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Patients with chorioretinal colobomas are at a risk of rhegmatogenous retinal detachment as a consequence of retinal breaks that occur in the abnormally thin colobomatous or extra colobomatous reti...

Purpose To investigate the efficacy of fortified barrier laser (FBL) on the vitreous base in vitrectomy for rhegmatogenous retinal detachment (RRD). Patients and methods This was a retrospective study of patients who underwent vitrectomy for RRD without proliferative vitreoretinopathy. Barrier laser was applied as 3-4 rows surrounding the break at the end of fluid-air exchange. For the FBL, 3-4 rows of laser burn were additionally made about 0.5 clock-hour long adjacent to the break along the posterior border of the vitreous base. The primary outcome was single surgery success rate (SSSR) between two groups: FBL and conventional barrier laser (CBL) groups. Results Overall, 118 eyes were included; 50 eyes in the FBL group and 68 eyes in the CBL group. SSSR was 100% (50/50) in the FBL group and 91.2% (62/68) in the CBL group with a significant difference (p=0.038). Four eyes of the recurrent cases in the CBL group were related to reopening of the break. All eyes achieved reattachment, and no differences were found in postoperative visual acuity at 6 months. Conclusion FBL on the vitreous base was efficacious in improving the anatomical success rate of vitrectomy.

Despite the achievements in modern medicine, there is no effective natural treatment of second-degree burns till now. Therefore, the purpose of this study was to assess the wound-healing efficiency of three extracted oils, from the prickly pear, pumpkin and linseed on partial-thickness burns induced by fractional CO2 laser (an innovative up-to-date technique) in rats.Thirty rats completing partial-thickness burns by fractional CO2 laser were randomly divided into five groups. The burns were measured, photographed, and topically treated daily with saline solution, "CYTOL BASIC," pumpkin-, linseed-, and prickly pear-extracted oils (0.52 μL/mm(2) of oil) until day 7. The response to treatments was assessed by macroscopic, histologic, and biochemical parameters.Due to their chemical composition, the extracted oils showed significant improvements over the control and reference groups during the trial for both general wound appearance and crusting. On day 7, the prickly pear, linseed, and pumpkin oils showed a significant decrease in the healing time (0 cm(2), 0.15 cm(2), and 0.18 cm(2), respectively) when compared to the control and reference groups (1.49 cm(2) and 0.85 cm(2)). Histologic assessment of the prickly pear oil-treated group revealed good healing proprieties compared with the other groups. The collagen content in prickly pear oil-treated group was found to be significantly greater (270.67 ± 7.48) than that in all other groups.Our experiment has shown, for the first time, a scientific evidence of the efficiency of extracted oils of prickly pear, pumpkin, and linseed on partial-thickness burns.

PURPOSE To present a case of a patient who suffered a macular burn after an attempted YAG laser capsulotomy because of the inadvertent use of the selective laser trabeculoplasty mode of a dual-mode laser. METHOD Case report. RESULTS A 62-year-old man with slight opacification of the posterior capsule noted sudden central vision loss immediately after an attempted YAG laser capsulotomy. The selective laser trabeculoplasty mode of a dual-mode laser had inadvertently been used. Color photographs, fluorescein angiography, and spectral domain optical coherence tomography revealed a laser burn in the macula. The patient's central vision was impaired. CONCLUSION Inadvertent selection of the selective laser trabeculoplasty mode when attempting to perform a YAG laser capsulotomy with a dual-mode laser may cause a macular burn with impairment of central vision. We encourage all users of dual-mode lasers to actively choose and verify the appropriate settings to minimize the risk of inadvertent retinal damage.

