We systematically assessed the learning curve of Holmium laser enucleation of the prostate using the available literature to identify, as our primary outcome, the average number of cases required to ...reach competency. A computerized search of PubMed and Scopus for articles published from inception through to January 2018 was performed including 24 studies with a total of 5173 patients. Even though different outcome measures require varying case-loads to reach a plateau, Holmium laser enucleation of prostate has an acceptable learning curve with a proposed figure approximating 25-50 cases, with a structured mentorship programme aiding for faster progress.
Transurethral resection of prostate (TURP) still remains the “gold standard” surgical treatment for benign prostatic hyperplasia (BPH). In recent years, holmium laser enucleation of prostate (HoLEP) ...gets more and more popularity in the world. Our objective is to compare the efficacy and safety of HoLEP and TURP for BPH. Eleven studies met our eligibility criteria including 1339 patients. The prostate sizes of the all included studies were smaller than 100 g. Overall, in patients with small to mid-sized prostates, HoLEP offers safer clinical outcomes with less blood drop and potentially better long-term relief of bladder outlet obstruction.
Abstract Background The GOLIATH study is a 2-yr trial comparing transurethral resection of prostate (TURP) to photoselective vaporization with the GreenLight XPS Laser System (GL-XPS) for the ...treatment of benign prostatic obstruction (BPO). Noninferiority of GL-XPS to TURP was demonstrated based on a 6-mo follow-up from the study. Objective To determine whether treatment effects observed at 6 mo between GL-XPS and TURP was maintained at the 2-yr follow-up. Design, setting, and participants Prospective randomized controlled trial at 29 centers in nine European countries involving 281 patients with BPO. Intervention Photoselective vaporization using the 180-W GreenLight GL-XPS or conventional (monopolar or bipolar) TURP. Outcome measurements and statistical analysis The primary outcome was the International Prostate Symptom Score for which a margin of three was used to evaluate the noninferiority of GL-XPS. Secondary outcomes included Qmax , prostate volume, prostate specific antigen, Overactive Bladder Questionnaire Short Form, International Consultation on Incontinence Questionnaire Short Form, occurrence of surgical retreatment, and freedom from complications. Results and limitations One hundred and thirty-six patients were treated using GL-XPS and 133 using TURP. Noninferiority of GL-XPS on International Prostate Symptom Score, Qmax , and freedom from complications was demonstrated at 6-mo and was sustained at 2-yr. The proportion of patients complication-free through 24-mo was 83.6% GL-XPS versus 78.9% TURP. Reductions in prostate volume and prostate specific antigen were similar in both arms and sustained over the course of the trial. Compared with the 1st yr of the study, very few adverse events or retreatments were reported in either arm. Treatment differences in the Overactive Bladder Questionnaire Short Form observed at 12-mo were not statistically significant at 24-mo. A limitation was that patients and treating physicians were not blinded to the therapy. Conclusions Twenty-four-mo follow-up data demonstrated that GL-XPS provides a durable surgical option for the treatment of BPO that exhibits efficacy and safety outcomes similar to TURP. Patient summary The long-term effectiveness and safety of GLP-XLS was similar to conventional TURP for the treatment of prostate enlargement.
Fractional laser technology is routinely used in the treatment of acne scarring, with thermal injury resulting in collagen synthesis and remodeling. Use of a picosecond pulse duration with a ...diffractive lens array may be a new technologic advancement in the treatment of acne scarring.
To investigate the safety and efficacy of a 755-nm alexandrite picosecond pulse duration laser with diffractive lens array for the treatment of facial acne scarring.
This single-center, prospective study performed in a private practice with a dedicated research department included patients with clinically diagnosed scarring secondary to inflammatory or cystic acne.
Patients received 6 treatments with a 755-nm picosecond laser with a spot size of 6 mm, fluence of 0.71 J/cm2, repetition rate of 5 Hz, and pulse width of 750 picoseconds in combination with a diffractive lens array, allowing for greater surface area and pattern density per pulse.
The pain and satisfaction scores for overall appearance and texture were recorded. Masked assessment of clinical photographs and analysis of 3-dimensional volumetric data were performed. Biopsy specimens were obtained for independent histologic evaluation by 2 investigators at baseline and at 3 months after last treatment.
Fifteen women and 5 men (mean age, 44 years; age range, 27-61 years) with Fitzpatrick skin types I through V and facial acne scarring were enrolled. The mean pain score was 2.83 of 10. Patients were satisfied to extremely satisfied with improvement in appearance and texture at their final treatment and follow-up visits. The masked assessment scores of 17 patients were 1.5 of 3 and 1.4 of 3 at 1 and 3 months, respectively (a score of 0 indicates 0%-25% improvement and a score of 3 indicates >75% improvement). A 3-dimensional analysis revealed a mean 24.3% improvement in scar volume, maintained at 1 (24.0%) and 3 (27.2%) months after treatment. Histologic analysis revealed elongation and increased density of elastic fibers, with an increase in dermal collagen and mucin.
