YAG Laser Resection Research Articles

Precision resection of pulmonary tuberculoma using Nd:YAG-laser

The objective of the study: a comparative study of immediate and long-term results of pulmonary tuberculoma precision resection with Nd:YAG-laser with a wavelength of 1,318 nm and atypical resection with suturing devices.Subjects and Methods. Two groups of 58 patients each were compared. The groups were comparable in terms of gender, age, the nature of the concomitant pathology and the main pathological process. In Group I, patients were operated on using precision 1,318-nm Nd:YAG-laser resection, and in Group II, the sublobar resection with suturing devices were used.Results. The mean duration of hospital stay in Groups I and II was 19.10 ± 6.02 and 19.20 ± 6.02 days respectively (p > 0.05), the duration of surgery made 65 [55; 75] and 55 [45; 60] minutes (p > 0.05), the mean volume of surgical blood loss was 50 [33; 70] and 70 [50; 165] ml (p > 0.05), and the mean duration of pleural cavity drainage after surgery was 4 [3; 5] and 4 [3; 6] days (p > 0.05). Statistically significant differences were noted in the mean volume of the resected part of the lung: 14.0 ± 7.4 mm3 in Group I versus 95.0 ± 9.7 mm3 in Group II (p ≤ 0.05). The complete clinical and radiological cure was achieved in 70% of patients in Group I and 82% in Group II. According to MSCT data, in 91.6% of cases, a thin linear scar is formed in the area of precision intervention.Conclusion: The surgical methods are comparable in terms of immediate and long-term results but precision laser resection minimizes the removal of intact tissue during the removal of tuberculomas.

Ureteral polyps protruding from the urethra

BackgroundUreteral fibro-epithelial polyp (UFP) is a rare benign ureteral tumor, and surgical removal of the polyps is still the preferred solution. Although many cases have reported polyps extending to the bladder, our case was the first to report a huge UFP that underwent endoscopic laser resection to highlight the urethra and cause severe end hematuria permanently.Case presentationIn 2019, a 37-year-old woman came to the hospital because of hematuria and a dark red extraurethral mass. CTU inspection showed: filling defect between the right ureter and the bladder at the entrance of the bladder. After ureteroscopy, it was found that the ureteral mass came out of the urethral orifice. Then, under the direct view of the ureteroscope, a Ho:YAG laser was used to remove the tumor by cutting off along the its base, and the patient was discharged 3 days after the operation.ConclusionUrethral polyps from the ureter should be considered in the differential diagnosis of urethral neoplasms. Ho:YAG laser resection under ureteroscopy is an effective option for treating UFP, but be careful of ureteral stricture after surgery.

Suturing of the laser resection area is recommended over a depth of 2 cm in an experimental porcine lung model.

Lung metastases can be removed by an Nd:YAG laser to save lung parenchyma. At these sites, a coagulated lung surface remains. Airtightness was investigated in relation to the depth of resection on an ex vivo porcine lung model. Freshly slaughtered porcine double lung preparations were connected to a ventilator via a tube. Non-anatomical laser resections were performed with an 800 µm laser fiber and the Nd:YAG laser LIMAX® 120 (power: 40 and 60 watts). The following resection depths (each n=12) from the lung surface were examined: 0.5, 1, 1.5 and 2.0 cm. After resection the lungs were submerged under water and ventilated (frequency 10/min, Pinsp =25 mbar, PEEP =5 mbar). Airtightness of resection surfaces was determined by a leakage score, as well as the measurement of the leakage volume (in mL) per respiration (Group 1). Afterwards, the resection areas were coagulated for 5 seconds with a laser power of 60 watts at a distance of approximately 1 cm from the surface. This was followed by a re-evaluation for airtightness (Group 2). Finally, the resection surface was closed by a suture (PDS USP 4-0) and re-tested for airtightness (Group 3). The individual groups were compared for their significance (P<0.05) using a nonparametric test. Up to a resection depth of 1.5 cm, the ventilated resection surfaces were completely airtight regardless of the laser power. From a depth of resection of 1.5 cm, a mean air volume loss of 28.9±5.3 mL/respiratory cycle at 40 watts and of 26.4±5.8 mL at 60 watts was found. Additional surface coagulation did not significantly reduce the leakage rate. In contrast, suturing significantly reduced (P<0.0001) to 7.2±3.7 mL/ventilation (40 watts) and 6.0±3.4 mL/ventilation. At a resection depth of 2 cm, the leakage volume was 42.9±3.3 mL/respiratory cycle (40 watt) and 46.3±6.4 mL/respiratory cycle (60 watt). Additional surface coagulation failed to significantly reduce leakage volume, but suture closure provided airtightness. In non-ventilated porcine lungs, Nd:YAG laser resection surfaces up to a resection depth of 1.5 cm are airtight after ventilation onset. From a depth of 1.5 cm, closure of resection surfaces by an additional suture is needed. Airtightness of resection surfaces was not increased by additional coagulation.

