The carbon dioxide laser: an alternative surgery technique for the treatment of common cutaneous tumors in dogs

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.     

Evaluation of healing following frenectomy

Aberrant frenum attachment would cause plaque accumulation and malalignment of teeth. It can be managed by frenotomy or frenectomy methods, through a conventional surgical technique or laser technique. Therefore, it is of interest to compare frenectomy healing surgical and laser techniques. Data from 51 outpatients and post-operative healing of frenectomy was assessed by Landry’s healing score index using 3 weeks postoperative photographs followed by statistical analysis. Based on the healing score index, the laser technique showed better outcomes than the surgical technique. Moreover, the association between the management of high frenal attachment and the healing score index was found to be statistically significant.     

The effect of low-intensity laser irradiation in the blue, green, and red spectral ranges on healing of experimental skin wounds in rats

The effects of low-intensity laser irradiation in the red (632.8 nm), green (532 nm), and blue (441.2 nm) spectral ranges on wound healing has been studied in rats. The effect of the traditionally used red laser irradiation has been compared with the effect caused by laser irradiation in other spectral ranges, aiming to support the provisional hypothesis that a similar healing effect could be achieved at lower doses of wound irradiation by lasers emitting in the blue and green spectral ranges. The following parameters have been used to characterize healing of the experimental wounds: the functional activity of phagocytes in the wound exudate, which was determined from luminol-dependent chemiluminescence, the phagocyte number; the wound exudates’ antioxidant activity; and the rate of healing, which was determined as the change of the wound surface area. It was found that in all cases the laser irradiation accelerated the healing of wounds. Exposure to red laser irradiation at the dose of 1.5 J/cm²), and to blue or green laser irradiation at a dose of 0.75 J/cm² shortened the time of the wound healing from 22 to 17 and 19 days, respectively. The functional activity of leukocytes in irradiated groups increased by day 5 after surgery, whereas in the control group it decreased. The superoxide dismutase activity increased in all experimental groups by day 5 after surgery. Laser irradiation in the red spectral range at a dose of 1.5 J/cm² resulted in a larger increase in superoxide dismutase activity, as compared to that found after exposure to laser irradiation in the blue and green spectral ranges at a dose of 0.75 J/cm².     

Laser tissue welding in ophthalmic surgery

Laser welding of ocular tissues is an alternative technique or adjunct to conventional suturing in ophthalmic surgery. It is based on the photothermal interaction of laser light with the main components of the extracellular matrix of connective tissues. The advantages of the welding procedure with respect to standard suturing and stapling are reduced operation times, lesser inflammation, faster healing and increased ability to induce tissue regeneration. The procedure we set up is based on the use of an infrared diode laser in association with the topical application of the chromophore Indocyanine Green. Laser light may be delivered either continuously or in pulses, thus identifying two different techniques that have been applied clinically in various types of transplants of the cornea. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Laser surgery: using the carbon dioxide laser.

In 1917 Einstein theorized tha through an atomic process a unique kind of electromagnetic radiation could be produced by stimulated emission. When such radiation is in the optical or infrared spectrum it is termed laser (light amplification by stimulated emission of radiation) light. A laser, a high-intensity light source, emits a nearly parallel electromagnetic beam of energy at a given wavelength that can be captured by a lens and concentrated in the focal spot. The wavelength determines how the laser will be used. The carbon dioxide laser is now successfully employed for some surgical procedures in gynecology, otorhinolaryngology, neurosurgery, and plastic and general surgery. The CO2 laser beam is directed through the viewing system of an operating microscope or through a hand-held laser component. Its basic action in tissue is thermal vaporization; it causes minimal damage to adjacent tissues. Surgeons require special training in the basic methods and techniques of laser surgery, as well as in the safety standards that must be observed.     

A comparative study of the effects of laser and light-emitting diode irradiation on the wound healing and functional activity of wound exudate leukocytes

The effects of coherent He-Ne laser and non-coherent light-emitting diode radiation on rat skin wound healing and functional activity of wound excudate leukocytes were compared. A comparative pathomorphological analysis showed that the He-Ne laser and light-emitting diode irradiation stimulated the transition of the inflammatory phase of the wound healing into the reparative (proliferative) and scarring phases sequentially. It was also detected that the functional activity of leucocytes changed in a dose-dependent manner. The leukocyte activity was found to be similar in the groups with laser and light-emitting diode irradiation. Thus, we can conclude that coherent laser and non-coherent light-emitting diode radiation have very close effects on wound healing and activity of wound exudate leukocytes, and coherence is not required for this activity.     

