Blue Light Laser Results in Less Vocal Fold Scarring Compared to KTP Laser in Normal Rat Vocal Folds

Preliminary Outcomes of the 445-nm Blue Light Laser for Stapedotomy

OBJECTIVE

To evaluate the efficacy of the 445-nm blue light laser in stapedotomy, compared with the CO2 laser.

PATIENTS

Patients 18 years or older with a history of otosclerosis who underwent stapedotomy with either carbon dioxide (CO2) or blue light (BL) laser from September 2020 to May 2024. Patients who had revision surgery, underwent stapedotomy without the use of CO2 or BL laser, or were without an available preoperative or postoperative audiogram were excluded.

INTERVENTION

Stapedotomy with the 445-nm BL laser.

MAIN OUTCOME MEASURE

Postoperative improvement in air-bone gap (ABG) on audiogram for patients who underwent stapedotomy with BL laser, as compared with those who underwent stapedotomy with CO2 laser.

RESULTS

Thirty-two patients were included in the final cohort, with 16 patients in the CO2 laser and BL laser groups, respectively. Although there was no significant difference in the postoperative ABG between the CO2 and BL laser groups (9.1 versus 6.5 dB, p = 0.27), there was a difference in the number of footplate fractures between the CO2 and TB laser groups, although this neither was significant (0 versus 3 events, p = 0.23) nor impacted hearing status.

CONCLUSION

The BL laser offers comparable closure of the ABG in stapes surgery, as well as a similar safety profile, when compared with the CO2 laser.

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.

445nm Blue Laser for Cricopharyngeal Myotomy/Zenker's Diverticulotomy: Proof of Concept and Use

OBJECTIVE(S)

Treatment for Zenker's diverticulum and cricopharyngeal dysfunction has evolved to include flexible endoscopic approaches. Currently, no flexible modalities combine the precision cutting of CO2 laser and the hemostasis of knife electrocautery. We present the first series describing fiber-based 445nm blue light (BL) laser for endoscopic cricopharyngeal myotomy/Zenker's diverticulotomy. We describe usage characteristics and laser parameters with rigid esophagoscopy to determine the feasibility of use with flexible endoscopy.

METHODS

Retrospective review and literature review.

RESULTS

The first nine cases of endoscopic diverticulotomy (n = 5) and cricopharyngeal myotomy (n = 4) with BL were reviewed. Rigid exposure was achieved with the Dohlman Slimline diverticuloscope. Mean age was 75.6 years. Average diverticulum depth was 0.89 cm ±1.0 cm. Pulsed mode was used in seven cases with mean of 6.86 W, 54 ms pulse on, and 286 ms pulse pause and overall mean of 6.00 W and 405 J. Complete myotomy with intact buccopharyngeal fascia and without bleeding limiting view was achieved in all patients. One of two patients in whom continuous wave setting was used developed subcutaneous emphysema following vigorous cough on POD0; this resolved after 7 days nothing per oral (NPO). Eight patients were started on oral intake without evidence for leak. Pulsed mode with fiber-to-tissue contact provided effective muscle cutting without disruption of buccopharyngeal fascia. Literature review yielded three articles examining flexible approach with laser for Zenker's and none with BL.

CONCLUSION

BL provides safe and effective fiber-based cutting and hemostasis in endoscopic cricopharyngeal myotomy/Zenker's diverticulotomy. Future use in flexible endoscopic approaches appears feasible, though continuous wave should be avoided.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:4620-4624, 2024.

Photoangiolysis with the 445-nm Blue Laser and the Potassium-Titanyl-Phosphate Laser: A Comparison

OBJECTIVES

Photoangiolytic lasers have yielded significant innovation in laryngeal surgery in the last 25 years. After the discontinuation of the potassium titanyl phosphate (KTP) laser, a novel 445-nm blue laser was developed. The optimal balance between a laser's desired tissue effects and collateral tissue damage is a major determinant of laser selection in microlaryngeal surgery. The shell-less incubation system for the chick chorioallantoic membrane (CAM) simulates the microvasculature of the human vocal fold and is useful for testing effects of laser settings and in simulated surgery. The aim of this study is to compare the tissue effects of the KTP and blue lasers using the shell-less CAM model.

