532-nm KTP Laser Research Articles

Photoangiolytic Lasers for Treatment of Benign Laryngeal Lesions: A Systematic Review and Meta-Analysis.

To compare the efficacy of the 445-nm blue laser to the 585-nm pulsed dye laser (PDL) and 532-nm potassium-titanyl-phosphate (KTP) laser in the treatment of benign laryngeal lesions. Cochrane Library, PubMed, Scopus, and CINAHL. Following PRISMA guidelines, databases were searched from inception through January 29, 2024, for studies reporting the use of photoangiolytic lasers for treatment of benign laryngeal lesions, including the 585-nm PDL, 532-nm KTP laser, and 445-nm blue laser. Outcome measures included lesion resolution (%), mean differences (Δ) in Voice Handicap Index (VHI-10), and summed dysphonia grade, roughness, and breathiness (GRB) scale. A total of 45 studies were included for meta-analysis, consisting of 348 patients treated with PDL, 550 patients with KTP laser, and 338 patients with blue laser. Treatment with blue laser resulted in the greatest lesion resolution (94.0%; 95% confidence interval [CI]: 90.2%-96.7%), followed by KTP laser (90.4%; 95% CI: 84.1%-95.2%), and PDL (86.9%; 95% CI: 62.9%-99.2%). VHI-10 improved significantly in patients following treatment with blue laser (Δ13.3; 95% CI: 10.7-16.0; p < 0.0001), KTP laser (Δ10.3; 95% CI: 7.4-13.3; p < 0.0001), and PDL (Δ7.4; 95% CI: 4.8-10.1; p < 0.0001). GRB improved significantly in patients following treatment with blue laser (Δ4.1; 95% CI: 2.9-5.2; p < 0.0001), KTP laser (Δ3.0; 95% CI: 2.0-4.0; p < 0.0001), and PDL (Δ2.5; 95% CI: 0.8-4.2; p = 0.005). Photoangiolytic lasers are effective in treating benign laryngeal lesions. Blue lasers are promising for laryngeal laser surgery. Laryngoscope, 2024.

Office-based 532-nm KTP laser as a therapeutic modality for recurrent laryngeal papillomatosis: efficacy and relative factors.

This study aims to investigate the efficacy of office-based potassium-titanyl-phosphate (KTP) 532-nm laser in the management of recurrent laryngeal papillomatosis (RLP) following other treatments. A retrospective assessment was performed on 55 patients in 259 cases of RLP between 2012 and 2019. Derkay scores were obtained for all patients who underwent 532-nm KTP laser procedure (6 W of power with a continuous output mode) prior to treatment and after treatment. Analysis of parameters is based on the distribution characteristics of data. An ordinal logistic regression was also performed. Patients received a median of 3 (range 1-24) office-based KTP laser treatments. Among them, 96.36% (53 patients) were previously on cold steel equipment, CO2 laser, or microdebrider treatment under general anesthesia, and all previous treatments on them had failed. One patient progressed to invasive cancer, so he was excluded from the following analyses. After final KTP treatment, 36 patients (66.67%) received complete resolution with follow-up time ranging from 12.9 to 80.53months (median 55.54months). Results of subjective voice-quality indicators such as VHI-30 and GRBAS all improved greatly at the last follow-up. The initial Derkay scores and treatment intervals were found to be predictive of complete lesion remission. Arytenoid involvement may also correlate with lesion resolution. Serial office-based KTP treatment is an effective option for RLP patients, with ideal disease control and voice quality preservation. KTP laser therapy should be repeated with an interval of 1month from the beginning of treatment until the lesion has been evaluated and subsided. Non-bulk or scattered laryngeal papilloma is an appropriate indication for KTP laser treatment.

