bluuebunny/crossref_metadata_2025_split huggingface dataset:
The use of the CO2 laser in otolaryngology: Ten years of experience
Authors: Andrews Albert H. 
Published: March 2007

AbstractAccessory instruments have been developed consisting of retractors, the axial adapter, the slip‐on adapter for the laryngoscope and the lynch suspension apparatus, the upper‐hand abdominal retractor modified, and chain for neurological sponges, and mirrors. The initial bronchoscopic coupler was used until a manufactured one was obtained from Cavitron. In addition to the cases shown in the table, the laser has been used in conjunction with the Department of Ophthalmology, the Department of Orthopedic Surgery, and the Department of Gynecology. The advantages to laser surgery are stated.
Ultrastructural findings after the use of a CO2 laser in carpal tunnel surgery
Authors: Strohecker J. , Piotrowski W. , Lametschwandtner A. 
Published: March 2007

AbstractThe laser beam enables tissue cutting and care of the cut edges, which prevents an increased scar tissue formation. For this reason we have used the laser beam in carpal tunnel surgery for transection or sealing of the transverse carpal ligament since 1981 because scar tissue formation is for the most part the cause of recurrence. Scanning‐electron microscopic studies of the carpal ligament show the difference between the laser and traditional cutting techniques. After using the laser beam, there is no normal tissue structure; the cut surface appears as uneven and rough in contrast to the cut surface of the cold knife.
Continuous wave (CW) and pulsed laser effects on vascular tissues and occlusive disease in vitro
Authors: Davi S. K. 
Published: March 2007

AbstractHuman arterial segments with occlusive defects and acute dog hearts were exposed, in vitro, to high‐energy pulsed and continuous wave (CW) laser beams at argon (514 nm) and Nd‐YAG (1,064 nm) wavelengths, using various pulse powers, durations and pulse repetition rates. The laser effects included vaporization of plaques in the arterial segments and penetration of the pericardial sac, evaporation of pericardial fluid, and discoloration of tissue with crater‐like lesions in the impact zone, all as a result of vaporization of heart muscle tissues. The areas affected and depth of penetration depended on the wavelength, power, pulse duration, and mode of energy deposition. Focused nanosecond Nd‐YAG laser pulses at repetition rates of 40‐50 Hz caused ablation or vaporization of hard plaques and kidney stones in air and saline. Picosecond (mode‐locked) argon laser pulses at repetition rates of 3.8 MHz–average power 6.5 W, peak power of 230 W–caused effective vaporization of hard plaques and kidney stones in air and saline. Picosecond argon laser pulses–average power 1 W, peak power 250 W– were not effective in vaporization. Transmission characteristics of the various types of laser pulses through fiber optic waveguides were determined. The energy and power density required to vaporize fatty and hard plaques and kidney stones were tabulated as a function of laser wavelength, pulse energy, duration, and repetition rates.
The comparative effects of the Argon, Nd:YAG, and Argon‐pumped Dye lasers on human platelets and erythrocytes in vitro
Authors: Doerger Phyllis T. , Glueck Helen I. , Bel‐Kahn J. van der , Taylor Allen , Goldman Leon 
Published: March 2007

AbstractThe effects of three lasers, Argon, Nd:YAG, and Argon‐pumped Dye, on three types of platelet preparations were evaluated. Either EDTA or buffered citrate served as anticoagulants. Platelets separated from plasma and suspended in buffer showed no decrease in counts following lasering, but morphologic damage was evident with transmission electron microscopy (TEM). In platelet‐rich plasma, a fall in counts was noted for the Argon and the YAG (at high energy only) but was absent when the Dye laser was employed. Morphologic damage (TEM), however, was noted with all three lasers. When whole blood preparations were used, more marked changes in both RBCs and platelets were seen in samples collected in EDTA compared with citrated samples. Morphologic damage (TEM) to platelets and RBCs occurred with all three lasers. An artifactual increase in “platelet counts,” the appearance of spherocytes, and an increase in plasma Hb indicated RBC injury. Both platelets and erythrocytes were sensitive to variations in power (wattage) despite constant total energy delivery.
Thermal and optical properties of living tissue: Application to laser‐induced hyperthermia
Authors: Svaasand Lars O. , Boerslid Tone , Oeveraasen Marit 
Published: March 2007

