury surrounding the ablated columns with the CO(2) devices than with the Er:YAG systems. CONCLUSIONS: Following treatment with the fractional Er:YAG and CO(2) devices, deep tissue injury with various coagulative and ablative properties was observed, and it was confirmed that carbon dioxide and erbium devices result in different patterns of injury. As such, each may be better suited for different clinical situations. It is important for practitioners to understand the limitations of a specific device, as well as the tissue injury following a given treatment pattern or protocol, to appropriately tailor their treatment algorithm for a given patient. This extensive histopathologic evaluation of the acute characterization of injury across devices is helpful in clarifying the differences/similarities in laser-tissue interaction following treatment in an in vivo human model.

TUNEL assay to characterize acute histopathological injury following treatment with the active and deep FX fractional short-pulse CO2 devices.

BACKGROUND: This is a report of the histopathological evaluation of the acute damage profile in human skin following treatment with two novel short-pulsed fractional carbon dioxide resurfacing devices used independently and in combination in vivo. METHODS: The panni of eight abdominoplasty patients were treated with either the Active FX, the Deep FX (Lumenis Ltd., Yokneum, Israel), or a combination of the two (Total FX) prior to the start of the excisional surgical procedure. Multiple combinations of energies, pulse widths, and densities were evaluated for each device. After surgical removal (two to five hours), each pannus was immediately biopsied and samples were processed for histopathological evaluation. RESULTS: The Active FX system resulted in extensive epidermal injury with wide shallow ablation craters that, at higher fluences, extended through the basement membrane of the epidermis into the papillary dermis. The Deep FX fractional treatment caused deep microcolumns of ablation penetrating up to 3 to 4 mm from the epidermal surface into the deep reticular dermis with a variable rim of coagulated collagen surrounding each ablation column. CONCLUSIONS: The in vivo histopathological evaluation of these devices furthers our understanding of the fundamental laser/tissue interaction following treatment with each device independently and in combination.

Treating Hypertrophic Burn Scar With 2940-nm Er:YAG Laser Fractional Ablation Improves Scar Characteristics as Measured by Noninvasive Technology.

Their group previously demonstrated high-patient satisfaction for the treatment of hypertrophic burn scar (HBS) with the erbium: yttrium aluminum garnet (Er:YAG) laser, but this and other literature supporting the practice suffer from a common weakness of a reliance on subjective assessments by patients or providers. Herein, they sought to prospectively study the effects of Er:YAG fractional ablation on HBS using noninvasive, objective technologies to measure outcomes. Patients with HBS had identical regions of scar designated for treatment by the Er:YAG laser (TREAT) or to be left untreated (CONTROL). They prospectively collected scar measurements of TREAT and CONTROL regions preoperatively, 3 weeks, and 3 months after Er:YAG treatment. Scar measurements included viscoelastometry, transepidermal water loss, optical coherent tomography, and high-frequency ultrasound. Outcomes were measured for the aggregate difference between the TREAT group vs the CONTROL group, as well as within each group in isolation. Seventeen patients were seen preoperatively, followed by n = 15 at 3 weeks and n = 11 at 3 months. A mixed-model repeated measures analysis showed no significant effect of fractional ablation when comparing the overall TREAT group measurements with those of the CONTROL group. However, when considered as within-group measurements, TREAT scars showed significant improvement in viscoelastic deformity (P = .03), elastic deformity (P = .004), skin roughness (P = .05), and wrinkle depth (P = .04) after fractional ablation, whereas CONTROL scars showed no such within-group changes. HBS treated by the Er:YAG laser showed objective improvements, whereas no such changes were seen within the untreated scars over the same time frame.

Effects of common laser treatments on hyaluronic acid fillers in a porcine model.

BACKGROUND: Injectable hyaluronic acid fillers (HAFs) and laser/light procedures have become increasingly popular for noninvasive facial rejuvenation in many cosmetic practices. However, the effect of laser/light treatments on HAFs is unknown. OBJECTIVE: Our objective was to examine the effect of laser/light treatments on HAFs in a porcine model. METHODS: The abdomens of 6 Yorkshire pigs were injected with 3 different HAFs: Restylane (Medicis, Scottsdale, AZ), Perlane (Medicis), and Juvéderm (Allergan, Santa Barbara, CA). Two weeks after injection, the injection sites were treated with 1 of 7 common laser/light ablative or nonablative devices. Following laser treatment, 8-mm punch biopsies were collected from the treated tissue and fixed for histopathologic evaluation. Sections were stained with hematoxylin-eosin and alcian blue stains for identification of the preinjected HAF. RESULTS: The filler was identified in different areas of the dermis in different sections. The Sciton intense pulsed 560 nm filter (Sciton, Palo Alto, CA), the Sciton Nd: YAG, Lux1540 (Palomar Medical Technologies, Burlington, MA), or ActiveFX (Lumenis, Yokneum, Israel) treatments showed no sign of interaction with superficial or deep dermal filler. No evidence of morphologic changes to the filler or the surrounding tissues was observed. Obvious interaction between the HAFs and the laser injury was demonstrated in sections treated with the deep ablative systems fractional erbium 2940 (Profractional; Sciton) and DeepFX CO(2), (Lumenis). However, no uncharacteristic tissue injury or morphologic change in the filler was appreciated in any of the preinjected specimens. CONCLUSIONS: Injected HAFs were unaffected by the nonablative laser/light and superficial ablative treatments. The more aggressive deeper laser treatments demonstrated laser/filler interaction and may have a clinical effect on the longevity of the filler and/or efficacy of laser treatments. Novel ablative fractional lasers have the capability of deep dermal penetration, and this should be taken into consideration when planning to use them in combination with soft tissue fillers for noninvasive facial rejuvenation.