The use of the KTP 532 nm vascular laser in the treatment of erythema and telangiectasia caused by low temperature exposure - case report

The use of the KTP 532 nm vascular laser in the treatment of erythema and telangiectasia caused by low temperature exposure - case report. A case report. The paper presents a case of effective treatment of frostbite vascular lesions in the face with the use of a 532nm KTP laser in a 55-year-old man with a long history of skin exposure to low temperatures. Aim. The aim of this study is to draw attention to the possibility of using laser therapy in the treatment of skin disorders that are a complication of exposure to low temperatures. In the article below, we present the reduction of vascular lesions of the facial skin during a series of laser treatments with the use of the 532nm laser, meeting the growing interest of patients and doctors in the use of laser therapy in the treatment of skin vascular lesions. Conclusions. The use of laser therapy with the KTP 532nm laser can be an important and effective element in the treatment of skin vascular lesions.

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

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. 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. 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. 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. 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.

Treatment of telangiectasia on the cheeks with a compact yellow (585 nm) semiconductor laser and a green (532 nm) KTP laser: a randomized double-blinded split-face trial.

The primary objective of this study was to compare a traditional green KTP laser to a new investigational yellow laser (PhotoLase) in the treatment of facial telangiectasia in terms of the treatment outcomes. The secondary objective was to assess the functionality and reliability of the PhotoLase system from the perspective of the user. The study was a randomized split-face double-blinded study that compared the treatment efficacy of the 532-nm KTP laser and the investigational 585-nm PhotoLase laser. One or two treatments were given based on the response of the first treatment. The improvement of telangiectasia was graded according to a 7-point Telangiectasia Grading Scale (TGS) by the subjects and blinded physicians. The subjects assessed the amount of pain during the treatments using Visual Analogue Scale (VAS), and evaluated adverse effects 2-3 days after the treatment(s) using a self-assessment form. At least 50% improvement was seen in 15/18 subjects after the first PhotoLase treatment, and a similar result was observed for KTP, as assessed by the blinded physicians (P = 0.29). In the subjects' assessment, 7/18 subjects had at least 50% improvement after the first PhotoLase treatment, whereas at least 50% improvement was observed for 10/18 subjects in the KTP side, the difference being significant (P = 0.008). The amount of pain was higher with PhotoLase compared to KTP (67.7 vs. 34.6, P < 0.001). There was no difference in the frequency of erythema, crusting or purpura between the devices, but more blistering and less edema were seen after PhotoLase treatment (P < 0.05). Treatment with PhotoLase was evaluated to be 4.7-fold faster than with KTP and the PhotoLase system was more compact, narrower, lighter, and easier to carry than KTP. The investigational PhotoLase laser enables significantly faster treatments, but the process is somewhat more painful than with KTP, otherwise providing a similar clinical outcome in the treatment of facial telangiectasia. Treatment Protocol Lasers Surg. Med. 51:223-229, 2019. © Wiley Periodicals, Inc.

Surgical Treatment of Sulcus Vocalis Using KTP Laser

Sulcus vocalis remains a surgical challenge despite many recent advances in laryngomicrosurgeries. We previously reported that 585-nm Pulsed dye laser (PDL) exerts favorable outcome in treatment of sulcus vocalis due to its therapeutic effects of collagen rearrangement and improved wound remodeling. In spite of the usefulness of PDL glottoplasty for treating sulcus vocalis, the device is no more available in the country. It prompted us to focus another angiolytic laser ; 532-nm KTP laser which has similar mechanisms of action and has been used for treatment of other laryngeal lesions elsewhere. Herein, we present a case of sulcus vocalis successfully treated with KTP laser. A patient underwent laryngomicrosurgery with angiolytic KTP laser (KTP glottoplasty) by the same surgical procedure with PDL glottoplasty. After the surgery, the patient presented improved voice outcome in time without complications. Key words: Sulcus vocalis ㆍ Voice disorders ㆍ Phonosurgery ㆍ Laryngoscopic surgery ㆍ KTP glottoplasty 핵심용어: 성대구증 ㆍ 음성질환 ㆍ ìŒì„±ìˆ˜ìˆ ã† í›„ë‘ë¯¸ì„¸ìˆ˜ìˆ ã† KTP 성대구수ìˆ

Proposed classification system for reporting 532‐nm pulsed potassium titanyl phosphate laser treatment effects on vocal fold lesions

