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At least 685 records · Page 38Linked to original sources

PubMed1989

[Treatment of preretinal retrohyaloidal hemorrhage: value of early argon laser photocoagulation].

Within the first three or four days after occurrence of a premacular subhyaloidal hemorrhage, the posterior vitreous boundary layer may be lacerated by argon laser coagulation in such a way that the blood flows into the vitreous body, where it is absorbed within a few weeks. Older premacular hemorrhages under an intact vitreous boundary layer, typically green-white in color, have to be treated by more invasive vitreosurgical procedures.

Adult↗

PubMed1991

Mural repair following obliteration of aneurysms. Part III: Pathomorphological effects of Nd:YAG laser on aneurysm obliteration.

Twenty-four experimental aneurysms were created in rat carotid arteries using the venous pouch technique. Four to twelve weeks later, these aneurysms were totally obliterated by the external application of Nd:YAG laser. The aneurysmal dome and neck were both exposed to the laser using low amplitude (1-2 W) at continuous or repeat intervals (0.3 sec on/0.1 sec off). Small aneurysms were easily obliterated without external signs of necrosis, whereas aneurysms larger than 2 mm required complete coagulation resulting in a charcoal-like appearance. At varying intervals (30 min, 7 days, 3 weeks, 6 weeks), the obliterated aneurysms were harvested and evaluated using the scanning electron microscope and standard histological techniques. The results indicate that the effects of the laser on the aneurysm and parent vessel are similar to those encountered following the application of bipolar coagulation with massive coagulation necrosis of the aneurysmal neck and dome. Notably, however, the extension of this process onto the parent vessel involving especially the endothelium surrounding the aneurysm orifice (commonly seen with bipolar coagulation) is minimal following laser coagulation. There appears to be a protective effect on the parent vessel endothelium by blood flow through the vessel. On this basis, it appears that the laser may be an alternative method of aneurysmal coagulation; the use of laser entails less manipulation of the aneurysm. The Nd:YAG laser may be a useful adjunct in the surgical obliteration of clinical cerebral artery aneurysms, especially small ones.

Aneurysm↗

PubMed2004

Bifocal esophageal and rectal cancer palliatively treated with argon plasma coagulation.

Primary multiple neoplasms make a serious diagnostic and therapeutic problem. They occur infrequently; however, they must be considered in the diagnosis as the detection of simultaneous neoplastic foci requires change of therapeutic approach. We present a case of a patient with synchronous esophageal and rectal cancer treated at the Department of Surgery. Because of the advanced neoplastic process and concomitant diseases, the patient was qualified for minimally invasive procedures with recanalization using argon plasma coagulation to avoid injuring palliative procedures and to improve quality of life. The patient died of the primary disease without symptoms of gastrointestinal tract obstruction.

Adenocarcinoma↗

PubMedDate not supplied

Quantitation of colonic injury from argon laser, neodymium: YAG laser and monopolar electrocautery applied to flat mucosa and small sessile polyps of the canine colon.

This study determined the optimum laser energy for ablation of colonic mucosal lesions and small sessile polyps in the canine colon. Neodymium (Nd):YAG laser, argon laser, and monopolar electrocautery were applied to exposed canine colonic mucosa for various application times at various power settings. At the minimum energy level necessary to ablate mucosa, the Nd:YAG laser caused greater muscularis injury than the argon laser and monopolar electrocautery. At higher energy levels, monopolar electrocautery and Nd:YAG laser caused greater muscularis injury than argon laser. Small surgically created polyps in the canine colon were ablated endoscopically with the three energy sources. Single-session complete polyp ablation occurred most frequently with Nd:YAG laser and least frequently with argon laser. The depth of tissue injury beneath polyp ablation sites was least with argon laser and greatest with Nd:YAG laser. This study suggests that the argon laser is safer than the Nd:YAG laser or monopolar electrocautery for coagulation of flat colonic mucosal lesions. Although the argon laser is safer for the coagulation of small sessile colonic polyps, it may be less effective than monopolar electrocautery or the Nd:YAG laser for the single-session fulguration of polyps greater than 5 mm in diameter.

Animals↗

PubMed1988

[Use of plasma surgical devices for hemostasis during operations on the liver and spleen].

A comparative analysis of the efficiency of coagulation of the wound surfaces of the liver and spleen by plasma jet of argon, neon and helium was made. The coagulation rate was shown to increase with the elevation of temperature and power of the plasma jet. Results of the experimental studies have shown that using argon is most expedient for achieving reliable and rapid hemostasis.

Animals↗

PubMed1980

[Risks associated with photocoagulation in proliferative diabetic retinopathy (author's transl)].