Purpose. To compare the controllability of navigated macular laser photocoagulation (MLP) in dry versus edematous retina and validate that pretreatment diagnostic images can be used as basis for navigated MLP after the macular edema (ME) has been resolved.Materials and Methods. Group 1 was divided into subgroup 1 (dry retina MLP) and subgroup 2 (MLP in ME) for comparisons of laser-burn diameters. In group 2, the areas and locations of ME before an intravitreal injection of anti-VEGF (IVAV) were compared with those of recurrent ME.Results. The average actual diameter as percentage of planned diameter of laser burn in subgroup 1 (11 DME eyes, 6 BRVO eyes) versus subgroup 2 (5 DME eyes, 8 BRVO eyes) was 115.1 ± 9.1% versus 167.2 ± 13.8% (based on retro-mode scanning laser ophthalmoscopy), and 118.1 ± 14.8% versus 176.1 ± 11.6% (based on OCT) (p<0.001). In group 2 (6 DME eyes, 6 BRVO eyes), difference in mean ME area before IVAV and that in recurrent edema was insignificant (p>0.05).Conclusion. The controllability of navigated MLP in dry retina is improved compared to edematous retina. This study validates that pretreatment diagnostic images can be used as basis for navigated MLP after the edema has been resolved.

Context: Since antiquity, Pistacia lentiscus L. (Anacardiaceae) fruit oil (PLFO) has been used as a remedy for primary health care such as burn treatment. Objective: This study assesses the healing effect of PLFO on CO2 laser fractional burn in a rat model. Materials and methods: The study was carried out on 18 adult male Wistar rats. A second-degree laser burn (wound area = 2.2 cm2) was inflicted in the dorsal region by the application of CO2 fractional laser within the following parameters; Energy level: 25 MJ and Depth level: 4. After applying laser, the rats were divided into three groups: the first was treated with saline solution, the second with a reference cream ‘CYTOL BASIC®’ (0.13 μg/mm2) and the third with PLFO (0.52 μL/mm2). All treatments were topically administered for eight days. The healing effect was assessed using macroscopic, histological and biochemical parameters. Results: After eight days, the higher percentage of wound healing contraction was observed among the PLFO-treated group (100%) followed by the ‘CYTOL BASIC®’ treated group (61.36%) and untreated group (32.27%). During the treatment, the PLFO-treated group showed less erythema, less crusting/scabbing, higher general wound appearance scores and a high content of collagen (220.67 ± 7.48 mg/g of tissue) than the other groups. Discussion and conclusion: The current study has shown, for the first time, the healing effect of PLFO on CO2 laser fractional burn. Their wound healing effect could be attributed to their antimicrobial, anti-inflammatory and antioxidant effects.

Background and Objective: In laser retinal photocoagulation, hundreds of dot-like burns are applied. We introduce a robot-assisted technique to enhance the accuracy and reduce the tedium of the procedure. Materials and Methods: Laser burn locations are overlaid on preoperative retinal images using common patterns such as grids. A stereo camera/monitor setup registers and displays the planned burn locations overlaid on realtime video. Using an active handheld micromanipulator, a7 � 7 grid of burns spaced 650mm apart is applied to both paper slides and porcine retina in vitro using 30 millisecomds laser pulses at 532 nm. Two scenarios were tested: unaided, in which the micromanipulator is inert and the laser fires at a fixed frequency, and aided, in which the micromanipulator actively targets burn locations and the laser fires automatically upon target acquisition. Error is defined as the distance from the center of the observed burn mark to the preoperatively selected target location. Results: An experienced retinal surgeon performed trials with and without robotic assistance, on both paper slides and porcine retina in vitro. In the paper slide experiments at an unaided laser repeat rate of 0.5 Hz, error was 125� 62mm with robotic assistance and 149� 76mm without (P < 0.005), and trial duration was 70� 8 seconds with robotic assistance and 97� 7 seconds without (P < 0.005). At a repeat rate of 1.0 Hz, error was 129� 69mm with robotic assistance and 166� 91mm without (P < 0.005), and trial duration was 26� 4 seconds with robotic assistance and 47� 1 seconds without (P < 0.005). At a repeat rate of 2.0 Hz on porcine retinal tissue, error was 123� 69mm with robotic assistance and 203� 104mm without (P < 0.005). Conclusion: Robotic assistance can increase the accuracy of laser photocoagulation while reducing the duration of the operation. Lasers Surg. Med. 42:264–273, 2010. 2010 Wiley-Liss, Inc.

