bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photodynamic therapy for treatment of malignant cutaneous lesions
Authors: Waldow Stephen M. , Lobraico Rocco V. , Kohler Irmgard K. , Wallk Silas , Fritts Helen T. 
Published: March 2007

AbstractPhotodynamic therapy, employing either hematoporphyrin derivative or dihematoporphyrin ether as the photosensitizer and an argon‐pumped tunable dye laser as the activating light source, was used to treat ten patients who had primary or recurrent basal or squamous cell carcinoma or infiltrating ductal cell carcinoma lesions metastatic to the skin. Of the 155 sites that were treated, various degrees of edema, erythema, and necrosis, sometimes accompanied by blistering, were evident in all areas within 24 to 48 hours of light treatment. While our follow‐up periods are short, four patients are free of disease at eight months or more posttreatment, two patients have had recurrent and/or persistent disease within four months, and four patients died within nine months from metastatic disease or unrelated disorders. Continued investigation into the use of photodynamic therapy for treatment of malignant lesions appears warranted, based on these preliminary clinical results.
Injuries as an adverse reaction to clinically used laser devices
Authors: Rodriguez Juan G. , Sattin Richard W. 
Published: March 2007

AbstractSince the first use of lasers in ophthalmology in the early 1960s, applications for the medical laser have been found in many medical specialties. Despite their increasing usefulness, lasers have been reported to induce injuries. Few studies have tried to quantify the number of injuries caused by the clinical use of lasers. To address this issue, we surveyed physicians at the 5th Annual Meeting of the American Society for Laser Medicine and Surgery, May 1985. Forty‐two of the 226 physicians attending the meeting responded to the questionnaire about their experience with lasers in their practice. An average of 25 laser procedures per month were performed by the responding physicians, and 61.9% of them reported at least one complication. Of the complications reported in the survey, 33 occurred within the last 12 months for an overall rate of 2.7 incidents per 1,000 procedures performed. The most common complications reported were burns and scarring; however, bowel perforation and pneumothorax were among the more serious. The mean number of reported complications varied by the length and type of training in the use of the laser, with the lowest number of complications reported by respondents who had taken a training course lasting longer than 7 days within the last year. Our findings show that both minor and life‐threatening injury can be caused by the clinical use of medical lasers. Evaluation of the adverse effects of any medical technology, such as lasers, is needed to help guide recommendations for its safe use.
Thermal effects of lasers on dental tissues
Authors: Launay Y. , Mordon S. , Cornil A. , Brunetaud J. M. , Moschetto Y. 
Published: March 2007

AbstractThe thermal effects of Nd:YAG, argon, and CO2 laser beams are observed on enamel, dentin, and dental pulp by means of computerized infrared thermography and thermocouple. This study shows that the Nd:YAG laser beam deeply diffuses through the enamel and dentin to the pulp. The argon laser effects are inconsistent depending on whether the enamel surface is cleaned, but after cleaning, the superficial and deep temperatures are low. With the CO2 laser, the enamel and dentin surfaces reach very high temperatures, but only low temperatures are measured in the pulp chamber.
Endoscopic laser therapy for the treatment of malignant esophageal obstruction
Authors: Pietrafitta Joseph J. , Carstens Michael H. , Dwyer Richard M. 
Published: March 2007

AbstractMalignant esophageal obstruction in 24 patients was treated using the neodymium:ytrium, aluminum, garnet laser. There were 15 males and nine females; the average age was 70.9 years. There were 17 adenocarcinomas and seven squamous cell carcinomas, with two of these being recurrent after radiation therapy. Tumor lengths ranged from 2.5–19.0 cm, with an average of 6.7 cm. The average energy delivered per centimeter of tumor was 6,309 joules for the squamous cell carcinomas and 5,598 for the adenocarcinomas. Energy delivered per treatment ranged from 3,152 to 70,527 joules. Total energy delivered per patient depended on the volume of tumor destroyed. Esophageal lumens increased from 3.4 to 16.7 mm, and 23 patients had their diets advanced, 22 to regular and one to soft solids. Reobstruction did not occur in patients who received adjunctive therapy after laser therapy. This consisted of chemotherapy in five, surgery in two, and radiation therapy in one. Complications consisted of aspiration pneumonia in three patients, including one who developed a tracheoesophageal fistula, and one documented and two suspected perforations. Hospital stay averaged 5.4 days overall and 3.5 days in those treated with the single‐session techniques. This increased to 8.0 days in patients with proven or suspected perforations. Endoscopic laser therapy is a safe and effective method for palliating esophageal cancer.
Effects of electrocautery, CO2 laser, and contact Nd:YAG laser scalpel on the healing of intestinal incision
Authors: Puolakkainen Pauli , Brackett Kim , Sankar M. Y. , Joffe Steven , Schröder Tom 
Published: March 2007

