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Este trabalho apresenta um modelo bidimensional do olho humano para investigar a evolução da temperatura em estado transitório e o dano térmico associado nas camadas do olho e, principalmente, no melanoma de coroide. A modelagem e simulação computacional foram executadas para um paciente portador de um melanoma de coroide, submetido a um tratamento por irradiação com laser. Para determinar o campo de temperaturas, foi desenvolvido um modelo que utiliza a equação da biotransferência de calor de Pennes (BHTE - Bioheat Transfer Equation) que possui um termo de fonte/sumidouro que responde pelo calor transferido através da perfusão sanguínea. O modelo de Birngruber foi utilizado para determinar a função dano térmico durante a termoterapia transpupilar a laser (TTT). A análise foi efetuada a partir de uma imagem de ultrassom do paciente. Este tipo de exame forneceu as dimensões do olho e do tumor. O software comercial de CFD (Computational Fluid Dynamics) FLUENT, que emprega o Método dos Volumes Finitos (MVF), foi utilizado nas análises do modelo. Foram calculadas as temperaturas em estado estacionário para o olho não irradiado e estes resultados foram utilizados como condição inicial para a simulação de estado transitório para o olho irradiado, durante 60 segundos, com um laser de diodo (810 nm e potências de saída de 178, 222, 400 e 500 mW) cujos feixes apresentavam diâmetros de 2,0 e 3,0 mm e intensidades de 56.588 W/m² e 70.736 W/m² sobre a córnea. Para validar o modelo, os resultados das temperaturas, em estado estacionário para o olho não exposto à radiação do laser, foram comparados com outros mostrando uma boa concordância entre eles. Os resultados das temperaturas e do dano térmico, estado transitório, para o olho irradiado com o laser estão, qualitativamente, em acordo com a literatura disponível.
This paper presents a two-dimensional model of the human eye to investigate the evolution of temperature in transient state and the associated thermal damage in the layers of the eye and, especially in the choroidal melanoma. The computer modeling and simulation were performed for a patient with a choroidal melanoma, undergoing treatment by laser irradiation. To determine the temperature field, we developed a model that uses the Pennes Bioheat Transfer Equation (BHTE) that has a term of source/sink that responds to the heat transferred through the blood perfusion. The Birngruber model was used to determine the function of thermal damage during the laser transpupillary thermotherapy (TTT). The analysis was carried out from an ultrasound image of the patient. This type of examination provided the dimensions of the eye and the tumor. The CFD (Computational Fluid Dynamics) commercial software FLUENT&®, which uses the Finite Volume Method (FVM) was used in the analysis of the model. The temperatures, steady-state, were calculated for the normal eye, i.e, without laser irradiation and these results were used as initial condition for the simulation of transient state to the eye irradiated for 60 seconds with a diode laser (810 nm and output power of 178, 222, 400 and 500 mW) whose beam had a diameter of 2.0 to 3.0 mm and irradiance of 56,588 and 70,736 W/m² on the cornea. To validate the model, the results of temperatures, in steady state to the eye not exposed to laser radiation, were compared with others showing a good agreement between them. The results of thermal damage and transient state, for the eye irradiated by the laser, show that the values of damage depth are in agreement with the literature.
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AIM: To report a case of wet age-related macular degeneration (AMD) treat with multiple transpupillary themotherapy (TTT) and choroidal neovascularization (CNV) disappeared but retinal pigment epithelial(PRE) and choroidal atrophy occurred with a low vision at the end point.METHODS: Clinical data including fundus hotographs, fundus fluorescein angiography (FFA), indocyanine angiography (ICGA) and optical coherence tomography(OCT) was reviewed.RESULTS: A 72-year-old man complained about blurred vision of his left eye and FFA revealed polypoidal choroidal vasculopathy (PCV) in the macula. His left eye had stable vision of 0.1 for 6 years without any treatment of CNV. About 2 years later, his right eye presented a piece of CNV. During the period of 3 years, the lesion remained more (3×5 PD) and less (1×2PD) in size with remarkable exudates and bleeding, and 7 sessions of TTT were applied with 80-280mW, 2mm of spot, and 60 seconds exposure and with the interval of 3 months or more. The CNV lesion finally disappeared, but there left a white area in the macula and vision decreased from 0.3 to 0.04.CONCLUSION: Although CNV lesion can be eliminated by TTT, obvious atrophy of RPE cells and the choroids can happen and this may not be of help for patient vision. It suggests that the parameters of TTT will be lower than 120 mW/mm and limited less two sessions if applicable, especially for Asia people.
