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At least 667 records · Page 37Linked to original sources
PubMed1986

[Effectiveness of various methods of stopping hemorrhage in spleen and liver injuries--results of an animal experiment study].

In 40 wistar rats liver and spleen were traumatized under standardized conditions. The hemorrhage was stopped by four different methods: 1. traditional suture technique with 4 X 0 Catgut, 2. fibrin glue, 3. endocoagulation according to Semm and 4. infrared-coagulation according to Nath.--The results show that the infrared-coagulation was the best schedule for a quick and safe bloodclotting in order to stop the hemorrhage sufficiently Concerning the postoperative lesions the infrared-coagulation had the best results also. On the other hand it could be demonstrated that this method has disadvantages with regard to the histological findings of repair mechanisms. There were deep and large areas of necrosis after infrared--as well as thermo-coagulation. The histological findings of the fibrin gluing technique, however, showed that after a few days of operation a new soft tissue grew into the traumatic lesion. Necrosis could not be identified.--If there is only short time in order to stop the hemorrhage of a parenchymatous organ we emphasize the infrared-coagulation as a favorite method because of the advantages in handling, clotting time and postoperative lesions. If there is more time in order to stop the hemorrhage we favorite the fibrin glue.

Animals↗
PubMedDate not supplied

[Infrared photocoagulation, cryosurgery and laser surgery in hemorrhoidal disease].

The non invasive treatment of hemorrhoidal disease has the best indications for I and II degree symptomatic piles and only in few cases of III and IV degree. Authors report their practice with infra-red-coagulation, cryosurgery and laser surgery, discussing indications, controindications and describing in detail their technique. About laser surgery they emphasize that this procedure is a formal hemorrhoidectomy, and laser acts as a scissor or a blaude.

Hemorrhoids↗
PubMedDate not supplied

[Preventive laser coagulation of the retina in children with uveitis].

Presented are cases of proliferative uveitis in which a laser coagulation of the retina has been performed in order to separate the fibrous changes. The authoresses discuss 2 groups: treated without coagulation and with the use of an argon laser coagulation. They see better anatomical and functional results in group in which prophylactical coagulation has been performed. They draw on this basis the conclusion that it should be used earlier, before the complications which hinder this operation come forth.

Adolescent↗
PubMed2000

Comparison of the effects of in-vivo thermal ablation of pig liver by microwave and radiofrequency coagulation.

Microwave and radiofrequency coagulation is frequently used for the treatment of hepatic tumors. However, differences between these types of therapy have not been clearly demonstrated so far. We performed both types of thermal ablative treatment on pig liver, and compared the size and shape of the coagulated areas produced. The effects of combining both treatments and interrupting hepatic blood flow were also evaluated. The liver of an anesthetized pig was thermally coagulated, with or without interruption of hepatic blood flow, using a needle electrode at 40 W for 150 s with 2450-MHz microwaves and/or with a 460-kHz radiofrequency current. The diameters of the coagulated areas in the liver were 20 +/- 3 mm (mean +/- SD; n = 4) after microwave coagulation and 28 +/- 3 mm following radiofrequency coagulation when blood flow was not interrupted, whereas they were 31 +/- 2 mm and 37 +/- 3 mm, respectively, when blood flow was interrupted. When these treatments were combined sequentially, the diameters of the lesions were 43 +/- 3 mm and 29 +/- 2 mm with and without blood flow interruption, respectively. The ellipticity of the coagulated area, as measured by the largest-to-smallest ratio of its diameters, was 2.3 +/- 0.4 after microwave coagulation and 1.1 +/- 0.1 following radiofrequency coagulation. We conclude that radiofrequency coagulation produces a larger and more spherical coagulated area in the liver (P < 0.01) than does microwave coagulation. The lesion becomes larger (P < 0.05) with both treatments when hepatic blood flow is interrupted during the treatment. The sequential combination of these treatments produces a much larger lesion (P < 0.05) than that produced by either treatment alone.

Animals↗
PubMed1987

Tumor regression after photocoagulation of malignant melanomas of the choroid: an ultrasonographic study.

