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CO2 Laser (co2 + laser)
Kinds of CO2 Laser Terms modified by CO2 Laser Selected AbstractsImprovement of Dermatochalasis and Periorbital Rhytides With a High-Energy Pulsed CO2 Laser: A Retrospective StudyDERMATOLOGIC SURGERY, Issue 4 2004Tina S. Alster MD Background. Upper eyelid dermatochalasis is typically treated with excisional blepharoplasty. The role of the CO2 laser previously had been confined to that of a vaporizing, incisional, or hemostatic tool. Over the past several years, however, ablative CO2 laser skin resurfacing has been popularized as an adjunctive treatment to blepharoplasty to minimize periorbital rhytides through its vaporizing as well as skin-tightening action. Objective. To evaluate the safety and efficacy of a high-energy pulsed CO2 laser as a stand-alone treatment for dermatochalasis and periorbital rhytides. Methods. Sixty-seven patients (skin phototypes I,IV) with mild-to-severe upper eyelid dermatochalasis and periorbital rhytides received periocular CO2 laser skin treatment. Global assessment scores of dermatochalasis and rhytides were determined by a side-by-side comparison of periocular photographs preoperatively and 1, 3, and 6 months postoperatively. In addition, caliper measurements of upper eyelids before and 1, 3, and 6 months after treatment were obtained. Results. Both dermatochalasis and periorbital rhytides were significantly improved after periocular CO2 laser skin resurfacing. Patients with more severe dermatochalasis and rhytides showed greater improvement after CO2 laser treatment than did those with mild or moderate involvement. Side effects were limited to erythema and transient hyperpigmentation. No scarring, hypopigmentation, or ectropion were observed. Conclusions. Periocular skin resurfacing with a CO2 laser can safely and effectively improve upper eyelid dermatochalasis and periorbital rhytides. [source] Combined Ultrapulse CO2 Laser and Q-Switched Alexandrite Laser Compared with Q-Switched Alexandrite Laser Alone for Refractory Melasma: Split-Face DesignDERMATOLOGIC SURGERY, Issue 1 2003Suhattaya Angsuwarangsee MD Background. Melasma is common and can cause major psychological impact. To date, the mainstay of treatment, including various hypopigmenting agents and chemical peels, is ineffective and can cause adverse effects. Laser is a new approach and is yet to be explored for its efficacy and safety. Objective. To compare combined Ultrapulse CO2 laser and Q-switched alexandrite laser (QSAL) with QSAL alone in the treatment of refractory melasma. Methods. Six Thai females were treated with combined Ultrapulse CO2 laser and QSAL on one side of the face and QSAL alone on the other side. The outcome was evaluated periodically for up to 6 months using the modified Melasma Area and Severity Index score and the modified Melasma Area and Melanin Index score. Results. The side with combination treatment had a statistically significant reduction of both scores. On the QSAL side, the score reduction was not significant. Two cases developed severe postinflammatory hyperpigmentation and were effectively treated with bleaching agents. Transient hypopigmentation and contact dermatitis were observed with the combination treatment side. Conclusions. Combined Ultrapulse CO2 laser and QSAL showed a better result than QSAL alone but was associated with more frequent adverse effects. Long-term follow-up and a larger number of cases are required to determine its efficacy and safety for refractory melasma. [source] Recurrent Ingrown Big Toenails Are Efficiently Treated by CO2 LaserDERMATOLOGIC SURGERY, Issue 6 2002Francis Serour MD background. Surgery for onychocryptosis has a high rate of recurrence. objective. To evaluate CO2 laser partial matricectomy for recurrent onychocryptosis. methods. One hundred ninety-six consecutive patients (predominantly teenagers) previously unsuccessfully treated by surgery underwent CO2 laser for recurrent onychocryptosis. After a digital nerve block and a simple partial nail plate avulsion, the laser was used (5 W, defocused 2 mm beam in continuous mode) to vaporize the matrix, the lateral horn, and the lateral nail groove, including local granulation tissue if present. Follow-up was at least 12 months. results. Three hundred forty-four matricectomies were performed. Disease was mostly at stage II and III, with severe local infection in 24 cases (12.2%). All wounds healed in 21.9 ± 3.2 days, with no postoperative local infection or prolonged exudative drainage. Onychocryptosis reoccurred in 5 of 344 treated margins (1.45%, average 15 months), all after primary bilateral matricectomy. Spicules in the lateral nail groove occurred in 14 of 344 treated margins (4%, average 5.9 months), mostly after primary bilateral matricectomy (7 cases) and in infected margins (8 cases). One patient developed a neuroma in the lateral nail groove. conclusion. CO2 laser is effective for the treatment of recurrent onychocryptosis. Bilateral matricectomy and local infection seem to be the predisposing factors for recurrence and postoperative spicule growth. [source] Concomitant Use of a High-Energy Pulsed CO2 Laser and a Long-Pulsed (810 nm) Diode Laser for Squamous Cell Carcinoma in SituDERMATOLOGIC SURGERY, Issue 1 2002Darrell J. Fader MD First page of article [source] Comparison of Electrodessication with CO2 Laser for the Treatment of Actinic CheilitisDERMATOLOGIC SURGERY, Issue 4 2000Richard A. Laws MD Background. Actinic cheilitis is a common premalignant condition that is most often treated with destructive therapy. The most effective technique is usually considered to be CO2 laser resurfacing. Little has been written on the use of electrodessication for this condition. Objective. We designed a study to compare these two treatment modalities