Proteomic analysis of human tears: defensin expression after ocular surface surgery

Human tear protein profiles were monitored by surface enhanced laser desorption/ionization-time-of-flight mass spectrometry ProteinChip technology (SELDI-TOF ProteinChip) and liquid chromatography-mass spectrometry (LC-MS). Tears were collected from 21 patients scheduled for surgery to remove an ocular surface neoplasm prior to surgery (day 0) and on days 1, 3, and 30 postoperatively. Using this proteomic approach, we verified that three human alpha-defensins (HNP-1, HNP-2, and HNP-3) were significantly up-regulated in their expression after surgery and that their levels decreased to approximately normal by day 30 by which time healing was complete. Further confirmation of the identity of the alpha-defensins in human tears was made by LC purification, trypsin digestion, and ESI-MS/MS analysis of their tryptic digests. The concentrations of HNP-1 and HNP-2 were determined and shown to be markedly increased after ocular surface surgery. The results of the study suggest that human alpha-defensins HNP-1, HNP-2, and HNP-3 are up-regulated after surgery, and may in addition to their antimicrobial properties have an important role in wound healing.     

A study of the effect of low-intensity laser radiation of the blue, green, and red spectral regions on the healing of experimental skin wounds in rats

The effect of low-intensity laser radiation of the blue (441.2 nm), green (532 nm), and red (632.8 nm) spectral regions on the healing of experimental skin wounds in rats has been studied. The effect of the traditionally applied laser radiation in the red region has been compared with the effect of laser radiation in the other spectral regions, assuming that, upon irradiation of wounds by lasers emitting in the blue and green regions, a similar effect can be achieved at lower doses. The following parameters characterizing the healing of experimental wounds were used: the functional activity of phagocytes of wound exudates, which was determined by luminol-dependent chemiluminescence, and their number; the antioxidant activity of wound exudates; and the rate of healing, which was determined as a change in the wound area. It was shown that irradiation with laser accelerated the healing of wounds in all cases. The exposure to laser radiations in the red (1.5 J/cm), blue, and green (0.75 J/cm2) spectral regions shortened the time of wound healing from 22 to 17 and 19 days, respectively. The functional activity of leukocytes after the exposure increased on day 5 after the infliction of the wound, whereas in the control it decreased. The superoxide dismutase activity increased in all experimental groups by day 5 after the operation. A maximum increase in the superoxide dismutase activity occurred after the exposure to laser radiation in the red region at a dose of 1.5 J/cm and in the blue and green spectral regions at a dose of 0.75 J/cm2.     

Reconstructive surgery for immunosuppressed organ-transplant recipients

Prolonged vascularized organ allograft survival and an improved quality of life are now possible for many transplant recipients. These advances are due largely to greater understanding of the immune response, the development of potent immunosuppressive agents (cyclosporin A), and improved surgical techniques. Thus more of these patients may require surgical procedures related or unrelated to their original operation, and the plastic surgeon, among other specialists, should be aware of the special problems of the immunocompromised transplant recipient who needs to undergo reconstructive surgery. We report our experience with 15 kidney, heart, and liver transplant recipients who required reconstructive surgery for a variety of conditions. The combined team approach by reconstructive and transplant surgeons is described, as well as the perioperative drug protocol and the special problems that immunosuppressed transplant recipients present. We conclude that these patients can successfully undergo major reconstructive procedures as long as the plastic surgeon not only performs technically flawless surgery, but also familiarizes himself or herself with the special problems of the immunosuppressed host, including the ever-present risk of sepsis and delayed and impaired wound healing, the potential for acute Addisonian crisis, and the possibility of multiple complicating comorbid conditions.     