In 185 diabetics with proliferative diabetic retinopathy (d.r.) involving both eyes symmetrically we analyzed the indication for photocoagulation in borderline cases in which, despite complications (such as inducement of vitreoretinal retraction), the beneficial effect of photocoagulation outweighs the likelihoood of a spontaneous deleterious course. In stage 2 of proliferative d.r. the risks associated with photocoagulation (i.e., factors likely to cause traction phenomena) were found to be extensive coagulation of intraretinal and preretinal hemorrhages, and coagulation of feeder vessels as well as of fundus areas located behind vitreal hemorrhages. In stage 3, procoagulative risk factors in the morphological picture comprised the existence of several vitreoretinal insertions with tent-shaped traction folds and extensive preretinal and subvitreal hemorrhages.

Diabetic Retinopathy↗

PubMed1980

[Medullary thyroid carcinoma metastasizing to the choroid, ciliary body and iris: clinical and pathological findings in two cases (author's transl)].

Two cases (four eyes) of medullary thyroid carcinoma with metastases in the choroid, ciliary body and iris are described for the first time. In one eye the choroidal metastases were destroyed clinically by photo- and cryocoagulation. In another eye coagulation of a tumor may have facilitated transscleral extension into the orbit. The clinical conclusions arising from the pecularities of these tumors are discussed. It is particularly striking that in 2 patients with this rare tumor metastases developed in the anterior uvea in all four eyes.

Carcinoma↗

PubMed1990

[Dye laser photocoagulation treatment for experimental subretinal neovascularization. 1. Histopathological findings of healing process].

To clarify the healing process of subretinal neovascularization (SRN) histopathologically following laser photocoagulation treatment, we performed laser photocoagulation for experimental SRNs produced in rhesus monkey eyes. To produce long-lasting SRNs, 0.5M 1-ornithine hydrochloride solution was injected intravitreously 2 weeks after photocoagulation. These SRNs were treated a 590nm dye laser, and examined clinically and histopathologically at 24 hours, 2 weeks, 3 months. Histopathologically, new vessels in the subretinal space were coagulated intensely and disappeared during the course of healed lesion. In these lesions, the retinal pigment epithelial cells proliferated in the subretinal space after the disappearance of the SRNs and covered the scar tissue. In strongly coagulated lesions, glial cells were related to the formation of scar tissue. These results showed that closure of new vessels was necessary for the healing of SRNs by photocoagulation and proliferation of the retinal pigment epithelial cells and glial cells occurred during their healing process.

Animals↗

PubMed1989

[Treatment of retinal neovascularization secondary to branch vein occlusion with argon laser photocoagulation].

20 cases (22 eyes) of retinal neovascularization (RNV) secondary to branch vein occlusion were treated with argon laser photocoagulation. The RNV and the area of nonperfusion in these eyes were detected by fluorescein angiography. The results showed that argon laser photo coagulation was a highly effective therapy for RNV which was refractory to treatment. Photocoagulation minimized or resolved RNV and prevented recurrent vitreous hemorrhage. The relationship of RNV with the area of nonperfusion, the selection of the direct or indirect modality, and the points of note for success and prevention of complications were discussed.

Adult↗

PubMed1995

Comparison of hemorrhoidal treatment modalities. A meta-analysis.

PURPOSE: The purpose of this study was to assess whether any method of hemorrhoid therapy has been shown to be superior in randomized, controlled trials. METHOD: A meta-analysis was performed of all randomized, controlled trials assessing two or more treatment modalities for symptomatic hemorrhoids. Outcome variables included response to therapy, need for further therapy, complications, and pain. RESULTS: A total of 18 trials were available for analysis. Hemorrhoidectomy was found to be significantly more effective than manual dilation of the anus (P = 0.0017), with less need for further therapy (P = 0.034), no significant difference in complications (P = 0.60), but significantly more pain (P < 0.0001). Patients undergoing hemorrhoidectomy had a better response to treatment than did patients treated with rubber band ligation (P = 0.001), although complications were greater (P = 0.02) as was pain (P < 0.0001). Rubber band ligation was better than sclerotherapy in response to treatment for all hemorrhoids (P = 0.005) as well as for hemorrhoids stratified by grade (Grades 1 to 2; P = 0.007; Grade 3 hemorrhoids, P = 0.042), with no difference in the complication rate (P = 0.35). Patients treated with sclerotherapy (P = 0.031) or infrared coagulation (P = 0.0014) were more likely to require further therapy than those treated with rubber band ligation, although pain was greater after rubber band ligation (P = 0.03 for sclerotherapy; P < 0.0001 for infrared coagulation). CONCLUSION: Rubber band ligation is recommended as the initial mode of therapy for Grades 1 to 3 hemorrhoids. Although hemorrhoidectomy showed better response rates, it is associated with more complications and pain than rubber band ligation, thus should be reserved for patients who fail to respond to rubber band ligation.