for the treatment of biopsy-confirmed actinic cheilitis. Methods. A random half of the lower lip was treated with electrodessication. The contralateral half was then treated with CO2 laser. Healing time, subjective pain during healing, and clinical outcome at 3 months was compared. Results. The side treated with electrodessication took significantly longer to heal than the side treated with the CO2 laser (23 versus 14 days, P < .001). There was no difference in subjective pain or clinical appearance at 3 months. Conclusion. Although the healing time is longer with electrodessication, this modality represents an inexpensive practical ablative treatment method for actinic cheilitis. [source] CO2 Laser , Workhorse for Industrial ManufacturingLASER TECHNIK JOURNAL, Issue 3 2009Flexible, reliable, well proven tool for a large variety of laser processing systems For more than 30 years lasers are used for industrial production with high success. Modern efficient production would not be imaginable without lasers and laser processes. Since the beginning days CO2 lasers were dominating the market of continuous cutting and welding applications (referred here as "Macro" applications) because of their high power and electrical efficiency, reliability and cost efficiency. [source] Microdissection or Microspot CO2 Laser for Limited Vocal Fold Benign Lesions: A Prospective Randomized Trial,THE LARYNGOSCOPE, Issue S92 2000Michael S. Benninger MD CO2 lasers have become an important technological advance and an integral tool for the laryngeal surgeon since the 1960s. Surgeons have used lasers for a variety of benign and malignant lesions in the larynx with good success. With better understanding of the microarchitecture of the vocal folds and the recognition of heat distribution into surrounding tissues that occurs with the use of standard CO2 lasers, questions and concerns have been raised regarding the use of the CO2 laser for benign lesions of the vocal folds. With the advent of the microspot CO2 laser with a spot size of less than 250 ,m, the potential heat distribution to the deeper layers of the lamina propria has been reduced. The microspot CO2 laser has been suggested to be an appropriate tool for the excision of superficial benign lesions of the vocal fold and may be considered as an appropriate treatment alternative to microdissection. Only a limited number of studies have compared the efficacy of microdissection versus microspot CO2 laser surgery in the larynx, and no prospective, randomized trials have been performed. Objective This study was designed to compare microspot CO2 laser excision and microdissection for superficial benign lesions confined to the free margin of the vocal fold. Study Design: A randomized, prospective trial comparing microspot CO2 laser excision and microdissection in the removal of nodules, polyps, and mucous retention cysts of the vocal fold. Methods Acoustic and aerodynamic measures and videostroboscopic and perceptual audio recordings evaluated by a panel of blinded viewers and listeners were studied preoperatively and 2 to 3 weeks and 5 to 12 weeks postoperatively. Surgical and recovery times were compared between the two groups. Results Thirty-seven patients met selection criteria and were enrolled, 21 in the microdissection group and 16 in the laser excision group. Significant improvements in videostroboscopic parameters were found over time in both groups. Significant improvements were noted for perceptual analysis over time for the laser excision group with nonsignificant improvements over time for the microdissection group. There was no difference in any measure between laser excision and microdissection at the two postoperative visits. There was no difference in surgical or recovery time between laser excision and microdissection. Acoustic and aerodynamic parameters were noncontributory in evaluating outcomes of treatment, since most values were normal before surgery. Conclusion No differences in clinical outcomes are identified when comparing microdissection with laser excision of nodules, polyps, and mucous retention cysts of the vocal folds. [source] The Treatment of Melasma with Fractional Photothermolysis: A Pilot StudyDERMATOLOGIC SURGERY, Issue 12 2005Cameron K. Rokhsar MD Background. Melasma is a common pigmentary disorder that remains resistant to available therapies. Facial resurfacing with the pulsed CO2 laser has been reported successful but requires significant downtime, and there is a risk of adverse sequelae. Objective. To determine if melasma will respond to a new treatment paradigm, fractional resurfacing. Methods. Ten female patients (Fitzpatrick skin types III,V) who were unresponsive to previous treatment were treated at 1- to 2-week intervals with the Fraxel laser (Reliant Technologies, Palo Alto, CA, USA). Wavelengths of 1,535 and 1,550 nm were both used, and 6 to 12 mJ per microthermal zone with 2,000 to 3,500 mtz/cm2 were the treatment parameters. Four to six treatment sessions were performed. Responses were evaluated according to the percentage of lightening of original pigmentation. Two physicians evaluated the photographs, and each patient evaluated her own response. Results. The physician evaluation was that 60% of patients achieved 75 to 100% clearing and 30% had less than 25% improvement. The patients' evaluations agreed, except for one patient, who graded herself as 50 to 75% improved as opposed to the physician grading of over 75%. There was one patient with postinflammatory hyperpigmentation and no patient with hypopigmentation. No downtime was necessary for wound healing. Conclusions. Fractional resurfacing affords a new treatment algorithm for the treatment of melasma that combines decreased risk and downtime with significant efficacy. This treatment modality deserves further