Purpose: To establish a method allowing multifocal electroretinography (mfERG) recording with simultaneous fundus monitoring on anaesthetized pigs. In addition we characterize the peaks of the porcine mfERG trace, and compare the visual streak area with the optic nerve head, a known nonresponse area. Finally we illustrate the feasibility of the method by performing mfERG after an induced laser burn in the visual streak. Methods: Fifteen pigs underwent mfERG recordings at baseline, and after 1 and 6 weeks of observation. One pig was evaluated before and after retinal diode laser treatment in the visual streak. Results: The porcine mfERG trace appears similar to the human mfERG trace, and can be described by three peaks named N1, P1 and N2. Significantly faster implicit time was found in the visual streak regarding N1 ( P< 0.001) than in areas outside the visual streak. Amplitudes of all three peaks were increased in the visual streak ( P< 0.005). The laser-treated area was characterized by a response similar to what is found at the location of the optic nerve head. Conclusion: Porcine mfERG is similar in appearance to the human response and can be described by the same three peaks. Significantly higher amplitudes of all three peaks are found in the visual streak when compared to the optic nerve head and inferior retina. We have detected the functional deficit caused by a laser burn at the size of 3 · 3 mm.

The aim of presenting this article is to highlight the factors causing failure in endoscopic dacryocystorhinostomy (DCR). Understanding these factors will lead to an enhancement in the success rate of endoscopic DCR. Out of 600 cases done in a period of 10 years (from 1998 to 2008), 60 were revision cases. 60 patients referred over a period of 10 years, were selected. The aim was to study the factors causing failure in each case. The cases included were revised in a period of 10 years from 1998 to 2008. These were the cases that were unsuccessful for one or the other reason. The author presents a series of failed DCR cases referred over a period of 10 years. Patients had undergone primary surgery elsewhere and were referred due to the persistence of symptoms. Assessment of all the cases was done with the examination of Eyes and lids for any obvious deformity, watering or purulent discharge in the medial canthal area. ROPLAS test was done as a spot diagnosis for NLD block. This was followed by probing and syringing in the outdoor. All the cases were revised and the likely causes leading to failure of the first surgery were analyzed. It was found that the improper selection of cases accounted for 3.3% of total failed cases; Low rhinostomy accounted for 28.3% cases, inadequate sac opening for 38.3% cases, Pre existing canaliculitis for 1.6% of cases, contracture at the rhinostomy site in 10% cases. Laser burn canalicular scarring for 3.3% of total cases and laxity of the lids and atonic sac was responsible for failure in 3.3% cases. Most of the above factors are secondary to the false localization of the sac, inadequate removal of the sac wall, too much of mucosal removal leading to synaechia formation at the surgical site and inability to detect any additional block with NLD (Nasolacrimal duct) block.

The purpose of the study was to determine histologic findings after successful laser trabeculoplasty in eyes with glaucoma. Previous studies have examined eyes in which laser did not lower intraocular pressure, or examined only the region of the laser burn itself. Nineteen autopsy eyes from 14 donors with either primary open angle or pseudoexfoliative glaucoma that had undergone laser trabeculoplasty during life were studied. Clinical records were used to determine the effect of laser in lowering intraocular pressure (IOP). For comparison, 49 glaucomatous eyes that had not undergone laser, and 55 normal eyes were studied as control eyes. Histologic sections from multiple quadrants of each eye were studied by light microscopy, selecting regions between laser spots when the spots were visible. Meshworks from lasered eyes frequently had regions of an expanded juxtacanalicular region associated with numerous superimposed giant vacuoles partially filling Schlemm's canal. This finding was more common in eyes fixed by posterior chamber perfusion, occurring in 90% (9/10) of lasered eyes, while it was found in only 20% (3/15) of glaucomatous control eyes (p = 0.01) and 33% (14/43) of normal eyes (p = 0.01). The mean decrease in IOP caused by laser was 34% ± 14%, with mean follow-up time before death of 2.7 ± 1.7 years. In eyes fixed by immersion the expanded JCT finding was less common, occurring in 22% (2/9) of lasered eyes, but only 9% (3/34) of glaucomatous control eyes and 8% (1/12) of normal eyes. The mean decrease in IOP in these eyes was 39% ± 10%, with mean follow up of 2.3 ± 1.0 years until death. Downgrowth of Descemet's membrane over the meshwork was observed in portions of two of the 19 lasered eyes. In conclusion, laser trabeculoplasty associated with decreased IOP appears to cause a remodeling of the juxtacanalicular region of the meshwork. This may be a dynamic, flow dependent finding, as it was more common in eyes fixed by perfusion. Downgrowth of Descemet's membrane over the meshwork was uncommon.

