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1.
Laser is the acronym for light amplification by stimulated emission of radiation; the first laser beam was generated in 1960 and initially used for medical application in 1963. Today's modern surgical laser units produce an intensely focused light beam of uniform wavelength that interacts with a variety of biological cell types to vaporize, cut, coagulate, or shrink tissues. The resulting effect depends on the optical properties of the tissue and the wavelength, power output, spot size, and duration of laser beam application. Different lasers are suited to specific surgical tasks relative to their beam wavelength, power output, mode of operation (continuous, pulsed or superpulsed), and application (contact or noncontact) and instrumentation. The documented advantages of laser surgery over conventional surgical procedures are improved hemostasis, the ability to ablate or vaporize tissue, endoscopic access to body cavities, improved postoperative comfort, and shorter hospitalization and recovery times. By the mid-1980s, laser use in equine surgery was reported; the carbon dioxide and neodymium:yttrium-aluminum-garnet were the first models integrated into practice. The primary application of laser technology in equine surgery was for the correction of various upper-respiratory tract abnormalities and still remains the most prevalent use through endoscopy. Today, surgical lasers are used for the treatment of problems in the urinary, reproductive, and musculoskeletal systems, in addition to the skin and the eye. When we combine advances in laser technology and the practice of equine surgery, the result is clinicians better equipped to treat and manage the more difficult cases.  相似文献   

2.
The clinical use of the carbon dioxide (CO2) laser and diode laser is increasing in veterinary medicine. New applications for their use are being explored, including ophthalmic applications. The use of lasers for small-animal corneal disease is fairly limited due to several factors. The ideal laser for corneal use is the excimer laser due to its extremely precise photoablative capability. However, the excimer laser is unlikely ever to become practical for veterinary use. The frequency of corneal disease in small animals in which tissue ablation is indicated is relatively low. And for most of these diseases, routine surgical techniques work as well or better than laser ablation. The CO2 laser can be used on corneal tissue, but must be used very cautiously so as not to ablate too deeply, creating serious scarring or perforation. There are also concerns regarding its effect on corneal nerves, stromal collagen, and corneal endothelium. The CO2 laser can be very effective in ablating limbal tumors with corneal extension. The use of the laser is less invasive, technically less difficult, and faster because of excellent hemostasis. The diode laser, due to its high melanin absorption, can be used effectively to ablate epibulbar melanomas with corneal stromal invasion.  相似文献   

3.
Two functionally important differences exist between the diode laser and the carbon dioxide (CO2) laser (used more commonly in small animal surgery). Diode laser energy is delivered through a quartz fiber instead of being reflected through an articulated arm or waveguide. Quartz fibers are generally more flexible and resilient than waveguides and can be inserted through an endoscope for minimally invasive procedures. Laser-tissue interaction is the other significant difference. The CO2 laser is completely absorbed by water, which limits the effect to visible tissue. The diode wavelength is minimally absorbed by water and may affect tissue as deep as 10 mm below the surface in the free-beam mode. With proper respect for the tissue effect, these differences can be used to the advantage of the patient.  相似文献   

4.
There are clearly a number of applications for which flexible endoscopic laser surgery has become the state of the art in equine surgery, and the Nd:YAG laser seems to be the most versatile instrument for this type of surgery. Nevertheless, it is critical to understand the advantages and disadvantages of each laser technique. For example, the Nd:YAG laser used in a noncontact fashion seems to be superior when ablation of tissue is required such as treatment of upper airway masses. Conversely, contact Nd:YAG laser techniques have proven themselves to be superior when more precise cutting is advantageous such as treatment of epiglottic entrapment. Ultimately, it seems that a range of lasers is necessary to ensure selection of the most appropriate technique, adding significantly to the expense of equipment but improving the outcome for a range of equine diseases.  相似文献   