Almost 50 Years of Nd:YAG Laser Resection in Pulmonary Metastasectomy - Lessons Learned from This Period

Objectives: The use of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser is a widely performed procedure in the surgical therapy of pulmonary metastases. The Nd:YAG offers the ability of cutting and coagulating. This laser system permits the resection of centrally located metastases because it allows a precise excision and the protection of the bronchus or vessels. After the first experimental studies on the laser resection of pulmonary lesions in the 1960s and the following technical improvement, we decided to search for all available studies and summarize the available evidence.

Airtightness of lung parenchyma without a closing suture after atypical resection using the Nd:YAG Laser LIMAX(R) 120

Lung metastases can be non-anatomically resected with a Nd:YAG Laser. It is recommended that the resected lung surface be sealed by slowly resorbable sutures. However, the lung tissue may be restricted by the sutures once it is re-ventilated. Thus, it was analysed whether the lung parenchyma is airtight after laser resection without suturing the defect. The pulmonary artery of unimpaired paracardial lung lobes of freshly slaughtered pigs (mean weight 46 g) was cannulated and rinsed out via a hypotonic saline-heparin solution (5000 IE) until the perfusate was clear of body fluid. The lobular bronchus was connected to an airtight ventilation tube (Fa. VYGON 520 3.5 oral tube) and ventilated pressure-controlled (PEEP + 5 cm H₂O, P₁ = 20 cm H₂O, frequency = 10/min) via a respirator. All lobes were perfused with Ringer solution at 42°C at normothermia and normotonia. In group 1 (n = 8), an atypical peripheral parenchymal resection (average resected surface: 2 × 2 cm(2)) and in group 2 (n = 8), a deep atypical parenchymal resection (average resected surface: 4 × 4 cm(2)) were performed with the Nd:YAG Laser LIMAX 120 (output power at 100 watts). After post-resection ventilation of 15 min, the resection surface was tested for airtightness and burst pressure. All group 1 lobes tested airtight under pressure-controlled ventilation. The mean burst pressure was 34.4 mbar (SD ± 3.2 mbar). Six lobes of group 2 were also completely airtight. The remaining two lobes, however, revealed a serious parenchymal leak (score 3). This was caused by the cross-opening of a segmental bronchus, although the surrounding lung parenchyma was also airtight. The mean burst pressure of these lobes was 31.7 mbar (SD ± 4.08 mbar). There was no significant difference between the two groups (P = 0.12). Peripheral lung defects after Nd:YAG Laser resection might not be sutured, since the laser-induced vaporization of the lung parenchyma seems to be initially airtight. These experimental data warrant confirmation in a controlled clinical study.

AB 101. Update on interventional bronchology techniques.

