Use of lasers in laryngeal surgery

National Trends in Laryngeal Laser Surgery: Comparison of Operative Versus Office-Based Procedures

OBJECTIVE

To analyze national trends in the prevalence of office-based laryngeal ablative procedures and compare those with traditional operative excisional procedures utilizing direct laryngoscopy.

METHODOLOGY

For years 2013-2022, the US Medicare Part B claims database was searched for Current Procedural Terminology (CPT) codes 31572 (flexible laryngoscopy with laser ablation of lesion), 31540 (operative direct laryngoscopy with excision of lesion), 31541 (operative direct microlaryngoscopy with excision of lesion), and 31545 (operative direct microlaryngoscopy with excision of lesion and local tissue flap reconstruction). For each CPT code, the total number of charges billed to the Medicare database in each calendar year was recorded and annual trends were analyzed. Biopsy procedures were not included.

RESULTS

The annual number of office-based laser procedures (CPT 31572) remained relatively constant since the CPT code was introduced in 2017 (range: 18887-25241 procedures annually, trendline slope = +16, R2:0.02). Office-based laser procedures comprised a small portion of total laryngeal excisional procedures (range: 8.4%-12.1%). The total number of operative laryngeal excisions, billed by CPT 31540 and 31541, declined over the studied time frame (Trendline slope = -132, R2:0.93; Trendline slope = -950, R2: 0.93 respectively).

CONCLUSIONS

Office-based laser procedures comprise a small fraction of procedures to remove laryngeal lesions. The number of office-based laser procedures has been relatively stable over the last 5 years. This finding contrasts with the prevailing health care trend toward office-based procedures. Further research is needed to understand the decrease in operative laryngeal lesion excision procedures observed over the last 10 years.

LEVEL OF EVIDENCE

4 Laryngoscope, 135:823-828, 2025.

Does Intralesional Steroid Injection Effectively Mitigate Vocal Fold Scarring in A Rabbit Model?

OBJECTIVES

To assess the efficacy of intralesional steroid treatment in preventing vocal fold scarring following vocal fold surgery using a rabbit model.

METHODS

The research involved 42 male New Zealand white rabbits. Fourteen rabbits underwent vocal fold scar surgery using a 532nm laser and served as controls (control group). The remaining rabbits were divided into two groups of 14: one group received vocal fold scar surgery followed by dexamethasone injection (Dexa group) and the other received the same surgery followed by triamcinolone injection (Triam group). Four weeks after surgery, histological examinations and high-speed video analyses of vocal fold vibration were conducted. The maximum amplitude of vibration was the primary measure for assessing vocal fold function. In addition, real-time polymerase chain reaction (PCR) studies were undertaken to analyze scar regeneration and remodeling.

RESULTS

The maximum amplitude differences were notably higher in the Dexa and Triam groups than in controls. Histologically, the collagen density (CD) ratios in both the Dexa and Triam groups were significantly reduced compared with controls. Real-time PCR analysis indicated marked elevations of Has-2 and Mmp-9 in the Dexa and Triam groups relative to controls.

CONCLUSIONS

Intralesional steroid injections after vocal fold surgery are effective for reducing vocal fold scarring in a rabbit model.

LEVEL OF EVIDENCE

NA Laryngoscope, 135:176-182, 2025.

Systematic Review: Effectiveness of Carbon Dioxide Lasers for Treatment of Adult Laryngeal Hemangioma

IMPORTANCE

Adult laryngeal hemangiomas are rare and may cause symptoms such as dysphonia, dysphagia, and dyspnea. Carbon dioxide (CO2) lasers offer an alternative approach to managing this rare condition.

OBJECTIVE

The objective of this study is to evaluate the effectiveness of CO2 lasers in treating adult hemangioma and to identify potential side effects associated with this treatment modality.

DESIGN/METHODS

The study utilizes the PRISMA model to systematically collect articles available in the current literature. The numbers obtained from each academic manuscript were then used to calculate the effectiveness of CO2 laser therapy in patients with laryngeal hemangiomas. Articles from 1949 to 2023 were gathered using the PRISMA systematic review method.

SETTING

Not applicable.

PARTICIPANTS

Adult patients with laryngeal hemangioma who were treated with CO2 lasers.

INTERVENTION OR EXPOSURES

Surgical management with CO2 lasers.

MAIN OUTCOME MEASURES

Number of patients with at least a 50% reduction in laryngeal hemangioma size.

RESULTS

Two case reports, 4 case series, and 2 observational studies were included in this systematic review. For the case reports and series, only 1 out of the 19 patients experienced recurrence following CO2 laser treatment. However, some studies did not have adequate follow-up time. In the 2 observational studies, efficacy rates of 100% and 90.9% were reported by the authors respectively.

CONCLUSION AND RELEVANCE

Adult laryngeal hemangioma can be safely and successfully treated with CO2 laser microsurgery in well-selected cases. More studies, as well as longer patient follow-ups, are needed to truly assess the efficacy of CO2 laser in treating laryngeal hemangioma. This method provides a minimally invasive technique for adult patients with this rare disease.

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

OBJECTIVES

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.

DATA SOURCES

Cochrane Library, PubMed, Scopus, and CINAHL.

REVIEW METHODS

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.

RESULTS

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).

CONCLUSIONS

Photoangiolytic lasers are effective in treating benign laryngeal lesions. Blue lasers are promising for laryngeal laser surgery. Laryngoscope, 134:4847-4857, 2024.

Surgical Outcome of Low-Power-Density Blue Laser for Vascular Lesions of the Vocal Fold

Photoangiolytic lasers such as the 532-nm potassium-titanyl-phosphate (KTP) and the novel 445-nm blue laser (introduced into the United States in 2020) are absorbed selectively by hemoglobin, permitting targeted ablation of vascular structures such as vascular malformations of the vocal fold (VF). Previously, we reported the high rate of success of KTP laser photocoagulation for VF vascular lesions. Compared with other photoangiolytic lasers, blue laser has the highest absorption in hemoglobin, and therefore it can be operated at lower power densities to minimize thermal injury to adjacent tissue.

OBJECTIVE

The purpose of this study was to determine the efficacy and safety of blue laser for treatment of VF vascular lesions using low power densities, and to compare outcomes of blue laser with those of KTP laser.

METHODS

Adult voice patients who underwent blue laser treatment of VF vascular lesions in the operating room at the lowest power densities that appeared clinically to cause the effect desired were included in this retrospective study. Baseline lesion characteristics and postoperative outcomes were assessed with a model that we had described previously. Postoperative outcomes were compared to those of previously reported KTP laser.

RESULTS

Thirty-one subjects (54 VFs treated) underwent blue laser vaporization of VF vascular lesions (average age was 40.63 ± 17.51). Data were compared to those of 66 subjects (100 VFs) who had undergone KTP laser vaporization of VF vascular lesions. There were no significant differences in subject demographics, past medical or surgical history, or preoperative location or severity of vascular lesions. Surgical success for blue laser at the low power densities used was 3.74 ± 0.50, 3.55 ± 0.94, 3.90 ± 0.94, and 3.70 ± 1.11 (out of 5) at postoperative visits 1-4, respectively. Surgical objective score was significantly greater following KTP laser at every postoperative visit. Treatment with KTP laser resulted in significantly greater generalized postoperative edema, and blue laser resulted in significantly greater localized edema at postoperative visits one and two. At visit three and four, there are no significant differences. VF stiffness following blue laser was 2.41 ± 0.67, 1.91 ± 0.69, 1.33 ± 0.47, and 1.10 ± 0.18 (out of 4) at postoperative visits 1-4, respectively. Postoperative VF stiffness did not differ significantly from KTP laser. Postoperative hemorrhage severity after blue laser was 1.79 ± 0.54, 1.59 ± 0.48, 1.15 ± 0.25, and 1.14 ± 0.26 (out of 4) at postoperative visits 1-4, respectively. Blue laser resulted in significantly less VF hemorrhage than KTP laser at the first (1.79 ± 0.54 versus 2.26 ± 0.83) and second (1.59 ± 0.48 versus 1.98 ± 0.72) postoperative visits. Vascular lesions treated with low-power-density blue laser were significantly more likely to recur than those treated with KTP laser (40.74% versus 10.00%). New vascular malformations were significantly more likely to form after blue laser than KTP (24.07% versus 6.00%). Subjects treated with low-power-density blue laser were significantly more likely to undergo repeat surgery than those treated with KTP (31.48% versus 14.00%). Significant predictors for the need for repeat blue laser included lesion recurrence, a lower surgical objective score at the third or fourth postoperative visit and a higher baseline lesion severity grade.

