bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of thermal cooling mechanisms for laser application to teeth
Authors: Miserendino Leo J. , Abt Elliot , Wigdor Harvey , Miserendino Catherine A. 
Published: March 2007

AbstractExperimental cooling methods for the prevention of thermal damage to dental pulp during laser application to teeth were compared to conventional treatment in vitro. Pulp temperature measurements were made via electrical thermistors implanted within the pulp chambers of extracted human third molar teeth. Experimental treatments consisted of lasing without cooling, lasing with cooling, laser pulsing, and high‐speed dental rotary drilling.Comparisons of pulp temperature elevation measurements for each group demonstrated that cooling by an air and water spray during lasing significantly reduced heat transfer to dental pulp. Laser exposures followed by an air and water spray resulted in pulp temperature changes comparable to conventional treatment by drilling.Cooling by an air water spray with evacuation appears to be an effective method for the prevention of thermal damage to vital teeth following laser exposure. © 1993 Wiley‐Liss, Inc.
Beta carotene uptake into atherosclerotic plaque: Enhanced staining and preferential ablation with the pulsed dye laser
Authors: Mitchell David C. , Prince Martin R. , Frisoli Joan K. , Smith Roy E. , Wood Richard F. M. 
Published: March 2007

AbstractThe yellow color of atherosclerotic plaque is due to the presence of carotenoids, which absorb light between 430–530 nm and account for the preferential ablation of plaque by the pulsed dye laser operating at 480 nm. This study was designed to examine tissue uptake of β‐carotene and the effect of uptake on arterial plaque ablation. Forty‐two atherosclerotic NZW rabbits were given intravenous β‐carotene at a dose of 40 mg/kg, twice weekly and killed between 1 hour and 28 days after the initial injection. β‐carotene was not detected in control specimens but was significantly greater in plaque than in normal wall at all time points following β‐carotene injection (P < 0.04 Mann Whitney U test). The ablation threshold was significantly lower in β‐carotene treated plaque than in untreated plaque or normal arterial wall (P < 0.01, Fisher's exact test). In this model β‐carotene is preferentially taken up into arterial plaque, resulting in increased absorption of laser radiation at 480 nm and enhanced tissue ablation. © 1993 Wiley‐Liss, Inc.
Improved excimer laser photorefractive keratectomy system
Authors: van Saarloos Paul P. , Constable Ian J. 
Published: March 2007

AbstractAn improved 193 nm excimer laser photorefractive keratectomy system is described here. The delivery system was optimised to produce a smooth keratectomy bed, to minimise the healing response, and to reduce the regression of the refractive result. A spatial filtering system was used to smooth the energy distribution within each pulse, and the iris was adjusted for every pulse, to eliminate steps and other irregularities from the keratectomy profile. An image rotator was used to average out any remaining non‐uniformities in the energy distribution. The results from the first 39 eyes treated with this laser system with a maximum follow‐up of 18 months, are summarised. No epithelial healing problems were noticed, and little or no loss of corneal clarity was noted at any stage during healing. Twenty of the keratectomy procedures were normally sighted myopic corrections, with a maximum follow‐up of 5 months. Minimal regression of the refractive correction was seen during the first 8 weeks. © 1993 Wiley‐Liss, Inc.
Fine structure of zonal changes in experimental Nd:YAG laser–induced interstitial hyperthermia
Authors: Schober Ralf , Bettag Martin , Sabel Michael , Ulrich Frank , Hessel Stefan 
Published: March 2007

AbstractInterstitial thermotherapy using Nd:YAG‐laser induced hyperthermia is a new stereotactic method for the treatment of brain tumors in poorly accessible regions. To provide a basis for the underlying tissue alterations, we have analyzed the spatial and temporal pattern of interstitial laser hyperthermia lesions in the normal rat brain by histological, immunohistochemical, and electron microscopical methods. The acute changes corresponded to the temperature gradient surrounding the laser probe and showed a distinct zonal architecture. Membrane destruction on a cellular and subcellular level appears to be of major significance in the pathogenesis of the laser lesion. The tissue reaction followed the course known for coagulation necrosis and resulted in a well‐defined defect. These results, although limited by the choice of the experimental model, may be helpful in the interpretation of images obtained in future applications of interstitial thermotherapy. © 1993 Wiley‐Liss, Inc.
Effects of plume produced by the Nd:YAG laser and electrocautery on the respiratory system
Authors: Wenig Barry L. , Stenson Kerstin M. , Wenig Bruce M. , Tracey Diana 
Published: March 2007

