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BMJ Open May 2022Endovenous microwave ablation (EMA) is a relatively novel thermal ablation treatment for great saphenous vein (GSV) varicosis, and its efficacy and safety are rarely...
Efficacy and safety of endovenous microwave ablation versus laser ablation for great saphenous vein varicosis: study protocol for a multicentre, randomised controlled non-inferiority trial.
INTRODUCTION
Endovenous microwave ablation (EMA) is a relatively novel thermal ablation treatment for great saphenous vein (GSV) varicosis, and its efficacy and safety are rarely reported. This study aims to explore whether EMA can be comparable to endovenous laser ablation (EVLA), which is a widely used thermal ablation treatment in clinical practice.
METHODS AND ANALYSIS
This is a multicentre, randomised controlled non-inferiority trial to compare the efficacy and safety of EMA and EVLA in patients with GSV varicosis. We will recruit 180 patients in 6 centres and randomly assign them into treatment group (EMA group) and control group (EVLA group) in a 1:1 ratio. The patients will return to the hospitals at 7 days, 3 months, 6 months and 12 months, and will be called at 1 month after the treatment for follow-up visits. The primary outcome is the occlusion rate of GSV immediately, at 6 months, and at 12 months after the treatment. The secondary outcomes are Venous Clinical Severity Score (VCSS), Aberdeen Varicose Vein Questionnaire (AVVQ) Score, operation time and instrument performance evaluation.
ETHICS AND DISSEMINATION
This protocol has been approved by the Clinical Trial Ethics Committee of Beijing Hospital (2020BJYYEC-126-02), Peking Union Medical College Hospital (KS2020393), Beijing Tsinghua Changgung Hospital (No.20279-2-02), Beijing Luhe Hospital.Capital Medical University (2020-LHYW-030-01), the First Hospital of Hebei Medical University (No.2020249), and the First Affiliated Hospital of Xi'an Jiaotong University (XJTU1AF2021LSY-12). The trial results will be published in peer-reviewed journals.
TRIAL REGISTRATION NUMBER
NCT04726124.
Topics: Endovascular Procedures; Equivalence Trials as Topic; Humans; Laser Therapy; Microwaves; Multicenter Studies as Topic; Neoplasm Recurrence, Local; Randomized Controlled Trials as Topic; Saphenous Vein; Treatment Outcome; Varicose Veins
PubMed: 35613801
DOI: 10.1136/bmjopen-2021-059213 -
Advanced Science (Weinheim,... Jul 2022Ablation of materials in combination with element-specific analysis of the matter released is a widely used method to accurately determine a material's chemical...
Ablation of materials in combination with element-specific analysis of the matter released is a widely used method to accurately determine a material's chemical composition. Among other methods, repetitive ablation using femto-second pulsed laser systems provides excellent spatial resolution through its incremental removal of nanometer thick layers. The method can be combined with high-resolution mass spectrometry, for example, laser ablation ionization mass spectrometry, to simultaneously analyze chemically the material released. With increasing depth of the volume ablated, however, secondary effects start to play an important role and the ablation geometry deviates substantially from the desired cylindrical shape. Consequently, primarily conical but sometimes even more complex, rather than cylindrical, craters are created. Their dimensions need to be analyzed to enable a direct correlation with the element-specific analytical signals. Here, a post-ablation analysis method is presented that combines generic polydimethylsiloxane-based molding of craters with the volumetric reconstruction of the crater's inverse using X-ray computed tomography. Automated analysis yields the full, sub-micron accurate anatomy of the craters, thereby a scalable and generic method to better understand the fundamentals underlying ablation processes applicable to a wide range of materials. Furthermore, it may serve toward a more accurate determination of heterogeneous material's composition for a variety of applications without requiring time- and labor-intensive analyses of individual craters.