Preparation Strategies for Mg-Alloys for Biodegradable Orthopaedic Implants and Other Biomedical Applications: A Review

Biodegradable materials offer many advantages over the conventionally used non-biodegradable biomaterials. A number of biodegradable material-based (BMB) alloys have been developed for biomedical applications. Such alloys are increasingly used for manufacturing orthopaedic implants. The elimination of secondary surgery depends on the efficacy of the BMB implant which needs to fulfill two essential requirements. While such an implant has to be strong enough to provide adequate support to the damaged structure in skeleton, it should also be capable of maintaining just the right balance between rate of healing of the damaged structure and rate of degradation of the implant. The complexities involved in striking a balance between these two apparently conflicting requirements makes it imperative to optimize the design and preparation strategy of the BMB alloy. Many biodegradable metals, ceramics and polymers have been investigated for this application and the Magnesium (Mg)-based alloys have been found to be amongst the most suited ones. This review focuses on preparation techniques employed in development of Mg – alloys for biodegradable orthopaedic implants (fracture fixation implants). The process can essentially be split into: material optimization, processing techniques, and surface modifications.     

Accelerated wound healing of oral soft tissues and angiogenic effect induced by a pool of aminoacids combined to sodium hyaluronate (AMINOGAM)

In this study we investigated the property of a new medical substance, in the form of a gel compound containing four aminoacids (glycine, leucine, proline, lysine) and sodium hyaluronate (AMINOGAM), to accelerate the wound healing process of the soft oral tissues and to promote angiogenesis in vivo in the vascular proliferation in chick embryo chorioallantoic membrane (CAM) assay. Furthermore, we investigated the capacity of AMINOGAM to induce the expression of an angiogenic cytokine, namely vascular endothelial growth factor (VEGF) in human fibroblasts in vitro. Results showed that AMINOGAM promoted wound healing in post-surgical wounds (after teeth extraction, oral laser surgery with secondary healing without direct suture of the surgical wound, and after dental implant insertion). Stimulated angiogenesis in vivo in the CAM assay and the response was similar to that obtained with vascular endothelial growth factor, a well-known angiogenic cytokine, tested in the same assay, and confirmed by clinical outcomes, which showed reduction of the healing time of oral soft tissues after three different kinds of surgery and also the absence of post-operative infections.     

CO2激光、LD激光联合治疗牙龈瘤46例疗效观察

目的：研究CO2激光、LD激光联合治疗牙龈瘤及保存牙体组织的临床疗效。方法：对46例口腔牙龈瘤患者发病的年龄,性别,好发部位进行分析,采用CO2激光、LD激光联合治疗机,先用CO2激光束切割肿瘤,而后CO2激光气化肿瘤波及牙齿的牙周膜,术后第二天用LD激光,每日一次,每次15分钟,连续5天照射手术创面。结果：46列牙龈瘤患者,42例一次治疗痊愈,4例复发,二次手术后无复发,手术疗效、治愈率100％。结论：CO2激光、LD激光联合切除牙龈瘤与传统的手术方法,治疗疗效机理进行了对照,其特点是保存了肿瘤波及的牙齿,不造成组织缺损,还具有手术时间短,出血少,愈合快等优点。     

Laser blepharoplasty for making double eyelids in Asians

The double-eyelid operation is a cosmetic procedure performed primarily on Asians who have no supratarsal folds. The goal in Oriental blepharoplasty is to ensure a stable double-eyelid fold with predictable and long-lasting results. Candidates for this procedure desire attractive eyelids with a natural-looking fold. Today, the CO2 laser is used as a surgical tool by plastic surgeons, and its use in cosmetic surgery has recently been expanded to blepharoplasties.We used the high-power CO2 laser (UltraPulse; Coherent, Santa Clara, Calif.) in the double-eyelid operation. Between September of 1995 and September of 1999, a total of 241 patients underwent laser double-eyelid operations at Korea University Medical Center and Dr. Choi's Aesthetic Clinic, with an average follow-up of 18 months.By using the CO2 laser, we could create a stable double-eyelid fold with long-lasting results. The rate of fold release was 2 percent, which was less than the rate using the conventional scalpel incision method. The CO2 laser contributed to a reduction in pain or discomfort after the operation; therefore, patient comfort and early recovery could be enhanced after double-eyelid surgery. In the healing of the incision line, it showed mild redness for 3 weeks, but long-term follow-up showed the scar produced by the laser appeared to be equal in quality compared with the conventional method. Laser blepharoplasty is a useful and effective method to create a stable and attractive double eyelid for Asian patients.     