Treatment of facial acne scars with a diffractive lens array and 755-nm picosecond laser produced improvement in appearance and texture at 3 months after the last treatment, with objective findings similar to those published for a series of fractional ablative laser treatments. Histologic findings suggest that improvement in scarring from this treatment goes beyond remodeling of collagen.
Lasers for stone treatment: how safe are they? Noureldin, Yasser A; Kallidonis, Panagiotis; Liatsikos, Evangelos N
Current opinion in urology,
03/2020, Letnik:
30, Številka:
2
Journal Article
To update laser lithotripsy advances in regard to new laser types and technologies as well as review contemporary laser safety concerns.
The high prevalence of urolithiasis and the continuing ...miniaturization of scopes has encouraged the growth of laser lithotripsy technology. The holmium:yttrium-aluminum-garnet (Ho:YAG) laser has been used for over 20 years in endourology and has been extensively studied. Holmium laser power output is affected by a number of factors, including pulse energy, pulse frequency, and pulse width. Several recent experimental studies suggest that the new dual-phase Moses 'pulse modulation' technology, introduced in high-power laser machines, carries a potential to increase stone ablation efficiency and decrease stone retropulsion. A newly introduced thulium fiber laser (TFL) has been adapted to a very small laser fiber size and is able to generate very low pulse energy and very high pulse frequency. Both of these technologies promise to play a larger role in laser lithotripsy in the near future. However, more experimental and clinical studies are needed to expand on these early experimental findings. Even though laser lithotripsy is considered safe, precautions should be taken to avoid harmful or even catastrophic adverse events to the patient or the operating room staff.
The Ho:YAG laser remains the clinical gold standard for laser lithotripsy for over the last two decades. High-power Ho:YAG laser machines with Moses technology have the potential to decrease stone retropulsion and enhance efficiency of laser ablation. The new TFL has a potential to compete with and perhaps even replace the Ho:YAG laser for laser lithotripsy. Safety precautions should be taken into consideration during laser lithotripsy.
A diode-pumped, actively mode-locked high-power thulium (Tm
)-doped double-clad silica fiber laser is demonstrated, providing an average output power in mode-locked (continuous wave) operation of 53 ...W (72 W) with a slope efficiency of 34% (38%). Mode-locking in the 6th-harmonic order was obtained by an acousto-optic modulator driven at 66 MHz without dispersion compensation. The shortest measured output pulse width was 200 ps. Owing to a diffraction grating as cavity end mirror, the central wavelength could be tuned from 1.95 to 2.13 μm. The measured beam quality in mode-locked and continuous wave operation has been close to the diffraction limit.
Application of a multilayer Molybdenum Disulfide (MoS2) thin film as a saturable absorber was experimentally demonstrated by realizing a stable and robust passive mode-locked fiber laser via the ...evanescent field interaction between the light and the film. The MoS2 film was grown by chemical vapor deposition, and was then transferred to a side polished fiber by a lift-off method. Intensity-dependent optical transmission through the MoS2 thin film on side polished fiber was experimentally observed showing efficient saturable absorption characteristics. Using erbium doped fiber as an optical gain medium, we built an all-fiber ring cavity, where the MoS2 film on the side polished fiber was inserted as a saturable absorber. Stable dissipative soliton pulse trains were successfully generated in the normal dispersion regime with a spectral bandwidth of 23.2 nm and the pulse width of 4.98 ps. By adjusting the total dispersion in the cavity, we also obtained soliton pulses with a width of 637 fs in the anomalous dispersion regime near the lasing wavelength λ = 1.55 μm. Detailed and systematic experimental comparisons were made for stable mode locking of an all-fiber laser cavity in both the normal and anomalous regimes.
In this work we demonstrate comprehensive studies on graphene oxide (GO) and reduced graphene oxide (rGO) based saturable absorbers (SA) for mode-locking of Er-doped fiber lasers. The paper describes ...the fabrication process of both saturable absorbers and detailed comparison of their parameters. Our results show, that there is no significant difference in the laser performance between the investigated SA. Both provided stable, mode-locked operation with sub-400 fs soliton pulses and more than 9 nm optical bandwidth at 1560 nm center wavelength. It has been shown that GO might be successfully used as an efficient SA without the need of its reduction to rGO. Taking into account simpler manufacturing technology and the possibility of mass production, GO seems to be a good candidate as a cost-effective material for saturable absorbers for Er-doped fiber lasers.
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