Lobe-sparing resection of multiple pulmonary metastases with a new 1318-nm Nd:YAG laser--first 100 patients

Laser pulmonary metastasectomy preserves parenchyma: a single-centre retrospective study from the United Kingdom

Background

Pulmonary metastasectomy (PME) is a modality increasingly employed to control oligometastatic disease from a variety of solid tumours.

We present data from a single UK centre, following the introduction of laser-assisted surgery (LAS) using the Limax® 120 Nd:Yag laser (Gebrüder Martin GmbH & Co. KG, Tuttlingen, Germany).

Methods

All patients undergoing PME between September 2015 and August 2018 were included in our study. Those undergoing LAS were compared to a control of conventional stapled wedge metastasectomy (SWM). Data was analysed retrospectively from a prospective kept database. Statistical analysis was performed using JASP (Version 0.14.1).

Results

Fifty-seven procedures in 46 patients, were included in the final analysis. Demographic data was similar at baseline between the LAS and SWM group, with colorectal cancer being the most common primary, 44/57 (77%). LAS was favoured in patients who had previously undergone pulmonary metastasectomy, 9/12 (75%). Patients in the LAS group had a smaller parenchymal volume resected (MD 30.6 cm3, p = 0.0084), with a lower incidence of clear histological marginal resection (11/27 vs 29/30, p < 0.0001); but no difference in operative time, morbidity, patient-reported outcome measures, or local recurrence between the two groups at 2 years. LAS was associated with a lower procedural cost (MD £452.92, p < 0.0001).

Conclusions

Laser-assisted pulmonary metastasectomy presents a safe and acceptable alternative to traditional stapled wedge resection, with notable parenchymal-sparing, no discernible learning curve, and lower direct costs.

Lung Metastases: Current Surgical Indications and New Perspectives

Pulmonary metastasectomy is an established treatment that can provide improved long- term survival for patients with metastatic tumor(s) in the lung. In this mini-review, we discuss the state of the art of thoracic surgery in surgical management of lung metastases which actually occurs for a large part of surgical activity in thoracic surgery department. We describe the principles of surgical therapy that have been defined across the time, and that should remain the milestones of lung metastases treatment: a radical surgery and an adequate lymphadenectomy. We then focus on current surgical indications and report the oncological results according to the surgical approach (open vs. mini-invasive), the histological type and number of lung metastases, and in case of re-metastasectomy. Finally, we conclude with a brief overview about the future perspectives in thoracic surgery in treatment of lung metastases.

The Evaluation of the 1318 nm Diode Laser in Open Liver Surgery

(1) Background: Numerous dissection instruments are available for liver resection. So far, there has been no evidence in favor of a specific dissection device effecting a reduction in postoperative mortality and morbidity or a reduction in intraoperative blood loss. The aim of the study was to evaluate the safety of liver resection with the 1318 nm surgical laser. (2) Methods: 151 consecutive patients who underwent liver resection using the 1318 nm surgical laser (n = 119) or conventional dissection methods (n = 32) were evaluated retrospectively. As primary outcome, postoperative complications were assessed using the Clavien–Dindo classification. Secondary outcomes were postoperative mortality, reoperations and reinterventions, intraoperative blood loss, the need for vascular control using the Pringle maneuver and oncological safety assessed through histopathological evaluation of resection margins. (3) Results: For liver resections using the 1318 nm surgical laser, the postoperative morbidity (41.2% vs. 59.4%, p = 0.066), mortality (1.7% vs. 3.1%, p = 0.513) and the reoperation rate (2.5% vs. 3.1%, p = 1.000) were not significantly different from conventional liver resections. In the laser group, a lower reintervention rate (9.2% vs. 21.9%, p = 0.050) was observed. The oncological safety demonstrated by a tumor-free resection margin was similar after laser and conventional resection (93.2% vs. 89.3%, p = 0.256). The median intraoperative blood loss was significantly lower in the laser group (300 mL vs. 500 mL, p = 0.005) and there was a significantly lower need for a Pringle maneuver (3.4% vs. 15.6%, p = 0.021). (4) Conclusions: Liver resections using the 1318 nm surgical laser can be routinely performed with a favorable risk profile. Compared to alternative resection methods, they are associated with low blood loss, appear adequate from an oncological point of view, and are not associated with increased mortality and morbidity.