CONCLUSION

Blue laser is an effective tool for the surgical management of VF vascular lesions. Although overall surgical success ratings were inferior to KTP laser at the power densities used, the severity of postoperative edema and VF hemorrhage were significantly less with blue laser. Re-evaluation of blue laser using higher power densities is in progress.

A Double-Anonymised Histopathological Comparative Study of CO2 Laser and Coblation in Head and Neck Surgery

CO2 Laser and Coblation are widely used in Head and neck Surgeries. This study compares the tissue changes produced by these two techniques. 50 Patients who underwent complete excision of benign and malignant pathologies in the Oral Cavity, Oropharynx, and Larynx with Coblation and CO2 Laser were included in the study. The primary excised specimen and another separate specimen from the base of the excised lesion were evaluated histologically based on criteria by Vescovi et al. (1). On histopathological examination, thermal effects (epithelial, connective tissue and vascular) produced by both techniques were comparable. However vascular changes were seen more in tissues CO2 Laser (P = 0.727). Incision margins were more regular in the CO2 Laser group (73%) than in Coblation (55%) but not statistically significant (P = 1.80). Depth of thermal damage (P = 0.171) and connective tissue changes(P = 0.279) was more with Coblation. Both Coblation and CO2 Laser can be used effectively in Head and Neck cases. CO2 Laser, when available, is a better option because of its precise excision, and less collateral tissue damage.

Transoral Laser Microlaryngeal Surgery with MLT Tubes: A Retrospective Case Series

To evaluate effectiveness of using MLT tubes for transoral laser MLS in terms of surgical visualization, complete excision of vocal cord lesions, maintenance of adequate oxygenation and ventilation and the occurrence of any airway related complications. In a retrospective case series study, review of electronic medical records was conducted for 64 patients who underwent transoral laser MLS over an 18-month period. The collected data included vital parameters, mode of ventilation, ET tube details, surgical field of vision, perioperative adverse events and postoperative ventilation requirements. Among the 64 patients, 82.8% of the time, 5 size MLT tubes were used, fixed at mean lengths of 21.6cm in females and 23.07cm in males respectively. A good surgical field of exposure was achieved in 92.2% of patients, with an average FiO2 of 0.29 during laser use and pressure control ventilation mode being the majority choice. 98.4% were extubated on table. The incidence of cuff rupture and bronchospasm was 4.7% and 1.6% respectively with no instances attributable to laser related events. Even though Laser resistant tubes are considered gold standard, MLT tubes can be used by taking adequate precautions to reduce Laser related complications when there is limited availability of laser tubes. Level of evidence Case series.

Investigation of photothermal treatment with 532 nm laser light on laryngeal cancer in an in vivo tumor model

Laryngeal cancer is the second most common cancer in the upper aerodigestive tract, with its incidence increasing across all ages. The conventional treatments for laryngeal cancer include surgical procedure, radiation, and chemotherapy; however, these treatments can lead to various complications. Photothermal therapy (PTT) using laser light has been employed form cancer effective treatment because of its minimal invasion and short operation time. The current study aims to investigate the feasibility of 532 nm PTT on laryngeal cancer in an invivo tumor model. Ex vivo dosimetry evaluation was conducted to determine the laser irradiation conditions, and HEP-2 tumor bearing mice were used to demonstrate in vivo photothermal effects. In addition, histology and western blot analysis were conducted to verify tumor necrosis and any changes in cancer-associated factors in the tumor tissues. The current in vivo results showed that PTT at 5 W for 40 s and 20 W for 10 s had comparable effects in terms of temperature increase and tumor removal. The 532 nm PTT significantly decreased the remaining tumor and downregulated the expression levels of MMP- 9 and ERK. The current study demonstrated that the 532 nm PTT could be a feasible option for treatment of laryngeal tumor with high power delivery for a short exposure time. Further investigations will confirm the endoscopic application of the 532 nm PTT for the treatment of intralaryngeal tissue prior to clinical translation.

Thermal Effects of CO2, KTP, and Blue Lasers with a Flexible Fiber Delivery System on Vocal Folds

OBJECTIVE

To determine the differences in thermal effects on vocal folds between four fiber-routed lasers.

METHODS

In this experimental laboratory study the thermal effects of an AcuPulse Duo CO2 (CO2 AP), UltraPulse Duo CO2 (CO2 UP), KTP, and Blue laser were analyzed using a Schlieren technique on a human tissue mimicking gel model. Power, laser duration, laser fiber distance to tissue and mode (continuous wave [CW] vs pulsed [P] modes) were evaluated in varying combinations in order to compare the effects of the tested lasers and to explore the individual effect on thermal expansion and incision depth of each setting. The model was validated by comparing the results from the Schlieren model with histology of ex vivo fresh human vocal folds after laser irradiation using a selection of the same laser settings, and calculating the intraclass correlation coefficient (ICC).

RESULTS

One thousand ninety-eight Schlieren experiments and 56 vocal cord experiments were conducted. In comparison with CW mode, less thermal expansion occurred in P mode in all lasers, while incisions were deeper in the CO2 and more superficial in the KTP and Blue lasers. The mean thermal expansion was found to be minimally smaller, whereas incision depth was pronouncedly smaller in the KTP and Blue compared to the CO2 lasers. Duration of laser irradiation was the most important factor of influence on thermal expansion and incision depth for all lasers in both CW and P modes. The ICC for consistency between the results of the Schlieren model and the vocal cord histology was classified from fair to excellent, except for the thermal expansion of the Blue laser, which was classified as poor.

CONCLUSION

This study demonstrates important differences in thermal effects between CO2, KTP, and Blue lasers which can be explained by the different physical characteristics of the P modes and divergence of the fiber delivery system. The Schlieren imaging model is a good predictor of the relative thermal effects in vocal fold tissue. Our results can be used as a guidance for ENT surgeons using fiber-routed lasers, in order to achieve effective treatment of vocal fold lesions and prevention of functional impairment of vocal folds.

Strategies for CO2 Laser Use in Laryngeal Microsurgery: A Systematic Review

OBJECTIVE

We aim to systematically review the literature addressing perioperative practices for optimal use of the CO2 laser in laryngeal transoral laser microsurgery (TOLMS), with a focus on safety.

DATA SOURCES

A systematic review of publications indexed in Medline, Embase, and EBM reviews-Cochrane Central Register of Controlled Trials which evaluated perioperative strategies for the use of CO2 laser in laryngeal TOLMS was conducted.

REVIEW METHODS

Records obtained from the search strategy were assessed for eligibility in a 2-step process by 2 independent researchers using the Covidence software.

RESULTS

Among 2143 identified records, 103 were included in this study. The majority of studies (n = 25) focused on the use of the CO2 laser in oncologic resection, while 20 addressed the treatment of vocal cord paralysis, 16 discussed the treatment of pediatric or congenital pathologies, 11 detailed the management of benign lesions, and 31 studies tackled other surgical indications. Strategies for safe CO2 TOLMS were highly heterogeneous across studies and included preoperative measures (ie, related to the environment, staff preparation, patient protection, and ventilation), intraoperative precautions (ie, protection of nontarget structures, technical considerations, topical and systemic medications), and postoperative strategies (ie, related to airway protection, oral intake, vocal rest, hospitalization duration, drug regimen, and consultant follow-up).

CONCLUSION

The results provided in this study can be used as a framework to guide the creation of laser safety protocols across institutions, guide quality improvement initiatives, the development of simulation training activities, and as a tool to facilitate resident teaching and skill assessment.

Five historical innovations that have shaped modern otolaryngological surgery

Throughout history, many innovations have contributed to the development of modern otolaryngological surgery, improving patient outcomes and expanding the range of treatment options available to patients. This article explores five key historical innovations that have shaped modern otolaryngological surgery: Operative Microscope, Hopkins Rigid Endoscope, Laryngeal Nerve monitoring, Cochlear implants and Laser surgery. The selection of innovations for inclusion in this article was meticulously determined through expert consensus and an extensive literature review. We will review the development, impact and significance of each innovation, highlighting their contributions to the field of otolaryngological surgery and their ongoing relevance in contemporary and perioperative practice.