5.
A neodymium:yttrium aluminum garnet (Nd:YAG) laser was used to study effects of applying laser irradiation transendoscopically to the corniculate process of the arytenoid cartilage in horses. Dosimetry was established initially in vitro in 10 corniculate cartilages that were irradiated and examined histologically to determine penetration depths at selected power settings. Eleven horses were given xylazine IV and butorphoral tartrate IV, and their left ventricle and corniculate process were irradiated. Six horses had left laryngeal hemiplegia and were euthanatized and necropsied 14 weeks after laser application and evaluation for upper airway stridor. Endoscopy was performed in the 5 other horses; they were euthanatized and necropsied at selected intervals to characterize the healing process. Healing was by second intention and was complete at 14 weeks. Two horses developed buds of granulation tissue along the laser incision, which resolved after a second laser application. Scar tissue formation resulted in left of midline displacement of the dorsal portion of the right corniculate process. The left ventricle healed without complications and was totally ablated. All horses had inspiratory stridor when exercised 14 weeks after laser irradiation.  相似文献   

6.
Laser in dermatology   总被引:1,自引:0,他引:1  
The laser is a tool that will augment the surgical techniques available to the veterinarian. When using the laser compared with traditional surgery there are multiple procedures that can be performed with much greater ease, and some procedures that previously could not be performed. Specialty and academic practices have used lasers for photodynamic therapy, lithotripsy of urinary calculi, and percutaneous disk ablation. This article will focus on the lasers use in dermatology. It is essential that the surgeon learn the basics of laser physics, how the laser interacts with tissue and the safety issues one needs to consider during its use. On deciding to use the laser the surgical techniques chosen should always be based on considering the advantages and disadvantages the laser has to offer. The use of biomedical lasers is a "cutting edge" technique now available to our veterinary field.  相似文献   

7.
Transendoscopic thermal preparation techniques like laser- or electrosurgery have proved to be most reliable for minimal invasive intrauterine surgery during operative hysteroscopy in mares. To determine the effect of Nd:YAG laser surgery on the endometrium and the complete uterine wall compared with electrosurgery, standard lesions were obtained by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and Nd:YAG laser surgery (contact, bare fibre, 25 Watt, exposure time four seconds, non contact, 80 Watt, exposure time four seconds) in five healthy mares on days d 0, 7, 14, 18 and 21. The gross effects were controlled endoscopically before the consecutive lesions were set. Following the last diathermic endometrial irritation, hysterectomy was performed under general anaesthesia. Recovery of the mares was uneventful. Specimens from the lesions were collected after dis-section of the uterus, fixed in formalin, routinely embedded and stained with H. E. for histological evaluation. The different energy forms caused tissue alterations of comparable quality but differing in degree. Most intensive peripheral hyperemia and tissue edema occurred on postoperative days three to seven. Non contact laser irradiation initiated maximal amount of fibrinous exudate. Lesions created with a loop electrode were superficial only and did only affect the endometrium. Preparation with an electrosurgical cutting blade or a laser bare fibre resulted in craterlike lesions lined by carbonisation and did involve deeper layers of the myometrium. The lesions caused by non contact laser irradiation affected all layers of the uterine wall. Three weeks postoperatively, reepithelization of the luminal epithelium was completed. The depth of thermal injury and coagulative necrosis, inflammatory reactions and scar formation was greater in lesions created by laser application compared with those set with a loop electrode at power densities comparable to those usually achieved at hysteroscopic surgery. The results suggest that an electrosurgical loop designed for operative hysteroscopy may be a reliable tool for diathermic resection of pathological endometrial structures like uterine cysts characterized by minimal thermal injuries and a short period of reconvalescence. Non contact laser irradiation may result in deep thermal injuries with the risk of delayed uterine perforation but may be profitable for treatment of partly intramural structures like an intramural leiomyoma.  相似文献   

8.
This study compared the collateral tissue damage and incisional bridging with granulation tissue via histopathological examination following feline onychectomy performed by radiofrequency (RF) and carbon dioxide (CO(2)) laser. Two cats were euthanized, and their digits were harvested for histopathological evaluation on days 1, 3, and 7 post-onychectomy. Each digit was evaluated for total lesion width, total necrosis width, and degree of edema, hemorrhage, and inflammation. This study found few significant differences in collateral tissue damage between RF and CO(2) laser, but more incisional bridging by granulation tissue was noted with RF for feline onychectomies. These results indicate that RF for feline onychectomy is a reasonable alternative to CO(2) laser in regard to collateral tissue damage and bridging of the incision by granulation tissue. In addition, RF is not accompanied by the strict safety considerations and initial expense of acquisition of a CO(2) laser.  相似文献   