Local Effects of a 1940 nm Thulium-Doped Fiber Laser and a 1470 nm Diode Laser on the Pulmonary Parenchyma: An Experimental Study in a Pig Model

The lungs are a common site of metastases from malignant tumors. Their removal with a minimal but safe tissue margin is essential for the long-term survival of patients. The aim of this study was to evaluate the usefulness of a 1940 nm thulium-doped fiber laser (TDFL) and a 1470 nm diode laser (DL) in a pig model of lung surgery that involved the incision and excision of lung tissue. Histopathological analysis was performed on days 0 and 7 after surgery. Neither TDFL nor DL caused significant perioperative or postoperative bleeding. Histological analysis revealed the presence of carbonized necrotic tissue, mixed fibrin-cellular exudate in the superficial zone of thermal damage and bands of deeper thermal changes. The mean total width of thermal damage on day 0 was 499.46 ± 61.44 and 937.39 ± 109.65 µm for TDFL and DL, respectively. On day 7, cell activation and repair processes were visible. The total width of thermal damage was 2615.74 ± 487.17 µm for TDFL vs. 6500.34 ±1118.02 µm for DL. The superficial zone of thermal damage was narrower for TDFL on both days 0 and 7. The results confirm the effectiveness of both types of laser in cutting and providing hemostasis in the lungs. TDFL caused less thermal damage to the lung parenchyma than DL.

Surgical Morbidity and Lung Function Changes After Laser-Assisted Pulmonary Metastasectomy: A Prospective Bicentric Study

Objective: The surgical resection of pulmonary metastases is associated with a survival benefit in selected patients. The use of laser devices for pulmonary metastasectomy (PM) is believed to facilitate the complete resection of metastases while preserving a maximum of healthy parenchyma. This is a prospective study to evaluate surgical outcome including the changes of lung function after laser–assisted surgery (LAS).

Methods: A total of 77 operations in 61 patients in which PM was carried out in a curative intent were analyzed. A 1.320 nm diode-pumped Nd: YAG-Laser was used for resection of the metastases. Surgical and clinical data were collected using a standardized form and postoperative lung function changes 3 and 6 months after surgery were assessed using whole body plethysmography and diffusion capacity for carbon monoxide (DLCO). Size and distance of metastases to the pleural surface were measured radiologically.

Results: A median of two metastases were resected per operation (range 1–13). The median duration of postoperative air leak was 1 day (range 0–11). LAS associated postoperative minor and major complications were observed in 4 (5%) cases and 1 (1%) case, respectively; there were no mortalities. The analysis of perioperative lung function showed that mean VC 3 months after surgery was reduced by 11 %, FEV1 by 11% and median DLCO by 11% (all p < 0.0001). There was almost no recovery of lung function between 3 and 6 months in the whole cohort. Patients with two or less metastases showed a recovery of lung function after 3 months regarding DLCO (p = 0.003). Decline of DLCO in the whole cohort correlated with the number of resected metastases at 3 months (r = 0.45, p = 0.006) and at 6 months (r = 0.42, p = 0.02) as well as depth of metastases in the parenchyma at 6 months (r = 0.48, p = 0.001).

Conclusions: LAS is a safe and effective method for PM even for higher numbers of metastases, with short duration of postoperative air leak and little morbidity. Number and depth, but not size of metastases affect lung function changes after resection.

Results of redo pulmonary metastasectomy

Repeat surgical resection (redo) for pulmonary metastases is a questionable, albeit intriguing topic. We performed an extensive review of the literature, to specifically analyze results of redo pulmonary metastasectomies. We reviewed a total of 3,523 papers. Among these, 2,019 were excluded for redundancy and 1,105 because they were not completely retrievable. Out of 399 eligible papers, 183 had missing information or missing abstract, while 96 lacked data on survival. A total of 120 papers dated from 1991 onwards were finally included. Data regarding mortality, major morbidity, prognostic factors and long-term survivals of the first redo pulmonary metastasectomies were retrieved and analyzed. Homogeneity of data was affected by the lack of guidelines for redo pulmonary metastasectomy and the risks of bias when comparing different studies has to be considered. According to the histology sub-types, redo metastasectomies papers were grouped as: colorectal (n=42), sarcomas (n=36), others (n=20) and all histologies (n=22); the total number of patients was 3,015. Data about chemotherapy were reported in half of the papers, whereas targeted or immunotherapy in 9. None of these associated therapies, except chemotherapy in two records, did significantly modify outcomes. Disease-free interval before the redo procedure was the prevailing prognostic factor and nearly all papers showed a significant correlation between patients’ comorbidities and prognosis. No perioperative mortality was reported, while perioperative major morbidity was overall quite low. Where available, overall survival after the first redo metastasectomy ranged from 10 to 72 months, with a 5-years survival of approximately 50%. The site of first recurrence after the redo procedure was mainly lung. Despite the data retrievable from literature are heterogeneous and confounding, we can state that redo lung metastasectomy is worthwhile when the lesions are resectable and the perioperative risk is low. At present, there are no “non-surgical” therapeutic options to replace redo pulmonary metastasectomies.