AbstractSprague‐Dawley rats were exposed to Nd:YAG laser exhaust (contact and noncontact) as well as to electrocautery exhaust passed through smoke evacuation filters. Exposure periods for each group were equal and increasing in time. Histologic analysis revealed alveolar congestion and emphysematous changes in all modes. Controls exhibited similar change but to a milder degree. It appears that any plume produced by lasers or electrosurgical devices produces pathologic change in rat lungs and that effective smoke evacuation will help control these effects. © 1993 Wiley‐Liss, Inc.
Laser vaporization of Peyronie's plaques
Authors: Costello Russell T. 
Published: March 2007

AbstractA series of four cases of surgical excision or vaporization of Peyronie's plaques using the Neodynium/Yag laser is presented. This technique would appear to decrease the need for grafting procedures with minimal blood loss. It results in straight erections without shortening the penis. © 1993 Wiley‐Liss, Inc.
Characterization of pulsed‐dye laser‐mediated vasodilatation in a rabbit femoral artery model of vasoconstriction
Authors: Schwengel Robert H. , Gregory Kenton W. , Hearne Steven E. , Scott Helen J. , Beauman Glenn J. , Mergner Wolfgang J. , Caplin John L. , Ziskind Andrew A. 
Published: March 2007

AbstractVasoconstriction is a clinical problem associated with invasive vascular procedures, microvascular reconstruction and subarachnoid hemorrhage. We sought to characterize the ability of pulsed‐dye laser irradiation to reverse and prevent vasoconstriction in an anesthetized rabbit model of surgically and pharmacologically induced vasoconstriction.Five groups of experiments were performed to study the effect of pulsed‐dye laser irradiation delivered through a 320 μm core ball‐tip fiber into the femoral artery. The studies demonstrated that pulsed‐dye irradiation can reproducibly cause vascular dilatation. The zone of vasodilatation propagated equally proximal and distal to the site of irradiation within the vessel. When saline was infused into the vessel to replace flowing blood during delivery of laser irradiation, no significant vasodilatation occurred. After laser irradiation reversed surgical and pharmacologic vasoconstriction, the vessel was resistant to further pharmacologic Vasoconstriction. This resistance to pharmacologic vasoconstriction did not occur if the vessel was pharmacologically predilated before delivery of laser irradiation. Pathologic analysis of the vessels revealed endothelial damage and mild to moderate medial necrosis, most significant at the site of energy delivery.These studies provide characterization of pulsed‐dye laser‐mediated vasodilatation in an in vivo model. Delivery of pulsed‐ dye laser energy has potential clinical application and warrants further investigation. © 1993 Wiley‐Liss, Inc.
Effect of multidrug‐resistant P‐glycoprotein gene expression on chloroaluminum tetrasulfonate phthalocyanine concentration
Authors: Frazier Donita L. , Barnhill Mary Ann , Lu Xiaochen , Jones Emily , Niemeyer Glenn , Mishu Leslie , Lothrop Clint D. 
Published: March 2007

AbstractThe effect of multidrug‐resistant P‐glycoprotein gene expression (MDR1) in 3T3 cells on cellular concentrations and cytotoxicity induced by the photodynamic agent chloroaluminum tetrasulfonate phthalocyanine (AISPc) was evaluated. 3T3 cells transfected with a retroviral vector expressing human MDR1 cDNA were resistant to colchicine. Resistant cells incubated with daunomycin accumulated only 40–50% of the quantity of daunomycin accumulated in control cells. Resistant cells incubated with daunomycin in the presence of verapamil had intracellular daunomycin concentrations approximately equal to control cells without verapamil. When these MDR1 3T3 cells were incubated with AISPc, cellular concentrations of AISPc did not differ between cells resistant to colchicine and those that were not. Similarly, there was little difference in cytotoxicity demonstrated by 51Cromium release in the two cell lines exposed to AISPc and light (675 nm; 6 J/cm2). This study suggests photodynamic therapy using AISPc may be a useful treatment modality for tumors in which the MDR1 P‐glycoprotein confers resistance to cancer chemotherapeutics. © 1993 Wiley‐Liss, Inc.
Preparation of human albumin solder for laser tissue welding
Authors: Poppas Dix P. , Choma Theodore J. , Rooke Christopher T. , Klioze Scott D. , Schlossberg Steven M. 
Published: March 2007