AbstractThis report discusses the thermal distribution in living tissue during hyperthermic treatment with visible or infrared electromagnetic irradiation. The underlying physical mechanisms that determine the transient as well as the steady‐state temperature distribution are discussed. Results from the treatment of a murine tumor model, C3H/Tif mammary adenocarcinoma in C3D2F1/Bom mouse strain, are reported. Total cure, defined by a nonrecurrent tumor, was obtained in 30% of the cases.
Effects of argon, dye, and Nd: YAG lasers on epidermis, dermis, and venous vessels
Authors: Landthaler M. , Brunner R. , Braun‐Falco O. , Haina D. , Waidelich W. 
Published: March 2007

AbstractThe aim of the present study, which was performed at the dorsal aspects of the ears of guinea pigs, was to compare effects of different lasers on epidermis, dermis, and small venous vessels. Irradiations were performed with argon, dye, and Nd:YAG lasers.In the first series tissue repair processes were studied after argon laser application. Laser defects were excised after 1, 4, 8, and 14 days and were prepared for routine histological examination. The breadth of epidermal defect and extent of dermal coagulation and occlusion of vessels by thrombus formation were examined histologically. In a second series parameters of irradiation (ie, exposure time, laser power) of the three different lasers were changed systematically. Laser‐induced morphological tissue changes could be best observed 24 hours after irradiation. Each of the lasers led to occlusion of vessels by thrombus formation and also coagulated epidermis and dermis. The extent of dermal and epidermal coagulation was less pronounced after dye laser application. Using short exposure times it was possible to reduce the extent of epidermal damage caused by argon and Nd:YAG lasers. Only 50‐msec dye laser pulses led to intravascular thrombus formation without epidermal and dermal damage.
Effects of Nd: YAG laser photoradiation on intra‐abdominal tissues: A histological study of tissue damage versus power density applied
Authors: Brackett Kim A. , Sankar M. Y. , Joffe Stephen N. 
Published: March 2007

AbstractLiver, spleen, and pancreas were subjected to laser photoradiation of 50– to 100‐Watt power levels. Samples were evaluated by light microscopy at 0 hours and 7, 14, and 21 days. Four zones of cellular damage were visible in liver and pancreas: coagulum, cavitation, acidophilia, and transition. Only the first three zones were clearly visible in the spleen. Mean lateral tissue penetration was 3.1 mm in liver, 3.3 mm in spleen, and 1.0 mm in pancreas. No significant increase in lateral penetration occurred with increasing power. Normal healing was observed in liver and spleen. Pancreatitis was found in all samples at 7 days postoperatively. At power levels of 80 W or less, recovery was observed. Above 80 W, pancreatic pseudocysts and necrosis led to death of the animals.
Biological effects of laser welding on vascular healing
Authors: White Rodney A. , Patrick Abergel R. , Lyons Richard , Klein Stanley R. , Kopchok George , Dwyer Richard M. , Uitto Jouni 
Published: March 2007

AbstractThe feasibility of welding thin‐walled microvessels by laser has been established. This report summarizes our experience using laser welding to repair thick‐walled, high‐pressure, 4 to 8‐mm canine arteries using CO2, Nd:YAG, and argon lasers. The CO2 laser did not produce seals that could withstand arterial pressure. Nd:YAG laser welds were initially successful, but the majority failed within 20 to 40 minutes. The argon laser uniformly sealed 2‐cm‐length arteriotomies that healed rapidly within 4 to 6 weeks and had less foreign body response compared to sutured controls. Laser welding may represent an alternative for repair of small‐and large‐diameter vessels with several advantages compared to conventional suture techniques.
CO2laser in brain stem gliomas
Authors: Mattos Pimenta L. H. , Mattos Pimentar T. M. , Mattos Pimenta A. 
Published: March 2007

AbstractThe author presents his experience with the use of carbon dioxide laser surgery on five patients with brain stem gliomas. Such problematically located tumors, when removed by this freehand, secure, and efficient technique, were completely evaporated with minimum trauma to neighboring tissue. This method represents new hope for these unfortunate patients. Additional time is needed before we can draw the conclusions regarding long‐term results of the treatment described.
Light dosimetry in brain tissue: An in vivo model applicable to photodynamic therapy
Authors: Powers Stephen K. , Tony Brown J. 
Published: March 2007