exploration to maximize benefits. RELIANT technologies LOANED THE FRAXEL LASER FOR THE STUDY. RICHARD E. FITZPATRICK, MD, IS A PAID CONSULTANT FOR RELIANT AND A STOCKHOLDER. [source] Clear Cell Acanthoma Successfully Treated with a Carbon Dioxide LaserDERMATOLOGIC SURGERY, Issue 10 2005Ching-Chi Chi MD Background. The treatment of choice for clear cell acanthoma (CCA) is excision. Resolution after cryotherapy has also been reported but requires three to four courses of treatment. Objective. To demonstrate three CCA lesions in two patients successfully treated with a carbon dioxide (CO2) laser. Methods. Under local anesthesia, these lesions were vaporized by using a CO2 laser in the Silktouch mode with a spot size of 5 mm and a fluence of 20 J/cm2. Two to six passes, as needed, were delivered until the tumor was completely removed. Results. Pain was minimal or nonexistent during and after the operation. No postoperative edema was noted. The wounds healed satisfactorily without scarring. No sign of recurrence was found following operation. Conclusion. The CO2 laser has the advantages of requiring only one course, precise tumor removal, a relatively bloodless surgical field, a short operation time, and less or no postoperative pain and edema. Postoperative wound care is convenient and easy with hydrocolloid and alginate dressings. The patient's quality of life is less adversely affected. The CO2 laser may be appropriate for multiple CCAs, giant CCA, CCA overlying or near joints, CCA refractory to cryotherapy, patients on anticoagulants, and those who cannot tolerate pain from cryotherapy, especially children and the elderly. [source] Improvement of Dermatochalasis and Periorbital Rhytides With a High-Energy Pulsed CO2 Laser: A Retrospective StudyDERMATOLOGIC SURGERY, Issue 4 2004Tina S. Alster MD Background. Upper eyelid dermatochalasis is typically treated with excisional blepharoplasty. The role of the CO2 laser previously had been confined to that of a vaporizing, incisional, or hemostatic tool. Over the past several years, however, ablative CO2 laser skin resurfacing has been popularized as an adjunctive treatment to blepharoplasty to minimize periorbital rhytides through its vaporizing as well as skin-tightening action. Objective. To evaluate the safety and efficacy of a high-energy pulsed CO2 laser as a stand-alone treatment for dermatochalasis and periorbital rhytides. Methods. Sixty-seven patients (skin phototypes I,IV) with mild-to-severe upper eyelid dermatochalasis and periorbital rhytides received periocular CO2 laser skin treatment. Global assessment scores of dermatochalasis and rhytides were determined by a side-by-side comparison of periocular photographs preoperatively and 1, 3, and 6 months postoperatively. In addition, caliper measurements of upper eyelids before and 1, 3, and 6 months after treatment were obtained. Results. Both dermatochalasis and periorbital rhytides were significantly improved after periocular CO2 laser skin resurfacing. Patients with more severe dermatochalasis and rhytides showed greater improvement after CO2 laser treatment than did those with mild or moderate involvement. Side effects were limited to erythema and transient hyperpigmentation. No scarring, hypopigmentation, or ectropion were observed. Conclusions. Periocular skin resurfacing with a CO2 laser can safely and effectively improve upper eyelid dermatochalasis and periorbital rhytides. [source] Combined Ultrapulse CO2 Laser and Q-Switched Alexandrite Laser Compared with Q-Switched Alexandrite Laser Alone for Refractory Melasma: Split-Face DesignDERMATOLOGIC SURGERY, Issue 1 2003Suhattaya Angsuwarangsee MD Background. Melasma is common and can cause major psychological impact. To date, the mainstay of treatment, including various hypopigmenting agents and chemical peels, is ineffective and can cause adverse effects. Laser is a new approach and is yet to be explored for its efficacy and safety. Objective. To compare combined Ultrapulse CO2 laser and Q-switched alexandrite laser (QSAL) with QSAL alone in the treatment of refractory melasma. Methods. Six Thai females were treated with combined Ultrapulse CO2 laser and QSAL on one side of the face and QSAL alone on the other side. The outcome was evaluated periodically for up to 6 months using the modified Melasma Area and Severity Index score and the modified Melasma Area and Melanin Index score. Results. The side with combination treatment had a statistically significant reduction of both scores. On the QSAL side, the score reduction was not significant. Two cases developed severe postinflammatory hyperpigmentation and were effectively treated with bleaching agents. Transient hypopigmentation and contact dermatitis were observed with the combination treatment side. Conclusions. Combined Ultrapulse CO2 laser and QSAL showed a better result than QSAL alone but was associated with more frequent adverse effects. Long-term follow-up and a larger number of cases are required to determine its efficacy and safety for refractory melasma. [source] CO2 Laser Treatment of Epidermal Nevi: Long-Term SuccessDERMATOLOGIC SURGERY, Issue 7 2002Sarah Boyce MD background. Epidermal nevi have been notoriously difficult to treat due to their large size and often conspicuous location. Variable results have been obtained with different laser treatments, and scarring and/or incomplete removal is typical after excisional or other destructive modalities. objective. To outline the successful use of a short-pulsed CO2 laser in the long-term eradication of epidermal nevi in three patients. methods. Three females (ages 15,19) presented with extensive grouped verrucous papules and plaques on the face, trunk, and extremities. A pulsed CO2 laser was used to vaporize the lesions using a 500 mJ pulse energy, 3 mm spotsize, and 7 watts