Chirurgie de l’hyperparathyroïdie primaire en 2008

In recent years, different minimally invasive techniques of parathyroidectomy have been described. The concept of these limited explorations is based on the fact that 85% of patients will have a single-gland disease. Minimally invasive techniques are targeted on one specific parathyroid gland and in most cases the exploration of other glands is not performed. These interventions are today possible for three main reasons: the available imaging techniques permit to localize the diseased gland, the use of rapid intraoperative PTH assay can confirm the successful extirpation, new instrumentation and miniaturized cameras have been adapted for this kind of surgery. Not all patients presenting with primary hyperparathyroidism are candidate for this surgery. Contraindications are mainly due to a large goiter, previous surgery in the parathyroid vicinity, suspicious multiglandular disease and equivocal preoperative localization studies. Currently 60% of patients with primary hyperparathyroidism can benefit of these techniques. Studies comparing conventional parathyroid surgery to minimally-invasive techniques have shown a diminution of postoperative pain and better cosmetic results with minimally-invasive techniques. If early results are similar to those obtained with conventional parathyroidectomies, it is still too soon to evaluate what will be the recurrence rate of these new techniques. One can expect that minimally invasive and conventional parathyroid surgery will probably turn out to be complementary in the near future.     

Imaging Cell Membrane Injury and Subcellular Processes Involved in Repair

The ability of injured cells to heal is a fundamental cellular process, but cellular and molecular mechanisms involved in healing injured cells are poorly understood. Here assays are described to monitor the ability and kinetics of healing of cultured cells following localized injury. The first protocol describes an end point based approach to simultaneously assess cell membrane repair ability of hundreds of cells. The second protocol describes a real time imaging approach to monitor the kinetics of cell membrane repair in individual cells following localized injury with a pulsed laser. As healing injured cells involves trafficking of specific proteins and subcellular compartments to the site of injury, the third protocol describes the use of above end point based approach to assess one such trafficking event (lysosomal exocytosis) in hundreds of cells injured simultaneously and the last protocol describes the use of pulsed laser injury together with TIRF microscopy to monitor the dynamics of individual subcellular compartments in injured cells at high spatial and temporal resolution. While the protocols here describe the use of these approaches to study the link between cell membrane repair and lysosomal exocytosis in cultured muscle cells, they can be applied as such for any other adherent cultured cell and subcellular compartment of choice.     

Ultrafast Mid-IR Laser Scalpel: Protein Signals of the Fundamental Limits to Minimally Invasive Surgery

Lasers have in principle the capability to cut at the level of a single cell, the fundamental limit to minimally invasive procedures and restructuring biological tissues. To date, this limit has not been achieved due to collateral damage on the macroscale that arises from thermal and shock wave induced collateral damage of surrounding tissue. Here, we report on a novel concept using a specifically designed Picosecond IR Laser (PIRL) that selectively energizes water molecules in the tissue to drive ablation or cutting process faster than thermal exchange of energy and shock wave propagation, without plasma formation or ionizing radiation effects. The targeted laser process imparts the least amount of energy in the remaining tissue without any of the deleterious photochemical or photothermal effects that accompanies other laser wavelengths and pulse parameters. Full thickness incisional and excisional wounds were generated in CD1 mice using the Picosecond IR Laser, a conventional surgical laser (DELight Er:YAG) or mechanical surgical tools. Transmission and scanning electron microscopy showed that the PIRL laser produced minimal tissue ablation with less damage of surrounding tissues than wounds formed using the other modalities. The width of scars formed by wounds made by the PIRL laser were half that of the scars produced using either a conventional surgical laser or a scalpel. Aniline blue staining showed higher levels of collagen in the early stage of the wounds produced using the PIRL laser, suggesting that these wounds mature faster. There were more viable cells extracted from skin using the PIRL laser, suggesting less cellular damage. β-catenin and TGF-β signalling, which are activated during the proliferative phase of wound healing, and whose level of activation correlates with the size of wounds was lower in wounds generated by the PIRL system. Wounds created with the PIRL systsem also showed a lower rate of cell proliferation. Direct comparison of wound healing responses to a conventional surgical laser, and standard mechanical instruments shows far less damage and near absence of scar formation by using PIRL laser. This new laser source appears to have achieved the long held promise of lasers in minimally invasive surgery.     