METHODS

The shell-less incubation system contains: polymethylpentene film (used as a culture vessel), calcium lactate and distilled water supplementations. By using this system, the chick chorioallantoic membrane (CAM) can be fully exposed with a good field for surgery simulation. The effects of the 2 lasers (532 nm KTP and 445 nm blue) were quantified at clinically relevant energy settings and laser distances from target. Measures included imaging real-time vascular reactions in the CAM model, post-procedure histologic analysis of CAM tissue and temperature changes.

RESULTS

Vessel coagulation and rupture rates were less common with the blue laser compared with the KTP laser. Histologic analysis demonstrated less tissue disruption with the blue laser. Temperature changes were less with the blue laser.

CONCLUSION

In this CAM model with specific conditions, the blue laser reveals less tissue damage than the KTP laser. Suitable working distance and power setting of the laser are necessary for desired tissue effects.Level of Evidence: Level 3.

Recurrent respiratory papillomatosis: comparing in-office and operating room treatments

Objective

We report the management of recurrent respiratory papillomatosis (RRP) employing a protocol that includes both office-based (OB) and general anaesthesia (GA) procedures. Quality of life (QoL) outcomes in the OB cohort were compared to those obtained from an historical cohort treated only under GA.

Methods

Patients affected by RRP from 2019 until 2023 ("new protocol") and from 2012 to 2019 ("historical protocol") were enrolled. In both groups the Derkay site score (DSS) was calculated. In patients adhering to the new protocol, questionnaires measuring QoL were prospectively administered (voice handicap hindex-10 [VHI-10] along with a specific questionnaire to measure the tolerance to the OB procedures). A cost analysis was also performed.

Results

In all, 35 patients composed the new protocol cohort and 13 the historical. In the first group, patients underwent a median of 4 treatments. At 2 years, 68% of patients were treated exclusively in the office. Overall, for the new protocol, median DSS and VHI-10 after one year were both significantly lower than those at baseline [2 vs 4 and 3 vs 14, respectively; p < 0.001]. No differences were found between the new and the historical protocol cohorts considering DSS over time.

Conclusions

Treatment of RRP may be conducted successfully in an office-based setting reducing healthcare costs.

Comparison of Angiolytic Effects Between the 445-nm Blue Laser and 532-nm Pulsed KTP Laser

OBJECTIVE

This study aimed to compare the selective absorption of the 445-nm Blue laser (BL) and the 532-nm pulsed potassium-titanyl-phosphate (KTP) laser by blood vessels.

METHODS

Thirty-six chicken eggs at day 14 of incubation were dissected to expose the chick chorioallantoic membrane (CAM). Third-order vessels of the CAM were identified and irradiated using BL and KTP lasers using various settings at a laser-to-vessel distance of 3 mm using 0.4 mm fiber size. In total, 494 vessels segments were irradiated. Mean (standard deviation) number of irradiations for each setting was 26.0 (4.6), range from 15 to 39. Outcome measures included ablation rate (AR) and rupture rate (RR).

RESULTS

The two lasers were compared for AR and RR at long and medium pulse width (PW) associated with different power levels. At long PW (above 100 ms), BL showed significantly higher AR than KTP at high energy (600 mJ/pulse) and low energy (400 mJ/pulse); they did not show different AR and RR at medium energy levels (500 mJ/pulse). Using medium PW settings plus high and medium energy levels, BL and KTP showed relatively high AR and did not significantly differ in performance. However, at medium PW plus low energy (400-450 mJ/pulse), KTP showed significantly higher AR compared to BL.

CONCLUSION

At long PW, BL appeared to show higher AR than KTP at high or low energy levels, but they showed equivalent performance at medium energy. At medium PW, both performed similarly from high to medium energy, but KTP appeared to perform better than BL at lower energy settings.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:3220-3225, 2024.

Office-based blue laser therapy for vocal fold polyps and Reinke's edema: a case study and review of the literature

PURPOSE

To report the efficacy of blue laser in the treatment of vocal fold polyps and Reinke's edema in an office setting.

METHODS

The medical records and video-recordings of patients who underwent office-based blue laser therapy in a tertiary referral center for vocal fold polyps and/or Reinke's edema were reviewed. The primary outcome measures were the Voice Handicap Index-10 (VHI-10) score and disease regression. Acoustic and aerodynamic parameters were also analyzed.