AbstractThe intensity of blue‐green (488 nm) and red (633 nm) light as a function of increasing distance from an implanted laser fiberoptic source in the brains of anesthetized rats was measured. There was significant (90%) attenuation of the light intensity for both 488 nm and 633 nm at a distance of 2.5 mm from the intracerebral laser light‐emitting source. At greater distances from the light‐emitting source that corresponded to areas in the cerebral cortex, there was greater attenuation of light intensity for increasing distance with 488 nm than with 633 nm because of the increased vascularity of the cortical mantle and absorption of 488 nm by hemoglobin. When hematoporphyrin derivative was given intravascularly, there was increased attenuation of 633 nm through the cerebral cortex that was similar to that seen for 488 nm in normals. Direct assessment of light intensity in living tissue, which we have shown is possible in this report, will aid in our understanding and interpretation of the histological changes that occur following photodynamic therapy.
Photodynamic therapy of endobronchial tumors
Authors: Mccaughan James S. , Williams Thomas E. , Bethel Bradley H. 
Published: March 2007

AbstractAfter presensitization with IV hematoporphyrin derivative (HpD), neoplasms in the tracheobronchial tree of 18 patients were treated by photodynamic therapy (PDT) with 630‐nm light from a tunable dye argon laser system delivered through quartz fibers passed through the biopsy channel of a flexible bronchoscope under local anesthesia. Tumor effect was measured by complete response (CR)—no visible tumor in area treated, partial response (PR)—tumor size or degree of obstruction reduced by more than 50% and some response (SR)—tumor or degree of obstruction reduced by more than 20% but less than 50%. One month or less after 30 treatments to 26 areas in 18 patients, there was 40% CR, 57% PR, and 3% SR. All tumors showed at least some response.Since many of these patients had end‐stage disease, the effect on the clinical condition and symptoms were evaluated using the Karnofsky Performance Status (KPS), oxygen requirements, and the presence or absence of respiratory symptoms. One month after treatment, 61% were clinically improved, with an increase of the average KPS from 48 to 61.Three patients with stage III primary lung cancer improved from being severely disabled requiring hospitalization to normal activity with effort and lived an average of 3.5 months.One patient with metastatic colon cancer was palliated from bedrest with continuous oxygen to normal activity with no oxygen for 12 months. A patient with hemoptysis and carcinoma in situ remains biopsy‐ and symptom‐free for 34 months.A patient with hemoptysis and cough from breast cancer metastases maintained CR, biopsy‐ and symptom‐free for 7 months.A patient with hemoptysis from recurrence at the bronchial stump maintained CR, biopsy‐ and symptom‐free for 13 months.Six patients with Stage III primary lung cancer with average KPS of 27 (severe) died in the hospital and lived an average of 5 weeks (two CR, two PR, two SR).One patient with atelectasis of the right lower lobe re‐expanded 14 days after treatments began.
Endoscopic papillotomy with Nd: YAG laser: An alternative to electrocautery
Authors: Sander Rainer , Poesl Hans 
Published: March 2007

AbstractWith the presentation of two cases of successfully performed endoscopic papillotomies, a new indication for Nd YAG laser treatment in gastroenterology is introduced.To the extent it thus far has been used, photocoagulation is a complementary alternative method if the usual papillotomy cannot be placed in the right cutting position.
CO2 laser in cancer surgery of the breast: A comparative clinical study
Authors: Ansanelli Vincent W. 
Published: March 2007

AbstractReview of the literature reveals little to no data regarding the use of the CO2 laser as a surgical modality in the local treatment of breast cancer. This study was undertaken to determine if the CO2 laser is a surgical improvement over the scalpel, influencing patient care during the surgical and postsurgical period. In the author's series, a total of 209 procedures were performed. Within this group, 105 cases were performed with CO2 laser and 104 cases performed with the scalpel. Biopsies were always performed as a separate procedure prior to definitive surgery. This study was not designed to compare cure rates, the medical follow‐up period being 1 year. The results of this study demonstrate a significant improvement in patients' postoperative care, surgical technique, and hospital cost‐effectiveness.
Far‐ultraviolet laser ablation of the cornea: Photoacoustic studies
Authors: Srinivasan R. , Dyer Peter E. , Braren Bodil 
Published: March 2007