Development of an Improved LASER-Resistant Endotracheal Tube

OBJECTIVES

Surgical fires, particularly within Otolaryngology, remain a surprisingly frequent and devastating complication of laser-related surgery in the oropharynx and airway; Current estimates suggest anywhere from 200 to 600 surgical fires per year in the United States, with 20%-30% of these occurring as a complication of laser surgery and 90%-95% of these occurring in the head and neck region. Unfortunately, the complications of laser surgery in the airway may include respiratory failure, airway burns with stenosis, and may result in mortality. The most commonly utilized endotracheal tube for protection against inadvertent laser strikes, the Laser-Shield II tube (Medtronic), was removed from the commercial marketplace in 2016 after cases of airway fires were reported as a result of feature deficiencies in the product (FDA MAUDE Database review). Since the demise of the Laser-Shield II tube, alternatives such as the Mallinckrodt laser tube and handmade reinforced tubes have been utilized, although shortcomings in design and features have made these options less appealing to practicing Otolaryngologists. Creating a laser-safe endotracheal tube is critical for safe upper airway surgery. This paper evaluates new technologies, materials, and technical innovations in endotracheal tubes that may advance patient safety in laser-assisted Otolaryngology procedures.

STUDY TYPE

This paper evaluates new technologies, materials, and technical innovations in endotracheal tubes that may advance patient safety in laser-assisted Otolaryngology procedures.

METHODS

First, this article reviews the background of laser surgery in Otolaryngology and the consequent risk of surgical fire with resultant development of laser-resistant endotracheal tubes and commercial availability. Next, a review of claims and national database review of product failures related to previous laser-resistant endotracheal tubes is performed through the FDA MAUDE database. This includes an evaluation of cases: review of techniques in laser airway surgery including spontaneous ventilation, decreased O2 concentration, currently available endotracheal tubes including "handmade" fixes for perceived safety risks, and determination of failure points for previous laser-resistant endotracheal tubes. Third, the paper reviews the requested features of an "ideal" laser-resistant endotracheal tube. Finally, the paper reviews failure testing from an initial, unsuccessful attempt at material development and the consequent development of alternative technologies that address failure points from previous endotracheal tubes and addresses requested features with a detailed analysis of FDA-approval required testing. Extensive lab testing of the new tube predicts a significant reduction of risk in vivo with inability to perforate the shaft or cuff of the tubes under standard working conditions.

RESULTS

While no iteration of a laser-resistant endotracheal tube is entirely laser safe, advances in technology can improve the safety profile of these devices. The new tube contains a double cuff, a soft and flexible shaft to minimize laryngeal insertion trauma, a smooth external surface, a tight-to-shaft balloon, and methylene blue dye in the cuff to alert the user to inadvertent penetration. These characteristics were the most requested by laryngologists in the development of a new laser-resistant tube. The newest endotracheal tube brings the features most requested by Otolaryngologists in a laser-resistant tube, and improves the safety profile over previous tubes.

CONCLUSION

Development of a new endotracheal tube represents an advancement in safety for the Otolaryngologist in laser airway surgery. Understanding the previous history and the science behind surgical fire formation is essential in advancing safety for patients in the future.

LEVEL OF EVIDENCE

N/A Laryngoscope, 134:S1-S12, 2024.

Performance analysis of a liquid lens for laser ablation using OCT imaging

Laser ablation has been used in different surgical procedures to perform precise treatments. Compared with previous free-beam laser delivery systems, flexible-optical-fiber-based systems can deliver laser energy to a curved space, avoiding the requirement of a straight working path to the target. However, the fiber tip maintains direct contact with the tissue to prevent laser divergence, resulting in fiber damage, uneven ablation, and tissue carbonization. Here, a liquid lens is used to address the problem of laser defocusing when radiating targets at different depths for flexible-optical-fiber-based systems. The liquid lens focuses a laser with a maximum power of 3 W onto a medium-density fiberboard at a focal length of 40-180 mm. The relationships between the ablation crater diameter and depth with the radiation time and laser power have been quantitatively evaluated through OCT (optical coherence tomography) imaging. Experiments demonstrate that the liquid lens can continuously focus the high-power laser to different depths, with the advantages of compact size, fast response, light weight, and easy operation. This study explores liquid-lens-based focused laser ablation, which can potentially improve the performance of future medical image-guided laser ablation.

Correlation Between the Effects of CO2 Laser and Histopathological Analysis in Vocal Cord Lesions: An Observational Study

Lasers are based on the principle of light amplification by empowering atoms to store and emit light in a coherent form. Through their effect on tissues, lasers reduce hemorrhage allowing the surgeon to work in a clear field with precise removal of the tissues. Irradiation of the soft tissues by lasers produces thermal effects on the surrounding healthy tissues which can make histopathological examination difficult. Hence this study was done to find a correlation between adjustable parameters of CO2 laser and the extent of collateral thermal damage in the excised vocal cord lesions on histopathological examination and diagnosis. In this study, we enrolled 80 patients who were divided into 4 groups with different combinations of laser power and mode, used during transoral laser micro laryngeal surgery for the excision of vocal cord lesions and subsequent histopathological analysis to objectively measure the extent of thermal damage zone and subjectively assess histo-morphological effects of thermal damage in terms of grade of carbonization. The extent of the thermal damage zone is directly related to the power of the laser, but the mode of the laser had no relation with the thermal damage zone in our study. On subjective histo-morphological examination of excised lesions showed that both power and mode of laser have significant effects on tissue morphology. Continuous mode causes a significantly higher grade of carbonization as compared to the superpulsed mode of the laser. However, in our study it was seen that charring in no way affected the diagnosis in any of the biopsies examined whatever the power or mode of the laser used. The depth and width of the tissue thermal damage zone are mainly dependent upon the laser parameters (power and mode). Although considering the limitations of this study carried out in terms of sample size, it would be pertinent to mention here that further studies with larger cohorts need to be done to authenticate these results.

A Case Report of Juvenile-Onset Recurrent Respiratory Papillomatosis

The most common benign laryngeal neoplasm in children is a papilloma. Laryngeal papillomatosis is a chronic disease and is rare in children. We report the case of a four-year-old Malay girl in whom chronic laryngeal papillomatosis, most likely acquired vertically during labor, was detected. She presented with hoarseness of voice for three years, and a flexible laryngoscopy examination revealed features of papilloma in the glottis area. The patient underwent direct laryngoscopy followed by excision of mass using the cold instrument. Surgical intervention is the primary treatment modality for laryngeal papillomatosis to maintain airway patency and voice quality.

Recent updates in laryngeal hemangioma management: a scoping review

PURPOSE

To provide a comprehensive review of the current strategies in the management of laryngeal hemangiomas, with an aim to introduce a management algorithm that aligns with the variable clinical presentations and anatomical complexities of these lesions.

METHODS

We conducted an extensive literature search across major databases using specific and general terms, combined with Boolean operators, to ensure comprehensiveness. Articles from January 2004 to August 2023 were included, with findings categorized by management approach.

RESULTS

Laryngeal hemangiomas exhibit a spectrum of manifestations, ranging from asymptomatic lesions to those causing severe airway obstruction. Optimal management demands an individualized approach tailored to the patient's unique presentation and anatomical considerations. Diverse treatment modalities, each with distinct indications, advantages, and limitations, are explored. Notable highlights encompass the prominent role of Beta-blockers, notably Propranolol, in addressing problematic infantile hemangiomas, the nuanced efficacy of laser therapies contingent upon hemangioma type and depth, and the critical relevance of tracheotomy in emergencies. Novel approaches like transoral robotic surgery and transoral ultrasonic surgery, demonstrate promise in specific scenarios. We propose a management algorithm based on the complexity and presentation of laryngeal hemangiomas, emphasizing individualized treatment strategies, thereby addressing the unique challenges and nuances of each case.

CONCLUSION

Laryngeal hemangioma management requires personalized approaches informed by diverse therapies, clinical expertise, and collaboration. The review introduces an algorithm spanning observation to advanced interventions, adapting to each case's complexity. Ongoing research promises innovative treatments.

Bessel light beam for a surgical laser focusing telescope-a novel approach

As the demand for CO[Formula: see text] laser surgeries continues to grow, the quality of their main instrument, the laser micromanipulator, becomes increasingly important. However, in many surgery systems, a large ratio of the laser power is wasted due to the reflection from the mirror of a telescopic system, like a Cassegrain telescope, back to the laser side, which not only decreases the system's efficiency but can also damage the system itself. In this article, we introduce a new design of the micromanipulator telescope for CO[Formula: see text] laser surgery, which employs a Bessel beam to improve the system efficiency. As in the propagation of a Bessel beam, the power of the light beam can be transferred from the center to a ring shape, the whole power reflected from the first mirror can reach the second mirror and no power goes back to the second mirror hole. The micromanipulator telescope design and optimization are carried out using Zemax Optics Studio, and the integration of the Bessel beam into the system is implemented using MATLAB. Our simulation results show that by applying the appropriate Bessel beam, the system efficiency can reach more than 96%, and the normalized peak irradiance can increase by 40 to 73% for various working distances. In addition to increasing the system efficiency and normalized peak irradiance, resulting in a sharper surgical blade, the use of the Bessel beam enhances the depth of focus, making the system less sensitive to depth misalignment.