RESULTS

Thirty-five patients (21 with vocal fold polyps and 14 with Reinke's edema) were included and a total of 47 lesions were treated. Out of the 35 patients, 7 patients were lost for follow-up. The mean VHI-10 score dropped significantly after surgery by 17.41 ± 8.67 points (p < 0.001). The endoscopic examinations of 38 lesions were reviewed (17 vocal fold polyps and 21 Reinke's edema) before and up to 6 months after laser therapy. In the subgroup with vocal fold polyps (N = 17), there was complete disease regression in 13 and partial in 4. In the subgroup with Reinke's edema (N = 21), there was complete disease regression in 7 and partial disease regression in 14. For patients with vocal fold polyp, there was a significant decrease in shimmer and a significant increase in maximum phonation time postoperatively. For patients with Reinke's edema, there was a significant decrease in shimmer and noise-to-harmonic ratio following treatment.

CONCLUSION

Office-based blue laser therapy is an effective treatment for vocal fold polyps and Reinke's edema leading to complete or partial disease regression. All patients had improvement in voice quality.

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.

Un-sedated Office-Based Application of Blue Laser in Vocal Fold Lesions

INTRODUCTION

Office-based laser procedures in laryngology have gained a lot of popularity in the last decade with the use of the KTP, PDL and Thulium lasers. Preliminary investigations currently report on the use of the 445 nm wavelength Blue laser for the treatment of various laryngeal pathologies, given its dual photoangiolytic and cutting properties.

OBJECTIVE

We aim to investigate the safety and efficacy of the Blue laser for the treatment of vocal fold lesions.

METHODS

This is a retrospective chart review of eleven patients with a variety of vocal fold lesions (polyps, Reinke's edema, papilloma, and leukoplakia), that underwent un-sedated office-based treatment using the 445 nm blue laser. The primary outcome was to compare preoperative to postoperative Voice Handicap Index (VHI-10) score and self-reported voice improvement using a visual analog scale (VAS). We also compared fiberoptic laryngeal examination before and after treatment.

RESULTS

Eleven un-sedated office-based procedures using the blue laser were performed. There was improvement in the mean VHI-10 score (n = 8) with a decrease from 15.13 ± 8.77 to 3.50 ± 3.46 (P= 0.015). Similarly, the mean VAS score (n = 7) decreased from 6.14 ± 1.21 to 1.71 ± 1.60 (P< 0.003). All patients had a complete or partial regression of the vocal fold lesions on fiberoptic laryngeal examination. None of the patients had complications after the procedure.

CONCLUSION

Blue laser therapy can be suggested as a safe and effective alternative treatment modality in office-based laryngology procedures for a variety of vocal fold lesions. A larger series is needed to better validate the efficacy of this laser as a new treatment modality.

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.

Dysplastic Lesions of the Larynx

There have been many advancements in the clinical and histologic diagnosis of laryngeal dysplasia (LD), but diagnosis still necessitates invasive histologic evaluation. Furthermore, despite improved histologic identification of dysplastic lesions, the exact details of pathophysiologic progression and the risk of malignant transformation is still uncertain. These unknowns create a barrier to establishing an ideal grading and classification system, which prevents the establishment of a precise and consistent treatment paradigm. Identifying these gaps in knowledge serves to highlight where further studies are warranted, ideally focusing on a better understanding of the biological behavior of LD. This would ultimately allow for the creation of a reliable grading and classification system and for the formalization of management and treatment guidelines for LD.

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.

Experimental model for controlled endoscopic subepithelial vocal fold injury in rats

Purpose:

To present a detailed, reproducible, cost-efficient surgical model for controlled subepithelial endoscopic vocal fold injury in the rat model.

Methods:

Six male Sprague Dawley rats were enrolled in the experiment. The left vocal folds were used to carry out the injury model, and the right vocal fold served as control. After deep sedation, the rats were placed on a custom operating platform. The vocal fold injury by subepithelial stripping was carried out using custom-made microsurgical instruments under endoscopic guidance. Data were analyzed for procedural time and post-procedural pain. Microcomputed tomography (micro-CT) scan and histologic images were obtained to assess the length, area, and depth of injury to the vocal fold.

