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.

Clinical Applications of Office-Based Laryngeal Surgery With KTP Laser

The pulsed photoangiolytic 532-nm potassium-titanyl-phosphate (KTP) laser has emerged in recent years as an efficacious treatment modality for vocal fold lesions. It also has broadened the indications for other laryngeal laser surgery. Features of KTP laser that it is a fiber-based delivery system and its energy is selectively absorbed by oxyhemoglobin make it suitable for office-based laryngeal procedures. An office-based KTP laser surgery provides an alternative management option for benign laryngeal diseases and can be performed comfortably under flexible endoscopic guidance which is placed through the nose of a fully awake patient. Office-based laryngeal surgery with a KTP laser can alleviate the need for general anesthesia. However, there are some limitations to apply due to reduced visual precision and the fact that the vocal folds are moving during procedures. Clinicians should carefully weigh the advantages and disadvantages of office-based procedures before a treatment option is selected. Patient selection and standardized laser energy parameters may help in decreasing complications and improving the treatment results.

Comparative Analysis of the Effectiveness of Modern Endoscopic Methods of Treatment of BPH

Lower urinary tract symptoms caused by benign prostatic hyperplasia are the most common urological problem among men, affecting about a third of men over the age of 50 Of all surgical treatments, monopolar transurethral resection of the prostate (TURP), in which enlarged prostate tissue is resected piece by piece using a monopolar electrode, has been the standard method since the 1970s. It can significantly improve maximum flow rate (Qmax), urination-related symptoms (based on the International Prostate Symptom Assessment Scale (IPSS)), and health-related quality of life with long-term efficacy compared to medications or other minimally invasive treatments [4]. Since the 2000s, new energy systems for surgery for benign prostatic hyperplasia have rapidly become popular, including systems using bipolar energy and various laser systems such as holmium laser, potassium titanyl phosphate (KTP) laser, thulium laser and diode laser Over the past 10 years, the trend in the surgical treatment of benign prostatic hyperplasia has shifted from monopolar TURP to laser therapy and bipolar TURP. Based on the data on the effectiveness of the HoLEP technique, it becomes clear that HoLEP is ready to replace all these methods as a new standard, based on almost two decades of data that consistently demonstrate its better results and lower complication rate. This review summarizes the available literature by comparing HoLEP and traditional BPH treatments that are widely used and have long-term efficacy data. Despite the fact that there is such a wide arsenal of surgical treatment of BPH, each of these methods has its own advantages and disadvantages. This review article contains a significant portion of the best randomized data directly comparing HoLEP with alternative surgical treatments.

Comparative efficacy and safety of transurethral laser surgery with holmium laser, KTP laser, 2-micron laser or thulium laser for the treatment of non-muscle invasive bladder carcinoma: a protocol of network meta-analysis

IntroductionThe potential of transurethral laser surgery in treating non-muscle invasive bladder cancer (NMIBC) has been confirmed, however which types of lasers may be preferentially prescribed remains a debate. The aim of this network meta-analysis is to investigate the comparative efficacy and safety of transurethral laser surgery with four common types of laser including holmium laser, potassium titanylphosphate (KTP) laser, 2-micron laser or thulium laser for the treatment of NMIBC.Methods and analysisA systematic search will be conducted to search all potentially eligible randomised controlled trials comparing different transurethral laser surgeries with each other or with standard transurethral resection among patients with NMIBC in PubMed, Embase, the Cochrane library, China National Knowledge Infrastructure, Wanfang database and Chongqing VIP from their inception until 31 May 2021. Two reviewers will be asked to independently select eligible studies, and assess the risk of bias of individual study with Cochrane risk of bias assessment tool. A random-effects network meta-analysis based on Markov chain Monte Carlo method will be carried out. Ranking probabilities will be considered to rank all laser types. Quantitative analysis will be carried out by using WinBUGS V.1.4.3.Ethics and disseminationEthical approval is not required because this is a network meta-analysis of published data. We will submit all findings to some conferences for preliminary communication and to a peer-reviewed journal for publication.Trial registration number10.17605/OSF.IO/TD9MW.