Currently, no standard exists for reporting treatment results for the potassium titanyl phosphate (KTP) laser. The goal of this study was to establish a validated classification schema for reporting immediate tissue effects after laser treatment. Evaluation of KTP laser video sequences by academic laryngologists with use of the rating system. A five-point classification system was developed; this included noncontact angiolysis, epithelial blanching, epithelial disruption, contact epithelial ablation, and contact epithelial ablation with tissue removal. Video recordings were made prospectively for each treatment effect. Ten treatment recordings, with two repeated recordings, were presented to seven academic laryngologists, who were asked to categorize each based on the given classification scheme. Overall accuracy for the combined reviewers in rating the treatments was 82%. Six of seven reviewers showed perfect intrarater reliability. Accuracy in rating clips did not correlate with the previous number of 532-nm KTP or 585-nm pulsed dye laser procedures performed but showed a trend toward correlating with total years in practice. This study reveals that standardized reporting of effects of the KTP laser is feasible. We believe that results of KTP treatment should be reported using a validated classification system of immediate laser effect, along with specific laser settings. This classification system allows for future systematic evaluation of long-term treatment results prospectively from single laser treatments.

Evaluating the Effects of a 532‐nm Fiber‐Based KTP Laser on Transoral Laser Surgery Supplies

The KTP laser has become commonplace in transoral head and neck surgery. The interactions of this laser with commonly used supplies in transoral surgery have not been formally examined. This study evaluates the effects of the KTP laser on surgical supplies. Experimental study. The study was conducted in an empty operating room at a university-affiliated medical center. An Aura XP 532-nm KTP laser with a 600-nm fiber was used in pulsed and continuous modes. The beam was focused at the shaft and balloon of 3 "laser-safe" endotracheal tubes (ETTs), a polyvinyl chloride (PVC) ETT, and a Codman surgical patty. Time to penetrate was recorded. Results The KTP laser beam was unable to penetrate any of the laser-resistant ETTs. It did react with the black number markings on the PVC ETT by producing sparks but was unable to penetrate the shaft of the ETT. The KTP laser was nonreactive with all ETT cuffs except in 1 of 3 trials with the outer balloon cuff of a Rusch Lasertubus ETT when the laser was used in a continuous mode. The KTP laser caused the production of a flame upon contact with the blue radiopaque strip of the surgical patty, even when the patty was wet. This study demonstrates that a number of safe ETT options may be used during transoral laser microsurgery with a KTP laser. In addition, Codman surgical patties are shown to be a significant fire risk in KTP laser surgery.

Treatment of superficial vascular lesions with the KTP 532-nm laser: experience with 647 patients

Superficial vascular lesions are a common dermatological diagnosis but are often difficult to treat. Numerous lasers (especially the dye laser) and intense pulsed light sources have been used, but there have been very few reports on the effectiveness of the potassium-titanyl phosphate (KTP) laser. We have extensive experience of this modality at our institution, and the purpose of this survey is to report on the safety and efficacy of the KTP laser. Using an in-house database, we retrospectively collected data from patients who had undergone treatment with the KTP laser for superficial vascular lesions. Patients of Fitzpatrick skin type I-IV were included. Exclusion criteria were Fitzpatrick skin type V, patients with obvious suntan and those on potentially phototoxic medications or minocycline therapy. Diagnoses included discrete or matted telangiectasia, strawberry naevus, spider angioma, rosaceal erythema, rosaceal telangiectasia, telangiectatic naevus, angioma, combined rosaceal erythema/telangiectasia, port-wine stain, venous lake haemangioma and hereditary haemorrhagic telangiectasia. Patients underwent an initial test treatment and further treatment at 6-week intervals as required. Clinical photographs were taken pre- and post-treatment, and outcome was graded by patient and physician. Adverse effects were recorded including scarring, hypo- or hyperpigmentation, marked swelling, blistering, scabbing and bruising. Six hundred forty-seven patients with 13 diagnoses on 9 different body sites were recorded. Four hundred eighty-six were female, and the median age was 39.5years. Of the lesions treated, 33.7% (n = 218) were discrete telangiectases and 31.8% (n = 206) were spider angiomas. A 92.7% of lesions were on the face. Four hundred thirteen (77.6%) patients who had outcomes recorded at 6weeks were graded as "clearance" or "marked improvement". Only 38 (5.8%) patients experienced adverse effects, all of which were minor; the main adverse effect was swelling. Unlike the dye laser, there was only one case of bruising out of 647 patients. This is the largest survey of patients to have undergone KTP laser treatment reported in the literature. Our results show that the KTP laser is a safe and effective modality for the treatment of superficial vascular lesions.