Treatment efficacy of 532-nm diode laser glottoplasty in patients with sulcus vocalis: a prospective study

PURPOSE

This study prospectively assessed the efficacy and safety of 532-nm diode laser glottoplasty in patients with sulcus vocalis.

METHODS

A prospective human trial was performed from August 2016 to September 2021. 532-nm diode laser glottoplasty was performed in 30 consecutive patients with sulcus vocalis who suffered from voice problems. Patients underwent acoustic aerodynamic, perceptual, stroboscopic, and Voice Handicap Index-10 (VHI-10) evaluations before and 1, 6, and 12 months after laser glottoplasty.

RESULTS

Most subjective parameters showed significant improvement (P < 0.05) at 6 months after laser glottoplasty and remained stable at 12 months. Most objective parameters showed significant improvement (P < 0.05) at 12 months after laser glottoplasty. Complications during follow-up included mild vocal fold vibration reduction in 3.3% of patients (1/30) and persistent vocal fold edema in 3.3% of patients (1/30).

CONCLUSIONS

Statistically significant voice improvement at 12 months after 532-nm diode laser glottoplasty was achieved without serious complications.

The Safety and Efficacy of the 445-nm Blue Laser for Operative Management of Benign Nonvascular Laryngeal Lesions

The 445-nm blue laser combines the features of photocoagulative vascular lasers and cutting lasers in one device. The purpose of the present study was to evaluate the safety and efficacy of the 445-nm blue laser for the treatment of benign laryngeal pathologies, other than vascular lesions. Outcomes were compared to those when already-established therapies were used.

METHODS

Adult voice center patients who underwent surgical intervention for vocal fold (VF) mass, VF scar, laryngeal stenosis, laryngeal web, or Reinke's edema were included in this retrospective study. Outcomes were compared to those achieved when traditional treatment modalities were used, including cold steel, CO2 laser, potassium-titanyl-phosphate (KTP) laser, and coblator. Strobovideolaryngoscopy footage was evaluated using a previously described model at four time points: postoperative visit #1: 1-14 days, postoperative visit #2: 30-60 days, postoperative visit #3: 61-365 days, postoperative visit #4: >365 days.

RESULTS

Eighty cases using the blue laser and 153 controls (n = 78 cold steel, n = 51 KTP laser, n = 22 CO2 laser, n = 2 coblator) were included in this study. Procedures performed using blue laser included VF mass excision (n = 45), VF scar reduction (n = 16), laryngeal stenosis resection/repair (n = 25), laryngeal web excision (n = 7), and reduction of Reinke's edema (n = 1). On postoperative strobovideolaryngoscopy examination, the surgical objective score did not differ significantly between the blue laser cohort and all controls at any postoperative visit. VF edema did not differ significantly between the blue laser cohort and all controls at any postoperative visit. VF hemorrhage scores were significantly lower in the blue laser cohort compared to all controls at the first postoperative visit, but hemorrhage had resolved almost entirely by the second postoperative visit in all groups. Postoperative VF stiffness was worse in the blue laser group at the third postoperative visit compared to controls, but both groups had improved to similar levels by the fourth postoperative visit. The rate of lesion recurrence (24.29% versus 17.19%) did not differ significantly between the blue laser cohort and controls on multivariate analysis (Odds ratio [OR] = 1.081 [0.461-2.536]). The complication rate (12.50% versus 10.46%) did not differ significantly between the blue laser cohort and all controls on multivariate analysis (OR = 0.992 [0.375-2.624]). The blue laser was associated with a lower rate of revision surgery (30.00% versus 34.64%) on multivariate analysis (OR = 0.380 [0.168-0.859]).

CONCLUSION

The 445-nm blue laser is safe and effective for the management of benign laryngeal lesions. It has efficacy and safety similar to those of traditional treatment modalities (including cold steel, CO2 laser, and KTP laser). Use of the blue laser may lead to lower rates of early postoperative hemorrhage and revision surgery. No adverse effects attributed directly to the use of the blue laser were observed in this study. Further research is encouraged to confirm or refute these findings.

Office-based Blue Laser Therapy of Vocal Fold Polyps: A Cohort of 18 Patients: Blue Laser Therapy of Vocal Fold Polyps

OBJECTIVE

To investigate the effect of office-based blue laser therapy of vocal fold polyps on voice.

METHODS

The medical records and video recordings of patients who underwent office-based laser therapy in a tertiary referral center between February 2020 and May 2020, and May 2021 and October 2022 was conducted. Only patients with vocal fold polyps who had undergone office-based blue laser therapy were included. The voice was evaluated before and after surgery using the Voice Handicap Index-10 (VHI-10), GRB perceptual evaluation, acoustic analysis, and maximum phonation time.

RESULTS

A total of 18 patients were included. The mean age of the study group was 52.5 ± 11.94 years. The male-to-female ratio was 2:1. Ten patients of the total group (53.6%) had hemorrhagic polyps and the most common site was the mid-third of the vocal fold. All patients who presented for follow-up (n = 15) had partial or complete regression of the lesion (4 and 11, respectively). There was a significant decrease in the mean score of VHI-10 (17.6 ± 9.97 vs. 4.27 ± 5.76, p < 0.001) and in the means of grade of dysphonia (2.0 ± 0.73 to 0.5 ± 0.63, p < 0.001), roughness (1.88 ± 0.81 to 0.44 ± 0.51, p < 0.001) and breathiness (0.81 ± 0.75 to 0.13 ± 0.34 p < 0.001). There was also a marked decrease in the perturbation parameters (jitter and shimmer) and a significant increase in the MPT from 10.66 ± 4.22 s to 14.26 ± 6.26 s (p = 0.028).

CONCLUSION

Office-based blue laser therapy is an effective treatment modality in patients with vocal fold polyps.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2712-2718, 2023.

Indications, Efficacy, Safety, and Clinical Outcomes of 585 nm Pulsed Dye Laser in Non-Malignant Laryngeal Lesions: A Systematic Review

The objective of this manuscript was to review the indications, efficacy, and safety of a 585 nm pulsed dye laser (PDL) in non-malignant laryngeal lesions. Following the PRISMA statement recommendations, three independent authors searched for articles published in PubMed/MEDLINE, the Cochrane Library, Google Scholar, Scielo, and Web of Science. A bias analysis was performed following NICE guidance tools. From the 506 identified publications, 19 observational studies met the inclusion criteria. The PDL improves vocal quality objectively and subjectively in vascular lesions (p < 0.005) and improves vocal quality in patients with dysplasia/leukoplasia without changing the natural history of the disease compared to other treatments. Reinke's edema and granulomas require an average of 1.5 PDL sessions for resolution. Treatment of recurrent respiratory papillomatosis requires multiple sessions, with complete remission achieved in 50-70% of patients. Regardless of the lesion, the tolerance of the procedure under local anesthesia is exceptional (84-97%), and the results in terms of regression and vocal quality are promising. The complication rate is minimal, and the procedure does not interfere with other treatment alternatives. There is no consensus on laser settings. The lack of consistent use in evaluating vocal outcomes, whether objective or subjective, prevents the comparability between studies. The 585 nm pulsed dye laser appears to be an effective and safe therapeutic option in patients with non-malignant laryngeal pathology. Future controlled studies are needed to compare the 585 nm pulsed dye laser with other lasers or cold instrument procedures.

Surgical Outcome of Potassium-Titanyl-Phosphate (KTP) Laser Photocoagulation for Vocal Fold Vascular Lesions

INTRODUCTION

Laser technology is used in microscopic direct laryngeal surgery for a variety of indications. Lasers are categorized broadly as photoangiolytic or cutting/ablating lasers, based on the chromophores that absorb their energy. Photoangiolytic lasers such as the 532 nm Potassium-Titanyl-Phosphate (KTP) laser are absorbed selectively by the chromophore hemoglobin, facilitating controlled intravascular coagulation, with preservation of the overlying epithelium and adjacent tissue. Efficacy of the KTP laser has been demonstrated for incision, coagulation, and ablation in vocal fold (VF) surgery.

OBJECTIVE

The purpose of the present study was to examine surgical outcomes following KTP laser photocoagulation for the management of VF vascular lesions.

