Thulium laser in airway diseases in children

Management of Stridor in Severe Laryngomalacia: A Review Article

Laryngomalacia is the term most broadly used to portray the "internal breakdown of structures of supraglottis of the larynx at the time of inspiration. It is often associated with stridor during inspiration, which is of a high pitch at the time of birth and comes into notice by 14 days. When there is an increase in breathing, stridor worsens, and it is usually position-dependent. Laryngomalacia means the weakening of the larynx resulting in a collapse of the laryngeal cartilages, especially the epiglottis, into the airway. This partially occludes the upper airway during inspiration and causes inspiratory stridor. The exact etiology of the condition is not known. It is a well-known cause of noisy breathing in neonates and infants. The common presentation is a neonate with flushing and high-pitched inspiratory stridor that is usually noticed before 14 days of age. This worsens with breathing and supine positioning and improves in a prone position. Less commonly, it can present with hypoxia, feeding problems, aspiration, and failure to thrive. The condition may increase in severity during early life but usually self-resolves by two years of age. The hiccup-like squeak of laryngomalacia during inspiration is due to unsettled air flowing through the laryngeal passage. The condition is diagnosed with laryngoscopy, and the treatment varies with presentation and severity. Neonates with the uncomplicated disease can be treated expectantly. Those presenting with feeding problems and gastroesophageal reflux will require acid suppression. Severe complications like aspiration, severe airway obstruction, and hypoxia will require surgical treatment, including supraglottoplasty. In cases where the surgical treatment failed, noninvasive ventilation can be advised. The article reviews the various medical and surgical interventions and the management of severe laryngomalacia.

Soft robotic manipulator for intraoperative MRI-guided transoral laser microsurgery

Magnetic resonance (MR) imaging (MRI) provides compelling features for the guidance of interventional procedures, including high-contrast soft tissue imaging, detailed visualization of physiological changes, and thermometry. Laser-based tumor ablation stands to benefit greatly from MRI guidance because 3D resection margins alongside thermal distributions can be evaluated in real time to protect critical structures while ensuring adequate resection margins. However, few studies have investigated the use of projection-based lasers like those for transoral laser microsurgery, potentially because dexterous laser steering is required at the ablation site, raising substantial challenges in the confined MRI bore and its strong magnetic field. Here, we propose an MR-safe soft robotic system for MRI-guided transoral laser microsurgery. Owing to its miniature size (Ø12 × 100 mm), inherent compliance, and five degrees of freedom, the soft robot ensures zero electromagnetic interference with MRI and enables safe and dexterous operation within the confined oral and pharyngeal cavities. The laser manipulator is rapidly fabricated with hybrid soft and hard structures and is powered by microvolume (<0.004 milliter) fluid flow to enable laser steering with enhanced stiffness and lowered hysteresis. A learning-based controller accommodates the inherent nonlinear robot actuation, which was validated with laser path-following tests. Submillimeter laser steering accuracy was demonstrated with a mean error < 0.20 mm. MRI compatibility testing demonstrated zero observable image artifacts during robot operation. Ex vivo tissue ablation and a cadaveric head-and-neck trial were carried out under MRI, where we employed MR thermometry to monitor the tissue ablation margin and thermal diffusion intraoperatively.

One and half coblation supraglottoplasty: A novel technique for management of type II laryngomalacia

OBJECTIVES

Endoscopic supraglottoplasty is the mainstay surgical procedure in treatment of laryngomalacia. Various instruments have been used with coblation recently gaining widespread attention. Regarding the technique used, cutting the aryepiglottic folds is associated with rapid improvement but carries risk of restenosis while outer scar contracture method has delayed but established result. Therefore, this study was conducted to introduce a modified coblation supraglottoplasty technique gathering both benefits and evaluate its results and effectiveness.

METHODS

Retrospective study included patients diagnosed with type II laryngomalacia was conducted. Supraglottoplasty was done by "one and half coblation supraglottoplasty" technique which involves cutting of one aryepiglottic fold while the other one is laterally coagulated. Patients' basic and clinical data were assessed. Outcome measures included assessment of inspiratory stridor, failure to thrive, choking, cyanosis, lowest oxygen saturation levels and weight gain.

RESULTS

Seventeen patients were included in this study with a mean age of 3.71 ± 1.1 months. Significant statistical improvement was reached regarding stridor, failure to thrive and cyanosis. Also, minimal oxygen saturation and weight gain were significantly improved. None of the cases needed tracheostomy and no major postoperative complications occurred.

CONCLUSION

We conclude that "one and half coblation supraglottoplasty" is an effective and safe treatment for type II laryngomalacia with satisfactory outcomes.

LEVEL OF EVIDENCE

IV.

Supraglottoplasty in neonates and infants: A radiofrequency ablation approach

BACKGROUND

Supraglottoplasty is the mainstay of surgical treatment for laryngomalacia. A novel supraglottoplasty surgical technique is needed to achieve better efficacy. The purpose of this study was to introduce modified microscopic radiofrequency ablation supraglottoplasty (MMRAS) for the treatment of congenital laryngomalacia and to evaluate the outcome and effectiveness of this novel approach.

METHODS

Seventeen children with severe laryngomalacia who underwent MMRAS were studied retrospectively. Supraglottoplasty of type III laryngomalacia was different from classical method. All the patients were kept intubated for 5 days after surgery to achieve a better epiglottal position and to avoid reconglutination of aryepiglottic folds. The patients' demographic information, symptoms, comorbidities, type of laryngomalacia, synchronous airway lesions and final outcomes were examined.