Voice Outcomes for Photoangiolytic KTP Laser Treatment of Early Glottic Cancer

Surgery and radiotherapy routinely provide high cure rates in treating early glottic cancer. Therefore, key metrics for success are optimal voice outcome and preservation of future cancer treatment options. Remarkably, there is a paucity of pretreatment versus posttreatment voice outcome data. Angiolytic KTP (potassium titanyl phosphate) laser treatment of early glottic cancer with ultranarrow margins was initiated to better preserve vocal function. Given that effective oncological results have been achieved, it was hypothesized that this approach would also result in improved posttreatment measures of vocal function that more closely approximate historical norms than pretreatment values. Pretreatment and posttreatment voice outcome data were obtained for 92 patients (64 with T1 cancer and 28 with T2 cancer) who underwent 532-nm KTP laser treatment of early glottic cancer in a study design in which each patient essentially served as his or her own control. The evaluations included objective measures (acoustic and aerodynamic) and patients' self-assessments of vocal function (Voice-Related Quality of Life; V-RQOL). A series of mixed analyses of variance were conducted for all vocal function measures, with tumor stage and depth of invasion as the between-subjects variables and time (presurgery versus postsurgery) as the within-subject variable. There were statistically significant (p < or = 0.05) postoperative improvements for acoustic (perturbation and noise-to-harmonics ratio) and aerodynamic (subglottic pressure and vocal efficiency) measures of vocal function, as well as for V-RQOL assessment. Comprehensive pretreatment and posttreatment voice measures in a large patient cohort demonstrated that the KTP laser significantly improved postoperative vocal function in patients with early glottic cancer. Furthermore, radiotherapy was preserved as an oncological treatment option.

Effect of the 532nm pulsed KTP laser in the treatment of Reinke's edema

To evaluate the effect and safety of the 532nm Pulsed Potassium-Titanyl-Phosphate (KTP) laser in the office-based treatment of patients with Reinke's edema using objective and subjective scaled outcome measures. Case Series. Tertiary hospital center. Seven adult females undergoing in-office KTP laser treatment for Reinke's edema. Participants were studied pre- and posttreatment. Vocal function was evaluated by objective aerodynamic and acoustic analysis. Subjective changes were evaluated using the GRBAS scale, Voice Handicap Index, and videostroboscopy. Histologic effects of the laser were investigated by comparing one patient treated with laser one year prior to excision, one treated with laser just prior to excision, and one control patient who underwent excision without prior laser treatment. At an average postoperative follow up of 17.8 weeks (range 5-78), maximum phonation time trended toward improvement. The median VHI score decreased from 37 to 26 (p=0.150). There was a reduction in each component of the GRBAS scoring and the median fundamental frequency increased from 162 to 186 (p=0.625). Stroboscopic findings demonstrated an intact posttreatment mucosal wave. Histologic comparison of the tissue effects of laser in three patients demonstrated changes in vocal fold vascularity but no acute or long-term damage to the overlying epithelium. Objective and subjective scaled measures suggest that treatment of Reinke's edema in the office with a 532nm KTP laser may result in improved voice. It appears safe with histologic preservation of the vocal fold vibratory epithelium and persistence of mucosal wave.