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Objective To investigate the approach and effect of PDT and TTT therapeutic alliance for isolated choroidal angioma according to the lication. Methods After mydriasis,through 90D retinal mirror examination ,fluorescein fundus angiography (FFA) ,Indocyanine green angiography (ICGA) and ultrasound,the diagnosis of angiography choroidsal hemangioma was made. Position:peripapillary , six cases( tumors locating only in macula fovea were not included in this statistical area). OCT suggested that epithetlial tumors from the surface of nerve macular were affected. Period of the disease was between one week and two months . Preoperative best corrected vision acuity range was 1. 05 ～ 0.4. By ultrasonography, tumors thickenss was from 2.2mm to 4mm, and diameter was from 6.6mm to 11.2mm. OCT indicated that the height of neural epithetlium breaking away from macular area was between 156mm and 486mm. inferior retinas separated two months after morbidity. TTT was partly applied to cure tumor body ortside macdular area with IRIS Medical OculightSLX gallium arsenicde laser(810nm). Energy:per light spot shining diameter was 1 mm, and the power was between 150mw to 250mW, and time was 60s. Therapeutic standard was retinal surface changing to pale. Choroids shrunk back and retinal ptgment epithetlium prolixferated in TTT therapy area;recheck 2 weeks later. If FFA showed that active macula fovea pathological changes were not cured, PDT was performed as following :689nm laser was used , and veteporfin ( comm. ercial name : Visudyne) was injected by intravenous at a speed of 6mg/mm~2 , and 15 minutes later, the laser was irradiated for a period of 83 ～ 126s. For tumors with thicdness under 3mm,one light spot was irradiated for 83s;for rumors with thicdness above 3mm, acouple light apot was irradiated for 125s. A small quantity of hyperpigmintation occurred in the limbus,luteus retinae at the second week of follow up. All the cases were followed up for 3 months to 12 months. Results The final vision reached 0.1 ～ 1.0. OCT showed that the earliest complete recovery of limbus luteus retinae neural epithetlium was at the third week, and for another 3 cases,the recovery was at the 4th week. One case with detachment of retina partial recovered 3 months after treatment. OCT suggested that most of the macular detachment and epithetlial cystic degenerateion of neurons recovered to normal. type - B ultrasound was performed in the first three months of treatment. The tumors were difficult to be detected in two cases, and four cases had a thickness of 0. 8 ～2.2mm. At the 6th month,the detection of tumors for the six cases showed normal results. PDT was used only once in the included six cases. Conclusion PDT and TTT therapeutic alliance for isolated choroidsal angioma is safe and effective at special position of eye ground. Each treatment showed its unlque adventages in this combination with a reduction of frequentcy and cost of expensive cost of PDT, and satisfying results of the shrink of the rumors and improvement or preservation of vision.
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PURPOSE: To evaluate the effects of transpupillary thermotherapy(TTT) for several intraocular tumor. METHODS: The 5 intraocular tumors (2 capillary hemangioma, 1 metastatic tumor, 1 retinal angioma, 1 melanocytoma) were treated with transpupillary thermotherapy. We compared preoperative visual acuity, size, fundus finding, ultrasonogram to postoperative data. RESULTS: The one capillary hemangioma and metastatic tumor were improved in fundus finding. The other tumors were not improved. The visual acuity of patient with metastatic tumor was improved from F.C/30cm to 0.15. CONCLUSIONS: Transpupillary thermotherapy was effective tool for intraocular tumors. We may need the guideline for treatment of intraocular tumor by using transpupillary thermotherapy.
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Humans , Hemangioma , Hemangioma, Capillary , Hyperthermia, Induced , Retinaldehyde , Ultrasonography , Visual AcuityABSTRACT
The purpose of this study is to make clear comprehensive relationship between Thymol turbidity test values (TTT) and the dietary intakes of nutrients. The subjects of this study were 287 young healthy people in Tokushima prefecture.<BR>The results of the survey were as follows:<BR>1) In males, multiple regression analysis showed that variables which correlated best with the TTT values were dietary intakes of sugar energy and vegetable protein aged 30-49 years, and dietary intakes of animal fat and energy aged 50-69 years.<BR>2) In females, multiple regression analysis showed that variables which correlated best with TTT values were dietary intakes of animal protein and vegetable fat aged 50 69 years, but there were no statistically significant correlation between TTT values and the dietary intakes of nutrients aged 30-49 years.
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We observed 32 cases of viral hepatitis who were admitted to to pediatric ward of Korea General Hospital for 1 year from Oct. 1979 to Sept. 1980 and the following results are obtained. 1) Eight among 32 eases of viral hepatitis are positive for HBsAg in their serum samples tested by solid phase radioimmunoassay. 2) High ESR is found in 69.6% of cases with type A hepatitis. In type B hepatitis ESR within normal limit is 87.5% of cases. 3) Values for GPT are higher than those of GOT in 70.8% of patients with type A hepatitis. In type B hepatitis GOT higher than GPT are 87.5% of cases. 4) Elevated levels of TTT are observed in 83.4% of patients with type A hepatitis. In type B hepatitis TTT within normal limit is 75.0% of casses. We may conclude that ESR, SGOT, SGPT and TTT can be a very useful additional test as a diagnostic aid in the differentiation of the two types of viral hepatitis, when tested early in the disease.