bluuebunny/crossref_metadata_2025_split huggingface dataset:
Erb:YAG and Hol:YAG Laser Osteotomy: The Effect of Laser Ablation on Bone Healing
Authors: Buchelt Martin , Kutschera Hans‐Paul , Katterschafka Thomas , Kiss Harald , Lang Susanne , Beer Rudolf , Losert Udo 
Published: March 2007

AbstractSixty‐nine male Sprague Dawley rats were divided into three groups of 23 animals each and osteotomies were performed in group 1 with a power saw, in group 2 with the Erb:Yag laser, and in group 3 with the Hol:YAG laser. Two animals of each group were sacrificed 1 week, 4, 8, and 12 weeks after operation for histologic investigation, and five animals of each group at 4, 8, and 12 weeks after osteotomy for torque testing. Anterior‐posterior (AP) radiographs were taken at the same time points and investigated for callus formation and development of pseudoarthrosis. All tibiae osteotomied with the Ho1:YAG laser (group 3) developed pseudoarthrosis within 12 weeks and, therefore, torque testing could not be performed for this group. Biomechanical measurements of bone treated by power saw or Erb:YAG laser osteotomies, respectively, showed no significant statistical difference in the stability of bone between the two groups. Histologic examination after 1 week exhibited fibrous tissue at the site of osteotomy in rats of all three groups and additionally carbonization in rats of group 3. Saw osteotomies resulted in more callus formation than Erb:YAG osteotomies, but both techniques provoked a certain reunion within 8 weeks. Hol:YAG laser‐treated osteotomies, however, exhibited formation of dense fibrous tissue, carbonization and no callus formation within 12 weeks. Radiographic pictures showed more callus formation for saw osteotomies as compared to those performed with the Erb: YAG laser. For Hol:YAG laser osteotomies pseudoarthrosis was identified also radiologically. © 1994 WiIey‐Liss, Inc.
Laser patch welding: Experimental study for application to endoscopic closure of bronchopleural fistula, a preliminary report
Authors: Sensaki Koji , Arai Tsunenori , Tanaka Susumu 
Published: March 2007

AbstractBackground and Objective: Postoperative bronchopleural fistula is a serious complication following pulmonary resection. To close the bronchopleural fistula, we developed a new method of endoscopic patch welding using laser tissue welding between bronchial tissue and a patch.Study Design/Materials and Methods: The feasibility of the laser patch welding was examined by in vitro and in vivo animal experiments. A newly developed carbon monoxide (CO) laser and an Argon ion laser were evaluated. Various tissue membranes and artificial membranes were evaluated as patch materials.Results: We found that the combination of expanded polytetrafluoroethylene (e‐PTFE; 200 μm in thickness) and the CO laser with contact irradiation method offered the strongest laser patch welding. Using this combination, the irradiation at 400 W/cm2 for 10 seconds resulted in 16–18 g of measured traction strength at the welding spot (2 mm in diameter). The welded e‐PTFE patch at bronchial stump remained for 5 weeks.Conclusion: Our results encourage use of this novel laser patch technique for clinical applications. © 1995 Wiley‐Liss, Inc.
Is there a need for guidelines for OB/GYN residents to use the laser?
Authors: Olivar August C. , Simon Helene 
Published: March 2007

AbstractBackground and Objective: With the developing technologies and the extensive use of different wavelength lasers for treatment of some gynecologic conditions, many residencies in the United States face pressure to give credentialing to residents wishing to utilize the laser(s). The objective of this study was to assess the need for credentialing.Study Design/Materials and Methods: A survey was sent to all U.S. program directors of obstetrics and gynecology.Results: Of 281 surveys mailed, 138 responded (49.1%); 136 utilized some wavelength laser in the treatment of some gynecologic conditions. The most commonly used laser was the carbon dioxide (CO2), and the least used was the argon laser. Eighty‐four programs (61.8%) had a written policy; 54 (38.2%) did not. Postgraduate courses were necessary in 81 programs (59.6%), leading to some form of credentialing.Conclusions: The vast majority of programs (98.6%) utilized some wavelength laser as a therapeutic modality in gynecology, and 73.5% of the residency programs would like standardized guidelines for residents. © 1995 Wiley‐Liss, Inc.
Lasers in dentistry
Authors: Wigdor Harvey A. , Walsh Joseph T. , Featherstone John D. B. , Visuri Steven R. , Fried Daniel , Waldvogel Joseph L. 
Published: March 2007