METHODS

Adult patients with sufficient data who had undergone KTP laser photocoagulation in the operating room for the treatment of VF vascular lesions were included in this retrospective study. Strobovideolaryngoscopy (SVL) video footage from all preoperative visits and all available postoperative visits was compiled and de-identified. Patients were followed up at days 1-7, 8-14, 30-60, and greater than 60 days after surgery. Three blinded physician evaluators reviewed and evaluated the SVL footage independently for postoperative outcome parameters. Postoperative SVL video footage was evaluated on a 5-point scale for surgical success (surgical objective score; 1 = failure and 5 = complete success). The average surgical objective score was 4.36, 4.04, 4.25, and 4.46 (out of 5) at postoperative visits 1-4, respectively.

RESULTS

There were 60 cases (19 male and 41 female) included in the retrospective cohort. The average age was 42.42 ± 15.51 (range = 18-74). Fifty-one-point six seven percent of subjects were professional voice users (singers, teachers, public speakers, and others). All subjects were diagnosed preoperatively with VF vascular malformations and had undergone pulsed KTP laser photocoagulation. There were 40 bilateral cases and 20 unilateral cases, for a total of 100 VFs included in the study. Vascular malformation recurrence was identified in 3.00% and 10.00% of subjects at the third and fourth postoperative visits, retrospectively. The formation of new vascular malformations was identified in 0.00%, 1.00%, 6.00%, and 7.00% of subjects at postoperative visits 1-4, respectively.

CONCLUSION

KTP laser photocoagulation is highly effective for the management of vocal fold vascular lesions. Presence of hemorrhage or edema does not affect the long-term surgical outcome. In relatively few cases, vascular lesion recurrence or formation of new vascular lesions may occur.

Reinke's Edema: Cold Steel Versus Radiofrequency Coblation

OBJECTIVE

This study compared the effects of radiofrequency (RF) coblation and cold steel (CS) surgery for the treatment of Reinke's edema (RE).

METHODS

A retrospective analysis was conducted on 61 patients with RE, with 33 (54.1%) in the CS surgery group and 28 (45.9%) in the RF coblation group. The primary endpoints were the bilateral operation time and dyspnea severity, assessed preoperatively and at 1 and 3 months postoperatively. Secondary endpoints included subjective and objective vocal assessments, laryngovideostroboscopy (LVS) images, and Voice Handicap Index-10 (VHI-10) scores obtained before and at 1 and 3 months postoperatively.

RESULTS

The average bilateral operation time was significantly shorter in the RF coblation group (24.2 ± 3.9 min) compared to the CS group (38.4 ± 5.2 min) (P = .041). All patients experienced a decrease in their Dyspnea Severity Index (DSI) scores postoperatively, with no significant differences observed between the two groups at any time point. However, improvements in the grade of hoarseness, roughness, and asthenia were significantly greater in the RF coblation group than in the CS group (P < .001). There were no statistically significant differences in breathiness and strain between the two groups. The average VHI-10 score significantly decreased from preoperative values in both groups (P < .001), with no significant differences observed between the two groups at any time point.

CONCLUSIONS

The RF coblation procedure is a reliable and safe method for RE surgery, offering an effective treatment choice for RE.

Transoral Flexible Laser Surgery of the Larynx with Blue Laser

INTRODUCTION

Laser surgery of the larynx is currently the standard of clinical practice in a multitude of procedures. Lasers with photoangiolytic properties have a wide application in endolaryngeal lesions. One of their most prominent features is the ability to coagulate blood vessels, reducing unwanted tissue damage. Our objective is to expose the uses of the blue laser (445 nm) in the larynx.

MATERIAL AND METHODS

A retrospective study was carried out including 47 patients treated with blue photoangiolytic laser from October 2021 to January 2023 at a university hospital. Demographic data, type of lesion presented, date of intervention and scope of the procedure, as well as the parameters of the laser used, were recorded. The number of sessions received per patient, the result and complications were also collected.

RESULTS

A total of 47 patients with laryngeal lesions were treated, including vascular angiomas, laryngeal sulcus vocali, vocal cord polyps, Reinke's edemas, laryngeal papillomatoses, subglottic stenosis, laryngeal synechiae, subglottic granulomas, glottic scars, vocal fold leukoplakias, laryngeal dysplasias and tracheostomal granulomas. The mean age was 52.5 years, and 64.3% of the patients were women. The range of power used in the resective surgeries was 2-10 Watts with a 20-millisecond window. The average number of sessions received was 2.1 (range 1-4). A satisfactory situation was obtained in 45 of the 47 patients treated (95.75%), and an evident decrease in lesions was seen in the remaining two. There was no evidence of any complications directly derived from the use of the blue laser. Twenty-seven cases (54%) were treated exclusively in-office.

CONCLUSIONS

The blue laser is safe and effective in the treatment of a wide range of laryngeal pathologies. Its advantages include its portability, its photoangiolytic qualities as well as its ability to vaporize tissue in contact mode, which can treat subepithelial vessels or resect lesions.

Gold Nanoparticles Functionalized with 2-Thiouracil for Antiproliferative and Photothermal Therapies in Breast Cancer Cells

Nanoparticles have been used to transport drugs to various body parts to treat cancer. Our interest is in gold nanoparticles (AuNPs) since they have the capacity to absorb light and convert it to heat, inducing cellular damage. This property is known as photothermal therapy (PTT) and has been studied in cancer treatment. In the present study, biocompatible citrate-reduced AuNPs were functionalized with a biologically active compound, 2-thiouracil (2-TU), of potential anticancer activity. Both the unfunctionalized (AuNPs) and functionalized (2-TU-AuNPs) were purified and characterized by UV-Vis absorption spectrophotometry, Zeta potential, and Transmission Electron Microscopy. Results showed monodispersed, spherical AuNPs with a mean core diameter of 20 ± 2 nm, a surface charge of -38 ± 5 mV, and a localized surface plasmon resonance peak at 520 nm. As a result of functionalization, the mean core diameter of 2-TU-AuNPs increased to 24 ± 4 nm, and the surface charge increased to -14 ± 1 mV. The functionalization of AuNPs and the load efficiency were further established through Raman spectroscopy and UV-Vis absorption spectrophotometry. The antiproliferative activities of AuNPs, 2-TU and 2-TU-AuNPs were examined by a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay in the MDA-MB-231 breast cancer cell line. It was established that AuNPs significantly enhanced the antiproliferative activity of 2-TU. Furthermore, the irradiation of the samples with visible light at 520 nm decreased the half-maximal inhibitory concentration by a factor of 2. Thus, the 2-TU drug concentration and its side effect during treatments could be significantly reduced by synergistically exploiting the antiproliferative activity of 2-TU loaded onto AuNPs and the PTT effect of AuNPs.

Transoral flexible laser surgery of the upper aerodigestive tract with blue laser

PURPOSE

The introduction of fiber-guided lasers was a breakthrough in laryngology practice, opening the path for treating different pathologies with minimally invasive procedures, both in the operating room and in the office. The most recent technology in the area is the blue laser, which combines photoangiolytic and cutting properties, characteristics that make this equipment suitable for its use in upper aerodigestive tract surgery. However, there is not enough experience in this area. The authors present a case series of patients with different pharyngeal, laryngeal, and tracheal pathologies who were treated by means of transoral procedures using fiber-guided blue laser.

METHODS

The surgical records of patients with different upper aerodigestive tract pathologies who were treated with fiber-guided blue laser in the operating room, under general anesthesia with jet ventilation or supraglottic ventilation using suspension laryngotracheoscopy techniques between February 2018 and March 2022 were reviewed.

RESULTS

A total of 80 surgical interventions in a group of 38 patients were performed. A wide variety of procedures was executed, either using the laser alone or in combination with other techniques to treat different pathologies of the aero-digestive tract safely and effectively, with adequate functional results.

CONCLUSIONS

Following all necessary precautions, blue laser is a reliable tool to perform minimally invasive surgeries in the operating room using TOFLS techniques. It can be used alone or in combination with other devices to achieve the desired goals.

Surgery and Adjuvant Therapy Improve Derkay Scores in Adult and Pediatric Respiratory Papillomatosis

OBJECTIVES/HYPOTHESIS

Comparing Derkay anatomical score at time of procedure, disease characteristics, and mean treatment interval among adult and pediatric patients with recurrent respiratory papillomatosis (RRP).

STUDY DESIGN

Restrospective study.

METHODS

Retrospective review of juvenile-onset (JO) and adult-onset (AO) RRP patients treated longitudinally at pediatric and adult institutions from 1999 to 2019. Patients were included if they had a tissue diagnosis of papilloma and had at least a 12-month follow-up.