In recent years rapid development of technology led to the increase in number of interventional bronchology techniques available for use in respiratory endoscopy units (REU). Many of techniques are not readily available for routine use in bronchology, however their appliance significantly increases diagnostic and therapeutic efficacy of bronchoscopy. Among diagnostic interventional bronchoscopy techniques recently advanced in REU of the Institute for pulmonary diseases of Vojvodina most facilitating are autofluorescence videobronchoscopy (AFI), narrow band imaging videobronchoscopy (NBI), radial and linear endobronchial ultrasound (EBUS). In recent years REU team published several significant clinical trials in domain of AFI, NBI and EBUS. These techniques became routine diagnostic tools for detection of lung cancer, tuberculosis, sarcoidosis, and other respiratory disorders. Therapeutic interventional bronchoscopy techniques routinely used in treatment of malignant and non-malignant central airway obstruction are Nd:YAG laser resection, argon plasma coagulation, electrocautery, endobronchial brachytherapy, cryotherapy and tracheobronchial stenting. All of the techniques, except of stenting, are readily available for routine use at the REU. Large number of clinical trials in domain of therapeutic interventional pulmonology was in recent years published by the team of REU. Further development and improvement in use of diagnostic and therapeutic interventional pulmonology techniques is required in order to facilitate quality of medical care. Joint clinical trials with partners in EU and other countries would increase the quality of research and publications. Acquisition of more advanced techniques for diagnosis and treatment of respiratory diseases (electromagnetic navigation bronchoscopy, LungPoint virtual bronchoscopic navigation, technology for endobronchial lung volume reduction, bronchial thermoplatsy systems, etc) is one of the priorities of REU team at the Institute for Pulmonary Diseases of Vojvodina.

Results of interventional bronchoscopy in the management of postoperative tracheobronchial stenosis

To investigate the role of bronchoscopic intervention in the management of postoperative tracheobronchial stenosis, a retrospective study was performed at a tertiary referral hospital. Thirty patients who underwent 106 bronchoscopic interventions between January 2000 and July 2010, including ballooning, bouginage, Nd:YAG laser resection, and stent insertion, were included and followed up for a median of 34 months. Silicone stents were required in 19 of 30 patients (63%) to maintain airway patency. Bronchoscopic intervention provided improvement of dyspnea in 97% of the patients. After airway stabilization, the stents were removed successfully in 7 of 19 patients (37%) a median of 7 months after insertion. In 3 patients (10%), the intervention failed to widen the airway. There were no procedure-related deaths or cases of pneumonia, although additional interventions were needed in 9 patients (30%) within 30 days. Stent-related late complications (70%), such as restenosis (43%), overgrowth of granulation tissue (33%), stent migration (32%), mucostasis (30%), and malacia after stent removal (16%), were controllable at follow-up bronchoscopy. Bronchoscopic intervention could be a useful treatment modality for patients with postoperative tracheobronchial stenosis when surgery is not feasible.

Patient-related independent clinical risk factors for early complications following Nd: YAG laser resection of lung cancer.

INTRODUCTION:Neodymium:yttrium aluminum garnet (Nd:YAG) laser resection is one of the most established interventional pulmonology techniques for immediate debulking of malignant central airway obstruction (CAO). The major aim of this study was to investigate the complication rate and identify clinical risk factors for complications in patients with advanced lung cancer.METHODS:In the period from January 2006 to January 2011, data sufficient for analysis were identified in 464 patients. Nd:YAG laser resection due to malignant CAO was performed in all patients. The procedure was carried out in general anesthesia. Complications after laser resection were defined as severe hypoxemia, global respiratory failure, arrhythmia requiring treatment, hemoptysis, pneumothorax, pneumomediastinum, pulmonary edema, tracheoesophageal fistulae, and death. Risk factors were defined as acute myocardial infarction within 6 months before treatment, hypertension, chronic arrhythmia, chronic obstructive pulmonary disease (COPD), stabilized cardiomyopathy, previous external beam radiotherapy, previous chemotherapy, and previous interventional pulmonology treatment.RESULTS:There was 76.1% male and 23.9% female patients in the study, 76.5% were current smokers, 17.2% former smokers, and 6.3% of nonsmokers. The majority of patients had squamous cell lung cancer (70%), small cell lung cancer was identified in 18.3%, adenocarcinoma in 3.4%, and metastases from lung primary in 8.2%. The overall complication rate was 8.4%. Statistically significant risk factors were age (P = 0.001), current smoking status (P = 0.012), arterial hypertension (P < 0.0001), chronic arrhythmia (P = 0.034), COPD (P < 0.0001), and stabilized cardiomyopathy (P < 0.0001). Independent clinical risk factors were age over 60 years (P = 0.026), arterial hypertension (P < 0.0001), and COPD (P < 0.0001).CONCLUSION:Closer monitoring of patients with identified risk factors is advisable prior and immediately after laser resection. In order to avoid or minimize complications, special attention should be directed toward patients who are current smokers, over 60 years of age, with arterial hypertension or COPD.