Ultrasonography was performed in 24 eyes harboring malignant melanomas of the choroid to study tumor regression after xenon-arc photocoagulation at periodic intervals after each photocoagulation session. Ophthalmoscopically, 20 (83%) eyes revealed a complete regression of the tumor after 3 months to 3 years of treatment. However, ultrasonography revealed complete tumor regression in only 13 (65%) out of these 20 eyes while the remaining 7 (35%) 9 eyes had a residual tumor prominence of 0.75-1 microsecond. 14 (70%) out of 20 tumors were completely regressed 1 year after photocoagulation treatment. Most of the eyes revealed complete disappearance of the tumor after 3-5 photocoagulation sessions. Though 4 tumors which did not respond to photocoagulation treatment were located in the central temporal retina within the vascular arcade, no statistically significant difference could be seen between tumor regression and location of the tumor. Complete tumor regression was seen in 4 out of 5 eyes after encircling coagulation alone while 16 out of 19 eyes revealed complete tumor regression after addition of direct treatment of the tumor. Photocoagulation appeared to be a useful tool in the treatment of small choroidal melanomas.

Adolescent↗
PubMed1988

Accommodative weakness and mydriasis following laser treatment at the peripheral retina.

Transient accommodative paresis and pupillary disturbances are some of the less known and uncommon complications of peripheral retinal laser treatment extending over at least one third of the retinal periphery. They are the result of damage by the laser applications to parasympathetic nerve fibers that lie beneath the coagulated area and innervate the ciliary body and iris sphincter. Six myopic patients who suffered from these complications following peripheral laser treatment for retinal tears are presented. A mechanism of direct damage to ciliary muscle fibers during photocoagulation is proposed.

Accommodation, Ocular↗
PubMed1989

[The effect of melanin and hemoglobin on the dye laser photocoagulation in pigmented and albino rabbits].

Photocoagulation was performed in pigmented and albino rabbits using four different wave-lengths of the dye laser (577 nm, 590 nm, 610 nm and 630 nm), and each photocoagulated lesion was examined histologically. The 577 nm dye laser produced chorioretinal coagulation in albino rabbits, which was almost the same as that in pigmented rabbits. This result confirmed that the 577 nm dye laser was well absorbed by hemoglobin in the choriocapillaris, and could produce the sufficient coagulation even if there was no melanin pigment. The 590 nm dye laser produced chorioretinal coagulation in albino rabbits, but it was weaker than that in pigmented rabbits. It was considered that this was because the absorption by hemoglobin of the 590 nm dye laser was less than that of the 577 nm dye laser. The 610 and 630 nm dye laser could not yield appropriate coagulation in albino rabbits under the same conditions as in the 577 nm dye laser. More intense coagulation, that is longer duration and higher power, was required to make chorioretinal coagulation in albino rabbits using the 610 and 630 nm dye laser. In photocoagulation of normal fundus, melanin is the main substance of laser absorption, but in various disorders lacking melanin, the differences of the hemoglobin absorption rate becomes important.

Animals↗
PubMed1991

Argon beam coagulation is superior to conventional techniques in repair of experimental splenic injury.

Present management of splenic trauma focuses on splenic preservation. However, conventional operative techniques for splenic salvage are time consuming and frequently ineffective. The purpose of this study was to assess the efficacy of the argon beam coagulator (ABC) in the management of experimental splenic injury. Ten adult miniature pigs were randomized to treatment with either conventional surgical techniques (topical Surgicel, electrocautery, suture-ligation, digital pressure) or splenic repair with the ABC. Three standard splenic injuries were made in each pig: capsular avulsion, splenic laceration, and hemisplenectomy. The ABC was more effective in treating all three types of splenic injury. The time required to achieve hemostasis and total operative time were significantly less in the group treated with the ABC for all three types of splenic injuries (p less than 0.05, Student's t-test, two sided). Operative blood loss was significantly less in the group treated with ABC for avulsion and hemisplenectomy (p less than 0.05, Student's t-test, two sided). Recurrent bleeding was significantly higher in the group treated with conventional techniques (p less than 0.001, Fisher's exact test, two-sided). We conclude that the argon beam coagulator is more effective than conventional techniques in treating experimental splenic injuries. The ABC provides more rapid and reliable hemostasis. Clinical trials using the ABC for splenic injury are warranted.

Animals↗
PubMed1992

Infra red coagulation for bleeding mucosal telangiectasia.

The technique of infra red coagulation is well suited to the destruction of superficial blood vessels in the skin and/or mucosal surfaces. A method is described here for the destruction of resistant bleeding telangiectasia of the palate and lip in Osler-Weber-Rendu syndrome.