AbstractSince the development of the ruby laser by Maiman in 1960, there has been great interest among dental practitioners, scientists, and patients to use this tool to make dental treatment more pleasant. Oral soft tissue uses are becoming more common in dental offices. The possible multiple uses of lasers in dentistry, beyond soft tissue surgery and dental composite curing, unfortunately, have not yet been realized clinically. These include replacement of the dental drill with a laser, laser dental decay prevention, and laser decay detection. The essential question is whether a laser can provide equal or improved treatment over conventional care. Safe use of lasers also must be the underlying goal of proposed or future laser therapy. With the availability and future development of different laser wavelengths and methods of pulsing, much interest is developing in this growing field. This article reviews the role of lasers in dentistry since the early 1960s, summarizes some research reports from the last few years, and proposes what the authors feel the future may hold for lasers in dentistry. © 1995 Wiley‐Liss, Inc.
High power Ho:YAG laser ablation of intervertebral discs: Effects on ablation rates and temperature profile
Authors: Buchelt Martin , Schlangmann Bodo , Schmolke Stephan , Siebert Werner 
Published: March 2007

AbstractBackground and Objective: As the Ho:YAG laser gained increasing importance in recent experimental and clinical investigations, this study was performed to investigate the effect of power on ablation rates and temperature during disc ablation with a high power Ho:Yag laser under simulated clinical conditions.Study Design/Materials and Methods: A high power Ho:YAG laser was used to investigate the influence of increasing power from 10 to 32 Watt on ablation rate (mg) and temperature (°C). Ablation weight was measured by a precision scale calculating the difference of the pre‐ and postlasing weight of the specimen after application of total energies of 1,000, 1,500, and 2,000 J. Temperatures were measured by thermoprobes, which were connected via a thermomodule to an amplifier and the signal was plotted by a computer with appropriate software.Results: Whereas ablation rate rose almost linearly with total energy, increasing power above 20 W did not essentially improve ablation rate. Temperatures reached their highest values after application of a total energy of 500 J and did not rise further, whereas increasing power did not induce a rise in temperature.Conclusions: Regarding the chosen experimental setting, maximum temperatures are reached after application of 500 J, and increasing power does not induce a rise in temperature. © 1995 Wiley‐Liss, Inc.
HeNe laser therapy by fibroendoscopy in the mucosa of the equine upper airway
Authors: Gomez‐Villamandos R. J. , Valenzuela J. M. Santisteban , Calatrava I. Ruiz , Gomez‐Villamandos J. C. , Jurado I. Avila 
Published: March 2007

AbstractBackground and Objective: A study was made of the effects of low‐level laser irradiation on the cicatrization of superficial wounds in the pharyngeal mucosa of the horse.Study Design/Materials and Methods: Duplicate pharyngeal mucosal ulcers were induced in 12 Spanish horses with submucosal injection of sulfuric acid. A fibroendoscope and an He‐Ne laser were used to treat one of the ulcers and the second ulcer in each animal was left untreated, serving as a control. Biopsy samples for the histological study were taken after the seventh laser therapy session from the two animals.Results: Irradiated lesions cicatrized at 10.5 days and nonirradiated lesions cicatrized at 18.0 days. Statistical analysis revealed highly significant differences (P < 0.0001) between the irradiated and control groups. Histological study of the control samples showed epithelial coagulation necrosis, edema, and microthrombi. However, in samples from the irradiated lesions no inflamatory edema, numerous active fibroblasts, connective tissue, and intensive epithelial regeneration were observed.Conclusion: Macroscopic and microscopic results indicated that laser treatment accelerated the cicatrization. Irradiated lesions cicatrized faster than control. These results suggest beneficial effects of low‐level laser irradiation therapy on equine pharyngeal ulcerative lesions. © 1995 Wiley‐Liss, Inc.
Laser‐induced release of liposome‐encapsulated dye to monitor tissue temperature: A preliminary in vivo study
Authors: Mordon S. , Desmettre T. , Devoisselle J. M. 
Published: March 2007

