A Case of Refractory Childhood Glaucoma Secondary to Weill-Marchesani Syndrome:Management with Combined CO_(2) Laser-Assisted Sclerectomy Surgery and Trabeculectomy

A 2-year-old girl was diagnosed as Weill-Marchesani syndrome with typical systemic features of short stature,short and stubby hands and feet,language disorders and mental retardation.He developed bilateral angle closure glaucoma,ectopia lentis and suffered visual loss from the ocular features of Weill-Marchesani syndrome.The child was successfully treated by combined CO_(2) laser-assisted sclerectomy surgery and trabeculectomy.

A Combination of Endoscopic CO₂Laser Microsurgery and Radiotherapy for Treatment of T2N0M0 Glottic Carcinoma

The aims of this study were to evaluate the results of CO2 laser surgery alone and CO2 laser surgery combined with radiotherapy in patients with T2N0M0 glottic carcinoma. A retrospective analysis was conducted of 35 cases of T2N0M0 glottic carcinoma. Fourteen patients with normal vocal cord mobility were treated with endoscopic CO2 laser surgery alone. The remaining 21 patients were treated with CO2 laser surgery followed by radiotherapy (44 - 70 Gy, including low-dose carboplatin chemoradiotherapy). Main outcome measures were local control, organ preservation, recurrence, 5-year survival, and successful salvage in cases of recurrence. We evaluated the patient’s voice with the psychoacoustics GRBAS scale, maximum phonation time (MPT), and airflow rate (AFR) obtained by aerodynamic tests. Mean follow-up period was 5 years. Among the 35 T2N0M0 patients, 5-year survival and 5-year voice preservation rates were 97% and 89%, respectively. Local recurrence occurred in 7 of these patients (20%);4 of 7 local recurrences were successfully re-treated by laser surgery. Total laryngectomy was necessary for salvage treatment in the remaining 3 patients. The post-treatment voice qualities were judged to be the same or improved over pretreatment qualities. There was little change in MPT and AFR after treatment in non-recurrence patients. CO2 laser microsurgery is an excellent tool for treating selected cases of T2N0M0

In vitro comparison of the vaporesection of human benign prostatic hyperplasia using 70-and 120-W 2μm lasers

The purpose of the current ex vivo study was to compare the speed of vaporesection of human prostatic tissue with benign prostatic hyperplasia （BPH） and the depth of tissue damage using 70- and 120-W 2-tim laser devices. Fresh prostatic tissue specimens were obtained from five patients by open prostatectomy, and were divided into separate groups （70 and 120 W） based on the energy of the laser output （70 and 120 W, respectively）. The vaporesection speed, coagulation zone depth and the necrotic tissue layer in the prostatic tissue were evaluated. The current result showed that the speeds （mean±s.d.） of vaporesection were 5.21±0.66 and 10.39±1.15 g/5 min for the 70 and 120 W groups, respectively （P=0.000）. There was no difference in the depth of necrosis/ coagulation （0.98±0.1310.30±0.09 and 0.99±0.12/0.31±0.08 mm） for the 70 and 120 W groups, respectively. In conclusion, both 70- and 120-W 2μm laser devices had superficial tissue damage during the vaporesection of human prostate tissue; moreover, the 120-W laser offers a higher vaporesection speed than the 70-W laser.

Observation and optimization of 2 μm mode‐locked pulses in all‐fiber net anomalous dispersion laser cavity

We integrally demonstrate 2μm mode-locked pulses performances in all-fiber net anomalous dispersion cavity.Stable mode-locking operations with the center wavelength around 1950–1980 nm can be achieved by using the nonlinear polarization rotation structure and properly designing the dispersion management component.Conventional soliton is firstly obtained with a total anomalous dispersion cavity.Due to the contribution of commercial ultra-high numerical aperture fibers,net dispersion is reduced to-0.077 ps2.So that stretched pulse with 19.4 nm optical bandwidth is obtained and the de-chirped pulse-width can reach 312 fs using extra-cavity compression.Under pump power greater than 890 mW,stretched pulse can evolve into noise-like pulse with 41.3 nm bandwidth.The envelope and peak of such broadband pulse can be compressed with up to 2.2 ps and 145 fs,respectively.The single pulse energy of largely chirped stretched and noise-like pulse can reach 1.785 nJ and 1.53 nJ,respectively.Furthermore,extra-cavity compression can also contribute to a significant increase of peak power.