ND:YAG LASER RESECTION CAN IMPROVE SYMPTOM CONTROL, PROGRESSION FREE PERIOD AND SURVIVAL IN SELECTED LUNG CANCER PATIENTS

PURPOSE: Purpose of the study was to evaluate the effect of Nd:YAG laser resection of centrally located tumors on various symptoms, signs, time to progression and survival in lung cancer patients. The question is how effective can laser resection be in symptom control, time to progression and can it influence survival of lung cancer patients?.

Nd:YAG laser resection of lung cancer invading the airway as a bridge to surgery and palliative treatment

Background. Thirty percent of patients with lung cancer have airway obstruction requiring palliation. In addition, endoscopic resection may be considered before surgery or induction therapy to improve quality of life and functional status, and to allow better staging. It may also help to prevent infectious complications during induction chemotherapy. Methods. Since 1993, 351 Nd:YAG laser resections were performed in 273 patients with lung cancer. The tumor involved the trachea in 36 patients, the carina in 28, the main bronchi in 154, the bronchus intermedius in 29, and the distal airway in 26. One hundred eight stents were placed. After the endoscopic treatment 36 patients were operated on (23 after induction chemotherapy) with 8 pneumonectomies (1 tracheal sleeve) and 28 lobectomies (15 bronchial sleeves). Spirometry, arterial blood gas analysis, and quality of life and performance status were recorded before and after laser treatment and after induction chemotherapy. Complications during chemotherapy, surgical morbidity and mortality, and survival were also recorded. Results. Major complications during laser resection were bleeding (7 patients) and hypoxia (5 patients). Three patients died within 24 hours after the procedure. No complications were observed in the group of patients who subsequently underwent induction chemotherapy or surgery. One patient developed pneumonia during induction chemotherapy. The airway caliber improved in 89% of patients undergoing palliation only. In the group of patients undergoing induction chemotherapy and/or surgery, the performance status, quality of life, and functional measurements significantly improved after endoscopic treatment (FEV 1 from 1.4 ± 0.5 L/s to 2.2 ± 0.6 L/s). Three-year survival after induction chemotherapy and surgery, was 52%. Median survival after palliation alone was 12.1 months. Conclusions. Nd:YAG laser resection is a safe and effective means of relieving airway obstruction. Before induction chemotherapy or surgery preliminary endoscopic palliation helps to improve evaluation and staging and contributes to reducing morbidity during chemotherapy without increasing surgical complications.

Using a Chest Laryngoscope Holder to Facilitate Rigid Bronchoscopic Nd:YAG Laser Photoresection

Laser therapy is indicated for the resection of lesions of the main airways. Laser photoresection of larynx and tracheobronchial obstructive processes can be performed with rigid (RB) or flexible bronchoscopes (FFB). We describe the use of the chest laryngoscope holder as an option when performing laser resection of tracheobronchial lesions. Advantages of this technique include the free handling of endoscopic and laser instruments. Our experience in 36 cases of Nd:YAG laser resection performed in this manner is presented. Potential disavantages of this technique are also described.

TRANSURETHRAL HOLMIUM LASER RESECTION OF THE PROSTATE

We evaluated the efficacy of the holmium:YAG laser for transurethral endoscopic prostatectomy for benign prostatic hyperplasia (BPH).We treated 103 patients with BPH with holmium:YAG laser resection of the prostate. A high power holmium laser generating a maximum of 60 or 81 W. was used in a pulsed mode, applying energy directly to prostatic tissue via a forward firing 550 micron. fiber transurethrally under direct vision. Treatment outcome was evaluated by the International Prostate Symptom Score, quality of life score, maximum flow rate and post-void residual urine volume. We also compared holmium laser surgery and transurethral resection of the prostate for operative factors, such as surgical duration, bleeding volume and catheterization time.Average symptom score, quality of life score, peak flow rate and post-void residual significantly improved at 1 week, 1 month and 3 months postoperatively, with improvement maintained up to 36 months postoperatively in the holmium:YAG group. Intraoperative bleeding volume was significantly lower and catheterization time was significantly shorter for holmium:YAG than for transurethral prostatic resection. Use of the holmium laser caused no complications.Because of its effectiveness and safety holmium:YAG resection is a viable potential surgical alternative for symptomatic BPH. The holmium:YAG laser has been verified to be useful for many purposes in urology.