Patient satisfaction after fractional ablation of burn scar with 2940nm wavelength Erbium-Yag laser.

OBJECTIVE: Fractional laser therapy is a new treatment with potential benefit in the treatment of burn scars. We sought to determine patient satisfaction after burn scar treatment with the Erbium-Yag laser. METHODS: We performed a telephone survey of all patients who underwent fractional resurfacing of burn scars with the Erbium-Yag 2940 wavelength laser at Parkland Hospital from 01/01/2016 to 05/01/2017. Subjects were asked to rate their satisfaction with their scars' after treatment characteristics on a scale from 1 (completely unsatisfied) to 10 (completely satisfied). Subjects were also asked to assess their treatment response using the UNC 4P Scar Scale before and after treatment. RESULTS: Sixty-four patients underwent 156 treatments. A survey response rate of 77% (49/64) was seen (age: 36.8+21 years; surface area treated=435+326cm2; 35% of burn scars were >2 years old; mean scar age of 1.02+0.4 years). Overall, 46/49 (94%) of patients reported some degree of scar improvement after treatment. Patient satisfaction scores were 8.3+2.3. Number of laser treatments included: 1 (31%), 2 (33%), 3 (18%), 4(10%), >5 (8%). Treatment depth, scar age, and number of laser procedures were not significant predictors of satisfaction or UNC 4P Scar scores. The paired t-test showed a significant reduction on each of the UNC 4P Scar scale items (pain, pruritus, pliability, paresthesia). One subject reported that she felt that the laser treatment made her scar worse (2%). CONCLUSION: Burn patients treated with the Erbium-Yag laser are highly satisfied with changes in their burn scars.

Impact of a Laser Service Line for Burn Scar on a Dedicated Burn OR's Flow and Productivity.

Our group began performing erbium-YAG 2940 wavelength fractional resurfacing of burn scar in our burn center's dedicated burn operating room (OR) in January 2016. The impact of these procedures on the performance of a mature, dedicated burn OR is unknown. All burn OR cases performed between January 1, 2015 and December 31, 2015 served as a pre-laser (PRE-LSR) historical control. A postintervention cohort of laser-only cases (LSR) performed between January 1, 2016 and August 17, 2016 was then identified. PRE-LSR and LSR cases were retrospectively reviewed for OR component times, and work relative value units (wRVU) billed. A total of 628 burn OR cases were done in 2015 (PRE-LSR), while 488 burn OR cases were done between January 1 and August 17, 2016. Of these 488, 59 cases were LSR (12.1%). Calculated on a monthly basis, significantly more cases were done per day in the LSR era (2.2 ± 0.4 cases/d) than PRE-LSR (1.6 ± 2.0 cases/d; P < .0001). The LSR group was significantly shorter than the PRE-LSR group for all OR component times (induction, prep, and procedure all P < .0001; transport out, P = .01; room turnover, P = .004). Aggregate OR component time was 79.2 ± 33.4 minutes for LSR and 157.5 ± 65.0 minutes for PRE-LSR (P < .0001). LSR yielded 6.9 ± 3.2 wRVU/h, while PRE-LSR generated 12.2 ± 8.9 wRVU/h (P < .0001). Despite significantly shorter OR component times and more cases being done per day, laser treatment of burn scar using a single 17108 Current Procedural Terminology code cuts wRVUs generated per hour in a mature burn OR roughly in half.

Problems and complications of full-face carbon dioxide laser resurfacing for pathological lesions of the skin.

OBJECTIVE: Facial resurfacing with a CO2 laser has been used for treatment of pathologic lesions and for cosmetic purposes. Postoperative complications and problems after laser resurfacing include infections, acneiform lesions, and pigment changes. This retrospective study describes the most common problems and complications in 105 patients and assesses postoperative pain in 38 patients. STUDY DESIGN: All patients received CO2 laser resurfacing for treatment of malignant/premalignant lesions and had postoperative follow-up to assess problems and complications. Some had follow-up to assess postoperative pain. All patients had Fitzpatrick I-III skin types and underwent the same perioperative care regimen. RESULTS: There were 11 problems and 2 complications. Problems included infection, acneiform lesion/milia, and uncontrolled postoperative pain. Complications included hyperpigmentation. Among the postoperative pain group, 53% reported no pain and the rest had mild or moderate pain. CONCLUSION: Complications are rare. Infection and acneiform lesions/milia were the most common problems, as previously reported. Most patients do not experience postoperative pain.