Topics: Laser Therapy; Lasers; Mass Spectrometry; Tomography, X-Ray Computed
PubMed: 35521972
DOI: 10.1002/advs.202200136 -
Cancer Imaging : the Official... Oct 2019MRI-guided laser interstitial thermal therapy (LITT) is the selective ablation of a lesion or a tissue using heat emitted from a laser device. LITT is considered a less... (Review)
Review
MRI-guided laser interstitial thermal therapy (LITT) is the selective ablation of a lesion or a tissue using heat emitted from a laser device. LITT is considered a less invasive technique compared to open surgery that provides a nonsurgical solution for patients who cannot tolerate surgery. Although laser ablation has been used to treat brain lesions for decades, recent advances in MRI have improved lesion targeting and enabled real-time accurate monitoring of the thermal ablation process. These advances have led to a plethora of research involving the technique, safety, and potential applications of LITT.LITT is a minimally invasive treatment modality that shows promising results and is associated with decreased morbidity. It has various applications, such as treatment of glioma, brain metastases, radiation necrosis, and epilepsy. It can provide a safer alternative treatment option for patients in whom the lesion is not accessible by surgery, who are not surgical candidates, or in whom other standard treatment options have failed. Our aim is to review the current literature on LITT and provide a descriptive review of the technique, imaging findings, and clinical applications for neurosurgery.
Topics: Brain Neoplasms; Glioma; Humans; Laser Therapy; Magnetic Resonance Imaging; Neuronavigation
PubMed: 31615562
DOI: 10.1186/s40644-019-0250-4 -
PloS One 2018Single-fiber laser treatment of the prostate has been widely accepted in the clinic due to its minimal invasiveness and high controllability. However, for large tumors,...
Single-fiber laser treatment of the prostate has been widely accepted in the clinic due to its minimal invasiveness and high controllability. However, for large tumors, multiple insertions of the laser probe would be needed to achieve full coverage of the tumor, increasing the complexity of the treatment and occasionally resulting in the incomplete killing of tumor cells due to a mismatch between the planned insertion location and the actual probe insertion location. Treatment with a dual-fiber laser results in greater lesion coverage following a single insertion of the probe, with the lesion coverage being even greater than the sum of the coverage of two sequential insertion of a single-fiber laser probe, potentially reducing treatment time and clinical complications. Both theoretical and experimental analyses have been performed to evaluate the proposed dual-fiber laser treatment. A finite element model was established to simulate the treatment process. The simulation results indicated that there is a clear difference between the ablation coverage created using dual-fiber laser ablation and that created using the superposition of sequential single-fiber laser ablation. In addition, the coverage is dependent on the spacing distance between the two fibers. Both ex vivo and in vivo canine prostate tissues were treated by dual-fiber laser ablation, with lesions analyzed by magnetic resonance imaging (MRI), ultrasound imaging, and pathology. The results demonstrate that dual-fiber laser ablation can markedly increase the range of the ablation zone when compared with single-fiber modes. The safety and feasibility of dual-fiber laser treatment has been confirmed, and a treatment plan using dual-fiber laser ablation has also been proposed.
Topics: Animals; Computer Simulation; Dogs; Humans; Laser Therapy; Male; Models, Biological; Prostatic Neoplasms; Temperature
PubMed: 30356335
DOI: 10.1371/journal.pone.0206065 -
International Journal of Hyperthermia :... 2020To determine the clinical efficacy of laser ablation for the tredatment of primary hyperparathyroidism (pHPT). Twelve patients with pHPT were treated with laser...
To determine the clinical efficacy of laser ablation for the tredatment of primary hyperparathyroidism (pHPT). Twelve patients with pHPT were treated with laser ablation. Energy was administered by means of 1.5 m optical fibers percutaneously placed into the target 21 G needles. A laser ablation unit (EchoLaser X4, Esaote) applied 3 W power for 400-600 s/fiber/insertion to a total 3600-9000 Joules of energy. Patient serum parathyroid hormone (PTH) and calcium levels were checked at baseline and thereafter every 6 months. Patients were followed-up for 2 years with serologic and contrast-enhanced ultrasound. Therapeutic success was defined as normal PTH and calcium levels together with disappearance of nodule-related symptoms. All procedures were performed in single session. Immediately following ablation, contrast enhanced ultrasound confirmed that all but one target had become avascular (technical success rate 11/12; 92%), remaining avascular at all follow-up ultrasound examinations, thereafter. The mean volume of parathyroid nodules decreased from 0.54 cc to 0.36 cc (72.0%). Serum PTH and calcium levels were significantly lower at 1, 12 and 24 m compared to baseline ( < 0.01). By 6 m, PTH and calcium returned to normal and were stable until 24 m in all successfully treated patients. All cases of hyperparathyroid-related symptoms resolved by 6 m (ostealgia [ = 5], repeated renal colic [ = 5], vomiting [ = 3]). Only one patient (8%) reported transient dysphonia as a minor complication. Laser ablation of enlarged, symptomatic parathyroid glands is safe and well-tolerated and can produce long-term, sustained reduction of serum PTH and calcium levels.