AbstractLeakage after intestinal resection is a serious complication with a high mortality rate. A recent study claims that cutting the intestine with the CO2 laser improves the healing of intestinal anastomoses (Ferulano et al: Eur Surg Res 16:127–130, 1984). The present study was undertaken to analyze the effects of electrocautery, CO2 laser, and contact Nd:YAG laser on the healing of intestinal incisions.Fifteen piglets were used and the cutting and reanastomosing were performed by using all cutting methods in each animal in randomized order. Resection sites were 50 cm, 100 cm, and 150 cm distal to the ligament of Treitz. On the seventh day the bursting pressures were measured for each anastomosis. They were 172 ± 17 mmHg for normal bowel segment and 133 ± 12, 135 ± 40, and 139 ± 17 mmHg for electrocautery, CO2 laser, and Nd:YAG laser, respectively.There were no mortality, no anastomotic leaks, and no statistically significant differences in the bursting pressures, in histology, or in the healing of anastomotic sites, indicating that electrocautery, CO2 laser, and contact Nd:YAG laser scalpel can safely be used in the surgery of small intestine.
The contact Nd:YAG laser system in the treatment of bladder cancer: A preliminary report in 48 patients
Authors: Washida Hiroto , Watanabe Hideki , Sakagami Hiroshi , Sasaki Syoichi , Daikuzono Norio 
Published: March 2007

AbstractA synthetic contact sapphire endoprobe attached to the quartz fiber of a neodymium:yttrium aluminum garnet (Nd:YAG) laser had been used in the transurethral treatment of bladder tumors. A total of 68 operations have been carried out in 48 patients. The contact probe was placed directly into the tumor under direct vision. Using 15‐20 watts of laser energy, the tumor blanched and underwent necrosis. The technique was easy to apply, and bleeding was minimal. Damage to the ureteral orifice and ureter in the bladder wall at repeat cystoscopy appeared less than with conventional electrocautery or noncontact laser treatment. The technique of contact Nd:YAG laser surgery will have an important role in the transurethral treatment of bladder tumors.
Effects of varying argon ion laser intensity and exposure time on the ablation of atherosclerotic plaque
Authors: Strikwerda Sipke , Bott‐Silverman Corinne , Ratliff Norman B. , Goormastic Marlene , Cothren Robert M. , Costello Ben , Kittrell Carter , Feld Michael S. , Kramer John R. 
Published: March 2007

AbstractUsing continuous wave (CW) argon ion laser light, a total of 253 laser exposures of varying power (1.5, 3, 5, 8 or 10 W) and duration (20–1,333 ms) were delivered to four segments of human atheromatous aorta obtained at autopsy. Exposure conditions were controlled by using an optically shielded laser catheter that provided a 500 μm spot of light of known power. Two thresholds for consistently reproducible ablation could be defined–an intensity threshold at 25.5 W/mm2 and a fluence threshold at 3.2 J/mm2. Above threshold, a fluence of 5.1 J/mm2 was found to produce the most efficient ablation, ie, removed the greatest volume (mm3) per energy delivered (J) compared to other fluence levels employed (p < 0.0001). Between aortic segments, however, considerable variability in efficiency (mm3/J) was observed, possibly owing to different optical properties and/or plaque composition. Low‐intensity laser radiation produced inconsistent ablation and extensive coagulation effects to surrounding tissue. When a fluence of 5.1 J/mm2 was constructed with a high‐intensity laser beam and a short exposure time, consistent and efficient tissue removal resulted without histologic evidence of coagulation necrosis.
Comparison of different lasers in terms of thrombogenicity of the laser‐treated vascular wall
Authors: Ragimov Sergey E. , Belyaev Andrey A. , Vertepa Igor A. , Dolgov Vladimir V. , Furzikov Nicolay P. , Akchurin Renat S. , Repin Vadim S. , Trubetskoy Andrey V. 
Published: March 2007

