bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and experimental in vivo validation of mathematical modeling of laser coagulation
Authors: Beacco C. M. , Mordon S. R. , Brunetaud J. M. 
Published: March 2007

AbstractMost clinical procedures using the laser are based on thermal laser‐tissue interactions. The treatment often consists of inducing damage of given degree and extent by heating the tissue. The aim of this study was to develop a model called HELIOS. The ability of HELIOS to predict thermal coagulation was evaluated by comparison with in vivo experimental results. Conversion of laser light in tissue was studied using the beam‐broadening model. Temperature was described by the heat conduction equation solved using the finite difference method. The tissue dena‐turation was modeled by the Henriques equation leading to the determination of the damage coefficient ω. For a given set of laser and tissue parameters, HELIOS makes a graphic representation of coagulation necrosis and temperature evolution in tissue. HELIOS was validated by experimental studies in vivo on rat liver using a CW Nd:YAG laser, a CO2laser, and an argon laser. For given sets of laser parameters, temperature measurements were performed using an infrared camera. Histological examinations were carried out on samples to quantify the depth of coagulation necrosis. Experimental data obtained in vivo were compared with those calculated using HELIOS and similar sets of parameters. The difference between the predicted temperature evolution on tissue surface and that measured by the infrared camera was < 5°C in all cases. The difference between the predicted coagulation necrosis depth and the corresponding experimental one was < 10%. In conclusion, HELIOS allows good prediction of tissue temperature and coagulation necrosis. © 1994 Wiley‐Liss, inc.
Intraocular microsurgery with a picosecond Nd:YAG laser
Authors: Lin Charles P. , Weaver Yaffa K. , Birngruber Reginald , Fujimoto James G. , Puliafito Carmen A. 
Published: March 2007

AbstractWe investigated the use of picosecond Nd:YAG laser pulses for intraocular microsurgery. With a pulse duration of 100 picoseconds, only 70 μJ of pulse energy is required to consistently produce optical breakdown in the deep vitreous. This pulse energy is nearly two orders of magnitude less than the typical pulse energies used in conventional (nanosecond) photodisruptors. The reduced pulse energy results in a smaller zone of tissue damage, an important consideration when operating close to the retina or other sensitive ocular structures. Efficient cutting action is achieved by applying multiple pulses at a moderately high repetition rate of 50–200 Hz. An in vitro model was developed to assess axial confinement of picosecond photodisruption. In vivo vitreous membrane surgery was performed in experimental rabbit eyes to demonstrate a potential clinical application of picosecond laser—induced optical breakdown. © 1994 Wiley‐Liss, inc.
Dynamics of shock waves and cavitation bubbles generated by picosecond laser pulses in corneal tissue and water
Authors: Juhasz Tibor , Hu Xin H. , Turi Laszlo , Bor Zsolt 
Published: March 2007

AbstractTime‐resolved flash photography was used to investigate the dynamics of shock waves and cavitation bubbles generated by picosecond optical breakdown in bovine corneal tissue and water. A picosecond Nd:YLF laser was employed. A rapid decay of the shock waves was observed in both materials, with similar temporal characteristics, indicating that water serves as a good model for shock wave studies. In contrast, differences in the cavitation bubble dynamics were found between cornea and water, which are related to differences in the mechanical and thermal properties of the two media, suggesting that water should not be used to model cavitation dynamics in cornea. The experimental results also suggest that the efficiency of intrastromal ablation may be increased by using short pulses and moderate pulse energies in order to avoid the creation of large cavitation bubbles. The experiment indicates that the optimum laser repetition rate for intrastromal ablation is between 1 and 5 kHz. © 1994 Wiley‐Liss, Inc.
Determination of efficient parameters for argon laser‐assisted anastomoses in rats: Macroscopic, thermal, and histological evaluation
Authors: Martinot V. L. , Mordon S. R. , Mitchell V. A. , Pellerin P. N. , Brunetaud J. M. 
Published: March 2007

