Nd:YAG激光虹膜周边切除术治疗闭角型青光眼的临床研究

目的探讨Nd：YAG激光虹膜周边切除术治疗闭角型青光眼的疗效。 方法26例30只眼闭角型青光眼分为AB两组，A组为中周部高能量组（首次击射能量为7．4mJ），B组为极周边部低能量组（首次击射能量为5．3mJ），行Nd：YAG激光虹膜周边切除术。 结果两组患者均穿孔成功，A组并发症较B组明显减少，且一次穿孔率达100％。 结论Nd：YAG激光虹膜周边切除术治疗闭角型青光眼疗效可靠，并发症少，值得推广应用。     

钬激光腔内治疗泌尿系结石(附126例报告)

目的：探讨泌尿系结石腔内钬激光治疗效果及安全性。方法：总结钬激光结合腔内泌尿外科技术治疗126例泌尿系结石的临床资料。结果：5例肾结石和11例膀胱结石，均一次碎石成功，109例输尿管结石，单次碎石率为96.3%(105/109)，复杂结石1例数次行输尿管腔镜下碎石。平均结石排净时间2.8周，平均手术时间30min，平均术后住院2d。术中除1例输尿管穿孔外，无其他并发症。结论：钬激光结合腔内泌尿外科技术治疗泌尿系结石，是一种较新的、安全的、有效的方法。     

Thermal analysis of the bone surface induced by laser radiation

High energy laser has emerged to be an important surgical tool in medical technology. However, the application of laser energy to drill or cut a bone is still in an experimental state. In order to estimate the adequacy of laser heating of bone surface and at the same time minimize the damage to the bone tissue, we developed a mathematical model of the temperature distribution in bone due to laser irradiation. The thermal analysis shows that the temperature distribution depends on several parameters, including the density, the specific heat, and the thermal conductivity of the osseous tissue.     

Fluorescence behaviour of human arterial tissue

Total fluorescence from arterial tissue is influenced by three factors: the absorption coefficient of tissue at a specific excitation wavelength, the laser excitation power and the fluorescence coefficient which is related to chemical species in tissue. These various influences were demonstrated by the following experimental results in vitro: (1) the effect of increasing power on fluorescence intensity, (2) the total fluorescence intensity in normal aorta and plaque and (3) the effect of a chromophore such as β-carotene on total fluorescence intensity. The fluorescence intensity of normal artery is an incremental function of laser excitation power, and the fluorescence emission from normal artery compared to fluorescence emission from plaque is significantly different at the same excitation power. The total fluorescence of normal artery was measured to be twice as great as that of atheromatous plaque (relative mean ratio of 2.58±0.46 compared to unity,p<0.0002 at 488 nm; relative mean ratio of 2.57±0.51 compared to unity,p<0.0009 at 514 nm). The total fluorescence emission decreases with the increase of β-carotene content in arterial tissue (R=0.97). These emission differences, when intensified by an exogenous chromophore of β-carotene, may provide an improved guidance signal for diagnosis of plaque from normal artery during laser angioplasty procedures.     

A role for lasers in the treatment of pigmented skin grafts

The development of aberrant pigmentation represents an unwelcome complication to an otherwise successful split skin graft resulting in a loss of colour match and, so it follows, of cosmesis. We present two cases where lasers have been successful in the treatment of this problem.     

Does the shunt opening pressure influence the effect of shunt surgery in normal pressure hydrocephalus?

Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure.     

Na~（3＋）─YAG激光治疗耳鼻咽喉常见疾病286例

笔者用Ｎａ３＋－ＹＡＧ激光治疗耳鼻咽喉常见疾病２８６例，疗效满意。激光手术较常规手术操作简便，术中出血少，反应轻，并发症少，病人痛苦少，值得推广。     

The bactericidal activity of pulsed Nd-YAG laser radiation in vitro

Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples. Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species 120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro.     

川芎对脑血管血液动力学参数作用的实验研究

我们用食饵性高血脂加异种血清反复静脉注射造成动脉内皮免疫性损伤的方法,建立了兔实验性动脉粥样硬化模型,观察了中药川芎对脑血管血液动力学参数(CVHP)的影响。发现川芎组CVHP各项指标均与正常对照组接近,与正常组比较,无显著性差异,颈动脉平均血流量(Qmean)、平均血流速度(Vmean)、最小血流速度(Vmin)、脑血管零压顺应性(CO)和脑血管外周阻力(R)等指标显著优于动脉粥样硬化组(P<0.05～0.01)。本实验结果提示川芎对脑血管功能具有保护作用。