AbstractThe thrombogenic properties of the laser‐treated vascular wall are reported as quantitatively assessed on the basis of 33 experiments with peripheral canine vessel segments. Three types of surfaces, namely, (1) intact, (2) mechanically de‐endothelized, and (3) postlaser, have been simultaneously exposed to platelet‐enriched plasma in a sequentially organized artificial circulation system. Then the adherent platelets have been counted on the treated surfaces, and the relative thrombogenicity index has been calculated according to the equation T = (A1 – Aint)/(Ad – Aint), where Aint, Ad, A1 = the adherent platelet counts on intact, mechanically de‐endothelized, and laser‐treated surfaces, respectively. The following lasers have been evaluated: (1) Nd‐YAG, 1,060 nm, continuous wave, 4 W; (2) argon‐ion, 480 and 514 nm and argon‐ion, 350 nm, continuous‐wave, 1 W and 400 nW, respectively; (3) excimer XeCl, 308 nm, pulsed, 30 mJ per pulse, repetition rate 100 Hz; and also (4) the laser‐heated metal probe (2 mm diameter, Trimedyne, Nd‐YAG) 1,060 nm, 8 W. The thrombogenicity index values obtained were 83 ± 7, 72 ± 8, 57 ± 9, 63 ± 7, and 82 ± 9%, respectively. The differences between these values were statistically insignificant. The data are suggestive of the essential requirement of, at least, anticoagulant therapy after laser angioplasty irrespective of the laser type.
New laser hysteroscope for neodymium‐YAG endometrial ablation
Authors: Baggish Michael S. 
Published: March 2007

AbstractA multichannel operating hysteroscope was developed for use with the Nd‐YAG laser. The telescopes measure 350 mm in length, with a 4 mm outer diameter (OD), and are available with 0° or 30° objectives. The operating sheath incorporates two isolated operating channels (2 mm OD) through which an Nd‐YAG quartz fiber and an aspiratory canula can be inserted simultaneously. The design of this instrument permits constant or intermittent aspiration of debris from the intrauterine milieu and very clear vision throughout the operative procedure. The entire cavity of the uterus may be flushed with the distending medium by injecting the liquid through the instillation channel and opening one of the two operating channels.
Long‐term investigations of laser‐assisted microvascular anastomoses with the 1.318‐μm Nd:YAG laser
Authors: Ulrich F. , Dürselen R. , Schober R. 
Published: March 2007

AbstractLaser‐assisted microvascular anastomoses can be performed with the most diverse types of laser (Dujovny et al: 4th Annu Gen Sci Meet LANSI, 1986; Godlewski et al: World J Surg 10:329‐333, 1986; Gomes et al: Rev Hosp Clin Fac Med Sao Paulo 37:255, 1982; Quigley et al: Laser Surg Med 5:357–367, 1985; Quigley et al: Lancet 1:334, 1985; Quigley et al: Neurosurgery 18(3):292–299, 1986; Jain: J Microsurg 1:436–439, 1980; Jain: Lancet 2:816–817, 1984; Krueger and Almquist: Lasers Surg Med 5:55, 1985; Neblett et al: Neurosurgery 19(6):914–934, 1986; Schober et al: Science 232:1421–1422, 1986; Ulrich et al: 2nd Annu Gen Sci Meet LANSI, 1984; Ulrich and Bock: Optoelectronics in Medicine, Spring‐Verlag 418–423, 1986). However, postoperative complications in the form of thromboses and aneurysmatic sacs could be detected in 7–29.8% in longitudinal investigations. By conversion of the beam geometry (1.3 μm Nd:YAG laser, 200 μm light conductor) and use of three concentrically applied 10.0 backstitch sutures in 25 end‐to‐end anastomoses of the common carotid artery of adult albino rats 0.8–1.2 mm in diameter, early and late complications could be markedly reduced (12%).
Combination of laser plus 5‐fluorouracil for the treatment of extensive genital condylomata acuminata
Authors: Krebs Hans‐B. 
Published: March 2007

