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1.
Indian J Ophthalmol ; 2023 Mar; 71(3): 977-982
Article | IMSEAR | ID: sea-224909

ABSTRACT

Purpose: To develop a viable in vivo chorioallantoic membrane (CAM) model to study the growth and invasion of patient?derived retinoblastoma (RB) and choroidal melanoma (CM) xenografts (PDXs). The study utilizes primary tumor samples instead of cancer cell lines, which provides a more authentic representation of tumors due to conserved morphology and heterogeneity. Methods: Fertilized chicken eggs were procured, windowed, and their CAM layers were dropped. On embryonic development day (EDD) 10, freshly cut patient?derived CM and RB tumors were implanted on the CAM layer and the setup was incubated for 7 days. The tumor?embedded CAM layer was harvested on EDD 17, and the extracted tumor samples were subjected to hematoxylin and eosin staining and immunohistochemical analysis to evaluate the extent of tumor invasion. Results: Significant changes in the vascularity around the RB and CM PDXs were observed, indicating an angiogenic environment. The cross?sectional histological view of the tumor implant site revealed the invasion of both the tumors into the CAM mesoderm. Invasion of CM into CAM mesoderm was visualized in the form of pigmented nodules, and that of RB was indicated by synaptophysin and Ki?67 positivity in Immunohistochemistry (IHC). Conclusion: The CAM xenograft model was successfully able to support the growth of CM and RB PDXs and their invasion in CAM, thus presenting as a feasible alternative to mammalian models for studying tumorigenicity and invasiveness of ocular tumors. Moreover, this model can further be utilized to develop personalized medicine by inoculating patient?specific tumors for preclinical drug screening.

2.
International Eye Science ; (12): 1260-1263, 2023.
Article in Chinese | WPRIM | ID: wpr-978615

ABSTRACT

AIM: To investigate the effect of the expression of miR-375 on the proliferation and invasion of choroidal melanoma(CM)MUM-2B cells.METHODS: MUM-2B cells were cultured and were transfected with miR-375 mimic sequence(mimic group), miR-375 inhibitor sequence(inhibitor group), negative control group and no treatment(blank group). The qRT-PCR, CCK-8, apoptosis and Transwell experiments were used respectively to detect the expression of miR-375, cell proliferation activity, apoptosis, cell migration and invasion.RESULTS: Compared with the negative control group(1.01±0.10)and the blank group(1.03±0.07), the expression level of miR-375 in the cells of the mimic group(2.65±0.15)was increased, while the expression level of miR-375 in the cells of the inhibitor group(0.28±0.06)was decreased(P<0.05). Compared with the blank group and negative control group, the OD values of the cells in the mimic group at 24, 48, 72, and 96h were decreased(P<0.05), while the OD values of the cells in the inhibitor group at 24, 48, 72, and 96h were increased(P<0.05). Compared with the apoptosis rates in the blank group and negative control group, which were(20.54±4.01)% and(22.80±4.28)%, the apoptosis rate in the mimic group(39.11±3.37)% was increased(P<0.05), while it was decreased in the inhibitor group(10.13±2.17)%(P<0.05). Compared with the blank group and negative control group, the number of migration cell and the number of invasion cell in the mimic group were decreased(P<0.05), while the number of migration cell and the number of invasion cell in the inhibitor group were increased(P<0.05). CONCLUSIONS: Up-regulating the expression of miR-375 in MUM-2B cells can reduce cell proliferation activity, accelerate cell apoptosis, and inhibit cell migration and invasion, while down-regulating the expression of miR-375 has the opposite effect. It indicates that miR-375 may play the function of tumor suppressor in the course of CM.

4.
J Cancer Res Ther ; 2019 May; 15(3): 504-511
Article | IMSEAR | ID: sea-213648

ABSTRACT

Aims and Objectives: Brachytherapy using removable ophthalmic plaques loaded with suitable small sealed radioactive seeds adjacent to the ocular's tumor has been widely used as an effective treatment. The aim of this study was to investigate the dose distribution in a modeled eyeball followed to loading of an ocular melanoma tumor with different concentrations of gold nanoparticles (GNPs) as dose enhancement agent by Monte Carlo (MC) calculations. Materials and Methods: The MC code of MCNPX 2.6.0 was used to modeling of COMS standard eye plaque loaded with 24 125I sources (6711 model) located on the sclera of modeled eyeball with detailed structures and materials. A choroidal melanoma tumor was simulated and loaded with different concentrations of spherical gold GNPs (50 nm in diameter). Dose enhancement factors (DEFs) of ocular components were calculated. Results: The dosimetric properties of 125I source (6711 model) and dose distribution of COMS standard eye plaque were calculated successfully as recommended by TG-43U1; AAPM. Loading of tumor with GNPs increased dose to the tumor and decreased dose to the normal tissues; the DEF was increased up to 2.280 and 2.030 for tumor apex, while it was decreased to 0.760 and 0.892 for macula and for gold-tumor mixture and nanolattice distributions, respectively. Conclusion: Loading the choroidal tumor volume with GNPs improves the dose distribution by increasing dose to the tumor and decreasing dose to the health components in ocular brachytherapy with 125I seeds 20-mm COMS plaque