AbstractWide bandwidth piezoelectric transducers made of thin (9 m̈m) polyvinylidene fluoride film have been used to make time‐resolved measurements of the stress‐wave generated by far‐ultraviolet (193 nm) laser ablation in corneal tissue in vitro. At high fluence (∼ 250 mJ/cm2), ablation commences within 10 ns (± 5 ns) of the laser pulse and generates short acoustic impulses (∼ 30 ns). The time profile of the ablation, when coupled to the energy requirements for ablation from earlier work, allows the estimation of a temperature and a half‐life for the thermal decomposition of the collagen in cornea. These values do not support a photo‐thermal mechanism for the ablation under the experimental conditions.
A histologic study of laser‐induced transmyocardial channels
Authors: James Frederick W. , Kaplan Samuel , Hardy Roger Ian , Goldman Leon , Bove Kevin E. 
Published: March 2007

AbstractCarbon dioxide lasers are reported to provide ischemic myocardium direct access to blood within the ventricular cavity by inducing transmyocardial channels which maintain patency in long‐term experiments. We have histologically examined the natural history of channels produced with this technique and compared them with transmyocardial channels created by needle puncture. Immediately after application of the laser, four concentric zones vaporization, carbonization, fixation, and transition could be distinguished along the transmyocardial path. Needle puncture channels were fully occluded within 48 hr, whereas laser‐induced channels maintained partial patency for a 2‐week period, after which they also became occluded. It appears likely that the instantaneous vaporization produced by the laser may delay the release of factors which mediate the healing process, but occlusion of channels was universal in this study. It remains to be determined whether or not variables such as wattage, beam diameter, or tissue temperature influence long‐term channel patency.
The use of the carbon dioxide laser permits primary closure of contaminated and purulent lesions and wounds
Authors: Raymond Hinshaw J. , Raul Herrera H. , Lanzafame Raymond J. , Pennino Ralph P. 
Published: March 2007

AbstractExcision of contaminated and purulent wounds with the carbon dioxide laser makes it safe to close the wounds primarily when certain steps are observed during the operation. The contaminated surface is sterilized with the defocused beam. The surgeons' and assistants' hands should not touch the contaminated areas, and both should wear two pairs of rubber gloves to protect against accidental contamination. All infected tissue is excised completely, and the wound cleansed by copious irrigation and the defocused laser. The wound may then be safely closed by simple sutures, skin graft, or by the rotation of a vascularized musculocutaneous flap. A series of cases are presented in order to illustrate these points.
Preliminary clinical studies with PDT by topical TPPS administration in neoplastic skin lesions
Authors: Sacchini V. , Melloni E. , Marchesini R. , Luini A. , Bandieramonte G. , Spinelli P. , Cascinelli N. 
Published: March 2007

AbstractCutaneous photosensitization by topical administration of a porphyrin derivative has been previously reported from experimental studies. Preliminary clinical trials performed at the National Cancer Institute of Milan in the last six months have confirmed the feasibility of treating skin lesions by topical application of photosensitizers. Fourteen cases of basal cell carcinoma were treated by local administration of tetraphenylporphinesulphonate (TPPS), vehicled by azone. Later, the tumor was exposed to a wavelength of 630 nm from a dye laser.We noted complete remission, as documented by biopsies, in all tumors, with clinical thickness less than 2 mm, whereas partial remission was obtained in tumors with clinical thickness more than 2 mm. Our experience suggests the possibility of a routine treatment by this method for flat basal cell carcinoma and pre‐malignant lesions, with remarkable advantages to conventional therapies. Our results have to be confirmed by increasing the number of cases and length of follow up; our short follow up does not allow us to make definitive claims regarding this therapy.
Bone fracture consolidates faster with low‐power laser
Authors: Trelles M. A. , Mayayo E. 
Published: March 2007

AbstractLow‐power laser radiation is currently used in the treatment of pain and osteoarticular inflammation. However, the mechanisms of the laser biostimulating effects on tissue are still not completely understood. With laser treatment, we have achieved activation of osseous regeneration in human bone fractures. After 7 years of positive clinical control in human beings, we decided to start an experimental study of fractures in the tibia of mice, histologically controlling its reparation after exposure to 632 nm. He/Ne laser in doses of 2.4 Joules in one point was used. The radiation was directly applied to the area of fracture in a series of 12 treatments (one treatment every second day). By optic microscope we observed, in the treated animals, an important increase in vascularization and faster formation of osseous tissue with a dense trabecular net compared to the control group, which presented only chondroid tissue and poor vascularization corresponding to an earlier stage of bone consolidation (controls were also analyzed by electron microscopy). Potentially, the laser effect might modulate the function of osteocytes, promoting faster metabolism and reaction of bone callus.
Head and neck applications of the milliwatt laser
Authors: Fried Marvin P. , Vernick David M. , Breslin Kathryn Ann , Moll Erik R. S. 
Published: March 2007