of power. results. All lesions healed without incident. No lesional recurrence was observed 10 to 13 months after treatment except in one small area on the ankle in one patient. conclusions. Carbon dioxide laser vaporization of epidermal nevi provides good clinical effect and offers unique advantages for the treatment of these lesions, including effective intraoperative hemostasis with excellent lesional visualization. It is also possible to treat widespread areas in one laser treatment session. While the results of this series clearly show the benefit of CO2 laser treatment, epidermal nevi may not always respond so favorably, due in part to the variability in their depths of involvement. [source] The Laser-Assisted Neck Lift: Modifications in Technique and Postoperative Care to Improve ResultsDERMATOLOGIC SURGERY, Issue 6 2002F. Richard Noodleman MD background. Conventional submental tumescent liposuction has proved disappointing for some patients with anterior neck laxity, ptotic platysma muscles, and increased subplatysmal fat. Many of these patients are facelift candidates but are unwilling to undergo this extensive procedure. We describe our hybrid approach, which offers consistently improved results and enhanced patient satisfaction. objective. To establish a sharper cervicomental angle by more completely removing subplatysmal fat. We also wished to achieve more consistent, smoother results, minimizing ripples, folds, and hematomas with a novel postoperative dressing system. methods. Extensive tumescent liposuction of the lower face, jowls, and anterior neck was performed. Following this, subplatysmal fat was removed by dissection, the platysma muscle was imbricated, and the CO2 laser utilized in a defocused, low-power mode to partially treat the dermal undersurface and underlying muscle. Our postoperative dressing included a 10 cm mineral oil polymer gel disc in the submental location, covered by tape, silicone foam, and a lower face and neck garment to provide both support and even compression over the entire neck for at least the first 24 hours. results. Results proved uniformly satisfying for most patients, even those in their senior years. Benefits included an improved cervicomental angle, a decrease in jowling, and a marked reduction in the laxity and wrinkling of the neck skin and horizontal neck creases. Problems related to postoperative rippling or folding of the redraped skin and hematoma formation were minimized. conclusion. Laser neck tightening combined with tumescent liposuction and an advanced postoperative dressing for superior support and uniform compression has resulted in consistently excellent outcomes with improved patient satisfaction. [source] Recurrent Ingrown Big Toenails Are Efficiently Treated by CO2 LaserDERMATOLOGIC SURGERY, Issue 6 2002Francis Serour MD background. Surgery for onychocryptosis has a high rate of recurrence. objective. To evaluate CO2 laser partial matricectomy for recurrent onychocryptosis. methods. One hundred ninety-six consecutive patients (predominantly teenagers) previously unsuccessfully treated by surgery underwent CO2 laser for recurrent onychocryptosis. After a digital nerve block and a simple partial nail plate avulsion, the laser was used (5 W, defocused 2 mm beam in continuous mode) to vaporize the matrix, the lateral horn, and the lateral nail groove, including local granulation tissue if present. Follow-up was at least 12 months. results. Three hundred forty-four matricectomies were performed. Disease was mostly at stage II and III, with severe local infection in 24 cases (12.2%). All wounds healed in 21.9 ± 3.2 days, with no postoperative local infection or prolonged exudative drainage. Onychocryptosis reoccurred in 5 of 344 treated margins (1.45%, average 15 months), all after primary bilateral matricectomy. Spicules in the lateral nail groove occurred in 14 of 344 treated margins (4%, average 5.9 months), mostly after primary bilateral matricectomy (7 cases) and in infected margins (8 cases). One patient developed a neuroma in the lateral nail groove. conclusion. CO2 laser is effective for the treatment of recurrent onychocryptosis. Bilateral matricectomy and local infection seem to be the predisposing factors for recurrence and postoperative spicule growth. [source] Treatment of Recurrent Ingrown Great Toenail Associated with Granulation Tissue by Partial Nail Avulsion Followed by Matricectomy with Sharpulse Carbon Dioxide LaserDERMATOLOGIC SURGERY, Issue 5 2002Kuo-chia Yang MD background. The effectiveness of partial nail avulsion followed by matricectomy with carbon dioxide (CO2) laser for the treatment of ingrown great toenails remains unclear. objective. This study sought to determine the effectiveness of partial nail avulsion followed by matricectomy with sharpulse CO2 laser in the treatment of recurrent ingrown great toenails associated with granulation tissue. materials and methods. Fourteen patients with a total of 18 recurrent ingrown great toenails were randomly selected for participation in this study. Partial nail avulsions followed by matricectomy with sharpulse CO2 laser were performed on the involved nails. After at least 6 months, we evaluated the recurrence of ingrown toenails, regrowth of the nail spike, duration of post-treatment pain and post-treatment infection. results. Partial nail avulsion followed by matricectomy with sharpulse CO2 laser in the treatment of ingrown toenails resulted in a high cure rate, short postoperative pain duration and low risk of postoperative infection. conclusion. This method we advocate is convenient and effective for the treatment of recurrent ingrown great toenail associated with granulation tissue. [source] Port-Wine Stain Nodules in the Adult: Report of 20 Cases Treated by CO2 Laser VaporizationDERMATOLOGIC SURGERY, Issue 