AbstractPrevious studies have demonstrated that the addition of a protein solder to augment the laser tissue weld significantly improves postoperative results. Herein we describe a method for the preparation of human albumin for use as a laser tissue solder. We also review the brief history of laser tissue solders and discuss recent advances using this technology. © 1993 Wiley‐Liss, Inc.
Dose and temporal parameters in delaying injured optic nerve degeneration by low‐energy laser irradiation
Authors: Rosner Mordechai , Solomon Arieh , Assia Ehud , Belkin Michael , Caplan Michael , Cohen Shmuel , Duvdevani Revital , Schwartz Michal 
Published: March 2007

AbstractLow‐energy laser irradiation has been reported to postpone the degenerative processes in crushed optic nerves of rats, which are part of the nonregenerable mammalian central nervous system. In the present study, we evaluated the optimal irradiation parameters for this purpose. Optic nerves of 141 rats were subjected to crush injury and then irradiated through the eye, starting at different points of time before or after the injury, for different durations and periods, using various intensities of either heliumneon laser or noncoherent infrared light (904 nm). The effect was evaluated by measurements of the compound action potentials of the nerve segments between the site of injury and the optic chiasm. The compound action potential amplitude of the crushed nonirradiated nerves, as measured 2 weeks after the injury, was found to be 0.51 ± 0.30 mV, in contrast to 3.10 ± 1.03 mV measured in 232 normal nerves. Irradiation with a 10.5 mW helium‐neon laser for 2 and 3 min once a day for 14 consecutive days resulted in maximal preservation of action potentials (1.78 ± 0.72 and 1.95 ± 0.71 mV, respectively). Irradiations beginning immediately prior to the injury were as effective as irradiations beginning soon after it. Irradiations for longer than 3 min or twice a day aggravated the damage. Noncoherent infrared light was ineffective or adversely affected the injured nerves. Our experiments suggest that optimal delay of posttraumatic optic nerve degeneration in rats is attainable with 10.5 mW helium‐neon laser irradiations for 2 or 3 min once a day for 14 consecutive days. © 1993 Wiley‐Liss, Inc.
In vitro evaluation of ablation parameters of normal and fibrous aorta using smooth excimer laser coronary angioplasty
Authors: Xie Dao Yin , Hassenstein Stefan , Oberhoff Martin , Hanke Hartmut , Baumbach Andreas , Hohla Kristian , Haase Karl Konstantin , Karsch Karl Rüdiger 
Published: March 2007

AbstractA modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave‐ and cavitation‐induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley‐Liss, Inc.
Ureteroscopic management of transitional cell carcinoma of the ureter using the neodymium:YAG laser
Authors: Kaufman Ronald P. , Carson Culley C. 
Published: March 2007

AbstractUreteroscopy offers an extension of endoscopic diagnosis and treatment to upper urinary tract malignancy. Combination of ureteroscopy and the Nd:YAG laser permits accurate and effective treatment of ureteral neoplasms. Nine highly selected patients, six males and three females, were treated with low grade papillary transitional cell carcinomas of the ureter with at least 24 months follow‐up. Follow‐up cytology and IVP have indicated no evidence for disease recurrence between the follow‐up periods and minimal morbidity to the ureteroscopy and laser treatment. © 1993 Wiley‐Liss, Inc.
Prostatectomy by transurethral balloon Laserthermia™ (PROSTALASE™) in the canine
Authors: Suzuki Takanori , Kurokama Kohei , Yamanaka Hidetoshi , Long Liong Men , Daikuzono Norio 
Published: March 2007