AbstractBackground and Objective: The objective of this in vivo study was to assess the possible use of temperature‐sensitive liposomes as a new approach to monitor the temperature induced by a laser.Study Design: An in vivo/ex vivo study was performed in rat liver after i.v. injection of liposomes loaded with a fluorescent dye.Materials and Methods: Temperature‐sensitive liposomes (DSPC: Di‐Stearoyl‐Phosphatidyl‐Choline) were loaded with carboxyfluorescein. These liposomes (1 ml solution) were injected into adult male Wistar rats. Two hours later, the liver was exposed and irradiated with a 100 W Nd:YAG laser using pulses lasting from 100 to 260 ms. Simultaneously, the surface temperature was recorded with a thermographic camera. The fluorescence emission was measured with a fluorescent imaging system.Results: The results showed that the dye was released in response to laser energy. The amount of the drug release increased linearly with increasing temperature in the range 42–60°C. Moreover, the release occurred in a short period of time upon brief exposure to its phase transition temperature.Conclusion: The feasibility of temperature monitoring by using laser‐induced release of liposome‐encapsulated dye was demonstrated. This procedure could conceivably prove useful for controlling the thermal coagulation of biological tissues such as blood vessels. © 1995 Wiley‐Liss, Inc.
Model study to investigate the contribution of spallation to pulsed laser ablation of tissue
Authors: Paltauf Günther , Schmidt‐Kloiber Heinz 
Published: March 2007

AbstractBackground and Objective: Absorption of a short laser pulse produces high thermoelastic stress in the irradiated volume. The relaxation of this stress at a free (tissue–air) surface leads to tensile loading, resulting in mechanical spallation. Using model substances, we investigated the role of this effect in tissue ablation.Study Design/Materials and Methods: Stained water and gelatine were irradiated with short pulses (8 ns duration) from a Nd:YAG laser at 1,064 nm wavelength. The dynamics of the induced effects were observed with laser‐flash photography and stress wave detection.Results: Spallation is indicated by the formation of cavitation bubbles below the irradiated surface and is strongly influenced by impurities serving as nucleation sites. Material ejection due to spallation was observed in the liquid sample at a fluence leading to a temperature below the boiling point but needed a temperature in excess of 100°C in gelatine, owing to the small mechanical energy available for this process, estimated to be <1%.Conclusion: The mechanical action of thermoelastic stress waves is characterized by high stress amplitudes but low energetic efficiency. A model combining spallation and vaporization is therefore proposed for efficient tissue ablation.
Clinical and preclinical photodynamic therapy
Authors: Fisher Anita M. R. , Murphree A. Linn , Gomer Charles J. 
Published: March 2007

AbstractPhotodynamic therapy (PDT) is a treatment modality that utilizes a photosensitizing drug activated by laser generated light, and is proving effective for oncologic and nononcologic applications. This report provides an overview of photosensitizers, photochemistry, photobiology, and the lasers involved in photodynamic therapy. Clinical and preclinical PDT studies involving Photofrin and various second generation photosensitizers are reviewed. © 1995 Wiley‐Liss, Inc.
Laser photocoagulation of prostate: Influence of dosimetry
Authors: Motamedi Massoud , Torres Jorge H. , Orihuela Eduardo , Pow‐Sang Mariela , Cowan Daniel F. , Warren Michael M. 
Published: March 2007

AbstractBackground and Objective: Recently, increasing enthusiasm has been shown for application of lasers for the treatment of benign prostate hyperplasia (BPH). However, little is known about the thermodynamics of prostatic tissue response during laser irradiation and how the treatment outcome can be optimized. Our objective was to conduct a systematic study of the influence of exposure parameters on the extent of tissue coagulation and to determine the effects of rate of tissue heating on lesion size by comparing the tissue response to high laser power rapid heating vs. low laser power slow heating.Study Design/Materials and Methods: Nd: YAG laser irradiation of prostate was performed in 15 mongrel canines, using an incident power of 15, 30, or 50 Watts (at the fiber tip) and an exposure time varying from 30 to 300 seconds. The laser beam was delivered via a Urolase side‐emitting catheter. The tissue response was compared based on gross as well as histological evaluations of thermal lesions.Results: The depth of coagulation necrosis increased as the laser power was reduced from 50 W to 30 W and further to 15 W while the total delivered energy was kept constant at 2,700 J by adjusting the exposure time. The difference between the three heating rates was more dramatic when the estimated volume of coagulated tissue was considered. Increasing the irradiation tune for the low power (15 W) from 180 to 300 seconds resulted in enlarging the coagulated volume by a factor of 1.6. However, for high power (50 W), increasing the exposure time from 54 to 90 seconds resulted in increasing the coagulated volume by a factor of 1.2. Conclusion: This study suggests that a slow heating regimen yields larger volumes of coagulation necrosis than the currently used rapid heating approach. © 1995 Wiley‐Liss, Inc.
Creation of a volume lesion in the dog prostate using neodymium: YAG laser coagulation: Concepts for clinical treatment
Authors: Perlmutter Aaron P. , Lopez Miguel , Vaughan E. Darracott 
Published: March 2007