AbstractThe aim of this study was to determine efficient parameters for an argon laser (spot diameter = 200 μm) to obtain and reproduce vessel anastomoses. It was performed in two groups of Wistar rats. In the first group (89 Laser impacts on 10 carotids), the fluence was continuously adjusted from 30 to 3,000 J/cm2 in order to determine efficient sets of parameters (power from 90–200 mW, pulse duration from 0.1 to 5 seconds, pulsed or continuous mode). In the second group, 30 end‐to‐end carotid anastomoses were performed. The results were evaluated by macroscopic thermal, and histological studies. The second group proved the efficiency of the selected parameters. Vessel welding was obtained with 100 mW, 3 seconds, continuous mode (fluence = 950 J/cm2, irradiance = 320 W/cm2) for a mean temperature of 77°C corresponding to collagen denaturation. In the second group the patency rate was 93% (28/30) with three pseudo‐aneurisms and two thromboses. Histological studies noted slight modifications of the media. © 1994 Wiley‐Liss, Inc.
Comparison of laser vascular welding, interrupted sutures, and continuous sutures in growing vascular anastomoses
Authors: Chikamatsu Eiji , Sakurai Tsunehisa , Nishikimi Naomichi , Yano Takashi , Nimura Yuji 
Published: March 2007

AbstractBackground and Objectives: The argon laser‐assisted vascular anastomosis may solve the problems of conventional sutured anastomosis, such as vascular stenosis and arrest of growth owing to a foreign‐body reaction to suture material.Study Design/Materials and Methods: Twelve argon laser‐assisted vascular anastomoses, seven conventional anastomoses with interrupted sutures, and five conventional anastomoses with continuous sutures were performed in 12 young mongrel dogs.Results: Five months later, the external diameter at the anastomosis had increased 70.5% in the laser group, 67.0% in the interrupted suture group, and 22.9% in the continuous suture group. Histological examination of the laser‐assisted anastomoses showed almost complete healing, with no granulomatous response around the anastomotic site. In the interrupted suture group, marked scaring and foreign body reactions were observed on the vessel wall at the site of the anastomosis. The continuous suture group showed more remarkable disorientation of the vascular layer and intimal hyperplasia than the interrupted suture group.Conclusion: Vascular anastomosis using the argon laser offers advantages over the conventional procedure in growing vessels.
Evaluating the role of photodynamic therapy in the management of pancreatic cancer
Authors: Moesta K. Thomas , Schlag Peter , Douglass Harold O. , Mang Thomas S. 
Published: March 2007

AbstractBackground and Objective: Cancer of the pancreas constitutes one of the major causes of cancer related death throughout the world. A 5‐year survival rate of only 2% and a maximum of 20 months median survival in multi modality treatment studies dealing with the most favorable patients only, has been demonstrated. This review analyzes the principal treatments and available experimental data in view of a clinical application of photodynamic therapy (PDT) for the treatment of pancreatic cancer.Study Design/Materials and Methods: On the basis of published results, we examined the palliation of pancreatic cancer by chemotherapy alone; radiation alone and multimodality schedules (radiation and chemotherapy). Radical tumor resection was examined as attempted curative treatment.Results: In reported therapeutic procedures, palliative or potentially curative, median survival was below 2 years. The GTSG reported survival time increases from 10.9 to 21.0 months when surgery is followed by adjuvant chemotherapy and radiation. This combination postoperatively does not increase mortality, but adds 30% morbidity. Photodynamic therapy has been demonstrated in preclinical studies to have a selective effect on malignant versus the normal pancreas.Conclusion: PDT is highly effective in eliciting the destruction of experimental pancreatic tumors with the lack of significant effect on the normal pancreas. The poor prognosis for patients with this disease, especially those patients with advanced disease, warrants closer examination of PDT for the treatment of pancreatic cancer.
Laser‐induced fluorescence: III. Quantitative analysis of atherosclerotic plaque content
Authors: Yan Wei‐Dong , Perk Masis , Chagpar Anees , Wen Yue , Stratoff Sharon , Schneider Wolfgang J. , Jugdutt Bodh I. , Tulip John , Lucas Alexandra 
Published: March 2007