TRANSURETHRAL HOLMIUM LASER RESECTION OF THE PROSTATE

We evaluated the efficacy of the holmium:YAG laser for transurethral endoscopic prostatectomy for benign prostatic hyperplasia (BPH). We treated 103 patients with BPH with holmium:YAG laser resection of the prostate. A high power holmium laser generating a maximum of 60 or 81 W. was used in a pulsed mode, applying energy directly to prostatic tissue via a forward firing 550 micron. fiber transurethrally under direct vision. Treatment outcome was evaluated by the International Prostate Symptom Score, quality of life score, maximum flow rate and post-void residual urine volume. We also compared holmium laser surgery and transurethral resection of the prostate for operative factors, such as surgical duration, bleeding volume and catheterization time. Average symptom score, quality of life score, peak flow rate and post-void residual significantly improved at 1 week, 1 month and 3 months postoperatively, with improvement maintained up to 36 months postoperatively in the holmium:YAG group. Intraoperative bleeding volume was significantly lower and catheterization time was significantly shorter for holmium:YAG than for transurethral prostatic resection. Use of the holmium laser caused no complications. Because of its effectiveness and safety holmium:YAG resection is a viable potential surgical alternative for symptomatic BPH. The holmium:YAG laser has been verified to be useful for many purposes in urology.

Holmium: YAG laser resection of the prostate.

The holmium laser is a relatively new multipurpose medical laser that recently became available for use in urology. There has been considerable interest in this device, as it seems to combine the cutting properties of the carbon dioxide laser with the coagulating properties of the neodymium:YAG laser, making it particularly appealing for many surgical applications. The last decade has seen enthusiasm for the use of laser energy for the treatment of benign prostatic hyperplasia. In this article, we review the technique of Ho:YAG laser resection of the prostate, including the essential equipment and perioperative patient care.

Radiation Therapy for Tracheobronchial Amyloidosis

A 67-year-old man presented with localized tracheobronchial amyloidosis involving the distal trachea and the right-sided airways. The disease caused right middle lobe collapse and threatened the right upper and lower lobes. A variety of bronchoscopic methods, including Nd:YAG laser resection, dilation, and stenting, were used as temporizing methods. External beam radiation therapy, considered because of disease progression, caused a measurable local response. Radiation therapy should be considered as a treatment option for localized tracheobronchial amyloidosis causing airway obstruction.

Application of the Holmium:YAG Laser for Prostatectomy

The authors review the current knowledge regarding the application of the Holmium: YAG laser for prostatectomy. Conventional surgical therapies for benign prostatic hyperplasia (BPH) are effective but associated with relatively high morbidity. Laser prostatectomy, using either Neodymium:YAG or potassium-titanyl-phosphate lasers, has emerged as a new and much safer operative approach to relieve symptoms of benign prostatic hyperplasia. However, these laser wavelengths possess key disadvantages that have limited their acceptability and dissemination in everyday urologic practice. THE authors review their own extensive experience in the development of clinical application of Holmium: YAG laser technology for prostatectomy, as well as the published reports in the current medical literature now dealing with this subject. In multiple clinical trials, Holmium:YAG laser resection of the prostate has proven efficacious in relieving symptomatic BPH. Both objective urodynamic measures of voiding outcomes and symptomatic improvement have been shown to be equivalent to standard electrocautery resection of the prostate. At the same time, these studies have demonstrated the superior safety and hemostasis of Holmium:YAG laser prostatectomy compared to electrocautery resection, similar to prior laser prostatectomy procedure. Unlike prior forms of laser prostatectomy, Holmium:YAG laser resection of the prostate acutely removes all obstructing prostate tissue, so that the postoperative catheterization requirement is typically only overnight and improvement in voiding is immediate. Current operative techniques and the latest technological developments to facilitate Holmium:YAG laser prostatectomy are described. Holmium: YAG laser prostatectomy combines the best features of prior laser prostatectomy technologies, including minimal complications and morbidity, with the efficacy and immediacy of voiding outcomes associated with conventional electrocautery resection of the prostate.