Topics: Adenoma; Adult; Aged; Aged, 80 and over; Female; Humans; Laser Therapy; Male; Middle Aged; Parathyroid Neoplasms; Ultrasonography
PubMed: 32308070
DOI: 10.1080/02656736.2020.1750712 -
The Cochrane Database of Systematic... Dec 2013Cervical intraepithelial neoplasia (CIN) is the most common pre-malignant lesion. Atypical squamous changes occur in the transformation zone of the cervix with mild,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cervical intraepithelial neoplasia (CIN) is the most common pre-malignant lesion. Atypical squamous changes occur in the transformation zone of the cervix with mild, moderate or severe changes described by their depth (CIN 1, 2 or 3). Cervical intraepithelial neoplasia is treated by local ablation or lower morbidity excision techniques. Choice of treatment depends on the grade and extent of the disease.
OBJECTIVES
To assess the effectiveness and safety of alternative surgical treatments for CIN.
SEARCH METHODS
We searched the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE and EMBASE (up to November 2012). We also searched registers of clinical trials, abstracts of scientific meetings and reference lists of included studies.
SELECTION CRITERIA
Randomised controlled trials (RCTs) of alternative surgical treatments in women with cervical intraepithelial neoplasia.
DATA COLLECTION AND ANALYSIS
Two review authors independently abstracted data and assessed risks of bias. Risk ratios that compared residual disease after the follow-up examination and adverse events in women who received one of either laser ablation, laser conisation, large loop excision of the transformation zone (LLETZ), knife conisation or cryotherapy were pooled in random-effects model meta-analyses.
MAIN RESULTS
Twenty-nine trials were included. Seven surgical techniques were tested in various comparisons. No significant differences in treatment failures were demonstrated in terms of persistent disease after treatment. Large loop excision of the transformation zone appeared to provide the most reliable specimens for histology with the least morbidity. Morbidity was lower than with laser conisation, although the trials did not provide data for every outcome measure. There were not enough data to assess the effect on morbidity when compared with laser ablation.
AUTHORS' CONCLUSIONS
The evidence suggests that there is no obvious superior surgical technique for treating cervical intraepithelial neoplasia in terms of treatment failures or operative morbidity.
Topics: Conization; Cryosurgery; Female; Humans; Laser Therapy; Uterine Cervical Neoplasms; Uterine Cervical Dysplasia
PubMed: 24302546
DOI: 10.1002/14651858.CD001318.pub3 -
Photoselective laser ablation of the prostate: a review of the current 2015 tissue ablation options.The Canadian Journal of Urology Oct 2015Transurethral resection of the prostate (TURP) is still considered the gold standard to treat benign prostatic hyperplasia (BPH). However, photoselective vaporization of... (Comparative Study)
Comparative Study Review
INTRODUCTION
Transurethral resection of the prostate (TURP) is still considered the gold standard to treat benign prostatic hyperplasia (BPH). However, photoselective vaporization of the prostate (PVP) has gained widespread acceptance as an alternative option requiring preoperative patient selection. Four laser systems are currently in use: holmium, thulium, diode and GreenLight.
MATERIALS AND METHODS
The goal of this article is to review the physics and the basics behind laser prostatectomies, as well as to present the most current literature concerning the results, advantages, disadvantages and international recommendations for each vaporization procedure.
RESULTS
Holmium laser ablation of the prostate (HoLAP) and GreenLight photoselective vaporization of the prostate are an alternative to TURP for small to medium-sized prostates, providing equivalent efficacy and safety. GreenLight is also safe and effective in large-sized prostates and especially beneficial in anti-coagulated individuals compared to TURP. Thulium vaporization of the prostate (ThuVAP) and diode vaporization both require additional randomized trials and long term studies before conclusion is made, despite promising initial results. Diode vaporization provides the best hemostasis overall, but at the cost of increased complication and re-treatment rate, and thus is not recommended except in severely anti-coagulated patients.
CONCLUSION
Laser vaporization is a safe and effective alternative to TURP in the treatment of benign prostatic hyperplasia (BPH) for carefully selected patients. However, further research is still needed to assess the durability of each technology.