Evaluation of 532-nm KTP laser treatment efficacy on acne vulgaris with once and twice weekly applications

Background: Light-based therapies and lasers have been proposed for the treatment of acne vulgaris but the efficacy and application periods of 532-nm KTP laser treatment are not clear. Objective: To evaluate the efficacy and safety of 532-nm KTP laser and compare the effects of once and twice weekly applications in the treatment of mild to moderate acne vulgaris. Methods: Totally 38 patients were treated once weekly and twice weekly in group I and in group II respectively. One half of the face of each patient was treated with 532-nm KTP and the other half was remained as untreated. Patients were evaluated at the beginning, one and four weeks after the last treatment session with Michaëlsson acne severity grading score (MASS). Results: Statistically significant improvement was found at second control (p = 0.005) in group I, and at the first (p = 0.004), and second (p < 0.001) controls in group II for treated sides. For both groups, changes of MASS were insignificant for untreated sites. Improvement of MASS of treated sides was not statistically significant between two treatment groups for both controls. Conclusion: 532-nm KTP laser treatment may be an alternative method in selected acne vulgaris patients. No significant difference was noted between once and twice weekly applications.

Local Injection of Bevacizumab (Avastin) and Angiolytic KTP Laser Treatment of Recurrent Respiratory Papillomatosis of the Vocal Folds: A Prospective Study

Photoangiolytic laser treatment of recurrent respiratory papillomatosis (RRP) is effective, but does not reliably prevent recurrence. Therefore, sublesional injections of the antiangiogenic agent bevacizumab (Avastin) were given to assess the adjunctive effect on disease recurrence. Since bevacizumab is a new therapeutic modality for RRP, there were also primary safety objectives to determine whether there was a pegative impact on the voice and whether there were local or systemic complications. A prospective open-label investigation was conducted in 20 adult patients with bilateral vocal fold RRP. The patients underwent planned 532-nm pulsed KTP laser photoangiolysis of bilateral glottal disease 4 times with an approximately 6-week interval between procedures. At each planned laser procedure, the vocal fold that on initial presentation had a greater volume of disease also underwent 4 serial sublesional bevacizumab injections (7.5 to 12.5 mg in 0.3 to 0.5 mL). A sham injection with saline solution was administered to the other vocal fold as a control. Disease resolution was compared between subjects' vocal folds, and objective measures of vocal function (acoustic, aerodynamic), as well as patients' self-assessments of vocal function (Voice-Related Quality of Life survey), were obtained. All 20 patients completed the study, and there were no local or systemic complications. After 4 injections, 3 of the 20 patients had no discernible disease in either vocal fold. Of the remaining 17 subjects, 16 had less disease in the bevacizumab-treated vocal fold despite starting with more disease. Only 1 of the 17 had more disease in the bevacizumab-treated vocal fold after 4 injections. Moreover, 7 of the 20 patients (35%) did not require a laser procedure in the vocal fold that had received 4 bevacizumab injections, as compared with 3 of the 20 vocal folds (15%) that were treated with laser alone. All of the vocal function measures displayed statistically significant posttreatment improvements, except for average fundamental frequency in the 3 female patients, in whom it fell below the normal range. This prospective investigation provided evidence that bevacizumab injections enhanced KTP laser treatment of glottal papillomatosis without systemic or local complications. Coupling the antiangiogenesis agent bevacizumab with KTP laser photoangiolysis is conceptually synergistic and scientifically promising since the mechanisms of action are complementary.

Prevention of Thyroidectomy Scars in Asian Adults Using a 532-nm Potassium Titanyl Phosphate Laser

Prediction of whether postoperative wound healing will result in a hypertrophic scar or keloid is difficult. Diverse treatment options have been developed in an effort to prevent excessive scar formation. To evaluate the efficacy and safety of a 532-nm potassium titanyl phosphate (KTP) laser in the prevention of scar formation after total thyroidectomy. Twenty-eight individuals with Fitzpatrick skin types IV and V and linear surgical suture lines after total thyroidectomy by the same surgeon were enrolled. Twenty participants were treated using a 532-nm KTP laser two times at 2-week intervals. Eight participants were assigned to the control group. The Vancouver Scar Scale (VSS), global assessment score (GAS), and participants' subjective satisfaction were used to determine the effect of scar prevention. These results were compared with those of the control group. The average VSS score was remarkably lower in the KTP laser treatment group. Average GASs indicated better cosmetic outcomes in the treatment group. Participant satisfaction was also higher in the treatment group. No significant side effects were observed during follow-up. A 532-nm KTP laser can be used safely and efficiently on Asian skin to reduce scar formation after thyroidectomy. The authors have indicated no significant interest with commercial supporters.