AbstractProstatectomy by transurethral balloon Laserthermia (PROSTA‐LASE™) was performed in a canine model. This balloon device monitored by transrectal ultrasound can cylindrically irradiate with a laser beam. The treatment was performed in 8 canines using 15 watts for 20 minutes at 60°C at a 5 mm depth of the prostate from the urethral surface. Immediately following the laser therapy, an area of coagulation necrosis was observed around the urethra to a depth of 4–5 mm from the surface. After 1 week, cavitation formation was seen in 3 or 4 canines by ultrasound, and the urethral reepithelialization was shown in 1 of 2 canines. After 2 weeks, cavitation formation was observed in both canines, and the urethra was completely reepithelialized in one canine. There was no tissue damage in the bladder neck of urethral sphincter and no urinary incontinence in any animal. This system is thought to be simple and, satisfactorily performed, is an effective transurethral prostatectomy. © 1994 Wiley‐Liss, Inc.
Use of the holmium:YAG (Ho:YAG) laser for treatment of superficial bladder carcinoma
Authors: Johnson Douglas E. 
Published: March 2007

AbstractThis is the first North American report describing the use of the holmium:YAG (Ho:YAG) laser to treat patients with superficial bladder carcinoma. Fifteen patients, with a total of 52 recurrent superficial bladder tumors, underwent endoscopic laser photoablation of their lesions. No intraoperative or delayed complications occurred. At follow‐up cystoscopy performed 3 months after lasing, four patients (27%) were without disease; eight patients (53%) had out‐of‐field recurrences; and three patients (20%) were classified as having in‐field recurrences. We conclude that using the Ho:YAG for endoscopic treatment of patients with superficial bladder tumors is both feasible and clinically useful and that the lack of perceived pain or discomfort during lasing, as well as the lack of need for an in‐dwelling urethral catheter, makes it advantageous for selected patients over conventional electroresection techniques. © 1994 Wiley‐Liss, Inc.
Tissue optical property measurements: Overestimation of absorption coefficient with spectrophotometric techniques
Authors: Torres Jorge H. , Welch Ashley J. , Çilesiz Inci , Motamedi Massoud 
Published: March 2007

AbstractThis study examines the validity of optical property measurements by comparing surface temperatures rises predicted by a well‐tested mathematical model with temperatures measured experimentally during laser irradiation. Analysis is based on the early temperature response that is proportional to the absorption coefficient. The results of the investigation suggest that values for tissue absorption coefficient can be greatly overestimated when current Spectrophotometric techniques are used. This seems especially true when a broad light beam and a low port‐to‐beam‐size ratio are used for transmission and reflection measurements with an integrating sphere. © 1994 Wiley‐Liss, Inc.
Interstitial laser prostatectomy
Authors: Johnson Douglas E. , Cromeens Douglas M. , Price Roger E. 
Published: March 2007

AbstractSerial gross and histopathologic examinations of the prostate following interstitial laser prostatectomy in the canine model demonstrated distinct zonal thermal changes around the entire active area of the interstitial thermal therapy (ITT) fiber. A large, well‐demarcated area of acute coagulative necrosis immediately surrounded each fiber tract; beyond that were a prominent narrow peripheral zone of marked tissue disruption and an outer zone of hemorrhage. Liquefaction within these coagulative areas was evident within 24 hours, and by 4 days, each lobe of the prostate contained an irregular cavity that became lined by normal‐appearing transitional epithelium and that, by 5 weeks, communicated with the prostatic urethra. These postmortem pathologic observations, similar to findings previously reported following transurethral laser prostatectomy, suggest that interstitial laser thermal therapy may provide an additional means for treating benign prostatic hyperplasia in men. © 1994 Wiley‐Liss, inc.
Factors affecting size and configuration of neodymium:YAG (Nd:YAG) laser lesions in the prostate
Authors: Fournier George R. , Narayan Perinchery 
Published: March 2007

AbstractLaser surgery for benign prostatic hypertrophy is a clinical reality and a promising alternative to traditional transurethral electroresection of the prostatic adenoma (TURP). Current methods of laser prostatectomy involve coagulation of prostate tissue using a quartz side‐firing fiber that redirects a Nd:YAG laser beam at 70–90° most commonly by means of a metal reflector. In this communication we describe a method of tissue evaporation using a side‐firing fiber that avoids use of a metal reflector by means of internal reflection. It is relatively resistant to damage when coming in contact with tissue. By placing the fiber tip in direct contact with tissue, much larger lesions are created because of more efficient energy transfer resulting in rapid evaporation of tissue under water. In prostate surgery, this phenomenon of accelerated evaporation can be used to bloodlessly evaporate adenomatous tissue creating a defect that resembles that of a traditional TURP. © 1994 Wiley‐Liss, Inc.
Enhanced ArF laser absorption in a collagen target under ablative conditions
Authors: Ediger M. N. , Pettit G. H. , Hahn D. W. 
Published: March 2007