Sohee Jeon, Won Ki Lee Department of Ophthalmology, Seoul St Mary’s Hospital, College ofMedicine, The Catholic Universityof Korea, Seoul, Korea Abstract: Here we report two cases of retinal damage after exposure to a 510 nm laser diode during a laser show. The first patient was a 20-year-old female who presented with decreased visual acuity in her right eye after visiting a dance party with a diode laser show (wavelength 510 nm, power 2 mW), although she did not directly see the light. Retinal examination revealed a sub-internal limiting membrane hemorrhage and a small laser burn. The second patient was a 20-year-old female who visited for decreased vision in her left eye. She described similar events as the first patient. An exposure to green diode laser can result in retinal damage. It is strongly recommended that certified personnel operate laser devices used in indoor laser shows under strict regulation. Keywords: green diode laser, sub-internal limiting membrane hemorrhage, inner retinal damage

Objectives To perform an analysis of currently available manufacturer data regarding the character of ureteroscope damage. The high costs associated with the repair of flexible and semirigid ureteroscopes are well documented. Increased knowledge of the etiology of ureteroscope damage should aid urologists in prolonging the lives of these delicate instruments. Methods We requested data from the four major ureteroscope manufacturers (ACMI, Olympus America, Karl Storz, and Richard Wolf) on the types, speculated causes, costs, and frequency of ureteroscope damage. The results were tabulated in a blinded fashion and analyzed for trends. We then formulated guidelines that could be applied by practicing urologists. Results For both flexible and semirigid ureteroscopes, the frequency of repair increased with decreasing ureteroscope diameter and increasing instrument length. The cost of the repair was generally greater for flexible ureteroscopes (mean $4597) than for semirigid ureteroscopes (mean $2437). The major causes of flexible ureteroscope damage were working channel damage from laser burn or instrument passage and extreme scope deflection with an indwelling instrument. The primary reasons for semirigid ureteroscope repair included overtorquing and improper handling in the operating room and during sterile processing. Conclusions Urologists can minimize the repair costs of flexible and semirigid ureteroscopes by taking precautions to eliminate laser fiber-induced damage and by avoiding overdeflection. Improved storage and handling of these instruments is also necessary. Although small-diameter ureteroscopes are favorable because of their increased mobility and ease of passage, physician and staff awareness of their increased fragility is vital in maximizing the longevity of these commonly used instruments.

Background and Objectives Experimental animal study of burns is dependent on a reliable burn generation system. Most of the experimental systems used today are unable to produce precise partial thickness burns. This limits the ability to study minor changes associated with burn care. The aim of the study was to develop a method for generating burns with a fixed depth using a CO2 laser burn generation system. Materials and Methods The burn generation system was composed of two components: a burn generation device and a temperature sensing and control system. These components were designed to operate together in order to keep a constant, predetermined skin surface temperature during prolonged burn generation. One hundred thirty-eight spot burns were generated on the back of five shaved 450 g male Wistar rats. The rat skin was exposed to a 70°C for 5–60 seconds. The burned areas were excised and underwent evaluation by hematoxylin-eosin-stained slide microscopy. Results A linear correlation was found between the duration of exposure and the average burn depth (r = 0.93). This correlation is represented by the equation: burn depth in millimeters = 0.012× (duration in seconds of skin exposure at 70°C). Conclusions The fiber-optic-controlled laser burn generation system studied is a reliable tool for creating partial thickness as well as full thickness skin burns in rats. Lasers Surg. Med. 32:413–416, 2003. © 2003 Wiley-Liss, Inc.