9.
Background: Adult mesenchymal stem cells(MSCs) can be conveniently sampled from bone marrow, peripheral blood, muscle, adipose and connective tissue, harvested from various species, including, rodents, dogs, cats, horses,sheep, goats and human beings. The MSCs isolated from adult tissues vary in their morphological and functional properties. These variations are further complicated when cells are expanded by passaging in culture. These differences and changes in MSCs must be considered prior to their application in the clinic or in a basic research study. Goats are commonly used as animal models for bone tissue engineering to test the potential of stem cells for bone regeneration. As a result, goat MSCs isolated from bone marrow or adipose tissue should be evaluated using in vitro assays, prior to their application in a tissue engineering project.Results: In this study, we compared the stem cell properties of MSCs isolated from goat bone marrow and adipose tissue. We used quantitative and qualitative assays with a focus on osteogenesis, including, colony forming unit, rate of cell proliferation, tri-lineage differentiation and expression profiling of key signal transduction proteins to compare MSCs from low and high passages. Primary cultures generated from each source displayed the stem cell characteristics,with variations in their osteogenic potentials. Most importantly, low passaged bone marrow MSCs displayed a significantly higher and superior osteogenic potential, and hence, will be the preferred choice for bone tissue engineering in future in vivo experiments. In the bone marrow MSCs, this process is potentially mediated by the p38 MAPK pathway. On the other hand, osteogenic differentiation in the adipose tissue MSCs may involve the p44/42 MAPK pathway.Conclusions: Based on these data, we can conclude that bone marrow and fat-derived MSCs undergo osteogenesis via two distinct signaling pathways. Even though the bone marrow MSCs are the preferred source for bone tissue engineering, the adipose tissue MSCs are an attractive alternative source and undergo osteo-differentiation differently from the bone marrow MSCs and hence, might require a cell-based enhancer/inducer to improve their osteogenic regenerative capacity.  相似文献   

10.
Landspraying while drilling (LWD) is an approved disposal method for water-based drilling mud (WBM) systems in western Canada. The mud is applied either on cultivated land, where it is incorporated by cultivation, or on vegetated land where it is not incorporated. This study examined the effects of summer WBM application (0, 15, 20, 40, and 80 m3 · ha?1) on native vegetation properties. Our results indicated that LWD increased bare ground but decreased lichen cover at the 80 m3 · ha?1 rate relative to the untreated control. Nitrogen (N), sulfur (S), and magnesium (Mg) concentrations in aboveground plant tissue increased with increasing LWD rate in samples taken 45 d after WBM application, but these differences disappeared 1 yr after treatment. Increase in tissue concentration of phosphorus (P) with LWD rate, however, was only detected 3 yr after LWD. Nonetheless, these changes in tissue chemistry were not associated with significant changes in biomass yield or species composition. Overall, our results suggest that single WBM applications at rates (≤ 20 m3 · ha?1) commonly used in western Canada, if properly managed, are unlikely to adversely affect native prairie vegetation.  相似文献   

11.
The aim of this study was to compare the clinical and histopathological effects of tripeptide copper complex (TCC) and two different doses of laser application (helium-neon laser, 1 and 3 J cm(-2)) on wound healing with untreated control wounds. Experimental wounds were created on a total of 24 New Zealand white rabbits and topical TCC or laser was applied for 28 days. The wounds were observed daily, and planimetry was performed on days 7, 14, 21 and 28 to measure the unhealed wound area and percentage of total wound healing. Biopsies were taken weekly to evaluate the inflammatory response and the level of neovascularization. The median time for the first observable granulation tissue was shorter (P < 0.05) in the low and high dose laser groups than in the control group (3 and 2.66 vs. 4.5 days), but was not different between the TCC and control groups (4.16 vs. 4.5 days). Filling of the open wound to skin level with granulation tissue was faster (P < 0.05) in the TCC and high dose laser groups than in the control group (14 and 16 vs. 25 days), but was not different between the low dose laser and control groups (23 vs. 25 days). The average time for healing was shorter (P < 0.05) in the TCC and high dose laser groups (29.8 and 30.2 vs. 34.6 days), but was not different between the low dose laser and control groups (33.8 vs. 34.6 days). Histopathologically, wound healing was characterized by a decrease in the neutrophil counts and an increase in neovascularization. The TCC and high dose laser groups had greater neutrophil and vessel counts than in the control group, suggesting a more beneficial effect for wound healing.  相似文献   