8 2001Jesús Del Pozo MD Background. Port-wine stain (PWS) is a congenital vascular malformation of the superficial dermal vessels. These vessels become progressively ectatic, with development of nodular and hypertrophic areas on the surface of the lesions. Objective. To determine the efficacy of CO2 laser vaporization in the treatment of nodules in PWS. Methods. Twenty adult patients with PWS who developed nodules and hypertrophy on the surface of the lesions were treated by CO2 laser vaporization. Only one pass was performed to each area of the lesions, using a continuous and defocused mode, with a power density of 10 W/cm2. When the treated lesion was very large, several sessions of treatment were necessary to vaporize its entire surface. Photographic controls were performed before and after treatment. Results. The nodules and hypertrophy were removed and the smooth surface of the lesions was reestablished. The color, usually violaceous, was transformed in a slight erythema. Conclusion. CO2 laser is a good method for treatment of nodules and hypertrophy in PWS. With adequate precautions, excellent cosmetic results can be obtained. Other more-specific laser systems may be successively used to treat the remaining erythema. [source] Laser-Assisted Hair Transplantation: Histologic Comparison Between CO2 and Ho:YAG LasersDERMATOLOGIC SURGERY, Issue 4 2001Eugene A. Chu MD Background. Various laser wavelengths and devices have been advocated for use in the creation of recipient channels during hair transplant surgery, including flash-scanned CO2, Ho:YAG (, = 2.12 ,m), and Er:YAG (, = 2.94 ,m). Objective. To determine the tissue injury caused by flash-scanned CO2 and pulsed Ho:YAG lasers during the creation of hair transplant recipient channels and to assess the efficacy of the Ho:YAG laser. Methods. Recipient channels were created in vivo in human scalp tissue using both lasers, and were excised and prepared for histologic examination. Optical micrometry of tissue sections was used to assess thermal injury. Results. The Ho:YAG laser created jagged, irregular-shaped channels with larger zones of thermal injury (superficial deepithelialization, thermal necrosis, and thermal damage). In contrast, the CO2 laser produced well-defined cylindrically shaped channels free of cellular debris with minimal epithelial disruption and significantly less lateral thermal injury. Conclusion. Given that the Ho:YAG produced larger regions of thermal injury and recipient channels that were unacceptable for graft, the CO2 laser remains the better choice for the creation of recipient channels during hair transplant surgery. However, ongoing research will be necessary to determine the optimal laser wavelength and/or devices for this procedure. [source] Suction Device for Epidermal Grafting in Vitiligo: Employing a Syringe and a Manometer to Provide an Adequate Negative PressureDERMATOLOGIC SURGERY, Issue 7 2000Han-uk Kim MD Background. Suction devices for epidermal grafting need a suction pump to provide a negative pressure. The authors have developed a suction device in which a syringe and a manometer are employed to provide a negative pressure. Objective. The purpose of this study was to evaluate the efficacy of our suction device in vitiligo patients. Methods. The suction device was used to obtain epidermal blisters from the donor site. A CO2 laser was employed to remove the depigmented epidermis. The blister roofs of the donor site were harvested and were placed onto the recipient area. Ten patients with stable vitiligo were treated by epidermal grafting. Results. Epidermal blisters were produced by suction in all patients. Also, all 10 patients regained repigmentation. Conclusion. Our suction blister device is simple and inexpensive to make, and it may become an alternative to the other suction devices. [source] Comparison of Electrodessication with CO2 Laser for the Treatment of Actinic CheilitisDERMATOLOGIC SURGERY, Issue 4 2000Richard A. Laws MD Background. Actinic cheilitis is a common premalignant condition that is most often treated with destructive therapy. The most effective technique is usually considered to be CO2 laser resurfacing. Little has been written on the use of electrodessication for this condition. Objective. We designed a study to compare these two treatment modalities for the treatment of biopsy-confirmed actinic cheilitis. Methods. A random half of the lower lip was treated with electrodessication. The contralateral half was then treated with CO2 laser. Healing time, subjective pain during healing, and clinical outcome at 3 months was compared. Results. The side treated with electrodessication took significantly longer to heal than the side treated with the CO2 laser (23 versus 14 days, P < .001). There was no difference in subjective pain or clinical appearance at 3 months. Conclusion. Although the healing time is longer with electrodessication, this modality represents an inexpensive practical ablative treatment method for actinic cheilitis. [source] Fractional CO2 laser: a novel therapeutic device upon photobiomodulation of tissue remodeling and cytokine pathway of tissue repairDERMATOLOGIC THERAPY, Issue 2009F. Prignano ABSTRACT Minimally ablative fractional laser devices have gained acceptance as a preferred method for skin resurfacing. Notable improvements in facial rhytides, photodamage, acne scarring, and skin laxity have been reported. The aim of the present work was to compare how different CO2 laser fluences, by modulating the secretory pathway of cytokines, are able to influence the wound-healing process, and how these fluences are associated with different clinical results. Eighteen patients, all with photodamaged skin, were treated using a fractional CO2 laser (SmartXide DOT, Deka M.E.L.A., Florence, Italy) with varying laser