Low energy fluence CO2 laser treatment of lymphangiectasia

Lymphangiectasia is an uncommonly reported complication of lymphatic insufficiency. These dilatations of lymphatic vessels may be symptomatic, necessitating treatment. While CO2 laser ablation has been used with success in the treatment of lymphangiectasia, it is infrequently reported and previous laser protocols have relied on high irradiances. The successful use of low fluence CO2 laser in the treatment of multiple lymphangiectases on the lower limb of a middle-aged Caucasian woman with unilateral chronic lymphoedema is described.     

Microendoscopic treatment of the hypopharyngeal diverticulum with the CO2 laser

BACKGROUND AND OBJECTIVE: The hypopharyngeal (Zenker's) diverticulum is a herniation of mucosa and submucosa on the posterior wall of the pharynx. The only treatment is surgical. STUDY DESIGN/MATERIAL AND METHODS: Between 1976 and 1993, 109 patients with a hypopharyngeal diverticulum were operated on at the Department of Otorhinolaryngology, Head and Neck Surgery, University of Kiel, either transcutaneously combined with a cricopharyngeal myotomy (n = 76), or microendoscopically (n = 37) using the CO2 laser. Results and complications of both techniques were evaluated and compared. RESULTS: With both surgical procedures, > 90% of the patients were treated successfully. The rate of postoperative complications was generally low. In comparison to the microendoscopic procedure, serious complications were found to be more frequent in patients treated with the conventional transcutaneous diverticulectomy. CONCLUSION: The laser surgical tissue bridge dissection is a less invasive, quick, relatively safe, and effective procedure requiring only short hospitalisation. Therefore, the laser surgical tissue bridge dissection can be considered as the method of choice for the treatment of the hypopharyngeal diverticulum.     

CO2 laser surgery in osteomyelitis

Spirituality is a critical component of the holistic mind-body-spirit model embraced by Hospice. Hospice chaplains, as part of the caregiving team, must understand their abilities and limitations in providing spiritual guidance to others who may differ in religious and spiritual beliefs.     

CO2 laser conization for cervical intraepithelial neoplasia grade II-III: complications and efficacy

PURPOSE: Functional outcome after anterior resection for rectal cancer is improved by colonic J-pouch reconstruction compared with straight anastomosis. The indications for colonic J-pouch reconstruction have yet to be determined. Therefore, we attempted to determine the level at which J-pouch reconstruction provides an advantage over straight anastomosis. METHODS: A total of 48 patients who underwent 5-cm colonic J-pouch reconstruction (J-pouch group) and 80 patients who underwent straight anastomosis (straight group) underwent functional assessment one year postoperatively. RESULTS: The functional outcome in the J-pouch group was significantly better than that in the straight group when the distance of the anastomosis from the anal verge was less than 8 cm. The difference was particularly obvious when the level of the anastomosis was below 4 cm. However, functional outcome in the straight group when the anastomosis was between 9 and 12 cm from the anal verge was also satisfactory and did not differ from that in the J-pouch group when the anastomosis was between 5 and 8 cm from the anal verge. CONCLUSIONS: Colonic J-pouch reconstruction is indicated when the distance of anastomosis from the anal verge is less than 8 cm, and it is essential when the distance is less than 4 cm.     

Effects of rapid pulsed CO2 laser beam on cortical bone in vivo

Twenty rabbit femurs were used to study the effect of CO2 laser on cortical bone. Sixteen femurs were treated with 20 watts, 3 mm defocused beam, 2 KHZ spike pulse mode CO2 laser for 10 seconds through a circular window in the metaphysis. In four control femurs, the inner cortex was exposed without laser treatment. The animals were killed at 4 and 6 weeks and the specimens studied histologically. All laser-treated specimens showed thermal changes. Three histological zones were observed. A superficial zone of inner cortex close to the beam consisted mainly of carbonization or carbon ash during resorption. An intermediate zone consisted of bone necrosis and healing with associated areas of new bone formation. The deep zone of outer cortex had normal bone with no cellular damage. No such changes were observed in the control specimens. The CO2 laser can be used to generate a controlled zone of tissue ablation, which may make it a potentially useful tool for tumor margin cauterization.     

CO2 laser and Gianturco stent for endoscopic treatment of tracheal stenosis

Spectroscopic studies of antibody-antigen interactions can provide useful information about the interactive motifs and energetics involved in the intermolecular association process. In this study we used absorption spectroscopy to examine the interactions between five different monoclonal antibodies (mAb) and four superpotent ligand sweeteners. Quantitative changes in the absorption spectra in the wavelength range of 230-800 nm were utilized for the determination of intrinsic association constants and thermodynamic parameters of the mAb-ligand complexes. The intrinsic association constants for the mAb-ligand complexes were found to be in the range of 10(7)-10(5) lM-1 and were in agreement with previous radioimmunoassay determinations. For two mAb, qualitative changes in the spectra in the 340 nm range could be identified and were related to the presence of charge-transfer interaction between the guanidinium ligand and aromatic residues in the binding site of the mAb. A charge transfer spectra was observed in mAb NC10.8 with two different sweetener ligands. The thermodynamic parameters of the ligand-mAb interactions were analyzed by van't Hoff plots and in almost all cases the reactions were found to be enthalpically driven. The determinations of intrinsic affinity and thermodynamic parameters may be useful in computer-aided molecular modelling studies of the antibody binding pocket and predicted ligand docking orientations. Antibody NC6.8 was found to react with this set of sweetener ligands in a rank order that is related to their sweetness potencies and the spectroscopic findings for NC6.8 are in agreement with the X-ray diffraction data of the Fab-ligand crystal structures.(ABSTRACT TRUNCATED AT 250 WORDS)     