AbstractThe time‐resolved transmission of collagen targets during ArF excimer laser ablation has been measured. The transmitted excimer pulse measurements demonstrate enhanced media attenuation that is a nonlinear function of incident laser fluence. Forward scattering of the transmitted pulse has been assessed to be a negligible contributor to the observed phenomena. Results of pump/probe interrogation of the ablation site indicate that the onset of enhanced attenuation occurs on the time course of the ablating laser pulse and persists for times on the order of hundreds of microseconds. © 1994 Wiley‐Liss, Inc.
Effect of low‐intensity argon laser irradiation on mitochondrial respiration
Authors: Morimoto Yuji , Aral Tsunenori , Kikuchi Makoto , Nakajima Shinji , Nakamura Haruo 
Published: March 2007

AbstractWe studied influences of low‐intensity argon laser irradiation at various wavelengths on mitochondrial respiration in vitro. Isolated guinea pig liver mitochondria were suspended in an isotonic buffer solution (pH 7.4,37°C). The mitochondrial suspension was introduced into a constant temperature reaction chamber in which an irradiation fiber, a thermocouple, an oxygen electrode, and a stirrer were installed. Under respiratory conditions of state 4, state 3, and uncoupled respiration, mitochondrial oxygen consumption was measured during low‐intensity argon laser irradiations at 351nm, 458 nm, and 514.5 nm. The 351 nm and the 458 nm irradiations at 200 mW inhibited uncoupled respiration by 19% and 11%, respectively, and the irradiation at 351 nm inhibited state 3 respiration as well by 10%. In contrast, the 514.5 nm irradiation enhanced both state 3 and uncoupled respiration by 6–7%. Temperature reference experiments indicated that the thermal effect alone could not account for the effects of laser irradiation on mitochondrial oxygen consumption. These results suggest that the 351 nm and the 458 nm laser irradiation may injure the mitochondrial inner membrane, while the 514.5 nm laser irradiation may slightly promote the rate of ATP synthesis. © 1994 Wiley‐Liss, Inc.
Effect of the dynamic optical properties of water on midinfrared laser ablation
Authors: Walsh Joseph T. , Cummings Joseph P. 
Published: March 2007

AbstractWater is a primary tissue chromophore in the midinfrared. Absorption of midinfrared radiation by water is a function of temperature and pressure, both of which rise rapidly during an ablative laser pulse. Data show that the absorption coefficient of water changes, by as much as two orders of magnitude, during a high‐irradiance laser pulse. We present an ablation model that is fundamentally based upon Beer's Law but considers changes in the absorption coefficient. The model predicts that Er:YAG laser cuts will be deeper than Er:YSGG laser cuts; an opposite prediction would be made based upon the static, low‐intensity absorption coefficient of water. The results of in vitro ablation of skin confirm that the dynamic optical properties of tissue need to be considered in the understanding of laser ablation as well as the design, manufacture, use, and regulation of clinical laser systems. © 1994 Wiley‐Liss, Inc.
Ex vivo optical properties of human colon tissue
Authors: Marchesini Renato , Pignoli Emanuele , Tomatis Stefano , Fumagalli Sabrina , Sichirollo Adele E. , Palma Silvana Di , Fante Marko Dal , Spinelli Pasquale , Croce Anna C. , Bottiroli Giovanni 
Published: March 2007

AbstractUsing a spectrophotometer equipped with an internal integrating sphere, the absorption (μa) and the reduced scattering (μs′) coefficients of ex vivo human colon tissues were evaluated from reflectance and transmittance measurements. μa and μs′ varied from 47.7 to 1.0 cm−1 and from 14.2 to 6.2 cm−1, respectively, on passing from 300 nm to 800 nm. These results can be used to estimate the optical penetration depths when photodynamic therapy or light‐induced fluorescence procedures are used.