We describe our use of an indirect ophthalmoscope argon laser for the treatment of selected retinoblastomas. The essential aspect of the technique is the creation, using the "continuous" exposure setting, of a confluent white laser burn completely around the tumor base. This procedure results in the prompt regression of most tumors, although several sessions, 1 to 4 weeks apart, are usually necessary for all but the smallest lesions. This method of laser treatment is applicable to retinoblastoma tumors located anywhere in the ocular fund us, including ones adjacent to the ora serrata.

Ziahosseini and colleagues report a maculopathy after a self administered laser burn from a laser pointer.1 Unfortunately, such injuries are likely to become more common because of the widespread availability of these …

Macular laser treatment with a thermal laser can result in permanent scotoma at the laser burn site.1 We report on a teenager who presented with central scotomas from a high powered handheld laser pointer. He had bought a green diode laser pointer over the internet and shone the laser beam into his eyes while playing with it. Visual …

Interstitial laser photocoagulation (ILP) is a recently developed, minimally invasive technique of local tumour destruction within solid organs. It current limitation is the lack of an optimal imaging technique to demonstrate treatment effects. This study was designed to assess the role of breast MR (magnetic resonance) imaging in the guidance of ILP for the minimally invasive treatment of primary breast cancer. Thirty patients with symptomatic breast cancer diagnosed by cytology underwent ILP using a single fibre (n = 20) and four fibres (n = 10) prior to surgical excision. MR imaging was performed using a contrast enhanced T1W 3D FLASH sequence before and after laser treatment. Real time MR imaging of laser treatment was performed in 7 patients. Following resection the extent of disease, size of laser burn and the extent of residual tumour were correlated with the MR images. Per-procedural and delayed MR images accurately showed the extent of laser induced necrosis and residual viable tumour. The correlation coefficent (MR v Histopathological analysis) for the laser burn diameter and residual tumour was 0.90 and 0.89 respectively. In conclusion, post-contrast MR images can accurately define the extent of both laser induced necrosis and residual viable tumour following ILP treatment of breast cancer.

Laser energy delivered through optical fibers can produce potent controlled thermal dissolution of human coronary obstructive disease, thus widening the stenotic vascular lumen. The ease of vaporization and penetration depends not only on the physical properties of the laser beam but also on the physical characteristics of the atherosclerotic plaque. Lipid-laden plaques are more easily vaporized compared with plaques that are heavily calcified. In atherosclerotic animal models studied in vivo, laser radiation produced a charred lining around the evacuated area and rapid regeneration of a new endothelial lining. After several weeks, the laser-induced crater was still evident, and thrombogenesis was not a significant complication. Focal aneurysmal dilatation may develop when there is thermal injury of the medial layer, and acute perforation can occur if severe laser burn is extended beyond the adventitial layer. Further technical advances and achievements are needed before laser recanalization becomes a clinical reality.

The laser era was initiated by the theoretical development of the maser principle by Schawlow and Townes 1 in 1958, and its actual demonstration by Maiman 2 in 1960. Then there was extensive effort throughout the world, particularly in this country, to define the laser's physical, biological, and military potentials. Studies by Flock and Zweng, 3 also Campbell and his associates, 4 among others, have indicated potential usefulness of the laser in ophthalmology, but Zaret 5 and Jacobson 6 have added words of caution. This report concerns the first laser burn of the macula which has been carefully documented. It validates Zaret's warning that the initial burn may not be visible, yet leave a permanent loss of vision and a lesion that is readily seen at a later date. In February 1964, a student at a nearby college accidentally viewed a laser beam with his right eye. I examined him

The two major problems in laser burn surgery are the excision or removal of thermally injured tissue and the closure of the wound with a skin graft. The excision of a thermal burn performed with conventional instruments requires major blood volume replacement. Skin grafts placed on an excised surface must acquire new circulation in order to remain viable and survive. The ideal laser must cut or excise tissue efficiently, coagulate or close the ends of blood vessels, and permit the growth of new blood vessels into a skin graft.