Diathermy↗
PubMed1990

Thermal side reactions during in vitro contact cyclophotocoagulation with the continuous wave Nd:YAG laser.

We compared the effects of continuous wave Nd:YAG laser irradiation on the ciliary body and sclera of enucleated porcine eyes produced by two means of transmission: contact coagulations via a quartz fiber (core 600 microns), and noncontact coagulations via a focussing handpiece. Application times ranged from 10 ms to 1.5 seconds. During contact coagulations using plane fiber tips the temperature at the fiber tip, due to deposits of carbonized tissue, sometimes increased markedly, increasing the risk of perforation. Clinical application of the contact method using plain fiber tips is not recommended.

Animals↗
PubMed1989

Endoscopic laser therapy for watermelon stomach.

Thirteen patients (9 women, 4 men) with anemia from acute and chronic gastrointestinal bleeding were found to have antral vascular disease consistent with watermelon stomach. The median age was 73 yr, with a range of 54-88 yr. Eight of the patients were transfusion-dependent, requiring a median of 5.5 U within the 12 mo before treatment. All were treated with endoscopic neodymium:yttrium-aluminum-garnet laser coagulation. Endoscopic and hematologic improvement were evident in 12 patients available for follow-up after a median period of 6 mo. There was a median increase of 4 g/dl in hemoglobin concentration; thus, the need for transfusion was eliminated. No major complications were encountered. Laser coagulation for watermelon stomach appears to be safe and efficacious and may be a therapeutic alternative for this disorder.

Aged↗
PubMed1992

Rubeosis iridis and neovascular glaucoma: I. Etiopathogenesis and treatment--the present state of the problem.

Rubeosis iridis is one of the severest complications of the occlusive diseases of retinal vessels associated with retinal hypoxia. In the pathogenesis of rubeosis, the author emphasizes the chronicity of retinal hypoxia which leads to the production of the vasoproliferative substance. This so-called vasoproliferative factor then induces the new formation of vessels on the retina, the optic disc, the iris and the anterior chamber angle. Neovascularization of the anterior chamber angle then very often results in the development of the prognostically very unfavourable neovascular glaucoma. It shows that the most effective methods of treatment of rubeosis iridis are the so-called coagulation techniques-panretinal photocoagulation or cryocoagulation. By application of these techniques, we achieve the destruction of the anatomical substrate which is responsible for the production of the vasoproliferative substance, and the result is involution of rubeosis on the iris and in the anterior chamber angle.

Glaucoma, Neovascular↗
PubMed1985

Trans-spectral organic dye laser photocoagulation.

Clinical research utilizing the yellow, orange, and red wavelengths of the dye laser (Rhodamine 6G and MD-631) appears to have considerable promise and may demonstrate that the liquid organic dye laser is the laser of choice for photocoagulation of many types of ocular defects. The effectiveness of the dye laser as a photocoagulation source is due to the trans-spectral availability of relatively high output power wavelengths. Therefore, a target tissue can be selectively coagulated with minimal laser energy transmitted through the refractive media and minimal damage to nearby normal tissues. The dye laser, as a photocoagulation system, should prove valuable in the therapy of many ocular diseases.

Angiomatosis↗
PubMed1987

Proliferative retinopathy and toxemia of pregnancy.

Retinopathy occurring during toxemia of pregnancy generally shows the features of hypertensive retinopathy. The authors describe the case of a patient with bilateral peripheral neovascularizations following toxemia of pregnancy. The likely pathogenesis is ascribed to the development of ischemic areas, which can be determined by microthrombus formation. Presently, low-grade disseminated intravascular coagulation is considered very important in the pathogenesis of toxemia of pregnancy. After panretinal fluorangiography, a selective photocoagulation of ischemic areas was performed. The regression of neovascularizations was observed after one month. No similar case report could be found in the literature.

Adult↗
PubMed1978

[10 years' experience with our department for diabetic retinopathy (author's transl)].

A report is given on 10 year's experience with 2500 diabetic patients, who were followed up and treated in a special department for diabetic retinopathy at the 1st Vienna University eye clinic. The criteria for treatment of diabetic retinopathy by means of photocoagulation, intrascleral diathermy-coagulation and vitrectomy or a combination of these treatment methods are outlined. The fluorescein angiogram served as the basis for the technic of photocoagulation used in a particular case of diabetic retinopathy and for the evaluation of the success of this treatment.

Ambulatory Care↗