fluences (2.07, 2.77, and 4.15 J/cm2). An immunocytochemical study was performed at defined end points in order to obtain information about specific cytokines of the microenvironment before and after treatment. The secretory pathway of cytokines changed depending on the re-epithelization and the different laser fluences. Different but significant improvements in wrinkles, skin texture, and hyperpigmentation were definitely obtained when using 2.07, 2.77, and 4.15 J/cm2, indicating fractional CO2 laser as a valuable tool in photorejuvenation with good clinical results, rapid downtime, and an excellent safety profile. [source] Predictive values for aspiration after endoscopic laser resections of malignant tumors of the hypopharynx and larynxHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2004Manuel Bernal-Sprekelsen MD Abstract Background. CO2 -laser surgery is a relatively new treatment for selected carcinomas of the upper aerodigestive tract. The purpose of our study was to evaluate prospectively the functional results for swallowing after C02 -laser resections. Methods. The sample was composed of 210 consecutive patients with malignancies of the larynx and hypopharynx treated with CO2 laser between February 1998 and January 2002. Endoscopic resections included all T1 and T2 tumors and selected T3 and T4 tumors. T1 glottic tumors were not included in the analysis. We assessed the need for a feeding tube and the period the tube remained in place, aspiration pneumonia, tracheotomy secondary to aspiration, the need for a permanent or temporary gastrostomy, and total laryngectomy secondary to aspiration. Results. The nasogastric feeding tube was used in 23.2% of small tumors (2.5 ± 8.04 days) and in 63% of locally advanced tumors (13.95 ± 22.55 days). Frequency and period of storage of the feeding tube were higher in locally advanced tumors (p = .0001). Twelve patients (5.7%) had postoperative pneumonia and 59 (28.1%) had temporary postoperative cough during oral intake. Aspiration symptoms correlated with location (p = .001) and locally advanced tumors (p = .016). Eight patients (3.8%) needed a postoperative tracheotomy for severe swallowing difficulties; six (2.9%) of them were definitive and two (0.95%) temporary. Thirteen gastrostomies (6.2%) were performed to avoid severe aspirations; five of them were definitive. The need for gastrostomy correlated significantly with location (p = .002), pT3 and pT4 tumors (p = .002), age (p = .02), and postoperative radiotherapy (p = .04). No correlation was found with the period of feeding tube (p = .38), or aspiration pneumonia (p = .24). Conclusions. Endoscopic resection of laryngeal and hypopharyngeal tumors is associated with good recovery of deglutition. Many tracheotomies are avoided, the need for a feeding tube is usually reduced, and organ preservation is often feasible even in locally advanced tumors. © 2003 Wiley Periodicals, Inc. Head Neck26: 103,110, 2004 [source] Lasers for facial rejuvenation: a reviewINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2003Evangelia Papadavid MD Background Different types of laser are used for resurfacing and collagen remodeling in cutaneous laser surgery. Methods A systematic review was performed of the different types of laser currently employed for skin rejuvenation. These systems are either ablative [high-energy pulsed or scanned carbon dioxide (CO2) laser emitting at a wavelength of 10,600 nm, single- or variable-pulse or dual ablative/coagulative mode erbium:yttrium aluminum garnet (Er:YAG) laser emitting at a wavelength of 2940 nm, or systems combining both 10,600 nm and 2940 nm wavelengths] or nonablative [Q-switched neodymium:yttrium aluminum garnet (Nd:YAG) laser emitting at a wavelength of 1064 nm, Nd:YAG laser emitting at a wavelength of 1320 nm, or diode laser emitting at a wavelength of 1450 nm]. Different protocols, patient selection, treatment techniques, and complications are discussed for each system. Results New-generation CO2 resurfacing lasers have been successful in the treatment of photodamaged skin and scarring, with a postoperative morbidity dependent on the depth of thermal damage. Because of its minimal penetration, the pulsed Er:YAG laser, usually used in the treatment of more superficial rhytides, produces less postoperative morbidity. Novel ablative systems have been developed and a further understanding of laser,tissue interaction has led to the design of nonablative systems for the treatment of rhytides, scarring, and photodamaged skin, the efficacy and profile of which remain to be evaluated in the long term. Conclusions There are several effective techniques for scar revision and the treatment of aged skin, but all have their drawbacks due to a lack of precise depth control and unwanted damage to the lower layers of the dermis. The Er:YAG laser is the treatment of choice for fine lines and superficial scars, whereas the CO2 laser is better for deeper rhytides and scars. In the future, a combination of lasers may be used for facial rejuvenation. [source] Unifocal Langerhans cell histiocytosis of the oral mucosaJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 7 2009Susanna Fistarol Summary A 24-year-old man was admitted for a painful gingival ulcer. Histology and immunohistochemistry of a lesional biopsy revealed the diagnosis of Langerhans cell histiocytosis (LCH). To rule out multifocal disease, a complete staging was performed. There was no evidence of bony lesions or any other organ involvement. The diagnosis of LCH restricted to the oral mucosa was established. The complete oral lesion was ablated by CO2 laser and subsequently treated topically with triamcinolone acetonide. The patient is still in remission after one year of follow-up. LCH confined to the oral mucosa is rare. It presents usually as an