Results:

The mean procedural time was 112 s. The mean control vocal fold length was 0.96 ± 0.04 mm. The mean vocal fold injury length was 0.53 ± 0.04 mm. The mean vocal fold surface was 0.18 ± 0.01 mm² with a mean lesion area of 0.05 ± 0.00 mm². Mean vocal fold injury depth was 375.4 ± 42.8 μm. The lesion length to vocal fold length ratio was 0.55 ± 0.03, as well as lesion area to vocal fold surface area was 0.29 ± 0.02.

Conclusions:

Our described experimental vocal fold injury model in rats is found to be fast, safe, cost-efficient, and reproducible with a rapid learning curve.

Vocal fold injury models in rats: a literature review on techniques and methodology

This study reviewed the current literature on technical aspects regarding controlled vocal fold injuries in the rat model. Data from PubMed, Embase, and Scopus database for English language literature was collected to identify methodological steps leading to a controlled surgical injury of the rat vocal fold. Inclusion criteria: full disclosure of anesthesia protocol, positioning of the rat for surgery, vocal fold visualization method, instrumentation for vocal fold injury, vocal fold injury type. Articles with partial contribution were evaluated and separately included due to the limited number of original methodologies. 724 articles were screened, and eleven articles were included in the analysis. Anesthesia: ketamine hydrochloride and xylazine hydrochloride varied in dose from 45 mg/kg and 4.5 mg/kg to 100 mg/kg and 10 mg/kg. Visualization: The preferred method was the 1.9 mm, 25-30 degree endoscopes. The widest diameter endoscope used was 2.7 mm with a 0 or 30 degree angle of view. Instruments for lesion induction range from 18 to 31G needles, microscissors, micro forceps to potassium titanyl phosphate, and blue light lasers. Injury types: vocal fold stripping was the main injury type, followed by vocal fold scarring and charring. One article describes scaffold implantation with injury to the superior aspect of the vocal fold. Rats are good candidates for in vivo larynx and vocal folds research. A more standardized approach should be considered regarding the type of vocal fold injury to ease data comparison.

Current approaches to management of vocal fold scar

PURPOSE OF REVIEW

Vocal fold (VF) fibrosis remains an insoluble problem in most cases, with a severe impact on vocal quality and effort. This review examines current investigations and research strands that explore the understanding of VF wound healing and applied treatments for the management of VF scar.

RECENT FINDINGS

Recent work focused on VF fibrosis has examined wound healing in the glottis, fibrosis-modifying medication, and tissue engineering approaches that span cytokine and growth factor therapy, scaffold and cell delivery platforms, seeded scaffolds, conditioned media and stem cell therapy. Many show promise and may deliver improvements in the wound bed favouring less fibrogenic healing patterns, ultimately with the goal of preserving or restoring VF vibration. Further collaborative research is required that examines combined approaches, long term outcomes, better three-dimensional modelling of cell-cell interactions and delivery modalities for molecular therapies.

SUMMARY

VF fibrosis research continues to expand and explore a variety of mechanistic pathways in order to understand VF healing and identify novel and complementary targets for manipulation. Many different approaches show promise and may also offer synergistic benefits. Research continues to strive for healing that more closely resembles true VF architecture and function.

Management of Laryngeal Dysplasia and Early Invasive Cancer

OPINION STATEMENT

Dysplasia and early laryngeal cancer lie on a spectrum of cellular changes. These start with early changes to the cells including epithelial hyperplasia and expand to dysplasia, squamous cell carcinoma in situ and finally developing in to invasive cancer. Dysplasia can range from low to high grade, with each being treated in a different manner. Treatment options are typically determined by where the dysplasia/invasive cancer lie on this spectrum along with the site within the larynx. Hyperkeratosis, mild dysplasia and moderate dysplasia typically involve primary endoscopic excision. Severe dysplasia and squamous cell carcinoma in situ involve primary endoscopic resection with the addition of possible laser resection and/or ablation. At this stage, surgery will be followed by close surveillance. Finally, early laryngeal cancer such as T1 and T2 lesions is typically more involved. Treatment depends on the site and degree of involvement of the structures, along with spread to surrounding structures. Typical treatment options of more involved early laryngeal cancer can range from radiation therapy, endoscopic transoral laser resection, endoscopic transoral robotic resection to open resection. Often times, my choice of treatment will be aimed at voice preservation but patient preference will also play a role in the decision making between treatment modalities. Chemotherapy and immunotherapy are typically not used in early stage laryngeal cancer.

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.