Holmium: YAG laser resection of prostate (HoLRP) for patients in urinary retention.

We examined the holmium:YAG (Ho:YAG) laser as a tool to perform acute resection of obstructing prostatic tissue in the subgroup of men with benign prostatic hyperplasia (BPH) who present in urinary retention. A total of 36 men presented in acute urinary retention requiring catheterization before undergoing Ho:YAG laser resection of the prostate (HoLRP). Their mean age was 67 years. The mean laser energy delivery was 102 kJ (range 42-315 kJ). The mean postoperative catheterization time was 1.5 days (range 1-8 days), and only 3 men required a catheter for more than 48 hours. There were no acute perioperative complications. Improvement in voiding was immediate and sustained through 6 months of follow-up. At 6 months, the mean peak urinary flow rate was 22.5 mL/sec, and the AUA Symptom Index Score was 5.7. A meatal stricture requiring dilation in one man represents the sole late complication observed in this series. Late recurrence of urinary retention has occurred in two men who had contributing medical problems, for an overall treatment failure rate of 5.6%. Thus, HoLRP represents an effective surgical therapy for patients with bladder outlet obstruction presenting in urinary retention. Morbidity is minimal compared with electrocautery resection, while the efficacy and immediacy of voiding improvement appear similar.

Upper Airway Obstruction Secondary to Acinic Cell Carcinoma of the Trachea: Use of Nd:YAG Laser

Comprising 1 to 4% of all tumors and 7 to 15% of malignant neoplasms of the major salivary glands, acinic cell carcinoma (ACC) rarely occurs in the respiratory tract. There has been only one case of ACC of the trachea previously reported in the medical literature. A second case of ACC of the trachea associated with upper airway obstruction and its management by Nd: YAG laser and surgical resection is reported.

Delayed Bronchial Stenosis After Blunt Chest Trauma

Delayed Bronchial Stenosis After Blunt Chest Trauma

Endobronchial radiation therapy with or without neodymium yttrium aluminum garnet laser resection for managing malignant airway obstruction

Previous reports have shown low-dose-rate (LDR) afterloading Ir-192 endobronchial radiation therapy (EnBRT) to effectively palliate symptoms in patients with malignant airway obstruction. The authors retrospectively assessed the consequences of LDR EnBRT with or without neodymium yttrium aluminum garnet (Nd:YAG) laser resection in 37 patients. Between February 1986 and June 1991, 37 patients with malignant airway obstruction were treated with LDR EnBRT at The Cleveland Clinic Foundation. Inclusion criteria for LDR EnBRT with or without Nd:YAG laser resection were patients with recurrent, symptomatic endobronchial lesions treated previously with external beam irradiation. Of the 37 patients, 21 patients with endobronchial lesions underwent Nd:YAG laser resection; 16 patients with mainly extrinsic lesions received EnBRT only. Before EnBRT, selected patients (7 of 16 in the nonlaser-treatment group and 14 of 21 in the laser-treatment group) received additional external beam treatments of 2000 cGy/10 fractions. The LDR afterloading Ir-192 technique was used to deliver approximately 30 Gy to a 1.0-cm radius target. All patients had one or more of the following symptoms: 1) dyspnea, 2) fever, 3) cough, and 4) hemoptysis. Good-to-excellent symptom relief was apparent in 16 of 21 (76.2%) laser-treated patients and in 12 of 16 (75%) nonlaser-treated patients. Follow-up bronchoscopy in 28 patients revealed tumor regression in 22 (79%). Median survival time was 16.3 weeks in the laser group and 11.7 weeks in the nonlaser group (P = 0.36). Longer median survival times were noted in laser-treated (22.8 weeks) and nonlaser-treated (16.4 weeks) patients receiving additional external beam treatments. Exsanguination occurred in 7 of 21 (33.3%) laser-treated patients and in 4 of 16 (25%) nonlaser-treated patients. The only factor affecting the exsanguination rate was implant location: 6 of 11 (54.5%) patients had lesions in the right or left upper lobe. EnBRT alone or with Nd:YAG laser resection provided good-to-excellent symptom palliation in these patients although a high rate of exsanguination occurred in both groups.