Endoscopic treatment of Zenker's diverticulum using CO2 laser. 17 cases

OBJECTIVES: Various treatment regimens have been used for the management of Zenker's diverticulum. These include surgery (transcervical diverticulectomy, myotomy) and endoscopic treatment with rigid instruments or flexible endoscope. The aim of this study is to report the results of the treatment of Zenker's diverticulum with rigid endoscope applied CO2 laser and to compare them with other types of treatment. PATIENTS AND METHODS: Between May 1991 and November 1996, 17 patients (8 males, 9 females) with symptomatic Zenker's diverticulum underwent endoscopic treatment under short general anesthesia applied CO2 laser. The mean age of the patients was 73.2 years (range: 54 to 97 yrs). All patients had significant symptoms such as dysphagia (15 patients out of 17). All patients were clinically evaluated after the procedure. RESULTS: The endoscopic incision was performed in one session per patient. Symptoms and dysphagia disappeared in all patients except one (dysphagia). Two complications (one cervical emphysema, one fistula) were managed clinically. Mortality was 0%. Mean follow-up was 17 months. There was no recurrence of dysphagia, all patients remained asymptomatic. CONCLUSIONS: Rigid endoscopic treatment of symptomatic Zenker's diverticulum applied with laser CO2 is an efficient and safe method. It should be considered as an alternative therapy for Zenker's diverticulum, especially for patients at a high surgical risk.     

Outpatient treatment of obstructive sleep apnea syndrome with CO2 laser: laser-assisted uvulopalatoplasty

To find a safe and convenient method for the treatment of obstructive sleep apnea syndrome, 89 outpatient cases were treated with CO2 laser-assisted uvulopalatoplasty. All cases had been diagnosed and observed with polysomnographic monitoring. The result of 89 cases of OSAS was judged as good in 67 cases (75.7%). Only 6 cases had a little bleeding during operation, no other complication has been encountered.     

Fire hazards and CO2 laser resurfacing

The purpose of this study was to investigate the fire risk of laser resurfacing in the presence of supplemental oxygen. This study aims at defining safety parameters of variables such as laser energy level, oxygen flow rate, and "oxygen to laser target distance" when oxygen is delivered through a nasal cannula or nasopharyngeal tube. The typical operating room environment was simulated in the laboratory using the Yucatan minipig animal model. The energy source was a Coherent Ultrapulse CO2 laser. It was found that combustion did not occur at laser settings of 500 mJ, 50 W, 100 kHz, and a density of 5, used in conjunction with an oxygen flow rate of 6 liter/minute with the target area as close as 0.5 cm to the oxygen delivery. A total of 400 computer pattern generator treatments were delivered using this energy setting without observation of any combustion (p < 0.001). This provides evidence that while using even somewhat high laser settings and oxygen flow rate, laser induced fires can be avoided. We conclude that use of the laser in the presence of oxygen is safe, provided the target area is free of combustible fuels. Despite this assurance, laser mishaps are serious because they lead to both morbidity and mortality. It is our recommendation that close attention be constantly paid to all details, thus reducing the hazard potential of laser energy on local factors in an oxygen-rich environment.     

An epithelial exclusion technique using the CO2 laser for the treatment of periodontal defects

When treating osseous defects associated with periodontitis, the healed result is a compromised regeneration of the attachment apparatus from epithelial downgrowth. This article demonstrates a laser ablation technique for excluding the epithelium from contacting the root surface of the periodontal wound. In accordance with the principles of guided tissue regeneration, the epithelium should be excluded for at least 30 days after surgical therapy. A series of case reports demonstrate the technique and the 6-month results that can be obtained using this approach. The regenerated tissue is confirmed through reentry procedures and radiographs.     

Clinical studies of TMR with the CO2 laser

OBJECTIVE: This paper reviews the current status of transmyocardial laser revascularization by a carbon dioxide laser. SUMMARY: Since 1990 over 3000 patients worldwide have been treated with a carbon dioxide laser. A nonrandomized phase II trial was completed in 1995. A randomized controlled phase III trial has completed enrollment, and analysis of the follow-up is pending. METHODS: In each trial 200 patients with endstage coronary artery disease and severe disabling angina that was not amenable to conventional revascularization were enrolled. Preoperative evaluation included confirmation of angina class and evidence of reversible ischemia based on myocardial perfusion scans. Repeat evaluations were done postoperatively at 3, 6 and 12 months. RESULTS: 80% of the patients showed a significant improvement in angina class status postoperatively and 30% had no angina at one year of follow-up. Concomitant with this there was significantly less ischemia noted on follow-up perfusion scans. CONCLUSIONS: Early results from nonrandomized and randomized controlled trials of transmyocardial laser revascularization by carbon dioxide laser indicate that this technique provides angina relief and improved perfusion in patients with end-stage coronary artery disease.     

Skin tightening effects of the ultrapulse CO2 laser

The authors evaluated the relative importance of the following scanning parameters at computed tomographic bronchoscopy in an anesthetized adult sheep's thorax: section thickness (2, 4, 8 mm), pitch (1.0, 1.5, 2.0), milliampere setting (100, 175, 250 mA), and overlap of reconstructed sections (0%, 25%, 50%, 75%). Five blinded readers ranked the images twice in comparison with photographs of the mounted specimen. Differences in image quality were significant (P < .001) with section thickness of 2 mm and a pitch of 1.0. The milliampere setting had only a minor effect on image quality, and a 50% overlap of reconstructed sections was best.