12.
Gingivostomatitis (GS) with various patterns of disease may require antiviral therapy, steroids, laser fulguration, immunomodulation drugs, or nonsteroidal anti-inflammatory drugs. The use of cyclosporine as an immunomodulation drug has long-term benefits in reduction of the immunologic events that contribute to GS. Whole-mouth extraction or partial extraction (premolars and molars), with radiographic conformation that all root remnants have been removed, may be the most viable option in nonresponsive and or intractably painful stomatitis in noncompliant cats or dogs. Oral inflammation subsided after extraction without the need for further medication in approximately 70% of the cats from two studies with previous chronic unrelenting oral disease. The combination of immunomodulation with cyclosporine together with laser resection of proliferative tissue should be recommended if extraction of teeth is not desired. Removal of proliferative oral tissues by lasing (carbon dioxide laser) removes the tissue that maybe producing tissue antigens and the area where bacteria are sequestered. The use of anti-inflammatory medications is recommended in the management of GS. Therapeutic success is achieved when there is elimination of proliferative tissue and inflammation.  相似文献   

13.

Background

Tumors of the skin and subcutaneous tissue are the largest group of canine neoplasms. Total excision is still the most effective method for treatment of these skin tumors. For its universal properties the carbon dioxide (CO2) laser appears to be an excellent surgical instrument in veterinary surgery. Laser techniques are alternatives to traditional methods for the surgical management of tumors. The aim of this study was to compare various types of laser techniques in skin oncologic surgery: excision, ablation and mixed technique and to suggest which technique of CO2 laser procedure is the most useful in particular case of tumors in dogs.

Findings

The study was performed on 38 privately-owned dogs with total number of 40 skin tumors of different type removed by various CO2 laser operation techniques from 2010–2013. The treatment effect was based on the surgical wound evaluation, the relative time of healing and possible local recurrence of the tumor after 3 months post surgery. Local recurrence was observed in two cases. The study showed that in 30 cases time needed for complete resection of lesions was less than 10 minutes. Time of healing was longer than 12 days in 6 cases (42.8%) with tumor excision and in 14 cases (87.5%) where excision with ablation technique was performed.

Conclusions

The advantages of the CO2 laser surgery were better hemostasis, precision of working, non-contact dissection, less instruments at the site of operation and minimum traumatization of the surrounding tissues.  相似文献   

14.
OBJECTIVE: To develop a technique for neodymium:yttrium-aluminum-garnet (Nd:YAG) laser ventriculocordectomy in standing horses and document healing in horses undergoing laser ventriculocordectomy. ANIMALS: 6 horses between 2 and 32 years old. PROCEDURE: Under endoscopic guidance, the left laryngeal ventricle was everted with grasping forceps and excised with an Nd:YAG laser, using 60 watts of power in a noncontact fashion (6,403 to 9,197 Joules). Following removal of the ventricle, the vocal cord was photoablated. Horses were examined endoscopically 2, 7, 14, 21, 30, and 47 days after ventriculocordectomy, and 1 horse was euthanatized on each of these days. At necropsy, the larynx was removed intact and examined grossly. Samples were collected for histologic examination of the ventriculocordectomy site. RESULTS: Endoscopic examination revealed granulation tissue by day 7, the start of epithelialization by day 21, and healing by day 47. At necropsy, 4 horses were found to have a small amount of ventricular mucosa remaining dorsally and 1 additional horse was found to have a mucocele. Granulation tissue was identified grossly and histologically in the horses euthanatized between 7 and 30 days after surgery. Incipient reepithelialization was evident histologically on day 14, and complete reepithelialization of the surgery site was evident by day 47. CONCLUSION AND CLINICAL RELEVANCE: Results suggest that ventriculocordectomy can safely be performed with an Nd:YAG laser in standing horses.  相似文献   