RESULTS

One hundred and twelve patients met inclusion criteria (68 JO-RRP and 44 AO-RRP). All patients were stratified into either potassium titanyl phosphate (KTP) (n = 42), CO₂ (n = 21), or microdebrider (n = 49) treatment groups. The Derkay score improved between first and last procedure in the KTP group (mean difference, 3.5; P < .001), CO₂ group (mean difference, 4.4; P < .001), and microdebrider group (mean difference, 4.1; P < .001), but overall improvement did not differ across groups (P = .73). Baseline mean to last mean Derkay score improved for nine patients during bevacizumab treatments (mean difference, 3.0; P = .01) but did not improve for these same patients during an interval prior to receiving bevacizumab treatments. Baseline mean to last mean Derkay score improved for 19 patients during cidofovir treatments (mean difference, 3.84; P < .001) but did not improve for these same patients during the interval prior to receiving cidofovir treatments. The AO-RRP population had more patients with dysplasia (50%) compared to JO-RRP population (10%) (P < .001).

CONCLUSION

Various surgical modalities appear to be equally effective treatments for RRP. Adult and pediatric patients have decreased recurrent disease burden when receiving bevacizumab or cidofovir. AO-RRP patients have more concomitant dysplasia.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:2420-2426, 2022.

Systematic review of the use of human papillomavirus vaccine as adjuvant therapy for juvenile-onset recurrent respiratory papillomatosis

INTRODUCTION

Juvenile-onset RRP (JoRRP) is considered a rare disease with high morbidity and healthcare costs. The management of RRP has received much scientific attention in recent years and several treatment methodologies have been explored, including therapeutic use of HPV vaccine. There has been increasing interest in the off-label use of the vaccine in virus-induced disease processes such as RRP, due to its immunomodulatory effect and activating role on the innate and adaptive immune system. This review explores the efficacy of the HPV vaccination as a therapeutic tool in the pediatric population.

METHODS

The review of the English literature included three electronic databases, PubMed, SCOPUS, and Cochrane, without publication date restrictions. Studies and reports identified by the database search were reviewed and assessed by two independent reviewers.

RESULTS

The literature searches identified 768 unique citations, from which 204 duplicates were removed (n = 564). A total of 547 articles were excluded as they did not meet our inclusion criteria. A total of 12 studies (3 experimental studies, 3 case series, 6 case reports) that met the inclusion criteria and reported one or more of the outcomes of interest were included for our review. The assessment of the outcome measures evaluated (number of surgeries during the follow-up period, ISI, SPM, Derkay or severity scores, and remission status) revealed that eight out of 12 studies included in the review showed varying degrees of potential benefits from the administration of the vaccine as a treatment modality compared to surgical interventions and/or concurrent adjuvant therapies alone.

CONCLUSION

We conclude that while the therapeutic use of HPV vaccination has shown promise for some JoRRP patients, it overall remains uncertain with the currently available data. There is a need for a prospective multi-centric trial with a larger sample size to fully characterize the potential use of the vaccine in the management of JoRRP.

A Study on Comparison of Conventional Micro Laryngeal Micro Dissection Surgery with Carbon Dioxide Laser in Management of Benign Lesions of Larynx

Dysphonia is a common symptom in benign and pre malignant lesions of larynx affecting vocal cords. Surgical excision is the main stay of treatment. Only a limited number of studies have compared the efficacy of microdissection versus CO2 laser surgery in the larynx. In the present study we have compared conventional micro-laryngeal surgery and carbon dioxide laser assisted microsurgical technique in the management of these lesions. A randomized prospective study was conducted in 88 cases of benign and pre malignant lesions affecting vocal cords were divided randomly to undergo surgery either by conventional micro dissection or CO2 laser assisted techniques in a tertiary care hospital. The groups were assessed through vocal cord morphological observation by videostroboscopy and subjective voice assessment parameters GRBAS score and VHI10 index preoperatively and 2 weeks and 3 months postoperatively by a panel of blinded viewers and listeners. Surgical and recovery times were compared between the two groups. Intraoperative blood loss was compared by gauze visual analogue. Patients recovered remarkably well following both the techniques as denoted by the voice parameters. Peroperative bleeding was observed to be significantly reduced in the laser excision group; operating time was significantly increased in this group. Duration of hospital stay was similar in both groups. No differences in clinical outcomes are identified when comparing microdissection with laser excision of benign lesions.

Surgical management of laryngeal bilateral abductor palsy: comparative study between carbon dioxide and diode lasers

This study aims to compare the results of both CO₂ laser and diode laser combined arytenoidectomy with posterior cordectomy in managing patients with bilateral vocal fold paralysis. A prospective study involved 80 bilateral vocal cord immobility patients in adduction. They are divided into two groups according to the laser used, whether CO₂ (with a wavelength of 10.6 µm) or diode (with a wavelength of 980 nm). We used mMRC (Modified Medical Research Council) dyspnea scale to assess dyspnea in our patients, while the voice was evaluated by both maximum phonation time and the voice handicap index. Quantitative variables were described using means and standard deviations, while categorical variables were described using frequencies and were compared using the chi-square test, Fisher exact test, and Monte Carlo test. There was a statistically non-significant difference between the studied groups regarding mMRC dyspnea scale and Voice Handicap Index preoperatively and postoperatively. There is a statistically significant difference between the two groups regarding maximum phonation time postoperatively (significantly higher in the CO₂ laser group) (p < 0.001). The CO₂ laser and diode laser could be used safely for the management of bilateral vocal cord paralysis. The CO₂ laser maintains better voice parameters and less postoperative pain, while the diode laser gives less operative time, lower cost, and simplicity of use.

Risk of airway fire with the use of KTP laser and high flow humidified oxygen delivery in a laryngeal surgery model

Airway surgery presents a unique environment for operating room fire to occur. This study aims to explore the factors of combustion when using KTP laser with high flow oxygen in an ex-vivo model. The variables tested were varying tissue type, tissue condition, oxygen concentration, laser setting, and smoke evacuation in a stainless-steel model. Outcome measures were time of lasing to the first spark and/or flame. A multivariate Cox proportional hazard model was used to determine the risk of spark and flame across the different risk factors. For every 10% increase in oxygen concentration above 60% the risk of flame increased by a factor of 2.3. Continuous laser setting at 2.6 W increased the risk by a factor of 72.8. The risk of lasing adipose tissue is 7.3 times higher than that of muscle. Charred tissue increases the risk of flame by a factor of 92.8. Flame occurred without a preceding spark 93.6% of the time. Using KTP laser in the pulsed mode with low wattages, minimising lasing time, reducing the oxygen concentration and avoiding lasing adipose or charred tissue produce a relatively low estimated risk of spark or flame.

Multifunctional Gold Nanoparticles for Improved Diagnostic and Therapeutic Applications: A Review

The medical properties of metals have been explored for centuries in traditional medicine for the treatment of infections and diseases and still practiced to date. Platinum-based drugs are the first class of metal-based drugs to be clinically used as anticancer agents following the approval of cisplatin by the United States Food and Drug Administration (FDA) over 40 years ago. Since then, more metals with health benefits have been approved for clinical trials. Interestingly, when these metals are reduced to metallic nanoparticles, they displayed unique and novel properties that were superior to their bulk counterparts. Gold nanoparticles (AuNPs) are among the FDA-approved metallic nanoparticles and have shown great promise in a variety of roles in medicine. They were used as drug delivery, photothermal (PT), contrast, therapeutic, radiosensitizing, and gene transfection agents. Their biomedical applications are reviewed herein, covering their potential use in disease diagnosis and therapy. Some of the AuNP-based systems that are approved for clinical trials are also discussed, as well as the potential health threats of AuNPs and some strategies that can be used to improve their biocompatibility. The reviewed studies offer proof of principle that AuNP-based systems could potentially be used alone or in combination with the conventional systems to improve their efficacy.

Management of bilateral abductor paralysis: posterior cordectomy with partial arytenoidectomy using diode laser

PURPOSE

This study aims to assess the role of diode laser-assisted posterior cordectomy with partial arytenoidectomy in the management of bilateral vocal fold paralysis patients.

METHODS

Posterior cordectomy with partial arytenoidectomy using diode laser was performed to thirty-nine patients with bilateral vocal fold paralysis. Voice was evaluated by maximal phonation time and Arabic version of the voice handicap index, while breathing difficulty was assessed by mMRC (Modified Medical Research Council) dyspnea scale.