AbstractBackground and Objective: The purpose of this study was to determine the geometrical development of a coagulated zone in the canine prostate during free beam side fire Nd: YAG laser coagulation.Study Design/Materials and Methods: A series of 10 male dogs underwent endoscopic prostatic Nd: YAG fixed position laser coagulation through a suprapubic cystotomy using a right‐angle deflecting delivery catheter (Microvasive, Boston, MA) at times varying from 10 to 120 seconds at 30 watts. In addition, two dogs underwent lasing by pulling the catheter at 1 mm/s in four quadrants. Acute gross and microscopic pathology specimens were prepared and the lesion shape and volume determined.Results: Analysis of the coagulated volume showed that during the initial 15 seconds of lasing, the zone of coagulation approximates a sphere centered on the urothelium opposite the laser fiber. However, as lasing progressed, the lesion changed from a sphere to an expanding ellipse. This changing geometry can be explained by the absorption and scatter characteristics of the laser and the temperature equilibrium that is established within the prostate.Conclusion: An understanding of this time‐dependent geometrical shift from a sphere to an ellipse allows the surgeon to supplement the fixed protocols for lasing at certain positions for given amounts of time. Specific plans can then be established for tissue at the bladder neck, apex, anterior stroma, floor, and irregular prostatic regrowth. © 1995 Wiley‐Liss, Inc.
Double‐blind, placebo‐controlled investigation of the effect of combined phototherapy/low intensity laser therapy upon experimental ischaemic pain in humans
Authors: Mokhtar Basim , Baxter G. David , Walsh Deirdre M. , Bell A. Jean , Allen James M. 
Published: March 2007

AbstractBackground and Objective: This study assessed the putative analgesic effect of combined monochromatic light/laser irradiation at low intensity (660–950 nm; 31.9 J/cm2; pulsed at 16 or 73 Hz). Study Design/Materials and Methods: The investigation was completed under double‐blind conditions using a standardised form of the submaximal effort tourniquet technique. Healthy male volunteers naive to the experimental conditions (n = 45) attended on two occasions for the purposes of pain induction, the first during which baseline data were obtained and on a second occasion during which they were randomly allocated to one of two treatments or a placebo condition. For the treatment conditions, irradiation was applied to the ipsilateral Erb's point at the parameters stated; for the placebo condition, sham “irradiation” was delivered using a dummy unit. Pain was measured using computerised visual analogue scales and McGill Pain Questionnaires (MPQ) to assess “current pain intensity” and “worst pain experienced,” respectively.Results: Analysis of variance and appropriate post hoc tests demonstrated only a weak (but significant) hypoalgesic effect compared to placebo (P<0.05) in the treatment group irradiated at 16Hz for the sensory component of the MPQ; other comparisons were found to be nonsignificant.Conclusions: These results do not provide convincing evidence for the hypoalgesic potential of combined monochromatic light/laser irradiation, at least at the parameters used here, and thus indicate the necessity of additional work to investigate this modality further in order to assess the potential benefit, if any, of such treatment in the clinical setting. © 1995 Wiley‐Liss, Inc.
Laser‐assisted removal of a foreign body in the bronchial system of an infant
Authors: Boelcskei Pal L. , Wagner Manfred , Lessnau Klaus‐Dieter K. L. 
Published: March 2007

AbstractBackground and Objective: Foreign body aspiration is an important cause of acute respiratory distress in children. Removal by use of rigid tracheo‐bronchoscopy under general anesthesia is usually the treatment of choice, but this technique is sometimes unsuccessful. Thoracotomy in these instances often cannot be avoided.Study Design/Patients and Methods: Case report with review of the literature. The patient was 19 months old with an aspirated foreign body. A Neodym:YAG laser with a special small‐size delivery system was inserted into the rigid “baby” bronchoscope. The NeodymiumrYAG laser with a wavelength of 1,064 nm and a Helium‐Neon 630 nm light guide provided an aiming beam to weaken and cut the aspirated chicken bone.Results: The foreign body could be easily removed with a regular biopsy forceps.Conclusion: We discuss a patient in whom laser‐assisted rigid tracheobronchoscopy obviated the need for thoracotomy. © 1995 Wiley‐Liss, Inc.
Sodium flux and bioenergetics in the ischemic rat liver
Authors: Blum Haywood , Osbakken Mary D. , Johnson Robert G. 
Published: March 2007