AbstractBackground and Objective: Laser‐induced fluorescence (LF) spectroscopic analysis of the chemical composition of atherosclerotic plaque was examined.Study Design/Materials and Methods: The intima of 18 dog aortas was injected with chemical compounds found in atherosclerotic plaque. Spectra were recorded in air prior to and after injection of collagens I, III and IV, elastin, cholesterol, triglyceride, and β‐nicotinamide adenine dinucleotide (NADH).Results: Significant changes in LF intensity were detected after injection of collagens I and III, cholesterol and elastin in thoracic aorta (P < 0.001), but not with triglyceride or NADH. Minor changes were detected in abdominal aorta. Multiple regression analysis of LF intensity ratios demonstrated a clear correlation with the quantity of injected collagens I (R2 = 0.90–0.99) and III (R2 = 0.84–1.0), cholesterol (R2 = 0.72–0.76), and triglyceride (R2 = 0.68–0.80) in both thoracic and abdominal aorta. The correlation between LF and atherosclerotic plaque composition was confirmed in a rooster model of atherosclerosis where multiple regression analysis predicted the measured aortic cholesterol (R2 = 0.78) and triglyceride content (R2 = 0.96).Conclusions: (1) Fluorescence spectra recorded from dog aorta were significantly altered by injection of collagens I and III, cholesterol, and elastin. (2) LF may allow quantitative assessment of plaque chemical content. © 1995 Wiley‐Liss, Inc.
Laser safety
Authors: Sliney David H. 
Published: March 2007

AbstractSafetyhas always been an important aspect of any laser application in surgery and medicine. In any review of the laser surgery literature, several issues continue to dominate. These issues include: wearing eye protectors, dealing with the plume of vaporized tissue, and controlling potential fire hazards. No one denies that lasers can pose a serious hazard to the eye, but the decision to wear eye protectors in all procedures has been frequently questioned. The degree of effort needed to minimize the very serious risk from chronic breathing of vaporized tissue also requires judgment. Aside from a few eye injuries from a laser beam exposure, most serious accidental injuries (and even deaths) reported to date from the laser beam itself can be traced to the ignition of surgical drapes and airway tubes. © 1995 Wiley‐Liss, Inc.
Low intensity laser therapy: Still not an established clinical tool
Authors: Basford Jeffrey R. 
Published: March 2007

AbstractThe surgical, ophthalmological, and dermatological applications of high power lasers are well known and easily understood. What is neither as well known nor as easily understood is that lasers at powers that are orders of magnitude smaller have also been used in the laboratory and clinic for nearly 30 years to modulate cell function, lessen pain, and accelerate healing of soft tissue injuries. This article analyzes the rationale of this approach, examines the utility of laser therapy in its most common clinical applications, reviews and synthesizes the findings, and concludes that although laboratory findings seem authentic, clinical utility remains unestablished. © 1995 Wiley‐Liss, Inc.
Pigmentation‐dependent side effects to copper vapor laser and argon laser treatment
Authors: Hædersdal Merete , Wulf Hans Christian 
Published: March 2007

AbstractBackground and Objective: Melanin is a limiting factor for obtaining beneficial results in dermatological treatment of vascular malformations. The aim of our study was to establish a relation between pretreatment skin pigmentation and the occurrence of side effects.Study Design/Materials and Methods: Thirteen human volunters selected to have a varying degree of skin pigmentation were laser‐treated on the inside of the brachium with an argon laser (AL, 488 nm and 514.5 nm) and a copper vapor laser (CVL, 578 nm), both connected to a Hexascan. Total exposure areas were 1.26 cm2 and beam diameters were 1 mm. Three intensities were used, 0.7, 1.0, and 1.3 W. Pulse duration was 200 ms, resulting in fluences of 17.8, 25.5, and 33.1 J/cm2. Pretreatment skin pigmentation was objectified by skin reflectance measurements.Results: At 1, 2, and 6 months after laser treatment, significant correlations were demonstrated between pretreatment skin pigmentation and laser‐induced pigmentary changes and scar formation. At the 6‐month assessment, the AL induced significantly higher scores of clinically evaluated scar formation as compared with the CVL (1.0 and 1.3 W/spot) and tended to induce higher clinical scores of pigmentary changes (not significant, ns).Conclusions: We recommend skin pigmentation to be taken into consideration in dermatological laser treatment of vascular malformations. © 1995 Wiley‐Liss, Inc.
Effects of Nd:YAG laser on wound healing processes: Clinical and immunohistochemical findings in rat skin
Authors: Romanos George E. , Pelekanos Stavros , Strub Jörg‐Rudolf 
Published: March 2007