RESULTS

There is a statistically significant decrease in mMRC from 2.8 ± 0.645 preoperatively to 0.84 ± 0.554 postoperatively (p < 0.001). However, maximum phonation time is significantly decreased from 8.04 ± 0.978 preoperatively to 6.92 ± 0.997 postoperatively (p < 0.001); there is a statistically non-significant increase in vocal handicap index from 37.12 ± 6.26 preoperatively to 37.24 ± 6.22) postoperatively (p > 0.05).

CONCLUSIONS

The diode laser is a viable method that should be considered for the management of bilateral vocal cord paralysis. It seems to be a very promising laser device, so we expect that new diode laser wavelengths (980 nm) will continue to emerge, making it a good alternative to the CO₂ laser, but with lower cost, accurate manipulation, portability, shorter duration, and simplicity of use.

LEVEL OF EVIDENCE

4.

Applications of Office-Based 445 nm Blue Laser Transnasal Flexible Laser Surgery: A Case Series and Review of Practice

BACKGROUND

The recent introduction of 445 nm blue laser to office-based laryngology presents potential advantages. These include a desirable combination of cutting and photoangiolytic qualities and a lightweight, shock-resistant design. Despite its increasing use, current evidence is limited to experimental data and case reports.

OBJECTIVES

The authors present a case series and overview of office blue laser transnasal flexible laser surgery (TNFLS), considering indications, patient selection, safety, technique, and surgical outcomes. We also review the safety and relevance of TNFLS to the ongoing coronavirus pandemic.

METHODS

Retrospective case series and narrative review. Our primary outcome measure was preoperative and postoperative Voice Handicap Index (VHI-10) score. Complications were documented by nature and severity.

RESULTS

Thirty-six cases of office blue laser TNFLS were performed. A statistically significant improvement in VHI-10 score was demonstrated in cases of recurrent respiratory papillomatosis (RRP) and benign laryngeal lesions causing dysphonia (P < 0.01 and 0.045). Blue laser also proved effective in assisting office biopsy procedures. A minor and self-limiting complication was reported.

CONCLUSIONS

Office blue laser TNFLS is safe and effective in the treatment of RRP and a range of benign laryngeal lesions. Future research should compare the efficacy and safety of blue laser with potassium titanyl phosphate laser in office-based treatment of these conditions. Further assessment of the cutting qualities of blue laser, initially in the theater environment, is necessary to refine our understanding of future applications.

Lasers in Οtolaryngology: A Laser Odyssey From Carbon Dioxide to True Blue

In this special issue of the Ear Nose and Throat (ENT) journal entitled Lasers in Otolaryngology, we attempted to cover and accommodate different experiences from around the globe on both established and some not so well-known techniques and indications for Lasers in most ENT subspecialties. Despite the COVID 19 pandemic, authors from all over the world have expressed their interest in publishing their Laser experiences with ENT journal and for this we are very grateful.

Reinke's edema: a proposal for a classification based on morphological characteristics

PURPOSE

Reinke's edema is a benign laryngeal condition characterized by swelling of the superficial layer of the lamina propria of the vocal fold. The aim of this work is to propose a new classification of Reinke's edema based on its morphological characteristics.

METHODS

Our classification is a synthesis of the classifications available in the literature and is based on morphological characteristics such as the involvement of one or two vocal folds and the presence or absence of polypoid lesions regardless of the observation method.

RESULTS

We indicate four types of Reinke's edema: type 1: Reinke's edema of one vocal fold; type 2: Reinke's edema of both vocal folds; type 3: Reinke's edema of one vocal fold with associated polypoid lesion, not necessarily the same fold of the edema; type 4: Reinke's edema of both vocal folds with associated polypoid lesion on one or both folds.

CONCLUSION

Our proposed classification for Reinke's edema represents a synthesis of the classifications available in the literature and is characterized by a simple categorization based on morphological characteristics commonly visible through laryngoscopy.

Comparative Study Between Conventional Microlaryngeal Surgery and Carbon Dioxide Laser in Management of Minimal Associated Pathological Lesions of Vocal Folds

The aim of this study is to compare the relatively new CO₂ laser microlaryngeal surgery and conventional cold dissection method in treatment of minimal associated pathological lesions of vocal folds. Eighty patients aged 20-70 years old were randomly divided into two groups, group A (40 patients) was treated by the conventional method and group B (40 patients) was treated with CO₂ laser microlaryngeal surgery. Assessment procedures included GRBAS scale, stroboscopic examination, and Arabic version of voice handicap index. Results stated that improvement of quality of voice after surgery in both techniques had no significant difference. The significant difference was in operative time and bleeding because laser had less time and bleeding. Both techniques had no recurrence within 3-months follow-up.

Optimizing Settings for Office-Based Endoscopic CO2 Laser Surgery Using an Experimental Vocal Cord Model

OBJECTIVES/HYPOTHESIS

To provide insight in the thermal effects of individual laser settings in target tissues to optimize flexible endoscopic CO₂ laser surgery treatment.

STUDY DESIGN

Experimental laboratory study.

METHODS

Thermal effects of the CO₂ laser using a fiber delivery system were visualized using the color Schlieren technique in combination with a polyacrylamide gel tissue model. Variable settings were used for emission mode, power, laser fiber distance, and laser duration, which were evaluated in every possible combination. Collateral thermal expansion and incision depth were measured. To validate the model, the results were compared to histology after CO₂ laser irradiation of ex vivo human vocal cords, and the intraclass correlation coefficient was calculated. Thermal damage and incision depth were measured by a blinded pathologist.

RESULTS

Of all parameters studied, duration of laser irradiation had the greatest effect on thermal expansion. Increased distance between laser tip and target tissue resulted in significantly reduced incision depth and increased thermal expansion. Pulsed emission modes led to increased incision depths. The intraclass correlation coefficient for consistency between the model setup and the ex vivo human vocal cords was classified as "fair."

CONCLUSIONS

By using high-intensity pulsed lasers at minimal distance to the target tissue, exposure times and subsequent damage to surrounding tissue can be reduced. If an evaporation technique is used, lower power in continuous wave at a larger distance to the target tissue will lead to superficial but broader thermal effects. The model setup used in this study is a valid model to investigate laser-induced thermal effects in vocal cord tissue.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:E680-E685, 2020.

Utility of Optical Coherence Tomography for Guiding Laser Therapy Among Patients With Recurrent Respiratory Papillomatosis

Importance

Recurrent respiratory papillomatosis (RRP) is a viral-induced disease caused by human papillomavirus and the second leading cause of dysphonia in children; however, neither a cure nor a definitive surgical treatment is currently available for RRP. Although laser therapy is often used in the treatment of RRP, the lack of real-time laser-tissue interaction feedback undermines the ability of physicians to provide treatments with low morbidity. Therefore, an intraoperative tool to monitor and control laser treatment depth is needed.

Objective

To investigate the potential of combining optical coherence tomography (OCT) with laser therapy for patient-tailored laryngeal RRP treatments.

Design, Setting, and Participants

This in vivo study was performed at the Massachusetts Eye and Ear Infirmary from February 1, 2017, to September 1, 2017. Three-dimensional OCT images were acquired before, during, and after photoangiolytic laser therapy in 10 pediatric patients with a history of papilloma growth who presented with lesions and hoarseness.

Main Outcomes and Measures

Whether intraoperative OCT monitoring of changes in optical scattering and absorption provides quantitative information to control thermal damage in tissue.

Results

Among the 10 pediatric patients (age range, 4-11 years; 6 male) included in the study, high-resolution OCT images revealed epithelial hyperplasia with clear RRP lesion margins. Images acquired during therapy indicated coagulation deep in tissue, and posttherapy images showed the ability to quantify the amount of tissue ablated by the photoangiolytic laser.

Conclusions and Relevance

Concurrent use of OCT imaging and laser therapy may improve postoperative outcomes for patients with RRP by delivering an optimal, patient-tailored treatment. Additional studies investigating the correlation between optical properties with vocal outcomes are required.

Safe Use of Flammable Endotracheal Tubes During Anesthesia for Laryngeal Laser Surgery-Report of 1024 Cases and a Brief Literature Review

INTRODUCTION

One of the major concerns in laryngeal laser surgery is the risk of airway fire. The introduction ofwrapped tubes and metal tubes has reduced the fire hazards. However, these tubes are expensive and do not provide convenient access to the surgical field. There are few laboratory studies addressing the resistance of polyvinylchloride tubes against ignition in the given circumstances. Nevertheless, its safety should be approved in clinical practices.