AbstractConcurrent 23Na and 31P nuclear magnetic resonance spectroscopy has been employed to study the effects of ischemia upon the high‐energy phosphagens and sodium ion concentration within the in vivo rat liver. High‐energy phosphates in the form of ATP were depleted within 10 min of the onset of ischemia when measured by NMR. However, similar liver samples subjected to analytical biochemistry retained 27 ± 12% of their ATP after a similar 10‐min ischemic insult. Time‐dependent 23Na NMR measurements, obtained in the presence of the shift reagent Dy(TTHA) to distinguish intracellular from extracellular sodium, revealed a rapid rise in the intracellular sodium when the liver was made ischemic. Intracellular and extracellular sodium concentrations approached equilibrium with an exponential time constant of 14.7 ± 7 min. The initial rate of sodium influx was calculated to be 1.50 meq · 1−1 · min−1. The results indicate that the ischemic liver has a high passive sodium permeability and that NMR detectable 31P signals reflect the actual availability of cytosolic high‐energy phosphates to enzymes, in this instance the membrane‐bound [Na+, K +]‐ATPase. © 1991 Academic Press. Inc.
Continuous overnight monitoring of bladder activity in vesicoureteral reflux patients: II. Bladder activity types
Authors: Nielsen J. Bugge , Nøsbrgaard J. P. , Schwartz SøSrensen S. , Munch JøSbrgensen T. , Djurhuus J. C. 
Published: March 2007

AbstractContinuous overnight monitoring of the bladder activity was undertaken in children with vesicoureteral reflux. The investigation succeeded in 46 of 56 patients and showed bladder activity in all cases. Three types of bladder activity were revealed. One consisting of single contraction episodes exhibited periodicity with intervals of approximately 90 min. The second type consisted of a complex of contractions with increasing amplitude. They frequently lead to voiding. This type of activity seemed to be related to the bladder fullness. The third type of bladder activity consisted of vigorous repetitive contractions, most frequently found in the nonenuretic part of the material. The contractions in type III most frequently occurred with a frequency of 3–6/min.The degree of reflux was related to the type of bladder activity. Thus, the degree of reflex was significantly increased in patients with the second and third type of bladder activity when compared to patients with type I. The study shows that bladder activity takes place outside provocational episodes, e.g., cystometry and micturition, and seems to be closely related to the severity of reflux.
Bladder diary patterns in detrusor overactivity and urodynamic stress incontinence
Authors: Parsons Matthew , Amundsen Cindy L. , Cardozo Linda , Vella Maria , Webster George D. , Coats Alfred C. 
Published: March 2007

AbstractAimsOur aims were: (1) to describe and compare frequency‐volume and incontinence episode patterns in patients with urodynamic stress incontinence (USI) and detrusor overactivity (DO) as measured by a hand‐written and computer‐analyzed bladder diary and (2) to compare degree of separation between these clinical groups produced by raw diary measurements and after age‐ and total‐volume‐adjustment against a reference population.Materials and MethodsWe studied 58 patients with USI, 29 with DO, and 22 with both USI and DO. From 3‐day hand‐written and computer‐analyzed bladder diaries, we calculated average and maximum volume voided (Vol/Void), voiding frequency and volume voided over 24 hr, and number, size and type (whether accompanied by activity or urge) of incontinence episodes.ResultsCompared to the USI patients, the DO patients tended to have (1) higher voiding frequency, (2) lower Vol/Void, (3) more urge‐related, than activity‐related leaks, (4) smaller volume, and equally frequent leaks and (5) more severe incontinence symptoms. The age‐ and volume‐adjusted percentiles better separated the USI and DO groups' frequency and volume measurements than did the raw measurements. Unexpectedly high percentages of our USI patients had low Vol/Void measurements, high voiding frequency, and predominantly urge‐related leaks. A subgroup of 29 USI patients with “low” (average volume <30th reference population percentile) Vol/Void measurements had high incidences of urgency and urge‐related leaks.ConclusionsReference population percentiles better separate the frequency/volume patterns of USI and DO than do the raw measurements. We found a subgroup of USI patients that had an OAB‐like clinical picture. Neurourol. Urodynam. 26:800–806, 2007. © 2007 Wiley‐Liss, Inc.