inflammatory or ulcerative lesion, easily leading to misinterpretation and delayed diagnosis. Patients with limited unifocal mucocutaneous disease, as in the present case, usually have an excellent prognosis. However, the oral lesion may represent an early sign of LCH, predating and progressing to an aggressive life-threatening multiorgan disease. [source] Experiment and simulation on interface shapes of an yttrium aluminium garnet miniature molten zone formed using the laser-heated pedestal growth method for single-crystal fibersJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2009P. Y. Chen A two-dimensional simulation was employed to study the melt/air and melt/solid interface shapes of the miniature molten zone formed in a laser-heated pedestal growth (LHPG) system. Using a non-orthogonal body-fitting grid system with the control-volume finite-difference method, the interface shape can be determined both efficiently and accurately. During stable growth, the dependence of the molten-zone length and shape on the heating CO2 laser is examined in detail under both the maximum and the minimum allowed powers with various growth speeds. The effect of gravity on the miniature molten zone is also simulated and the possibility of horizontally oriented LHPG is revealed. Such a horizontal system is good for the growth of long crystal fibers. [source] Behavior of human periodontal ligament cells on CO2 laser irradiated dentinal root surfaces: an in vitro studyJOURNAL OF PERIODONTAL RESEARCH, Issue 6 2004V. Pant Objective:, The aim of this study was to investigate the in vitro attachment behavior of human periodontal ligament fibroblasts on periodontally involved root surface after conditioning with CO2 laser and to compare its efficacy with chemical conditioning agents, namely tetracycline hydrochloride, citric acid, hydrogen peroxide (H2O2) and EDTA, using scanning electron microscopy. Methods:, A total of 84 scaled and root-planed specimens from periodontally involved single-rooted human teeth showing hopeless prognosis were selected and assigned to two groups. One group was lased with a CO2 laser (from 5 cm at 3 W for 0.8, 1.0 and 1.2 s), and the other group was treated with either tetracycline hydrochloride (2.5%), citric acid (saturated solution, pH 1), H2O2 (6%) or EDTA (5%; pH 7.4) for 3 min. The specimens were then seeded with human periodontal ligament fibroblasts, incubated for either 12 h or 24 h, and then the cell attachment behavior was observed. Results:, CO2 laser irradiation for 1.0 s was found to be the most efficient, showing consistently good cell attachment with the highest mean value (15.00 ± 3.41 cells/10,000 µm2 after incubation for 12 h and 29.17 ± 2.04 cells/10,000 µm2 after 24 h), followed by irradiation for 0.8 s (13.11 ± 3.04 cells/10,000 µm2 after incubation for 12 h and 22.91 ± 7.10 cells/10,000 µm2 after 24 h). Charring was observed following irradiation for 1.2 s. Amongst chemical conditioning agents, citric acid was found to be the most efficient, with a mean cell attachment of 17.82 ± 2.16 cells/10,000 µm2 after incubation for 12 h and 23.62 ± 1.94 cells/10,000 µm2 after 24 h. EDTA and H2O2 did not do well in the study. Conclusion:, The results suggest that CO2 laser irradiation for 1.0 s may promote comparatively better attachment of periodontal ligament fibroblast on dentinal root surfaces than the conventional chemical conditioning agents used in the study. [source] Synthesis of hafnium tungstate by a CO2 laser and its microstructure and Raman spectroscopic studyJOURNAL OF RAMAN SPECTROSCOPY, Issue 7 2008E. J. Liang Abstract Densely packed hafnium tungstate blocks were synthesized by rapid solidification with a CO2 laser. It is shown that the optimum synthesis conditions for HfW2O8 are around 700 W laser power and 1 mm/s scan speed. Scanning electron microscopy (SEM) observation shows that the blocks consist of oriented nano-threads/rods that grew horizontally on the surface region and vertically in the interior. The orientations of the nanostructures are governed by the heat transfer directions on the surface and in the interior. Raman spectroscopic and X-ray diffraction studies show that the samples solidified in the cubic structure with minor contents of the orthorhombic phase. This is explained by a compressive stress induced during the rapid solidification process due to a sudden drop of temperature of the molten pool to the ambient. The stress is estimated to be about 0.6 GPa by comparison with high-pressure Raman study. Some specific Raman bands appear in the samples synthesized with the laser synthetic route but not in the sample by solid-state reaction. Copyright © 2008 John Wiley & Sons, Ltd. [source] Raman spectroscopic study on the structure, phase transition and restoration of zirconium tungstate blocks synthesized with a CO2 laserJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2007E. J. Liang Abstract Densely packed zirconium tungstate blocks were synthesized by rapid solidification with a CO2 laser. The structure and phase transition properties of the samples were studied by Raman spectroscopy and X-ray diffraction. Raman spectroscopic study reveals that zirconium tungstate solidifies with an orthorhombic structure. This is attributed to the pressure encountered by the samples during rapid solidification. Several Raman bands change discontinuously at about 390 K, indicating a phase transition from the ,- to the ,-phase occurring at this temperature. In the ,-phase, most of the Raman modes give rise to negative Grüneisen parameters, suggesting contribution of the corresponding optical phonons to the negative thermal expansion coefficient of the material, at least for the ,-phase. A recovery of the ,-phase was observed when the samples were cooled to room temperature. This suggests that the cubic