MATERIALS AND METHODS

This retrospective studyevaluated the airway management on 1024 patients undergoing laryngeal laser surgery. The data collection included the information about the type of endotracheal tube (ETT), mode of ventilation, and airway hazards (e.g., tube ignition).

RESULTS

Polyvinylchloride tubes and conventional positive pressure ventilation was applied for most of the patients (84.1%). The tube cuff was pierced with laser beam in 22 cases (2.5%). However, there was no case of ETT ignition or airway fire.

CONCLUSION

Polyvinylchloride tubes can be safely used in this subset of surgeries pending meticulous attention to the safety recommendations.

[Features of microsurgery of the vestibular larynx using CO and a diode laser]

The purpose of the study was to evaluate the possibility of using and the effectiveness of CO₂ and diode lasers in the microsurgery of the vestibular larynx. 85 surgical interventions were performed (using CO₂ laser - 45, diode - 40) on the vestibular larynx of 52 patients (papillomatosis, cicatricial stenosis, cysts, hyperplastic laryngitis, initial stage of laryngeal cancer). The complications, duration of the intervention and inflammatory changes after the operation were assessed. In 3 (3.5%) cases, the use of CO₂ laser was complicated by bleeding. The duration of the intervention with the use of a CO₂ laser averaged 24±5.6 minutes, with a diode laser 30±5.4 minutes (p<0.05). In patients with a diode laser, edema, mucosal congestion, fibrin and pain were significantly longer than patients after using a CO₂ laser (p<0.05). Thus, the use of CO₂ laser in the surgical treatment of the vestibular laryngeal region occurs with less time, a less prolonged inflammatory response, but in some cases requires additional methods of hemostasis.

[Papillomatosis of the larynx in children: the current state of the problem]

There is the authors have considered variants of modern methods of medical and surgical treatment of laryngeal papillomatosis in children in the review, based on the etiology of the disease. The analysis of the effectiveness of new methods of combined treatment with the use of modern technologies, taking into account their advantages and disadvantages. The possible prospects for further study problems and develop new methods of adjuvant therapy.

Current and future management of recurrent respiratory papillomatosis

Objectives

Recurrent respiratory papillomatosis (RRP) is a chronic disease of the respiratory tract that occurs in both children and adults. It is caused by the human papillomavirus (HPV), in particular low‐risk HPV6 and HPV11, and aggressiveness varies among patients. RRP remains a chronic disease that is difficult to manage. This review provides perspectives on current and future management of RRP.

Results

The current standard of care is surgical excision, with adjuvant therapies as needed. Surgical management of RRP has evolved with the introduction of microdebriders and photoangiolytic lasers; the latter can now be used in the office setting. Numerous adjuvant pharmacologic therapies have been utilized with some success. Also, exciting preliminary data show that HPV vaccines may prolong the time to recurrence in the RRP population. There is also optimism that wide‐spread HPV vaccination could reduce RRP incidence indirectly by preventing vertical HPV transmission to newborns.

Conclusion

To date, the biology of RRP is not well understood, although it has been noted to become more aggressive in the setting of immune suppression. Additional research is needed to better understand immune system dysfunction in RRP such that immunomodulatory approaches may be developed for RRP management.

Level of Evidence

4

Can "Indirect" Contact Laser Surgery be Used for Fluorescence-Image Guided Tumor Resections? Preliminary Results

Ensuring the complete removal of tumor tissue is the main challenge during resection operations. Recently, a technique of “indirect” contact laser surgery has been developed. In this study we assess the possibility of using such surgery for fluorescence image-guided tumor resection. Mouse colon adenocarcinoma CT-26 cells stably expressing the fluorescent protein mKate-2 was used as the tumor model. Resections of the tumor nodes were performed with either a scalpel blade, a laser scalpel with a bare tip, or a laser scalpel with a strongly absorbing coating on the fiber tip. Tumor-positive resection margins were detected using an IVIS Spectrum fluorescence imaging system. After tumor resection with the scalpel blade over half of the animals needed one additional resection to remove residual tumor cells. Animals in this group showed tumor recurrence within 7 days. Fluorescence imaging of the tumor bed, performed after resection to assess the presence of tumor cell clusters, was sufficiently effective only with a bloodless resection. The laser scalpels both with the bare tip and with the strongly absorbing coating on the tip provided such bloodless tumor resection in contact mode. Fewer animals required additional resections when the bare tipped scalpel was used and this also resulted in a reduction in tumor recurrence. After resections were carried out with the laser scalpel with the strongly absorbing coating on the tip, fluorescence was detected in the operative field and this led to undertaking additional resections, although subsequent investigation suggested that this was “false” fluorescence, resulting from the effects of the scalpel rather than the presence of residual tumor cells. The method of laser resection with a strongly absorbing coating on the tip therefore did not appear to demonstrate definite advantages over laser resection with a bare tip when removing tumors.

Investigation of the presence of HPV on KTP laser fibers following KTP laser treatment of papilloma

OBJECTIVES

Recurrent respiratory papillomatosis is often treated with in-office laser procedures using a potassium titanyl phosphate (KTP) laser transmitted through a laser fiber. Although effective, this procedure has notable downsides, including the possibility of transmitting human papillomavirus (HPV) in the smoke plume and the high cost of these single-use fibers. The objective of this study is to determine if HPV can be detected on a laser fiber after use, with or without sterilization.

METHODS

Twelve patients with laryngeal papillomas were treated with KTP laser energy transmitted via a KTP fiber. Ten fibers were sterilized in CIDEX (ASP, Irvine, California), a glutaraldehyde disinfectant, for 12 minutes, whereas two fibers were left unsterilized. Human papillomavirus DNA amplification was done on all 12 fiber samples with real-time polymerase chain reaction (PCR) using general primer mediated 5+ and 6+. Human papillomavirus genotyping detection was done using type specific probes and/or Sanger sequencing.

RESULTS

Over 27 strains of HPV were not detected on KTP fibers after use, with or without sterilization.

CONCLUSION

Human papillomavirus was undetectable by PCR on KTP laser fibers that were sterilized or unsterilized after use. Further studies are needed utilizing a transmission model to determine if HPV can be incubated from this fiber after sterilization.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:926-928, 2018.

Photothermal enhancement of chemotherapy in breast cancer by visible irradiation of Gold Nanoparticles

Photothermal Therapy (PTT) impact in cancer therapy has been increasing due to the enhanced photothermal capabilities of a new generation of nanoscale photothermal agents. Among these nanoscale agents, gold nanoshells and nanorods have demonstrated optimal properties for translation of near infra-red radiation into heat at the site of interest. However, smaller spherical gold nanoparticles (AuNPs) are easier to produce, less toxic and show improved photoconversion capability that may profit from the irradiation in the visible via standard surgical green lasers. Here we show the efficient light-to-heat conversion of spherical 14 nm AuNPs irradiated in the visible region (at the surface plasmons resonance peak) and its application to selectively obliterate cancer cells. Using breast cancer as model, we show a synergistic interaction between heat (photoconversion at 530 nm) and cytotoxic action by doxorubicin with clear advantages to those of the individual therapy approaches.

Coblation of suprastomal granulomas in tracheostomy-dependent children

OBJECTIVE

Suprastomal granulomas pose a persistent challenge for tracheostomy-dependent children. They can limit phonation, cause difficulty with tracheostomy tube changes and prevent decannulation. We describe the use of the coblator for radiofrequency plasma ablation of suprastomal granulomas in five consecutive children from September 2012 to January 2016.

METHOD

Retrospective case series at a tertiary medical center.

RESULTS

The suprastomal granuloma could be removed with the coblator in all 5 cases. Three were removed entirely endoscopically and 2 required additional external approach through the tracheal stoma for complete removal. There were no intraoperative or postoperative complications. One patient was subsequently decannulated and 2 patients have improved tolerance of their speaking valves. Two patients remain ventilator dependent, but their bleeding and difficulty with tracheostomy tube changes resolved. Three of the patients have had subsequent re-evaluation with bronchoscopy, demonstrating resolution or markedly decreased size of the granuloma. This technique is time efficient, simple and minimizes risks associated with other techniques. The relatively low temperature and use of continuous saline irrigation with the coblator device minimizes the risk of airway fires. Additionally, the risk of hypoxia from keeping a low fractional inspiratory oxygen level (FIO2) to prevent fire is avoided. The concurrent suction in the device decreases blood and tissue displacement into the distal airway.

CONCLUSION

Coblation can be used safely and effectively with an endoscopic or external approach to remove suprastomal granulomas in tracheostomy-dependent children. More studies that are larger and have longer follow-up are needed to evaluate the use of this technique.