15.
Low level laser therapy (LLLT) is frequently used in the treatment of wounds, soft tissue injury and in pain management. The exact penetration depth of LLLT in human tissue remains unspecified. Similar uncertainty regarding penetration depth arises in treating animals. This study was designed to test the hypothesis that transmission of LLLT in horses is increased by clipping the hair and/or by cleaning the area to be treated with alcohol, but is unaffected by coat colour. A LLLT probe (810 nm, 500 mW) was applied to the medial aspect of the superficial flexor tendon of seventeen equine forelimbs in vivo. A light sensor was applied to the lateral aspect, directly opposite the laser probe to measure the amount of light transmitted. Light transmission was not affected by individual horse, coat colour or leg. However, it was associated with leg condition (F = 4.42, p = 0.0032). Tendons clipped dry and clipped and cleaned with alcohol, were both associated with greater transmission of light than the unprepared state. Use of alcohol without clipping was not associated with an increase in light transmission. These results suggest that, when applying laser to a subcutaneous structure in the horse, the area should be clipped and cleaned beforehand.  相似文献   

16.
A study was undertaken to determine if it might be possible to prepare tissue sections on slides without the use of paraffin embedding, microtome sectioning, or cryostat sectioning which involve equipment and training not always available to scholars or professionals wishing to examine tissue microscopically. After evaluating many different reagents, cutting instruments and solid supports, we developed a method involving application of super glue to a slide, adhering a section of tissue to it, cutting the tissue with a disposable microtome blade, staining the tissue and removing the superglue with a commercially available product. The sections are similar to those sectioned on a microtome, but do not at this time equal their quality. However, histoarchitecture is preserved and individual cell morphology is usually good. We conclude that this is a viable method for preparing histology sections without the use of a microtome or cryostat, something long thought impossible. We have dubbed the method 'RAMP' (Rapid Adhesive-Mediated Procedure).  相似文献   

17.
低聚果糖是一种新颖的食品添加剂,生理功效良多,随着低聚果糖在食品工业中的应用范围不断扩大,利用现代检测技术对食品中低聚果糖的添加情况进行监测具有必要性.本文系统地综述了近年来国内外检测食品中低聚果糖的方法,包括高效液相色谱法、离子色谱法等较常用方法,以及基质辅助激光解吸离子化质谱法、气相色谱-质谱法等技术;并总结了各方法的性能及优缺点.以便为食品中低聚果糖的有效、快速检测提供参考.  相似文献   

18.
Despite increasing numbers of veterinarians incorporating lasers into their clinical practices, little information has been published about laser clinical applications in soft tissue surgery. This article reviews soft tissue interaction, describes laser equipment and accessories commonly marketed to veterinarians, and discusses clinical applications of the carbon dioxide laser in a systems-based approach. A table of recommended laser tips and settings based on the authors' experiences using a carbon dioxide laser (AccuVet Novapulse LX-20SP, Bothell, WA) is provided.  相似文献   

19.
A mature castrated male domestic shorthair cat was referred for treatment of an excoriated, ulcerated area on the nasal planum. Undifferentiated squamous cell carcinoma was diagnosed. Surgical resection of the nasal planum was not an option, so the lesion was treated 4 times with neodymium:yttrium-aluminum-garnet laser. Laser surgery results in uniform photovaporization of large volumes of tissue. Although treatment with laser does not yield tissue specimens suitable for histologic evaluation, it can result in a cosmetically suitable appearance and can extend the predicted life span. A diagnosis of undifferentiated squamous cell carcinoma has a guarded prognosis: however, the cat of this report survived more than 18 months.  相似文献   

20.
藜麦是藜科植物,能适应不同类型的土壤和气候条件,它富含蛋白质、脂类、纤维、维生素和矿物质,必需氨基酸含量均衡,营养价值高,引起了动物营养学家的广泛关注.藜麦的蛋白质种类中不含谷蛋白,这一特性使乳糜泻患者能使用它.尽管藜麦具有这些特性,但由于进口谷物成本高,且关于其在动物生产上的研究有限,限制了其作为饲料原料在动物上的应...  相似文献   

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