Spectral and laser properties of Yb and Ho co-doped(YLa)_2O_3 transparent ceramic

Highly transparent Yb,Ho doped（YLa）2O3 ceramic was fabricated by conventional ceramic processing with nanopowders.The absorption and emission spectra of the ceramic was investigated.The energy transfer mechanism between Yb3＋ and Ho3＋ was also discussed.The strong emission band around 2 μm indicated that the Yb-Ho：（Y 0.90 La 0.10）2O3 transparent ceramic is a promising gain medium for the generation of 2 μm laser emissions.The laser operation of Yb-Ho co-doped（YLa）2O3 ceramic at 2.1 μm is first reported.

MXene Ti_3C_2T_x saturable absorber for pulsed laser at 1.3 μm

The excellent optical properties of MXene provide new opportunities for short-pulse lasers. A diode-pumped passively Q-switched laser at 1.3 μm wavelength with MXene Ti3C2Tx as saturable absorber was achieved for the first time. The stable passively Q-switched laser has 454 ns pulse width and 162 kHz repetition rate at 4.5 W incident pumped power. The experimental results show that the MXene Ti3C2Tx saturable absorber can be used as an optical modulator to generate short pulse lasers in a solid-state laser field.

MICROSTRUCTURE IN LASER FUSED HIGH SPEED STEEL W6Mo5Cr4V2(M2)

Microstructure of the deepest zone of high speed steel W6Mo5Cr4V2(M2)melt after laser fu-sion was found to be so fine as the ehill zone of a solidified ingot.When narrower chill zoneformed,the long columnar dendrites grow into the melt and then the fine equiaxed cellularstructure appears in upper melt region nearly surface.The substructure of cellular grains anddendrites was observed to consist of martensite and retained austenile,while the carbides asM_6C_■ Cr_7C_3 and MC distributed at their boundaries.It is believed that the highermicrohardness up to HV_(0.1)=865-960 of the laser fused structure of the alloy is due to the oc-currence of martensite.

Comparative study of pulsed laser diode end-pumped thulium-doped 2-µm Q-switched lasers

We report pulsed laser diode(LD)end-pumped acoustic Q-switched Tm:YAG laser,Tm:LuAG laser,and Tm:LuYAG laser and the physical properties and spectra of Tm:YAG,Tm:LuAG,and Tm:LuYAG are analyzed.The Tm:LuYAG laser is pumped by 785-nm and 788-nm pulses separately,and is compared with Tm:YAG laser.Different output energy values and output wavelengths of Tm:LuAYG lasers pumped by LDs with different wavelengths are obtained and compared with each other.When the repetition frequency is 100 Hz,the pulsed Tm:YAG laser has single pulse energy of 15.9 mJ,pulse width of 126.7 ns,and the center wavelength of 2013.36 nm,and the pulsed Tm:LuAG laser possesses single pulse energy of 11.8 mJ,pulse width of 252.4 ns,and the center wavelength of 2023.65 nm,and the pulsed Tm:LuYAG laser output energy values are 12.32 mJ and 12.25 mJ with the slope efficiencies of 12.5%and 11.85%,the center wavelengths of 2017.89 nm and 2027.11 nm,respectively,while the pump sources are 785-nm and 788-nm pulsed LDs,respectively.

In Vitro Study on the Vaporization Ratio of 2-μm Laser in Human Prostatic Tissue

In this study, the vaporization ratio of the 2-μm laser in the prostatic tissue with benign prostatic hyperplasia was examined in vitro, to explore a technique to estimate the clearance rate of prostatic tissue during the transurethral vaporesection of the prostate. A total of 9 fresh prostatic tissue specimens were obtained by open surgery and the wet weight of the prostatic tissue were measured immediately after the sample collection. Under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, each prostate gland was completely vaporesected into fragments with a diameter of less than 1.0 cm in vitro tissue were collected and measured. Then After the vaporesection, the whole fragments of prostatic the lost weight of prostatic tissue, the weight of the collected prostatic tissue and the ratio of the lost weight of prostatic tissue to the wet weight of the prostate glandular organ specimen were calculated. The correlation between the weight of collected prostatic tissue and the weight of the whole glandular organ was analyzed. All the experimental procedures were carried out by one operator. Wet weight of the prostatic gland specimen and the weight of the harvested prostatic tissues after the procedure were recorded. With respect to the wet weight of prostate gland specimen, the percentage of the weight of collected prostatic tissue was （34.45±1.51） %, and the percentage of the lost weight of prostatic tissue was （65.55±1.51）%. Satisfactory linear relationship was observed between the weight of collected prostatic tissue and the wet weight of prostate gland specimen [y=3.245x=6.475 （t=15.097, P=0.000）]. It is concluded that under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, the vaporization ratio of prostatic tissue can be calculated on the basis of the weight of collected prostatic tissue, and thereby the clearance of prostatic tissue during the formal operation by 2-μm laser could be quantitatively determined.