AbstractAlthough laser is effective in the treatment of genital condylomata, patients with extensive lesions frequently require more than one treatment. The present study was undertaken to investigate whether the cure rate achieved by a single laser treatment could be improved by adding topical 5% 5‐fluorouracil (5‐FU). Twenty patients with extensive genital condylomata were treated with laser alone. Twenty patients comparable to the first group in age, number, size, and distribution of the condylomata were treated by laser and 5‐FU. The first application of 5% 5‐FU cream was carried out at the end of the laser treatment by the surgeon in the operating room. The patients were instructed to apply 5‐FU cream once weekly to the vulva and once every two weeks to the vagina by using an applicator filled to one‐third with 5‐FU cream. Seven patients (35%) without 5‐FU were found to have persistent condylomata at the first follow‐up examination eight to 12 weeks after the single laser treatment. Two additional patients were noted to have disease six and nine months after laser treatment. The combination of laser and 5‐FU failed in two cases (10%), both identified at the first visit. The difference is statistically significant (P <.025, chi‐square test). Two patients exposed to 5‐FU experienced chemical vulvitis. It is concluded that the combination of a single laser treatment and 5‐FU has acceptable side effects and results in a higher cure rate than a single laser treatment without 5‐FU.
Effects of different contact laser scalpels on skin and subcutaneous fat
Authors: Hukki Jyri , Krogerus Leena , Castren Maaret , Schroder Tom 
Published: March 2007

AbstractThe tissue effects of different Nd:YAG contact laser scalpels on pig skin and subcutaneous fat were studied using various power settings. Three different laser scalpels were tested: 0.2 mm nonfrosted (LR2), 0.6 mm nonfrosted (LR6), and 1.0 mm frosted (LRP10), using 3 different power settings (8 W, 14 W, 18 W). The tissue effects of a steel scalpel were used as reference. Incisions on pig loin (40/pig) were made at randomized sites. Specimens were taken at postoperative days 0 and 14. The depth of tissue damage was measured using a light microscope. The amount of time required for making each incision was recorded.Significant differences between the LR2 and the LR6 were observed in the skin at 2 weeks (P <.05) at all power settings used, indicating superiority of the smaller scalpel for use in skin incisions. The LRP10 did not cause more tissue damage than did the LR6 in any of the power settings used.In subcutaneous fat the smallest scalpel (LR2) caused significantly less tissue damage evident at 2 weeks postoperatively (P <.05) than did the other two laser scalpels, whereas the effects of the different power settings were minor.The incision time in skin decreased by more than 50% when the power was increased from 8 W to 18 W for all laser scalpels studied.
Prograde versus retrograde endoscopic laser therapy for the treatment of malignant esophageal obstruction: A comparison of techniques
Authors: Pietrafitta Joseph J. , Bowers Gary J. , Dwyer Richard M. 
Published: March 2007

AbstractThe prograde and retrograde approaches to the treatment of malignant esophageal obstruction with the Nd:YAG, or neodymium: yttrium, aluminum, garnet, laser are compared. With the prograde technique, tumor destruction procceds from the proximal to the distal tumor margin. In retrograde treatment, the endoscope is passed to the distal tumor margin so that the treatment can proceed in the reverse direction, thereby completing therapy in a single treatment session. This is usually accomplished by passage of a guide wire down the biopsy channel of the endoscope, tumor dilatation, and then passage of the endoscope over the guide wire to the distal tumor margin, where laser destruction is begun. Twenty nonrandomly selected patients with malignant esophageal obstruction were studied. The first ten patients were treated with the prograde technique, the next ten with the retrograde technique. The two groups were similar with respect to age, sex, and tumor histologies. Patients treated retrogradely had narrower pretreatment lumens (average 2.3 vs. 4.1 mm) as well as longer tumor lengths (average 8.9 vs. 4.8 cm). The posttreatment luminal diameters were similar for each group: 18.0 mm for prograde; 16.3 for retrograde. In the retrograde group, therapy was completed in fewer treatments (1.6 vs. 2.9) and over a shorter period of time (3.6 vs. 7.8 days), despite the longer tumor lengths. All patients in both groups were able to tolerate a regular diet at the completion of therapy. The complication rate was low in both groups. It is felt that the retrograde technique (single session therapy) is the preferred method because it allows more‐rapid treatment without increased complications and thereby shortens hospital stay and reduces hospital costs.
Preliminary evaluation of a pulsed 2.15‐μm laser system for fiberoptic endoscopic surgery
Authors: Treat Michael R. , Trokel Stephen L. , Reynolds R. David , DeFilippi Vincent J. , Andrew James , Liu Jenn Ying , Cohen Martin G. 
Published: March 2007