532‐nanometer potassium titanyl phosphate (KTP) laser‐induced expression of selective matrix metalloproteinases (MMP) in the rat larynx

The 532-nm KTP laser is clinically useful to induce benign vocal fold lesion regression without a fibrotic response. Previously, we described an in vivo model for KTP-induced injury in the rat larynx. This study uses this model to correlate the KTP-induced histologic and biochemical changes with the absence of long-term vocal fold fibrosis seen in clinical scenarios. In vivo. Unilateral vocal fold injury was induced via KTP laser at 10W (20mS pulse width) as described by our laboratory previously. Animals were subjected to serial endoscopic imaging from postoperative days 1 through 3. Animals were euthanized at 1 day, 4 weeks, and 12 weeks posttreatment and subjected to histologic analyses via hematoxylin and eosin and trichrome staining, as well as RT-PCR analyses for MMP-3, 9, transforming growth factor-beta (TGF-β), and COX-2 mRNA expression. Uninjured vocal folds were used as controls. Our study revealed gross healing of the vocal fold mucosa by 3 days posttreatment, and an immediate, moderate inflammatory infiltrate with no subsequent ultrastructural changes on histology. MMP-3 and COX-2 expression increased transiently, although no changes were seen in expression of MMP-9, an MMP involved in extracellular matrix remodeling, or TGF-β, a profibrotic cytokine. These data suggest that the KTP laser induces a modest inflammatory response, selective MMP expression, and no long-term fibrotic processes in a clinically relevant simulation.

Continuous or fractionated photodynamic therapy? Comparison of three PDT schemes for ovarian peritoneal micrometastasis treatment in a rat model

This experimental study aimed to compare three illumination schemes to optimize hexaminolaevulinate (HAL)-PDT in a rat tumor model with advanced ovarian cancer. Peritoneal carcinomatosis was induced by intraperitoneal 5×10(6)NuTu-19 cells injection in 60 female rats Fisher 344. Carcinomatosis was obtained 50 days post-tumor induction. Four hours post-intraperitoneal HAL (Photocure ASA, Oslo, Norway) injection, three different schemes of PDT were performed during 25 min on a 1cm(2) area. (A) Fractionated illumination (n=20) with an on-off cycle ("on": 2 min and "off": 1 min) at 30mW cm(-2) until a fluence of 30J cm(-2), (B) continuous illumination (n=20) at 30mW cm(-2) with a fluence of (45J cm(-2)C) continuous illumination (n=20) at 20mW cm(-2) with a fluence of 30J cm(-2). Laser light was generated using a 532nm KTP laser (Laser Quantum, Stockport, UK). Biopsies were taken 24h after treatment. Quantitative histology was performed. Necrosis value was determined: 0-no necrosis to 4-full necrosis. Depth of necrosis was then measured for each sample and correlated to Necrosis value. HAL-PDT was efficient in producing necrosis irrespective of the scheme. Tumor destruction was superior with fractionated illumination compared to both continuous illumination schemes regarding to the depth of necrosis (213±113μm vs 154±133μm vs 171±155μm) (p<0.05) or to the full necrosis rate (50% vs 30% vs 10%) (p<0.0001). Fractionated illumination during photodynamic therapy (PDT) was shown to improve tumor response. Fractionated illumination with short intervals should be considered for an effective PDT of advanced ovarian cancer.