TUNEL assay for histopathologic evaluation of irreversible chromosomal damage following nonablative fractional photothermolysis.

BACKGROUND: Fractional photothermolysis is extremely popular in skin rejuvenation and remodeling procedures. However, the extent of thermal cellular injury beyond the borders of the coagulated microcolumns produced with fractional phototherapy is undefined. METHODS: Six abdominoplasty patients were pretreated with the Lux1540 Fractional Erbium device (Palomar, Inc., Burlington, Mass.) at various clinical laser settings. After tissue excision, the panni were immediately biopsied. Biopsy specimens were fixed in formalin, embedded in paraffin, sectioned, and evaluated with the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) procedure for cellular necrosis/apoptosis. Tissue was sectioned horizontally and longitudinally to help define the depth and distribution of the microcolumns of injury in a three-dimensional plane. RESULTS: The extent of cellular necrosis/apoptosis at variable depths within the epidermis and dermis was demonstrated successfully with the TUNEL technique. After the Lux1540 treatment, TUNEL-positive nuclei were identified in a vertically oriented fashion that extended from the epidermis into the papillary and reticular dermis, highlighting the areas of injury. The TUNEL-positive nuclei defined lesions that were approximately 175 to 225 microm in diameter and penetrated to variable depths (200 to 900 microm), depending on the fluence used for treatment (18 to 100 mJ). CONCLUSIONS: TUNEL immunofluorescent labeling provided an accurate assessment of cellular damage within and surrounding the microthermal zones of coagulated collagen with respect to column depth and width. Because of its specificity, the TUNEL assay can be a useful adjunct to other histologic stains used to characterize cellular damage and matrix denaturation in skin treated with any fractional ablative or nonablative laser device.

Evaluation of flashlamp-pumped pulsed-dye laser (585 nm) in nonsurgical delay of dorsal rat cutaneous flaps.

BACKGROUND: This study evaluated the efficiency of a flashlamp-pumped pulsed-dye laser operating at 585 nm in the delay of a caudally based, 10 x 3-cm dorsal rat skin flap. Two different laser treatment patterns (only longitudinal borders and the entire surface of the proposed flap) for two different fluences (6 J/cm and 8 J/cm) were compared with an acute untreated control flap as well as two surgical delay methods (incision of longitudinal borders and incision of longitudinal borders plus flap undermining). METHODS: Twelve male Sprague-Dawley rats were used in each of seven groups. Two additional rats were used for histologic evaluation and two rats were used for in vivo real-time video monitoring studies. Two weeks after delay procedures, the flaps were raised and sutured on the primarily closed flap donor area. After 5 days, the length of flap survival was measured. The effects of the laser on the cutaneous vasculature and perfusion were assessed by intravenous fluorescein injection, histologic analysis, microangiography, and in vivo real-time video monitoring. RESULTS: No statistically significant improvement in flap survival was observed in any of the laser treatment groups. CONCLUSIONS: The overall findings indicate that the flashlamp-pumped pulsed-dye laser operating at 585 nm did not penetrate deep into skin and coagulate the subdermal plexus with tested laser settings and did not induce the delay phenomenon.

Nonsurgical delay of dorsal rat cutaneous flap using a long-pulsed 1064-nm Nd:YAG laser with a contact cooling device.

BACKGROUND: This study evaluated the efficiency of a long-pulsed neodymium:yttrium-aluminum-garnet laser, operating at 1064 nm and equipped with a contact cooling device, in the delay of a caudally based dorsal rat skin flap (10 x 3 cm). This laser has deeper tissue penetration and has not been used for this purpose before. METHODS: Twelve male Sprague-Dawley rats were used in each of six groups. The delay effects of three different laser treatment patterns (only longitudinal borders, cephalic and longitudinal borders, and entire surface of the 10 x 3-cm flap) were compared with an acute untreated control flap as well as two surgical delay methods (incision of longitudinal borders and incision of longitudinal borders plus flap undermining). The laser effects on the cutaneous vasculature and perfusion were assessed by intravenous fluorescein injection, histologic study, microangiography, and in vivo real-time video monitoring. RESULTS: Selective thermocoagulation of subdermal vessels was achieved using a 6-mm spot, 140-J/cm fluence, and 40-msec pulse width. In the cephalic and longitudinal borders laser-treated group, a delay effect was achieved. The maximum delay effect was achieved by the surgical delay group that used the method of incision of the longitudinal borders plus flap undermining. Laser treatment of only the longitudinal borders did not improve flap survival, whereas treatment of the entire flap surface significantly reduced flap survival. CONCLUSION: Nonsurgical delay of a dorsal rat cutaneous flap is possible by selective occlusion of the subdermal plexus at the longitudinal and cephalic borders of the planned flap using a long-pulsed 1064-nm neodymium:yttrium-aluminum-garnet laser equipped with a contact cooling device.