Hemorrhoids↗

PubMed2002

[Normal doses of visible light can cause mutations in skin].

Therapeutic and undesired effects of long-wave (UVA1) (340-400 nm) and visible light were studied. Mutagenicity were investigated after repeated doses encountered in normal situations in the sun. Laser treatment of naevus flammeus was studied with a new 600 nm laser. Also, the effect of photodynamic therapy on cutaneous lymphomas was reported. Both UVA1 and visible light can induce mutations in normal skin after repeated doses. The findings indicate that clothing, not sunscreens, should form the basis of sun protection. In selected cases, the new 600 nm laser may be advantageous in the treatment of naevus flammeus. Localized cutaneous lymphoma may be effectively treated with photodynamic therapy.

Animals↗

PubMed1991

[Retinal photocoagulation in hemorrhagic retinal branch vein thrombosis. A new treatment technique].

In branch vein occlusions involving the macula, the loss of macular function cannot be due to hypoperfusion of the involved capillaries, because if this were so the uninvolved part of the macula would presumably be unimpaired. The impairment of the macula is explained as follows. Congestion of the blood caused by the thrombosis means that the capillaries are exposed to high blood pressure. In the border zone of the thrombotic area capillaries that are normally drained are exposed to capillary hypertension. For this reason, the border zone of a retinal thrombosis is also affected. The perifoveal capillary network is usually in this border zone. We treated branch vein occlusions by perimacular photocoagulations on the blood in the inner retinal layer within the zone of the thrombosis. Our explanation for the gain in visual acuity following this procedure is that we occlude the retinal capillaries that are, passing on the high pressure into the perifoveal capillaries. Our proposed photocoagulation procedure is restricted to cases in which hemorrhage has led to enough blood in the inner retinal layer to coagulate. The destruction of the nerve fiber layer by this kind of photocoagulation has to be taken into account. The possible gain of visual acuity has to be balanced against the loss of function caused by destruction of parts of the nerve fiber layer.

Blood Pressure↗

PubMed1987

[Treatment of suppurative mastitis using laser irradiation and continuous electric current].

Laser radiation and direct electric current were used in the complex therapy of acute suppurative mastitis. The wound cavity was treated by a focussed laser till the appearance of a coagulation crust followed by galvanization of the mammary gland. Such an approach to the associated application of the laser radiation and electric field of direct current is justified pathogenetically and increases the efficiency of treatment of suppurative mastitis.

Electric Stimulation Therapy↗

PubMed1986

Bipolar electrocoagulation versus Nd-YAG laser photocoagulation for upper gastrointestinal bleeding lesions.

Nd-YAG laser photocoagulation and bipolar electrocoagulation may be useful for controlling upper gastrointestinal bleeding or preventing rebleeding from ulcers with visible vessels. To determine if one of these methods is superior to the other, data from a small randomized trial and from a nonrandomized experience were evaluated. Altogether, 33 patients underwent 37 coagulation sessions; 19 of the patients were randomized (8 laser and 11 bipolar). In the randomized group, 47.4% had no rebleeding after therapy (laser = 37.5% and bipolar = 54.5%, P greater than 0.1). In the nonrandomized group 56.8% had no further bleeding. Eleven (33%) of the patients required surgery. No patients died of bleeding or complications related to the study. From these data and those in the literature, it is concluded that the Nd-YAG laser and the bipolar coagulator are equally effective for the treatment of solitary upper gastrointestinal bleeding lesions. Since the bipolar unit is cheaper and more easily transported than the laser unit, it may be the method of choice for cauterizing upper gastrointestinal sources until a more effective method is developed.

Adult↗

PubMed1989

Evaluation of the functional results after different techniques for treatment of retinal detachment due to macular holes.

A total of 50 eyes with retinal detachment due to macular holes were treated in the period from July 1986 to December 1987. In all, 10 eyes underwent pneumatic retinopexy using plain room air. A total of 30 eyes were treated by pars plana vitrectomy, followed by fluid/air exchange, with no treatment of the macular break; in 9 of these the detachment recurred, reflattening of the retina by air tamponade followed by laser photo-coagulation. The other 10 eyes underwent pars plana vitrectomy followed by silicone oil tamponading because of proliferative vitreoretinopathy (PVR). This paper compares the functional results for each group. The parameters used included visual acuity, color vision and visual fields.

