Laser irradiation parameters, especially the laser fluence and the number of pulses are very important factors affecting microstructures formation and improvement of the surface characteristics in different medical, electronic and the other industrial applications. Information about the fluence domain and the number of pulses for the formation of the structures is very important and determines the desirable or unwanted effects of the laser irradiation on the surfaces regarding the desired applications. In this paper Polyethersulfone films were irradiated with a XeCl laser at fluences above the ablation threshold. The effects of the laser fluence and the number of pulses on the formation of different microstructures on the surface were investigated.

Purpose: To evaluate the histopathologic features of optic neurotomy with microvitreoretinal (MVR) blade and excimer laser in cadavereyes.Method: Optic neurotomy was performed in 11 cadaver eyes using 20-gauge MVR blade and in three cadaver eyes with pulsed xenon chloride (XeCl) excimer laser (308nm) via monofile light conducting fiber with a core diameter of 200 microns. After tissue processing, hematoxylin and eosin stained slides were used to evaluate the posterior segment of the globes, including the optic nerve head.Results: None of the cases in the MVR neurotomy group had sclera macro- or micro-perforation and no injury was induced to the central retinal vein or artery. In 10 cases, the distance between the neurotomy site and the central retinal vessels ranged from 50 to 500m at all histologic levels. In one remaining case this distance was approximately 10m on two histologic sections and about 200m at a third level. Intra-neural hemorrhage was found in 18% of cases. Neurotomy was successfully induced in two of three cases attempted with the excimer laser. In one case, due to cloudy media, it was not apparent whether the laser successfully induced the neurotomy and no neurotomy was evident on sectioning.Conclusion: MVR induced optic neurotomyis an effective procedure to create scleral outlet relaxation, without significant surgical complications such as scleral perforation or central retinal vascular injury. This preliminary study also demonstrates that the XeCl excimer laser can make non-mechanical cuts with relative ease and reliability.

Background and Aim: Undesirable appearance of the scar tissue after aesthetic surgery can affect the outcomes and patient satisfaction. In recent years, early laser therapy had been encouraged to reduce the scar tissue formation. However, the available evidence regarding the outcomes of laser therapy utilizing combined lasers are limited. In the current study, the effects of combined laser therapy using pulsed dye laser (PDL ) and fractional CO2 laser on the appearance of the scar tissue after aesthetic surgeries were investigated. Methods: There were 15 patients enrolled in the current study including 13 mammoplasty and 2 abdominoplasty patients. In mammoplasty, each breast was randomly assigned to the laser therapy or control group. In abdominoplasty, split scar design was used. In laser therapy group, at the end of the third postoperative week, PDL 585 nm was radiated. Furthermore, at the end of the sixth week, fractional CO2 laser was radiated. The patients were followed for 6 months after the last laser therapy session. Visual analogue scale was used to rate the appearance of the scar tissues by 3 surgeons blinded to the treatment of scars. The appearance of the scars was determined as poor, fair, good or excellent. Results: VAS averaged 5. 5±, 0. 8 in laser therapy group and 4. 8±, 0. 8 in the control group. The difference was not statistically significant (P=0. 057 ). There was no scar with excellent appearance in the current study. All of the scars were fair and good in the laser therapy group. In the control group, 13 scars were fair. The difference was not significant (P=0. 227 ). Conclusion: Early combined laser therapy using PDL and fractional CO2 laser was associated with improved appearance of the scar tissue in short-term follow up, however, the effects were not statistically significant.

Pulse Dye Laser (PDL) is mainly used to treat vascular lesions but several studies performed in different research centers have shown the efficacy of this safe laser in the treatment of non-vascular lesions as well. The aim of this study was to review, sum up and summarize these studies.PDL is a known alternative for cryotherapy in the treatment of some viral lesions such as periungual warts and molluscum contagiosum. The effect of this laser in the management of inflammatory lesions is not yet known and there have been controversial results. PDL has a very little effect on these dematoses and it is limited to the lesions with a clear vascular component, such as psoriasis and acne. Finally, regarding collagen remodeling and its usage in rejuvenation and in the treatment of hypertrophic scars, keloid and striae, the results from various studies are different and while they confirm its possible effect, more studies have to be conducted in order to determine appropriate treatment parameters.

Background: Tracheal intubation is a very common procedure for maintaining patency of airway in critically ill patients. Intubation may lead to local complications such as tracheal destruction and post-intubation stenosis. There are two different therapeutic approaches for such patients. The first one is surgical end-to-end anastomosis suitable for severe destructions and fibrosis formations. The second and novel method is utilization of Nd-YAG laser that can correct intraluminal airway lesions including webs, granulation tissues and fibrous bands. Nd-YAG laser employment decreases hospitalization period, complications and, expenses; in addition, it saves medical staffs time and energy.Materials and Methods: An uncontrolled clinical trial was performed in post-intubation tracheal stenosis cases admitted to "National Research Institute of Tuberculosis and Lung Disease" (NRITLD) between 1994 to 1999. Bronchoscopy was performed for all patients, and those with the following inclusion criteria underwent Laser therapy: length of stenosis less than 2 cm, tracheal lumen diameter more than 5mm, and granulation tissue type lesions. Patients who did not meet the aforementioned criteria were referred for surgical interventions. Leaser therapy was employed by fiberoptic bronchoscopy under local anesthesia. For those patients with tracheal lumen diameter between 5-10 mm rigid bronchosopy was performed under general anesthesia.Results: Of 32 patients, 25 met the primary criteria for Laser therapy, from which 22 (88%) were completely cured. Because of poor general condition, 5 of 7 other patients who had been referred for surgery, underwent Laser therapy, therefore a total of 30 patients (93%) took advantage of this technique. Overall, 23 patients were treated only with Laser therapy, 2 patients only with surgery and 7 patients with a combination of these two approaches.Conclusion: This trial revealed that if patients with post-intubation tracheal stenosis are selected correctly, Leser therapy can be used as a beneficial and safe method with satisfactory results.