AbstractThere is a need for lasers that are compatible with fiberoptic endoscopes and that provide greater cutting precision than currently can be produced by the widely used Nd:YAG (1.06μm) laser. Recently available lasers that operate in the 2‐μm region fill this need. This laser light energy can be transmitted by low OH–silica fibers and has much less tissue penetration than radiation at 1.06 μm. We have been evaluating a prototype solid state laser system that produces pulses of 2.15 μm light that is delivered by a silica based fiberoptic delivery system with negligible transmission losses. This system is based on a thuliumholmium‐chromium doped YAG (Tm‐Ho‐Cr: YAG) rod that lases at 2.15 μm. The laser does not require cryogenic cooling, toxic gases, or custom utilities and should be practical in a clinical environment. In vivo animal testing of this laser confirms that it provides greater ablating precision than does the Nd:YAG laser at 1.06 μm.
Laser lithotripsy: A review of 20 years of research and clinical applications
Authors: Dretler Stephen P. 
Published: March 2007

AbstractFour new technologies have transformed the treatment of urinary calculi: electrohydraulic lithotripsy, ultrasonic lithotripsy, extracorporeal shock wave lithotripsy, and laser lithotripsy. Initial attempts to ablate urinary calculi by continuous wave CO2, ruby, and Nd‐YAG lasers failed because of excess thermal injury and inability to pass the laser energy via a flexible fiber. Basic laboratory studies then demonstrated that short pulsed laser energy absorbed by the calculus resulted in fragmentation. The parameters that produced optimal urinary calculus fragmentation were found using the flashlamp pumped tunable dye laser, with the following parameters: wavelength: 504 nm; pulse duration: 1 μsec; fiber: 250 micro silica‐coated quartz; repetition: 5–20 Hz. Use of pulsed dye laser caused no tissue damage. The mechanism of fragmentation is light absorption, plasma development, and repetitive acoustic shock wave action with resultant fragmentation. The techniques for application of laser to calculi have been successful, and new, miniature instruments have been developed. Laser lithotripsy is a successful method for fragmenting ureteral calculi. The small caliber of the laser fiber makes this method useful for treating calculi in narrow, tortuous ureters; impacted calculi; distal calculi in ureters that cannot be dilated, via the percutaneous route for stones in calyces or impacted in the upper ureter. Investigations are continuing to optimize fragmentation of harder calculi and to use laser fragmentation within the kidney. Laser lithotripsy may also be used to fragment biliary calculi.
Laser balloon angioplasty: Effect of exposure duration on shear strength of welded layers of postmortem human aorta
Authors: Jenkins Ronald D. , Sinclair I. Nigel , Anand Raj K. , James Leslie M. , Spears J. Richard 
Published: March 2007

AbstractLaser Balloon Angioplasty (LBA) is a technique that may improve the results of balloon angioplasty by thermally sealing arterial dissections and reducing elastic recoil. To define the relationship between laser‐exposure duration and the strength of thermal welds made between separated layers of arterial wall, 360 1‐cm discs of human postmortem aorta were lased for six different exposure intervals at three different temperature ranges, comparing shear strength of thermal welds in the different groups. Twenty discs were lased to achieve plateau adventitial temperatures of 95°C–104°C (group A), 105°C–114°C (group B), or 115°C–124°C (group C) at each of the exposure periods (5, 10, 15, 20, 25, and 30 sec). A 400‐μm fiberoptic coupled to a 1.06 μm continuous wave neodymium:YAG laser was placed perpendicularly 8 mm above the luminal surface of each disc, which had been split midway between the intimal and adventitial surface and reapposed. Mean laser energy ranged 78–378 J delivered in a decremental stepwise fashion to achieve quickly and maintain the target plateau tissue temperature. Mean weld strength increased in relation to both achieved tissue temperature and laser‐exposure duration, with at least 10 sec necessary, at temperatures greater than 95°C, for reliable thermal welding. Laser exposure for greater than 20 sec provided no statistical increment in weld strength. In the anticipated clinical performance of LBA, these data suggest that when thermal fusion of disrupted arterial tissues is desired, a laser‐exposure duration of 10–20 sec is optimal.
Laser instrumentation: A microtenaculum for laser tissue fusion
Authors: White John V. 
Published: March 2007

AbstractPrecise tissue apposition and edge eversion are essential for tissue fusion with the CO2 laser. A microtenaculum has been designed to accomplish this without the placement of horizontal mattress stay sutures. This instrument permits tissue orientation and approximation for primary laser fusion as well as for the repair of small gaps present after initial welding.