Adult↗

PubMedDate not supplied

[Nyctometric studies in argon laser coagulation in patients with diabetic retinopathy].

Forty-two patients (57 eyes) with diabetic retinopathy at various stages have been examined by nyctometry before and over the course of the follow-up period after argon laser coagulation of the retina. The findings evidence a marked reduction of the adaptation ability of the central retinal area even in high vision acuity in the patients with diabetic retinopathy vs. normal subjects. A stable rise of the nyctometric parameters has been observed after argon laser coagulation; these parameters characterize the function of the pigmented epithelium and of the retinal cone, and these data may be considered as an evidence of the improved trophics of these tissues, resultant from such therapy.

Adult↗

PubMed2005

Infrared coagulator: a useful tool for treating anal squamous intraepithelial lesions.

PURPOSE: The incidence of invasive anal squamous carcinoma in men who have sex with men is rising, particularly in those with human immunodeficiency virus. As in the cervix the high-grade squamous intraepithelial lesion is thought to be an invasive squamous cell carcinoma precursor. Cervical high-grade squamous intraepithelial lesions are treated by removing the squamocolumnar transition zone. This is not possible in the anus, where treatment is often surgical and is accompanied by significant pain and morbidity. Better office-based techniques to treat anal high-grade squamous intraepithelial lesions are needed. We employed the infrared coagulator in an office setting to ablate high-grade squamous intraepithelial lesions. METHODS: A retrospective review of medical records was performed on 68 human immunodeficiency virus-positive men who have sex with men who underwent infrared coagulator ablation of biopsy-proven high-grade dysplasia from the time we began using the procedure in 1999. All patients have had at least six months of follow-up. Procedures were performed with local anesthesia on patients with discrete high-grade squamous intraepithelial lesions. Follow-up consisted of anal cytology with high-resolution anoscopy and biopsy of suspicious areas every three to six months. New or recurrent high-grade dysplasia was retreated. Patients with circumferential or bulky disease were treated in the operating room and were excluded from the study. RESULTS: Altogether, 68 patients met the enrollment criteria. The median patient age was 41 years (range 29-62 years). A total of 165 lesions were treated (mean 1.6 lesions, range 1-5) and only 46 (28 percent) persisted. However, 44 patients (65 percent) developed a new or persistent high-grade squamous intraepithelial lesion within a median time of 217 days (range 27-566 days) after infrared coagulation. The remaining 24 patients (35 percent) were free of high-grade dysplasia for a median of 413 days (range 162-1313 days) after infrared coagulation. When patients were treated a second or third time, the incidence of new or persistent high-grade dysplasia dropped to 58 percent and 40 percent, respectively. The probability of curing a retreated lesion was 72 percent. Using generalized estimating equations, the incidence of high-grade dysplasia decreased with repeated infrared coagulator treatments. No patient developed squamous-cell carcinoma, had a serious adverse event, or developed anal stenosis. CONCLUSIONS: The infrared coagulator is a safe, office-based modality for treating anal high-grade squamous intraepithelial lesion in human immunodeficiency virus-positive men who have sex with men. Successive treatments led to decreased recurrence rates.

Adult↗

PubMed1983

Comparison of infrared coagulation and rubber band ligation for first and second degree haemorrhoids: a randomised prospective clinical trial.

One hundred and thirty seven previously untreated out-patients with first and second degree haemorrhoids were allocated at random to treatment by infrared coagulation (n=66) or rubber band ligation (n=71). Complete follow up was obtained in 122 patients (60 who had undergone infrared coagulation (group 1), and 62 rubber band ligation (group 2)) at periods from three months to one year after completion of treatment. Infrared coagulation produced a satisfactory outcome in 51 patients (85%): 34 were rendered asymptomatic and 17 improved. Rubber band ligation produced a satisfactory outcome in 57 patients (92%): 33 were rendered asymptomatic and 24 improved. Both methods were equally effective in first and second degree haemorrhoids. The incidence of side effects, particularly discomfort, during and after treatment was significantly higher in those treated by rubber band ligation (p less than 0.001). This appeared to be an appreciable deterrent to future patient compliance. The number of patients losing more than 24 hours from work was higher after rubber band ligation than after infrared coagulation. The number of treatments necessary to cure symptoms did not differ significantly between the two methods. Infrared coagulation was significantly faster than rubber band ligation (p less than 0.001). Infrared coagulation is a simple, fast, and effective outpatient method for the treatment of first and second degree haemorrhoids with fewer troublesome side effects and higher patient acceptability than rubber band ligation.

Adult↗