Local lung coagulation post resection: an ex-vivo porcine model

Following non-anatomical resection of lung parenchyma with a Nd:YAG laser, a coagulated surface remains. As ventilation starts, air leakage may occur in this area. The aim of the present study was to investigate, whether additional coagulation either before or after ventilation has an additional sealing effect. Freshly slaughtered porcine heart-lung blocks were prepared. The trachea was connected to a ventilator. Using a Nd:YAG laser (wavelength: 1320 nm, power: 60 W), round lesions (1.5 cm in diameter) with a depth of 1.5 cm were applied to the lung using an 800-μm laser fiber (5 s per lesion). Group 1 (n = 12) was control. Additional coagulation was performed in group 2 (n = 12) without and in group 3 (n = 12) with ventilation restarted. Air leakage (ml) from the lesions was measured. The thickness of each coagulation layer was determined on histological slices. Differences between individual groups were analyzed by one-way ANOVA (significance p < 0.05). After resection, 26.2 ± 2.7 ml of air emerged from the lesions per single respiration in group 1. Air loss in group 2 was 24.6 ± 2.5 ml (p = 0.07) and in group 3 23.7 ± 1.8 ml (p = 0.0098). In comparison to groups 1 and 2 thickness of the coagulation layers in group 3 was significantly increased. After non-anatomical porcine lung resection with a Nd:YAG laser, additional coagulation of the ventilated resection area can reduce air leakage.

Porcine skin damage thresholds and histological damage characteristics from 1319-nm laser radiation

There is an increasing use of near-infrared lasers in biomedical applications operating in the spectrum between 1300 and 1400 nm. To corroborate and expand the existing safety data for skin exposure to lasers in this wavelength region, the in-vivo ED50 damage thresholds were determined in Guizhou miniature pigs for 1319-nm laser radiation. Exposure durations of 0.4, 1.0, and 3.0 s and 1  /  e2 beam diameters of 0.98 and 1.96 cm were employed. Damage lesion determinations were performed at 1- and 24 h post exposure. The Bliss probit analysis was employed to establish the ED50 damage thresholds. Histopathological studies of skin damage were performed at 48 h after irradiation to reveal the damage characteristics. The skin damage thresholds at 1 h post exposure, given in peak radiant exposure, were 35.5, 36.1, and 37.1  J  /  cm2 at exposure durations of 0.4, 1.0, and 3.0 s with the spot diameter of 0.98 cm, and 28.6  J  /  cm2 at exposure duration of 3.0 s with the spot diameter of 1.96 cm. At 24 h post exposure, the ED50s increased slightly. Histologically, the thermal damage characteristics at the near-threshold level included gathering of the nuclear chromatin and cell vacuolation in the epidermis and deposition of blood cells in the capillary vessels. However, at the apparently above-threshold level, the damage characteristics included obvious stretching of the nuclear chromatin in the epidermis, closing of the capillary lumen, structural change of collagen fibers, and coagulative necrosis of the hair follicle cells. The damage induced by this laser could go deep into the fatty tissue. The obtained results may contribute to the knowledge base for the damage mechanisms and expand the database for the refinement of laser safety standards in the wavelength range of 1300 to 1400 nm.

Non-Ionizing Radiation in Swedish Health Care-Exposure and Safety Aspects

The main aim of the study was to identify and describe methods using non-ionizing radiation (NIR) such as electromagnetic fields (EMF) and optical radiation in Swedish health care. By examining anticipated exposure levels and by identifying possible health hazards we also aimed to recognize knowledge gaps in the field. NIR is mainly used in health care for diagnosis and therapy. Three applications were identified where acute effects cannot be ruled out: magnetic resonance imaging (MRI), transcranial magnetic stimulation (TMS) and electrosurgery. When using optical radiation, such as class 3 and 4 lasers for therapy or surgical procedures and ultra-violet light for therapy, acute effects such as unintentional burns, photo reactions, erythema and effects on the eyes need to be avoided. There is a need for more knowledge regarding long-term effects of MRI as well as on the combination of different NIR exposures. Based on literature and after consulting staff we conclude that the health care professionals' knowledge about the risks and safety measures should be improved and that there is a need for clear, evidence-based information from reliable sources, and it should be obvious to the user which source to address.