Topics: Aged; Aged, 80 and over; Blood Loss, Surgical; Follow-Up Studies; Humans; Laser Therapy; Lasers, Solid-State; Male; Minimally Invasive Surgical Procedures; Operative Time; Practice Guidelines as Topic; Prostatic Hyperplasia; Randomized Controlled Trials as Topic; Risk Assessment; Severity of Illness Index; Treatment Outcome; Volatilization
PubMed: 26497343
DOI: No ID Found -
Analytica Chimica Acta Nov 2021Deep-ultraviolet laser ablation with a pulsed 193 nm ArF excimer laser was used to remove localized regions from tissue sections from which proteins were extracted for...
Deep-ultraviolet laser ablation with a pulsed 193 nm ArF excimer laser was used to remove localized regions from tissue sections from which proteins were extracted for spatially resolved proteomic analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS). The ability to capture intact proteins by ablation at 193 nm wavelength was verified by matrix-assisted laser desorption ionization (MALDI) of the protein standard bovine serum albumin (BSA), which showed that BSA was ablated and captured without fragmentation. A Bradford assay of the ablated and captured proteins indicated 90% efficiency for transfer of the intact protein at a laser fluence of 3 kJ/m. Rat brain tissue sections mounted on quartz microscope slides and ablated in transmission mode yielded 2 μg protein per mm as quantified by the Bradford assay. Tissue areas ranging from 0.06 mm to 1 mm were ablated and the ejected material was collected for proteomic analysis. Extracted proteins were digested and the resulting peptides were analyzed by LC-MS/MS. The proteins extracted from the ablated areas were identified and the average number of identified proteins ranged from 85 in the 0.06 mm area to 2400 in the 1 mm area of a 50 μm thick tissue. In comparison to infrared laser ablation of equivalent sampled areas, both the protein mass and number of proteins identified using DUV laser ablation sampling were approximately four times larger.
Topics: Animals; Cattle; Chromatography, Liquid; Infrared Rays; Laser Therapy; Proteomics; Rats; Serum Albumin, Bovine; Tandem Mass Spectrometry
PubMed: 34625253
DOI: 10.1016/j.aca.2021.339021 -
IEEE Transactions on Bio-medical... Aug 2022Focal laser ablation is a minimally invasive method of treating cancerous lesions in organs such as prostate, liver and brain. Oncologic control is achieved by inducing...
Focal laser ablation is a minimally invasive method of treating cancerous lesions in organs such as prostate, liver and brain. Oncologic control is achieved by inducing hyperthermia throughout the target while minimizing damage to surrounding tissue. Consequently, successful clinical outcomes are contingent upon achieving desired ablation volumes. Magnetic resonance thermometry is frequently used to monitor the formation of the induced thermal damage zone and inform the decision to terminate energy delivery. However, due to the associated cost and complexity there is growing interest in the development of alternative approaches. Here we investigate the utility of real-time interstitial interrogation of laser-tissue interaction as an inexpensive alternative monitoring modality that provides direct assessment of tissue coagulation without the need for organ specific calibration. The optical contrast mechanism was determined using a Monte Carlo model. Subsequently, four interstitial probe designs were manufactured and assessed in a tissue mimicking phantom under simultaneous magnetic resonance imaging. Finally, the optimal probe design was evaluated in ex vivo bovine muscle. It was found to be capable of providing sufficient feedback to achieve pre-defined ablation radii in the range 4-7 mm with a mean absolute error of 0.3 mm. This approach provides an inexpensive monitoring modality that may facilitate widespread adoption of focal laser ablation.
Topics: Animals; Cattle; Laser Therapy; Magnetic Resonance Imaging; Male; Phantoms, Imaging; Prostate; Thermometry
PubMed: 35148260
DOI: 10.1109/TBME.2022.3150279 -
STAR Protocols Jun 2022This protocol describes the preparation of pupae for laser ablation and live imaging of the notum (dorsal thorax). Because the pupa is stationary, it can be...
This protocol describes the preparation of pupae for laser ablation and live imaging of the notum (dorsal thorax). Because the pupa is stationary, it can be continuously live imaged for multiple days if desired, making it ideal for studying wound signaling and repair, from before laser ablation through wound closure. In this protocol, we demonstrate the processes of staging, partially dissecting, mounting, wounding, and live imaging the pupal notum, with the wounding occurring during the live imaging process. For complete details on the use and execution of this protocol, please refer to O'Connor et al. (2021b).
Topics: Animals; Drosophila; Drosophila melanogaster; Laser Therapy; Pupa; Thorax
PubMed: 35600923
DOI: 10.1016/j.xpro.2022.101396