Combined Carbon Dioxide Laser Lateral Canthotomy and Femtosecond Laser-Assisted Cataract Surgery

Purpose: The purpose of this study was to evaluate a new procedure aimed at lengthening the palpebral fissure to facilitate femtosecond laser-assisted cataract surgery in patients with small eyes. Method: A quick procedure using the CO2 laser was adapted for patients with small eyes undergoing laser-assisted cataract surgery using the Catalys system. The UniPulse CO2 laser (Nidek) was used for laser lateral canthotomy on patients with small palpebral fissures to allow fitting of the Liquid OpticTM Interface eyepiece. Results: Lateral canthotomies were performed on 19 women and 7 men (ages ranged from 45 to 93 years) with lower eyelid lengths equal to or shorter than 32 mm who then underwent femtosecond laser-assisted cataract surgery. A total of 33 eyelids received laser lateral canthotomy with the CO2 laser;only one eyelid had lateral canthotomy with cold-steel tenotomy scissors. Dockings were completed for all 34 eyes with eyelids receiving lateral canthotomies. The 33 eyes with eyelids that received laser canthotomy with the CO2 laser had successful femtosecond laser-assisted cataract surgery. The one eye with the eyelid that received cold-steel canthotomy could not have femtosecond laser-assisted cataract surgery despite successful docking because of pupillary constriction. The findings were statistically significant;Fisher Exact Test showed a p-value of 0.0294. Conclusion: Laser lateral canthotomy with CO2 laser is a safe and effective method to allow docking and completion of femtosecond laser-assisted cataract surgery.

Transurethral prostate enucleation with 2 μm laser in treatment of benign prostatic hyperplasia

Objective To investigate the feasibility and efficacy of transurethral prostate enucleation with 2 μm laser in treatment of benign prostatic hyperplasia ( BPH) . Methods One hundred and seven patients with BPH were treated by transurethral prostate enucleation with 2 μm la-

15μm波长DFB半导体激光乙炔(^(12)C_2H_2)线性吸收稳频

建立 1 5 μm波长标准的工作既是现实应用的需求 ,也将填补波长计量标准系列在近红外波段的空白。本文报导中国计量科学研究院在这项研究中的第一阶段工作 :用国产分布反馈半导体激光 (DFB LD)和自行研制的乙炔 (1 2 C2 H2 )吸收室 ,进行了吸收光谱实验 ,实现了 1 5 μmBFB LD的C2 H2 线性吸收稳频。

膀胱黏膜下良性肿瘤经尿道2μm激光剜除术2例报告并文献复习

本文回顾分析2013年5月和2014年12月2例膀胱黏膜下良性肿瘤采用经尿道2μm激光肿瘤剜除术治疗的病例资料,并复习有关文献,总结诊治经验。均为女性,年龄47、57岁,均因间断尿频、尿急、尿痛来诊,CTU及膀胱镜检查均提示黏膜下非上皮性膀胱肿瘤,良性可能。手术过程顺利,均完整切除肿瘤,无并发症发生,术后3天均拔除尿管,无明显血尿。术后病理均为膀胱平滑肌瘤。术后分别随访24、6个月,未见肿瘤复发或转移。

截断平顶高斯光束M^2因子的比较研究

使用熵束宽、渐近分析和环围功率法对截断平顶高斯光束的束腰宽度w、远场发散角θ0和M2因子作了比较研究.结果表明:按不同束宽定义得到的截断平顶高斯光束的w、θ0和M2因子不同,且与截断参量a/ w0(a为光阑半宽度,w0为平顶高斯光束初始束腰宽度)有关.随a/ w0的增加,三种方法计算得到的w、θ0和M2都分别趋于某常量.