structure is metastable only at temperatures above 390 K, and at room temperature the ,-phase is preferred. Copyright © 2007 John Wiley & Sons, Ltd. [source] Experimental study of sealed off operation of a high repetition rate TEA CO2 laserLASER PHYSICS LETTERS, Issue 10 2006M. J. Torkamany Abstract Design and construction of a high repetition rate low average power TEA CO2 laser with ultra violet pre ionization is presented. Replacing thyratron with a high voltage semiconductor switch and magnetic pulse compressor considering the highest peak power achievable is investigated. When using semiconductors as main switch of laser excitation circuit the output energy and laser power is lower about 5,10% relative to thyratron excitation circuit but the sealed off operation of laser is more uniform. (© 2006 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Pulpal effects of enamel ablation with a microsecond pulsed ,,=,9.3-µm CO2 laserLASERS IN SURGERY AND MEDICINE, Issue 4 2009Michal Staninec DDS Abstract Background and Objectives In vitro studies have shown that CO2 lasers operating at the highly absorbed 9.3 and 9.6-µm wavelengths with a pulse duration in the range of 10,20-microsecond are well suited for the efficient ablation of enamel and dentin with minimal peripheral thermal damage. Even though these CO2 lasers are highly promising, they have yet to receive FDA approval. Clinical studies are necessary to determine if excessive heat deposition in the tooth may have any detrimental pulpal effects, particularly at higher ablative fluencies. The purpose of this study was to evaluate the pulpal safety of laser irradiation of tooth occlusal surfaces under the conditions required for small conservative preparations confined to enamel. Study Design/Materials and Methods Test subjects requiring removal of third molar teeth were recruited and teeth scheduled for extraction were irradiated using a pulsed CO2 laser at a wavelength of 9.3 µm operating at 25 or 50 Hz using a incident fluence of 20 J/cm2 for a total of 3,000 laser pulses (36 J) for both rates with water cooling. Two control groups were used, one with no treatment and one with a small cut made with a conventional high-speed hand-piece. No anesthetic was used for any of the procedures and tooth vitality was evaluated prior to treatment by heat, cold and electrical testing. Short term effects were observed on teeth extracted within 72 hours after treatment and long term effects were observed on teeth extracted 90 days after treatment. The pulps of the teeth were fixed with formalin immediately after extraction and subjected to histological examination. Additionally, micro-thermocouple measurements were used to estimate the potential temperature rise in the pulp chamber of extracted teeth employing the same irradiation conditions used in vivo. Results Pulpal thermocouple measurements showed the internal temperature rise in the tooth was within safe limits, 3.3±1.4°C without water cooling versus 1.7±1.6°C with water-cooling, n,=,25, P<0.05. None of the control or treatment groups showed any deleterious effects on pulpal tissues and none of the 29 test-subjects felt pain or discomfort after the procedure. Only two test-subjects felt discomfort from "cold sensitivity" during the procedure caused by the water-spray. Conclusion It appears that this CO2 laser can ablate enamel safely without harming the pulp under the rate of energy deposition employed in this study. Lasers Surg. Med. 41:256,263, 2009. © 2009 Wiley-Liss, Inc. [source] Complications of fractional CO2 laser resurfacing: Four casesLASERS IN SURGERY AND MEDICINE, Issue 3 2009Douglas J. Fife MD Abstract Background and Objective Fractional ablative laser therapy is a new modality which will likely be widely used due to its efficacy and limited side-effect profile. It is critical to recognize, characterize, and report complications in order to acknowledge the limits of therapeutic efficacy and to improve the safety of these devices. Study Design/Materials and Methods The photographs, treatment parameters, and clinical files of four female patients aged 54,67 who had scarring or ectropion after fractional CO2 laser resurfacing on the face or neck were carefully reviewed to search for any possible linking factors. Results Patient 1 developed erosions and swelling of the right lower eyelid 2 days postoperatively, which developed into scarring and an ectropion. Patient 2 developed linear erosions and beefy red swelling on the right side of the neck which developed into a tender, band-like scar over 1-month. Patient 3 developed stinging and yellow exudate in multiple areas of the neck 3 days postoperatively. Cultures grew methicillin-resistant Staphylococcus aureus. Despite appropriate treatment, she developed multiple areas of irregular texture and linear streaking which developed into scars. Patient 4 developed an asymptomatic patchy, soft eschar with yellowish change on the left side of the neck. Azithromycin was started, however at 2-week follow-up she had fibrotic streaking which developed into horizontal scars and a vertical platysmal band. The treatment and final outcome of each patient are described. Conclusion Scarring after fractional CO2 laser therapy may be due to overly aggressive treatments in sensitive areas (including excessive energy, density, or both), lack of technical finesse, associated infection, or idiopathic. Care should be taken when treating sensitive areas such as the eyelids, upper neck, and especially the lower neck and chest by using lower energy and density. Postoperative infections may lead to scarring and may be prevented by careful taking of history, vigilant postoperative monitoring and/or prophylactic antibiotics. Lasers Surg. Med. 41:179,184, 2009. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||