Surgical applications of femtosecond lasers

Femtosecond laser ablation permits non‐invasive surgeries in the bulk of a sample with submicrometer resolution. We briefly review the history of optical surgery techniques and the experimental background of femtosecond laser ablation. Next, we present several clinical applications, including dental surgery and eye surgery. We then summarize research applications, encompassing cell and tissue studies, research on C. elegans, and studies in zebrafish. We conclude by discussing future trends of femtosecond laser systems and some possible application directions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

水激光与超声洁治对中度慢性牙周炎的疗效对比

目的:探讨水激光与超声洁治对中度慢性牙周炎的疗效。方法:选取81例中度慢性牙周炎患者,年龄27-62岁,随机分为两组:激光组(41例)采用水激光治疗,超声组(40例)采用超声洁治法治疗。通过患者治疗后1个月,3个月的菌斑指数(plaque index,PLI),牙龈指数(gingival index,GI),牙周袋深度(probing depth,PD),牙周附着水平(clinical attachment level,CAL),治疗过程中的VAS评分等观察指标,对水激光与超声洁治进行疗效对比。结果:与基线各项牙周指数相比,激光组和超声组治疗后1个月,3个月的各项牙周指数均明显降低(P0.05)。与超声组相比,激光组治疗后1个月的GI值明显低于超声组,治疗后1个月和3个月的PD值和CAL值均低于超声组(P0.05)。治疗前,两组VAS评分相比,差异没有统计学意义(P0.05),治疗后,激光组的VAS评分明显低于超声组(P0.05)。结论:水激光治疗中度慢性牙周炎,治疗过程痛觉感受轻微,能轻易清除引起炎症的牙石及菌斑,促进牙周组织愈合。     

Nd:YAG激光治疗特殊部位尖锐湿疣的疗效观察

目的：观察Nd：YAG激光治疗位于尿道口、阴道口、肛门及肛周的难治性尖锐湿疣的疗效。方法：将61例特殊部位的尖锐湿疣的患者随机分为实验组（31例）和对照组（30例）,实验组采用Nd：YAG激光机治疗,对照组采用普通CO2激光治疗机,随访半年观察两组的创面愈合情况、治愈率及复发率。结果：采用Nd：YAG激光治疗的实验组一次治愈率为80．64％,高于对照组的一次治愈率56．67％（x^2=4．087,P〈0．05）,但两组的总治愈率无显著性差异（x^2=1．198,P〉0．05）。实验组复发率为22．58％,低于对照组的复发率46．67％。两者有显著性差异（x^2=3．918,P〈0．05）。激光术后第5天实验组的愈合率45．16％高于对照组的愈合率20．00％,两者有显著性差异（x^2=4．380,P〈0．05）;第7天实验组的愈合率为87．09％高于对照组的愈合率60．00％,两者有显著性差别（x^2=4．469,P〈0．05）;第10天实验组的患者全部愈合,愈合率为100％,高于对照组的愈合率83．33％（P=0．024〈0．05）。结论：Nd：YAG激光治疗特殊部位尖锐湿疣效果好,创面愈合快,复发率低。     

Capillary hemangioma (strawberry mark) of infancy: comparison of argon and Nd:YAG laser treatment

Capillary hemangioma of infancy (strawberry mark) is a self-limiting problem, and conservative treatment is recommended. These birthmarks can be associated with a great deal of morbidity. There is definitely a role for a palliative form of treatment without systemic complications or destruction of adjacent tissue. In a 6-year period, 55 patients received 57 Nd:YAG or argon laser treatments. Thirty patients received 31 argon treatments, and 25 patients received 26 Nd:YAG treatments; and 2 received first argon with subsequent Nd:YAG treatments. Although more dramatic successes were noted in the Nd:YAG laser, complications were more frequent and severe. Complications included delayed healing, postoperative bleeding, and some hypertrophic scarring. Complications were seen in 12 percent of all patients, 9 percent of these associated with the Nd:YAG laser.