Clinical comparison of potassium-titanyl-phosphate (KTP) versus neodymium:YAG (Nd:YAG) laser treatment for lower extremity telangiectases

Background: The Nd:YAG laser has been considered the gold standard of treatment for leg veins, but pain and side effects have fueled physicians to use treatment alternatives. Objective: To compare the clinical efficacy of the long-pulsed 1064-nm Nd:YAG laser with KTP laser irradiation in the treatment of leg telangiectasia. Methods: A series of 16 patients with size-matched superficial telangiectases of the lower extremities were randomly assigned to receive three consecutive monthly treatments with the long-pulsed 1064-nm Nd:YAG on one leg and 532-nm KTP laser irradiation on the other. Results: For the 16 patients who completed the study, 64 leg vein sites were treated. Average clinical improvement scores were 1.94 and 1.25 for the KTP laser-treated leg and 3.38 and 3.50 for the Nd:YAG laser-treated leg with thin (≤ 1 mm) and large (1–3 mm) vessels, respectively. After the third treatment session, average improvement scores of 2.44, 1.31 and 3.75, 3.23 were given for the KTP and Nd:YAG laser-treated sides, respectively. Conclusion: Both the 1064-nm Nd:YAG and KTP lasers are effective in the treatment of lower extremity telangiectases. However, the KTP laser has very low efficacy with vessels larger than 1 mm and should not be elected when treating such vessels.

Microlaryngoscopic and Office-Based Injection of Bevacizumab (Avastin) to Enhance 532-nm Pulsed KTP Laser Treatment of Glottal Papillomatosis

Photoangiolytic lasers effectively treat glottal papillomatosis, but do not reliably prevent recurrence. Therefore, sublesional injections of the antiangiogenic agent bevacizumab (Avastin) were given to assess the effect on disease recurrence and phonatory function. A retrospective investigation was done in a pilot group of 10 adult patients with bilateral glottal papillomatosis who had prior angiolytic laser treatment with established patterns of recurrence. The patients underwent 5 bevacizumab injections (5 to 10 mg) into the diseased vocal folds along with 532-nm pulsed KTP laser photoangiolysis treatments 4 to 6 weeks apart. Their disease resolution was compared to findings from prior laser treatment alone, and objective measures of vocal function (acoustic, aerodynamic, Voice-Related Quality of Life survey) were obtained. All 10 patients had a greater than 90% reduction in recurrence. Four of the 10 had resolution. Four of the 10 have limited recurrent or persistent disease, receive injections of bevacizumab at 8- to 12-week intervals, and have not required laser treatment. Two of the 10 have ongoing periodic office-based KTP laser treatment along with bevacizumab injections. No patient has required microlaryngeal surgery with general anesthesia, and all 10 have had substantial improvement in vocal function. This pilot investigation provides preliminary evidence that bevacizumab injections enhance photoangiolytic laser treatment of glottal papillomatosis while enhancing phonatory function. Coupling an antiangiogenesis agent with pulsed KTP laser photoangiolysis is conceptually promising, since the mechanisms of action are complementary.

The efficacy of the dual wavelength Gemini laser on resistant port wine stains: a pilot study

Port wine stains (PWS) are vascular malformations resulting in ectatic blood vessels within the dermis. Laser treatment of port wine stains is based on selective photothermolysis of oxyhaemoglobin. Treatment is aimed at creating improvement of the port wine stain rather than complete eradication. A variety of different lasers are in use, all with their own limitations. The dual wavelength Gemini laser consists of a Nd:YAG 1,064-nm and a frequency-doubled KTP 532-nm laser. The Gemini offers the advantage of a larger spot size (10 mm), while maintaining the ability to deliver higher fluences. The large (10 mm) diameter spot size also allows an enhanced depth of penetration, enabling treatment of deeper vessels. To establish the efficacy of the Gemini laser on resistant port wine stains, we conducted a prospective study on five resistant port wine stains using the KTP component at 532 nm using 5- and 10-mm spot sizes. Improvement was seen in all patients. Areas treated with 10-mm spot size showed better improvement of the PWS compared to 5 mm spot size areas. In the case of treatment to a patient’s arm, response in the upper level of the limb was better than in the lower level. No adverse side effects were reported and discomfort was minimal. This pilot study demonstrates increased efficacy of the Gemini laser in the treatment of resistant port wine stains.

An open-label, split face study comparing the safety and efficacy of levulan plus a 532-nm KTP laser to a 532-nm KTP laser alone for the treatment of acne

An open-label, split face study comparing the safety and efficacy of levulan plus a 532-nm KTP laser to a 532-nm KTP laser alone for the treatment of acne