[Pulmonary metastases: classification and the need for staging?]

AIM

To analyze pulmonary metastases classifications which are used in Russian and foreign literature at present time.

MATERIAL AND METHODS

It is proposed the variant of pulmonary metastases staging depending on quantitative and regional prevalence of the process.

RESULTS

The development of pulmonary metastases classification is advisable to determine homogeneous subgroups of patients with metastatic lesion for prospective randomized trials in order to obtain objective results about the results of surgical or other local treatment of patients with intrapulmonary metastases.

Pulmonary metastasectomy in sarcoma-experiences with laser-assisted resection

Background

Previous data suggest a survival benefit in well selected patients with extrathoracic sarcoma after pulmonary metastasectomy. Different techniques have been described for pulmonary metastasectomy; however laser-assisted surgery (LAS) was suggested to provide the best outcome in patients with higher numbers of metastases.

Methods

Data were extracted from a prospectively maintained institutional database and a total of 83 patients who underwent pulmonary metastasectomy at our clinic in the last 11 years were identified.

Results

We analyzed a total of 106 operations of which LAS was performed in 46 and conventional resection in 60 cases. Significantly more metastases were resected in the LAS group compared to the conventional group [median, interquartile range (IQR): 6.5 (2.0-11.0) vs. 1.0 (1.0-3.5); P<0.0001]. Despite this difference the number of tumor recurrences was similar in both groups [64% tumor recurrences in the LAS group and 58% in the conventional group, odds ratio (OR) =1.3, P=0.6]. Furthermore, overall survival (OS) was comparable with a median survival of 77.6 and 29.0 months and 2- and 5-year survival rates of 71% and 63% as well as 53% and 36% in the respective cohorts [hazard ratio (HR) =0.74, P=0.43].

Conclusions

Using LAS a significantly higher number of metastases were removed while producing similar long-term results as compared to patients treated by other techniques. Expectably, recurrence rates in metastasized sarcoma patients remain high with either surgical method. Future studies will have to evaluate possible advantages provided by LAS in a prospective manner.

Comparison of the local effects of a 600-μm bare fibre at high laser power on lung parenchyma: Nd:YAG laser 1320 vs. 1064 nm

Lung metastases are often resected non-anatomically with a laser using a diode-pumped Nd:YAG laser at a wavelength of 1320 nm with a laser output of up to 60 W. Usually the removal of lesions is carried out in contact mode by means of a bare fibre. We compared the local effects of an Nd:YAG laser at a wavelength of 1064 nm with those at a wavelength of 1320 nm using a 600-μm bare fibre in contact mode in an experimental model. The investigations were carried out on porcine lungs freshly withdrawn at the abattoir. The 600-μm laser fibre was fixed vertically in contact with the lung surface on a fibre holder. The fibre holder was connected to a feeding device that advances the laser fibre at constant speeds (5, 10 or 20 mm/s). In each case, two laser powers were examined: 20 and 60 W. The lung lesions produced by the laser fibre were excised for histological examination. After haematoxylin-eosin staining, the depth of the vaporisation and coagulation zones (in μm) from the laser cuts was measured. For each setting, an average value was calculated. The individual groups were compared for significance using a non-parametric Mann-Whitney U test (p < 0.05). At a low speed of the bare fibre of 5 mm/s and a laser output of 20 W, the average depth of the vaporisation zone was 858 ± 3.3 μm (λ = 1064 nm) compared to 766.0 ± 7.5 μm (λ = 1320 nm) (p < 0.01). Upon faster movement (20 mm/s), the extension of the vaporisation zone decreased to 320.3 ± 7.1 μm (λ = 1064 nm). The depth of the vaporisation zone increased significantly at 60 W, both at λ = 1064 and 1320 nm with 1517.0 ± 1.7 μm and 1414.0 ± 4.9 μm, respectively. The extent of the coagulation zone was significantly smaller at 20 W and the low speed of 5 mm/s, namely, 200.4 ± 3.7 μm (λ = 1064 nm) and 224.1 ± 2.8 μm (1320-nm laser). Upon faster movement of the laser fibre at the same output, the extent of the coagulation zone decreased in both groups. At a laser power of 60 W, the extent of the coagulation zone was significantly less with the 1064-nm laser (110.3 ± 2.4 μm) than with the 1320-nm laser (324.8 ± 1.9 μm; p < 0.001). When the laser fibre moves more rapidly, the extent of the coagulation zone decreases further. The Nd:YAG laser with a wavelength of 1320 nm still has the optimal ratio of cutting and coagulation capacity on the resection surface. With the 1064-nm Nd:YAG laser, a higher cutting capacity is associated with a decrease of the coagulation capacity.