AbstractThe head and neck surgeon often uses the carbon dioxide laser. With the advent of new instrumentation, the frequency of usage will increase. The CO2 miliwatt laser offers the adventages of tissue welding, as well as cutting and ablation by virtue of the small spot size produced combined with low power output. Potential applications include microvascular and microneural anastomoses. The milliwatt laser can be used endoscopically for tissue resection with a high degree of precision with power densities comparable to current CO2 lasers. Moreover, the milliwatt laser can be applied to otology for cutting and welding of the tympanic membrane, tissue removal, and stapedotomy.
Quantitative and ultrastructural studies of excimer laser ablation of the cornea at 193 and 248 nanometers
Authors: Puliafito Carmen A. , Wong Kai , Steinert Roger F. 
Published: March 2007

AbstractExcimer laser radiation at 193 nm and 248 nm was used to create linear etch perforations of enucleated calf corneas. The etch depth per pulse was determined for various exposures, and specimens were examined by light and transmission electron microscopy. Compared to 248 nm, excimer laser ablation at 193 nm was found to have a lower threshold for onset of ablation, less increase in etch depth per pulse at increasing fluences, and less structural alteration in adjacent cornea. For 193 nm, structural alterations were minimal, confined to an area less than 0.3 μm wide, and did not increase with increasing fluence. These studies suggest that clinical strategies for excimer laser refractive surgery will employ the 193‐nm wavelength, with fluence chosen depending on surgical strategy. Ablation exposures above 600 mJ/cm2 at 193 nm may give the most repeatable etch depth.
Simple and sensitive CO2 laser visual screen
Authors: Huang Yao‐Xiong 
Published: March 2007

AbstractThe present paper describes a simple and sensitive CO2 laser visual screen which is made from silica gel with cobalt chloride as indicator. The screen can directly and almost immediately display a clear mode pattern of an exposing CO2 laser beam, it can respond to laser intensities ranging from 80 mW/cm2 to 26 W/cm2. It is suitable for the observation of both high‐power lasers, which are used for surgery, and very low power ones, which are used for biostimulation.
Spectroscopic, morphologic, and cytotoxic studies on major fractions of hematoporphyrin derivative and Photofrin II
Authors: Sun Chung‐Ho , Duzman Eran , Mellott John , Liaw L.‐H. , Berns Michael W. 
Published: March 2007

AbstractThis study characterizes the special properties of hematoporphyrin derivative (HpD) (Photofrin I) and Photofrin II with respect to the absorption and fluorescence spectra of the subfractions of the compounds in both solution and cells. In addition, data are presented demonstrating variation in the spectral amplitudes with respect to the age (shelf‐life) of the commercially available compounds. Data are also presented confirming that fraction III is the active ingredient‐containing fraction with respect to photosensitivity. The morphologic and electron microscopic analyses demonstrate that the first visible effect on cells following porphyrin sensitization can be detected within 1 minute of low level light exposure (10 J/cm2, 630 nm). The initial sites of morphologic damage are the mitochondria.
Experimental study of CO2‐laser‐induced histological effects on human fallopian tube: Determination of CO2 laser parameters to be used in microsurgery
Authors: Foulot Hervé , Lefebvre Gilles , Jagueux Michel , Darbois Yves 
Published: March 2007

AbstractThis experiment investigates CO2‐laser‐induced histological effects on fallopian tubes obtained during hysterectomies in women. Tubal transversal sections were performed at isthmic and ampullar sites. Forty strips were available for histological study of the cut section area. The role of different parameters such as radiation power and beam fractionation (continuous versus pulsed) on tissue lesions was assessed. In tubal microsurgery, the CO2 laser can be used as a scalpel with the predominant advantage of minimal tissular alterations. As a result of this study, our recommended parameters are the following: radiation power, 7–10 W; beam focalization zone, 0.2 mm; energy density, 20,000–35,000 W/cm2; continuous operation; moving speed, 1 cm/s.