非傍轴截断双曲余弦高斯光束的M^2因子

基于功率密度的二阶矩方法,对非傍轴截断双曲余弦高斯(ChG)光束的束宽、远场发散角和M2 因子进行了研究。数值计算结果表明,非傍轴截断ChG光束的M2因子不仅与截断参数δ、偏心参数α有 关,而且与初始束腰宽度和波长之比ω0／λ有关。在δ足够小时,M2因子可小于1。当δ→0时,远场发 散角趋于渐近值63．435°。对于α=0(Ω0=0)和δ→∞的特例,我们的结果分别退化为非傍轴截断高斯 光束和非傍轴无截断ChG光束的M2因子。

部分相干厄米-高斯光束在湍流大气中的M^2因子

基于广义惠更斯-菲涅耳原理和Winger分布函数二阶矩的定义,推导出部分相干厄米-高斯(PCHG)光束在湍流中的M2因子的解析表达式,并进行了数值计算和分析.研究结果表明:湍流中PCHG光束的M2因子由光束的阶数、相干长度、束腰宽度、波长以及湍流的折射率起伏结构常数和传输距离来决定;随着光束阶数、大气湍流的折射率起伏结构常数以及传输距离的增大,以及光束相干长度的减小,PCHG光束在湍流大气中的M2因子明显增大;对于给定的传输距离,存在最佳初始束宽使大气湍流中PCHG光束的M2因子最小;完全相干厄米-高斯光束和高斯-谢尔模型(GSM)光束在大气湍流中的M2因子变化规律可以作为本文研究的特例.

2μm激光在肾癌保留肾单位手术中的临床应用(附5例报告)

目的探讨2μm激光在肾癌保留肾单位手术中的临床应用效果。方法经腰开放手术下使用功率50W的2μm激光对5例无症状肾癌患者行保留肾单位的肾肿瘤切除术,患者均为男性,平均年龄47岁,均为单侧,左侧4例,右侧1例。结果5例患者均手术成功,手术时间105～120min,平均110min,术中出血80～400ml,均未输血,未出现术中集合系统损伤、术后尿瘘、术后出血及急性肾功能不全等并发症,肾周引流管留置时间4～5d。术后病理示5例患者均为肾脏透明细胞癌。结论2μm激光用于肾癌保留肾单位手术止血效果佳,出血少,切除完整,是对肾癌保留肾单位手术方式的新的探索。

部分相干平顶光束在增益或损耗介质中传输的M^2因子

根据光束在介质中传输强度二阶矩计算公式,推导出部分相干平顶光束在增益或损耗介质中传输的M2因子解析表达式,并将高斯-谢尔模型光束在增益或损耗介质中的传输作为特例统一于一般表达式中。研究结果表明:部分相干平顶光束在增益或损耗介质中传输时的M2因子与光束传输距离、光束相干长度、光束阶数及介质的特性有关。光束在增益或损耗介质中传输的这种特性为应用和控制光束传输提供了理论依据。

激光引信发射组件M^2因子的测试研究

激光引信发射组件中,由于线性阵列激光二极管的光斑是由若干激光二极管的光斑叠加而成,其M2因子的测量不能简单地按照单个激光二极管M2因子的方法进行测量。以ISO11146标准中的二阶矩法为基础,使用CCD采集聚焦后的光斑图像,并对光斑图像进行分块处理,从而得到激光引信发射组件的M2因子。

Thulium laser treatment for bladder cancer

Recent innovations in thulium laser techniques have allowed application in the treatment of bladder cancer.Laser en bloc resection of bladder cancer is a transurethral procedure that may offer an alternative to the conventional transurethral resection procedure.We conducted a review of basic thulium laser physics and laser en bloc resection procedures and summarized the current clinical literature with a focus on complications and outcomes.Literature evidence suggests that thulium laser techniques including smooth incision,tissue vaporization,and en bloc resection represent feasible,safe,and effective procedures in the treatment of bladder cancer.Moreover,these techniques allow improved specimen orientation and accurate determination of invasion depth,facilitating correct diagnosis,restaging,and reevaluation of the need for a second resection.Nonetheless,large-scale multicentre studies with longer follow-up are warranted for a robust assessment.The present review is meant as a quick reference for urologists.