Pulmonary metastasectomy: outcomes and issues according to the type of surgical resection

According to a recent report by the Committee for Scientific Affairs of the Japanese Association for Thoracic Surgery, pulmonary metastasectomy accounted for as many as 10.2 % of all entry cases of general thoracic surgery, and its use is increasing year by year. Accordingly, many studies have examined the surgical procedures used during pulmonary metastasectomy for metastases from primary tumors affecting various organs as well as the outcomes of and indications for such procedures, but some problems remain. In this article, the following questions related to the surgical approach and the type of resection used during pulmonary metastasectomy are reviewed: (1) Wedge resection--what is a safe margin for preventing local recurrence? (2) What is the clinical significance of node sampling/dissection during pulmonary metastasectomy? and (3) When is segmentectomy necessary? In addition, we discuss: (4) open thoracotomy vs. video-assisted thoracoscopic surgery (VATS), (5) repeated metastasectomy for pulmonary metastases, (6) the surgical approach for bilateral pulmonary metastasectomy, (7) pneumonectomy, and (8) pulmonary metastasectomy combined with resection of the neighboring organs.

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Tissue effects resulting from eraser laser enucleation of the prostate: in vivo investigation

BACKGROUND/AIMS/OBJECTIVES: To describe the depth of the laser coagulation zone in vivo based on histological examinations and the functional outcome of a 1,318-nm diode laser for enucleation in benign prostatic enlargement (BPE).

METHODS

A total of 20 patients with BPE were treated by laser Eraser® enucleation of the prostate (ELEP). Prostatic tissue wedges were evaluated to assess the depth of the ELEP coagulation zones. Additionally, patients were assessed preoperatively and 12 months postoperatively.

RESULTS

The coagulation zones were 0.36 ± 0.17 mm in epithelial tissue, 0.28 ± 0.15 mm in stromal tissue, and 0.25 ± 0.12 mm in mixed tissue. The coagulation area at the cutting edge completely sealed capillary vessels, reaching a depth of 0.35 ± 0.15 mm. The diameter of the coagulated vessels measured 1.75 ± 0.83 mm. Mean blood loss was 115.54 ± 93.12 ml, catheter time 1.35 ± 0.33 days, and hospital stay 1.89 ± 0.52 days. The International Prostate Symptom Score, maximal flow rate, and quality of life significantly improved 12 months after the procedure.

CONCLUSIONS

ELEP is safe and effective for BPE treatment and yields good results at a follow-up of 1 year. Because of the limited penetration depth, damage to the urinary sphincter is not expected.

Advances in microscopy and complementary imaging techniques to assess the fate of drugs ex vivo in respiratory drug delivery: an invited paper

The technical advances in microscopy imaging techniques have been applied to assess the fate of drugs for researching respiratory drug delivery in ex vivo and in vivo experiments. Recent developments in optical imaging (confocal microscopy, multi-photon microscopy, fluorescence imaging (FLI) and bioluminescence imaging (BLI)), and in non-optical imaging (magnetic resonance imaging (MRI), computing tomography (CT), positron-emission tomography (PET) and single-photon-emission computed tomography (SPECT)) are presented with their derivative medical devices. Novel microscopy have been utilized to address many biological questions in basic research and are becoming powerful clinical tools for non-invasive objective diagnosis, guided treatment, and monitoring therapies. The goal of this paper is to present recent advances in microscopy imaging techniques and to discuss their novel applications in respiratory drug delivery imaging.

Is surgery for multiple lung metastases reasonable? A total of 328 consecutive patients with multiple-laser metastasectomies with a new 1318-nm Nd:YAG laser

OBJECTIVE

Our objective was to define the role of a new 1318-nm Nd:YAG laser for lobe- and parenchyma-saving resection of multiple lung metastases.

PATIENTS AND METHODS

From January 1996 to December 2003, a total of 3267 nodules (10/patient) were removed from 328 patients (164 men/164 women, mean age 61 years). Criteria for eligibility were expanded to any primary tumors with no upper limit of metastases given. All parenchymal resections were performed with a new 1318-nm Nd:YAG laser whose effect on lung tissue differs significantly from that of the 1064-nm wavelength owing to a 10-fold higher absorption in water and one-third extinction in blood. In 93%, precision laser resection was achieved. The lobectomy rate was only 7%.