RESULTS

The median age at the time of surgery was 3.36 months (3 months 10 days). Operative indications included feeding difficulties, noisy breathing or respiratory distress (or both), and sleep-related symptoms. The MMRAS success rate was 82.4%. Most patients were extubated successfully on postoperative day 5. The major postoperative complication was pulmonary infection which occurred in 3 cases (17.6%) and required anti-infective therapy. No perioperative deaths and no long-term complications occurred. Failures were observed in 3 (17.6%) of 17 cases, 2 patients presented with a neurological disease and required tracheostomy, 1 patient relapsed because of postoperative adhesions and later underwent revision supraglottoplasty.

CONCLUSIONS

From these results, we conclude that MMRAS is an effective and safe treatment for symptomatic laryngomalacia and has the potential to provide better breathing, feeding, and sleeping outcomes in children with severe laryngomalacia. Postoperative intubation for 5 days may result in better therapeutic outcomes. Multicenter cooperative studies of comparison between MMRAS and conventional approaches would lend further evidence-based support for this surgical method.

Lasers in stapes surgery: a review

Background:

Lasers in stapes surgery are used to divide the anterior and posterior crus of the stapes, divide the stapedius tendon and perforate the footplate. The ideal laser should not penetrate deeply into the perilymph (thereby increasing its temperature). It should be conducted through optical fibres, allowing easy manipulation, and should have good water absorption, equating to high bone ablation efficiency.

Objectives:

This review discusses the various different lasers used in stapes surgery with regard to their properties and suitability for this type of surgery. In particular, the laser parameters used are discussed to facilitate their clinical use.

Endobronchial therapy with a thulium fiber laser (1940 nm)

BACKGROUND

Nd:YAG laser (1064 nm) is standard in bronchology. The thulium fiber laser (1940 nm) has a nearly 1000-fold increased absorption in water, enabling precise tissue ablation with a small margin of coagulation, whereas 1064-nm laser light penetrates deeper into tissue with less controllable effects.

OBJECTIVES

To assess the safety, feasibility, and versatility of endobronchial thulium laser therapy in an observational cohort study.

METHODS

Endobronchial treatment with the thulium fiber laser was performed in a cohort study of 187 bronchoscopies on 132 consecutive patients with 135 endobronchial lesions amenable to laser resection.

RESULTS

The thulium fiber laser produced superficial, precise, and rapid tissue ablation. Eighty-one lesions were completely vaporized; 82 lesions were treated by deep tissue destruction by inserting the fiber into tissue followed by mechanical resection. Tumor bleeding was coagulated with rapid and sustained hemostasis (n = 28). Nitinol stents were removed after resection of severe granulation tissue overgrowth (n = 10). Intact stents were maintained after ablation of in-stent tissue (n = 47). In 11 cases, bleeding occurred during laser treatment (n = 11 of 187). Power settings between 5 and 20 W were found to be safe.

CONCLUSIONS

Endobronchial therapy with the thulium laser at 1940 nm seems to be safe, feasible, and highly versatile for treatment of airway stenosis and stent obstruction caused by tissue ingrowth. Further studies are warranted.

Management of laryngomalacia

Laryngomalacia is the most common laryngeal disease of infancy. It is poorly tolerated in 10% of cases, requiring assessment and management, generally surgical. Surgery often consists of supraglottoplasty, for which a large number of technical variants have been described. This surgery, performed in an appropriate setting, relieves the symptoms in the great majority of cases with low morbidity. However, few data are available concerning the objective results: preoperative and postoperative objective assessment of these infants is therefore necessary whenever possible. Noninvasive ventilation (NIV) may be indicated in some infants with comorbid conditions or failing to respond to surgical management.

A 2-microm continuous-wave laser system for safe and high-precision dissection during NOTES procedures

INTRODUCTION

Lasers 2-microm in wavelength offer efficient tissue cutting with limited thermal damage in biological tissue.

OBJECTIVE

To evaluate the dissection capabilities of a 2-microm continuous-wave laser for NOTES procedures.

METHODS AND PROCEDURES

We conducted 18 acute animal experiments. Group 1 (three animals): transcolonic access to the peritoneal cavity (15-W transcolonic laser puncture, balloon dilation over the laser probe). Group 2 (six animals): transcolonic access with needle-knife puncture and balloon dilation. Group 3 (three animals): transgastric access to the peritoneal cavity (similar technique as group 1) followed by laser-assisted dissection of the kidney. In one animal of group 3, a therapeutic target (hematoma) was created by percutaneous puncture of the kidney. Group 4 (six animals): transgastric access (similar to the technique of group 2).

RESULTS

Translumenal access to the peritoneal cavity was achieved in 2-3 min in group 1 (significantly shorter than with the needle-knife-assisted technique, 4-5 min, p=0.02) and in 7-10 min in group 3 (compared to 6-17 min in group 4, p=0.88). In group 3, laser dissection of the parietal peritoneum and of perinephric connective tissue allowed access to the retroperitoneum with complete removal of a blood collection in the animal with puncture trauma. Laser dissection demonstrated good maneuverability, clean and rapid cutting, and excellent hemostasis. Peritoneoscopy and necropsy showed no damage of targeted tissue and surrounding organs.

CONCLUSIONS

The 2-microm continuous-wave laser system showed promising capabilities for highly precise and safe dissection during NOTES procedures.