AbstractBackground and Objective: The clinical effects of the Nd:YAG laser in the rat skin as well as alterations of the extracellular matrix during healing were presented in this study.Study Design/Material and Methods: This study evaluated the clinical effects of the Nd:YAG laser used with different energy parameters (low energy: 1.75 W and 20 pps / high energy: 3.0 W and 30 pps) in a duration 20–40 s in rat skin. Control incisions were performed with a scalpel blade. Rat skin incisions were examined over a period of 28 days by clinical photographs as well as by using immunohistochemical techniques in order to find the distribution and the amount of the extracellular matrix fibrillar components, i.e., collagen types I and III.Results: Low energy laser treatment caused a rapid wound healing without scar tissue formation (compared to the high energy laser group) and clinical signs of scar tissue formation (compared to control incisions with the conventional scalpel). During the study period, the laser‐induced lesions healed through reparative synthesis of the matrix proteins, which led to filling of the tissue defects. The regenerative processes were similar in the low‐energy laser group and in the control incisions. In the high‐energy lased tissues, we observed a delayed replacement of the defects by newly formed extracellular matrix proteins.Conclusions: This study showed a slower wound healing in the high‐energy lased tissues. A similar healing in the low‐energy lased tissues and in the incisions with the conventional scalpel was observed. The differences in the distribution of matrix proteins during healing and the coagulation of the tissues, which were exposed to low‐energy laser treatment, might be the explanation for the minimal scarring, contraction, and pigmentation of the lased tissues as compared to conventional incisions. © 1995 Wiley‐Liss, Inc.
Combination sensor for measurement of light and temperature
Authors: Welch A. J. , Cain C. P. 
Published: March 2007

AbstractThis report describes light and temperature measurements made in a gel cell using a single probe. Glass pipettes were drawn to an outer tip diameter of 50 μm and a thermocouple was vapor deposited at the tip of the pipette. Direct absorption of light by the thermocouple produced near step changes in temperature proportional to the fluence rate of the light. © 1995 Wiley‐Liss, Inc.
Lasers in ophthalmology
Authors: Krauss Joel M. , Puliafito Carmen A. 
Published: March 2007

AbstractThis article reviews the principle uses of ophthalmic lasers, providing historical background with an emphasis on new applications and areas of investigation. Ophthalmic photocoagulation was the first medical laser application and has restored or maintained vision in millions of people. More recently, photodisruption and, increasingly, ablation have gained prominence for treating a wide range of ocular pathology. The unique properties of lasers have also been harnessed for diagnostic purposes, with optical coherence tomography representing a significant improvement over existing imaging methods. Many ophthalmic applications of lasers have been developed, but the field is a dynamic one which continues to evolve along with laser technology itself. © 1995 Wiley‐Liss, Inc.
An anterolateral thigh flap based on the superior cutaneous perforator artery: An anatomic study and case reports
Authors: Chen Zhong , Zhang Chun , Lao Jie , Xing Jin‐Jun , Zhu Min‐Xing , Wu Yang , Ma An‐Jun 
Published: March 2007

AbstractThis study was performed to observe the patterns of the superior perforator artery as a pedicle for an anterolateral thigh flap and report the results of clinical application. The perforator arteries at the anterolateral part of the thigh were observed on 50 lower limbs from embalmed cadavers and the results of 65 clinical cases who received transfer of the anterolateral thigh flap, which adopted the superior perforator artery as the pedicle. This study found that 34 superior perforator arteries presented in 29 of the 50 cadaveric limbs (58%), which might arise from the ascending branch, the transverse branch, and the descending branch of the lateral circumflex femoral artery. All flaps of the 65 clinical cases survived postoperatively. Our results showed that the superior perforator artery has a high occurrence and a relative constant location. We thought that it could be adopted as a complement of the conventional perforator artery. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
The dependence of sustained bladder contractions provoked by filling or by subcutaneous bethanechol upon sacral afferent pathways
Authors: El‐Salmy S. , Downie J. W. , Awad S. A. 
Published: March 2007