RESULTS

Pathologic examination revealed 2546 metastases (8/patient) and lymph node disease in 19%. Complete resections (R0) were achieved in 93% of 177 patients undergoing unilateral procedures with a mean of 3 metastases (range 1%-29%) and 75% of 151 patients having bilateral operations with a mean of 13 metastases (range 2-124). The 5-year survival after R0 was 55% for solitary nodules, 41% for all patients, 28% for 10 metastases, and 26% for 20 or more metastases resected. Outcome was significantly poorer after incomplete resection (7%). No 30-day mortality was observed. Major postoperative complications included prolonged air leaks (n = 2), intrapleural bleeding (n = 2), and late pneumothorax (n = 2); all were treated successfully with a chest tube.

CONCLUSION

This new 1318-nm Nd:YAG laser facilitates complete resection of multiple bilateral centrally located metastases and thus is lobe sparing. Resection of 20 or more metastases is reasonable because long-term survival was significantly better than that observed with incomplete resection.

Laser resection technique and results of multiple lung metastasectomies using a new 1,318 nm Nd:YAG laser system

BACKGROUND AND OBJECTIVES

Advantages of a new 1,318 nm Nd:YAG laser based on multiple lung metastasectomies are shown.

STUDY DESIGN/MATERIALS AND METHODS

Ninety-three percent of 328 patients with metastases (8/patient, range 1-124) had precision laser resections (lobectomy-rate reduced to 7%); this laser delivers 20 kW/cm(2) 1,318 nm power densities with 400 microm fibers, and a focussing handpiece. Absorption in water is tenfold higher.

RESULTS AND CONCLUSIONS

Between 1/1996 and 12/2003 in 328 patients (164 males/females, 61 years) 3,267 nodules were removed. Pathologic examination revealed 2,546 metastases (range 3-80 mm) from kidney (n = 112), colorectal (n = 91), and breast cancers (n = 35). In 85% of patients where the complete resection was achieved the 5-year survival was 41%. For remaining 15% (incomplete resection) the 5-year survival was 7%. Five-year survival for patients with 10 (and more) metastases was 28%, for patients with 20 (and more) was 26%. No 30-day mortality was observed.

CONCLUSION

This new laser system facilitates any kind of parenchymal lung resection in lobe-sparing manner and in case of complete resection improves significantly the survival.

A proposed diagnostic approach to the patient with the subcentimeter pulmonary nodule: techniques that facilitate video-assisted thoracic surgery excision

This article describes a diagnostic approach to the management of subcentimeter pulmonary nodules and delineates the contribution the chest surgeon brings to clinical decision making. This includes clinical experience and knowledge of nodule accessibility to thoracoscopic excisional biopsy based on the anticipated localization technique to be used. Characteristics of the ideal localization technique are discussed. Different localization techniques are then described, and their respective advantages and disadvantages are discussed. These techniques include intraoperative finger and instrument localization, preoperative radiologically placed hooks and coils, intraoperative ultrasonography, and preoperative placement of radiotracer markers.

Laser resection of lung metastasis

Presentation of the laser resection technique for metastatic lung diseases: a new Nd:YAG 1.318 nm wavelength laser system enables the thoracic surgeon to extend indication and include a larger number of patients for pulmonary metastasectomy. This parenchyma-saving technique allows removal of a significantly higher number of lung nodules in comparison to conventional techniques (stapler, clamp resection). The novel laser system consisted of a high performance Nd:YAG laser emitting the 1318 nm wavelength exclusively up to a power of 40 W, thin flexible quartz fibers (400 μm) with low water content and a four-lens focusing handpiece. Description of laser system, the technique of laser resection, together with an overview of the literature is presented.

Principles of Lasers and Biophotonic Effects

In this review, we discuss how, due to a variety of different interactions between laser radiation and biological tissue, the laser has become an established instrument in most medical fields. Depending on the interaction time and the effective power density, three types of laser tissue interaction can be distinguished: photochemical effects, photothermal effects, and photomechanical and photoionizing effects. After a description of the physical mechanisms, the typical parameters, and the medical applications of these effects, a review of the laser types used in medicine is given. For percutaneous laser disc decompression (PLDD), lasers in the near-infrared region (Nd:YAG, Ho:YAG, and diode lasers) and with visible green radiation (frequency doubled Nd:YAG, called "KTP laser") were reported to be effective.