Outcome Comparison of KTP laser and CO2 laser excision for Laryngeal papillomatosis -- A Systematic Review

Background: CO2 laser and the 532-nm potassium titanyl phosphate laser (KTP) were developed to treat Laryngeal papillomatosis (LP); however, the difference in their outcomes remains unclear. Methods: A systematic review was conducted through a comprehensive search of three databases. Results: Overall, the cure rates were 87.25% in the KTP group and 75.98% in the CO2 group (p＜0.05). The complications rates were significantly different between the two groups (p<0.0001). In addition, there was no significant difference between the recurrence rates of the CO2 group and the KTP group (10% vs 9.8%). The risks of bias were 13.1±1.45 and 13.6±1.52 for CO2 group and KTP group respectively, which indicated the fair quality of evidence. Conclusions: The available fair-quality evidence suggested that KTP laser excision may be a better choice for LP. Following evaluations on the benefits of the two surgical techniques with more high-quality randomized controlled studies are needed.

Comparative Efficacy of the KTP Laser and Cold Steel in Office-Based Surgery for Oropharyngeal Papilloma

Objective: This study aims to compare the efficacy of the potassium-titanyl-phosphate (KTP) laser and cold steel surgery in treating oropharyngeal papilloma. Methods: Between 2017 and 2020, we enrolled 242 patients with oropharyngeal papilloma who were treated with either the KTP laser (n = 160) or cold steel surgery (n = 82). Patient charts were reviewed for demographic data (age and gender), pathology, anatomical location of lesions, operative duration, pain rating, residual disease, and recurrence. Results: The oropharyngeal papillomas were successfully removed in all patients, except one with a significant pharyngeal reflex. There was no significant difference in the average time for lesion resection between KTP laser and cold steel group (18.11 ± 13.96 s vs 19.43 ± 16.91 s, P > .05). However, all patients who underwent cold steel surgery experienced bleeding during the operation and required postoperative observation (about 20 min), making the total procedure time longer than that of the KTP laser procedure, which did not cause any intraoperative bleeding or require postoperative observation. After KTP laser treatment, the pain rating was .49 ± .98, whereas after cold steel surgery, it was .74 ± 1.12 ( P = .058). Twenty-five samples were sent for human papillomavirus (HPV) testing, and one tested positive for both HPV 6 and 11 strains, while another tested positive for HPV 16. No residual disease or recurrence was observed at the treatment sites after a long period of follow-up (M = 15.35 ± 10.79 mo; range = 6-39 mo). Conclusion: The KTP laser provided a better hemostasis effect and a good surgical field of vision during the operation, allowing the surgeon to complete the procedure in less time. No significant difference in terms of pain rating, incision recovery, and postoperative recurrence between the KTP laser treatment and cold steel surgery.

Risk of Airway Fire with the use of KTP Laser and High Flow Humidified Oxygen Delivery in a Laryngeal Surgery Model

Background 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. MethodsThe 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. ResultsFor every 10% increase in oxygen concentration above 60% the risk of flame increased by a factor of 2.3. Continuous laser setting at 2.6W 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. Conclusions 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.

Use of 532 nm Potassium Titanyl Phosphate Laser on Vocal Fold Scars Under Topical Anesthesia: A Pilot Study

Objective: This pilot study aims to evaluate the efficacy of 532 nm potassium titanyl phosphate (KTP) laser under topical anesthesia in patients with vocal fold scars. Methods: A series of 18 patients with vocal fold scars of varying degrees were treated. The KTP laser was used under local anesthesia in the outpatient clinic. It was set to deliver 6 W of power using a continuous output mode. Close-to-contact mode was used for laser irradiation, and contact mode was used for ablation and excision of the lesions. Some of the patients received laser scar ablation on both vocal folds; the scarred vocal fold on one side and the hypertrophic vocal fold on the other. Parameters include glottic closure, amplitude, and mucosal wave pattern were measured using laryngeal stroboscopic examination. Aerodynamic and voice evaluations were carried out using maximum phonation time (MPT), jitter, shimmer, Voice Handicap Index questionnaire (VHI-30), and GRBAS scale. Results: In total, 21 surgeries were performed on 18 patients. Glottic closure, amplitude, and mucosal wave pattern showed improvement 2 months postoperatively ( P < .05). There was significant improvement in the postoperative scores for VHI-30, VHI-emotional sub-scale, VHI-physical sub-scale, and GRBAS ( P < .05). There was no significant difference in the MPT and VHI-functional sub-scale before and after the operation ( P > .05). Re-adhesion of the anterior commissure was observed in 2 patients with Type III scars. Conclusion: The 532 nm KTP laser is an effective tool for the treatment of vocal fold scars. Further research is required to determine if serial laser applications could improve outcomes for this challenging condition. Level of Evidence: Level IV