AbstractThe dependence of the detrusor response to sc bethanechol chloride on afferent nerves was studied in 20 cats by selective dorsal rhizotomy L7‐S3 in different combinations. Combined S1 and S2 dorsal rhizotomy abolished both the micturition reflex and the sustained bladder contraction in response to sc bethanechol administration. However in six of 13 experiments selective S2 dorsal rhizotomy abolished the bethanechol response while leaving the mictu rition reflex intact, albeit with a higher threshold volume. On the other hand, the bethane chol response was always lost if the micturition reflex was lost. We conclude that the sustained bladder response to sc bethanechol requires a complete reflex pathway involving sacral dorsal roots.
Normative bladder diary measurements: Night versus day
Authors: Parsons Matthew , Tissot William , Cardozo Linda , Diokno Ananias , Amundsen Cindy L. , Coats Alfred C. ,   on behalf of the Bladder Diary Research Team
Published: March 2007

AbstractAimsTo investigate bladder diary measurements from asymptomatic subjects in separate night and day periods, including their relationships to age and total volume voided. A major objective of this study was to generate age‐adjusted reference values against which clinical measurements of nocturia can be compared.Materials and MethodsThree‐day bladder diaries were collected from 161 females and 92 males (age: median = 46.5 years; range = 19.6–84.6 years). We studied: average volume voided (“Vavg”), voiding frequency, and four urine production measures (volume, production rate, and their ratios to 24‐hr values)ResultsBoth day and night Vavg and frequency increase with increasing volume. The night increase is much steeper than the day increase. With aging, frequency increases, Vavg decreases, day production decreases and night production increases. These age effects are steeper for males than females. Adjusting for age by regression analysis reduces the night production measure's variability by about 40%, and expressing production rate as a percent of the 24‐hr value reduces the variability by an additional 20%.ConclusionsWe present regression equations that can be used to adjust night and day Vavg frequency and production rate reference values for the influences of age and total volume. Using these equations, we calculated a table of 95% confidence limits of night urine production and night frequency. The least variable night urine volume measurement studied was night/24‐hr production rate; hence this may prove to be the most efficacious measurement to use in detecting nocturnal polyuria. Neurourol. Urodynam. 26:465–473, 2007. © 2007 Wiley‐Liss, Inc.
Glutamate measurement in Parkinson's disease using MRS at 3 T field strength
Authors: Kickler Nils , Krack Paul , Fraix Valérie , Lebas Jean‐François , Lamalle Laurent , Durif Franck , Krainik Alexandre , Rémy Chantal , Segebarth Christoph , Pollak Pierre 
Published: March 2007

AbstractLoss of nigral dopamine neurons in Parkinson's disease induces abnormal activation of glutamate systems in the basal ganglia. The purpose of this study was to assess these changes in the lentiform nucleus using MRS with optimized glutamate sensitivity (TE‐averaged method). Ten patients with Parkinson's disease and 10 healthy controls were examined. Compared with healthy controls, no significant differences in glutamate were measured in patients, but a trend to lower total creatine was observed. Copyright © 2007 John Wiley & Sons, Ltd.
Discontinuous Galerkin finite element methods for dynamic linear solid viscoelasticity problems
Authors: Rivière Béatrice , Shaw Simon , Whiteman J.R. 
Published: March 2007

AbstractWe consider the usual linear elastodynamics equations augmented with evolution equations for viscoelastic internal stresses. A fully discrete approximation is defined, based on a spatially symmetric or non‐symmetric interior penalty discontinuous Galerkin finite element method, and a displacement‐velocity centred difference time discretisation. An a priori error estimate is given but only the main ideas in the proof of the error estimate are reported here due to the large number of (mostly technical) estimates that are required. The full details are referenced to a technical report. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
Combined finite difference and spectral methods for the numerical solution of hyperbolic equation with an integral condition
Authors: Ramezani Mehdi , Dehghan Mehdi , Razzaghi Mohsen 
Published: March 2007

AbstractIn this work the combined finite difference and spectral methods have been proposed for the numerical solution of the one‐dimensional wave equation with an integral condition. The time variable is approximated using a finite difference scheme. But the spectral method is employed for discretizing the space variable. The main idea behind this approach is that we can get high‐order results. The new method is used for two test problems and the numerical results are obtained to support our theoretical expectations. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007