5.
Journal of China Medical University ; (12): 230-235, 2019.
Article in Chinese | WPRIM | ID: wpr-744831

ABSTRACT

Objective To explore the inhibitory effects of miR-15 b-5 p on choroid melanoma cell line proliferation by targeting CDK4.Methods Dual-luciferase assay was used to verify the direct binding site between miR-15 b-5 p and CDK4 3'-UTR. MUM-2 B cells were cultured in vitro and transfected with negative control RNA, miR-15 b-5 p mimics, inhibitor normal control (nc) RNA, and miR-15 b-5 p inhibitor. qRT-PCR was used to detect miR-15 b-5 p expression, Western blotting was used to measure the expression levels of CDK4 in the cells, CCK-8 assay was used to detect proliferation capacity, and flow cytometry was used to detect cell cycle. Results Dual-luciferase assay verified that miR-15 b-5 p could bind to CDK4 mRNA 3'-UTR successfully. Compared to the negative control group, the mimics group showed significantly increased miR-15 b-5 p expression, decreased CDK4 levels, decreased cell proliferation rate, and increased proportion of G1-phase cells. Compared to the inhibitor nc group, the inhibitor group showed significantly decreased miR-15 b-5 p expression (t = 25.01, P < 0.000 1), increased CDK4 protein level, increased cell proliferation rate, and decreased proportion of G1-phase cells.Conclusion miR-15 b-5 p can target CDK4, induce G1 phase arrest in cells, and thus, reduce the proliferation rate of choroid melanoma cells.

6.
Indian J Ophthalmol ; 2018 Oct; 66(10): 1395-1400
Article | IMSEAR | ID: sea-196948

ABSTRACT

Purpose: To report mortality of patients who were eligible for enrollment in the Collaborative Ocular Melanoma Study (COMS) clinical trials of medium-sized choroidal melanoma or large-sized choroidal melanoma but chose to defer treatment or receive no melanoma treatment. Design: Prospective nonrandomized multicenter cohort study as an adjunct to COMS randomized clinical trials. Methods: Patient follow-up procedures included examinations, correspondence, telephone contacts, and National Death Index searches. Primary outcome was patient death measured by all-cause mortality. Secondary outcomes were melanoma treatment and melanoma metastasis. Results: Of 77 patients eligible for COMS clinical trials who chose to defer or receive no melanoma treatment, 61 were appropriate candidates and 45 (74%) enrolled in the natural history study (NHS). In all, 42 patients (42 eyes) had medium melanoma, and the median follow-up was 5.3 years (range, 4–10.7 years). In all, 22 patients (52%) had subsequent melanoma treatment, and 20 (48%) had no melanoma treatment. For the 42 patients, Kaplan–Meier estimate of 5-year mortality was approximately 30% [95% confidence interval (CI), 18%–47%]. For COMS medium melanoma trial, 5-year mortality was 18% (95% CI, 16%–20%), not statistically significantly different from the NHS patients. After adjusting for differences in age and longest basal diameter, the 5-year risk of death for NHS patients versus COMS trial patients was 1.54 (95% CI, 0.93–2.56). Three patients had large melanoma. Melanoma metastasis was confirmed or suspected in 8 (42%) of 19 deaths. Conclusion: Greater mortality and higher risk of death for NHS patients are probative but not conclusive evidence of a beneficial, life-extending effect of medium melanoma treatment.

7.
Indian J Ophthalmol ; 2018 Jan; 66(1): 140-142
Article | IMSEAR | ID: sea-196558

ABSTRACT

Optic disc melanocytoma (ODM) has been considered as a benign tumor with few reports of malignant transformation. We present swept-source optical coherence tomography (SSOCT) imaging of a case of ODM. As attaining histopathology is impossible in most cases, we discuss the possibility of using SSOCT as a tool for ruling out choroidal invasion or juxtapapillary melanoma.

8.
Recent Advances in Ophthalmology ; (6): 519-522, 2018.
Article in Chinese | WPRIM | ID: wpr-699658

ABSTRACT

Objective To construct the eukaryotic expression vector of LDHA with Flag label and detect its effects on the growth of human choroidal melanoma (CM) MUM-2B cells.Methods CM cells line MUM-2B subcultured by the Military Academy of Sciences were divided into two groups:experimental group and control group.The experimental group was transiently transfected with Flag-LDHA plasmid,and the control group was transiently transfected with Flag plasmid.Using the Flag-LDHA with GST label as a template,the LDHA gene was amplified by polymerase chain reaction (PCR),which then was inserted into eukaryotic expression vector of Flag,and the recombinant plasmid Flag-LDHA was identified by bacterial liquid PCR,double enzyme digestion and sequencing,both which were transiently transfected into human CM MUM-2B cells after successful identification,and finally,its expression was determined by Western blot.The biology behaviors of melanoma cell line MUM-2B transfected with Flag-LDHA and Flag plasmid were analyzed by counting Kit-8 (CCK8) assays.Results The coding region sequence of LDHA gene of approximately 1000 bp was harvested from PCR amplification,which was successfully cloned into the Flag vector.Compared with the control group,the PCR result of the bacterial liquid in the experimental group was positive.The double enzyme digestion results showed that eukaryotic expression vector of Flag with a length of about 4000 bp Flag vector and a 1000 bp LDHA gene band.And the sequencing results indicated that the inserted sequence was completely in consonance with the coding sequence of the LDHA gene.Western blot results showed the successful expression of recombinant plasmid Flag-LDHA in MUM-2B melanoma cells.CCK8 assays demonstrated that Flag-LDHA recombinant plasmid could promote the growth of melanoma cell line MUM-2B.Conclusion The eukaryotic expression vector of Flag-LDHA was successfully constructed,which can promote the growth of melanoma cell line MUM-2B.This will lay the foundation for studying the function of LDHA in the initiation and progression of human CM.

9.
Rev. Soc. Colomb. Oftalmol ; 51(1): 79-85, 2018. ilus.
Article in Spanish | LILACS, COLNAL | ID: biblio-912664

ABSTRACT

Objetivo: Exponer las principales características clínicas de un paciente con melanocitoma del nervio óptico, asociado a neurofibromatosis tipo 1 o enfermedad de Von Recklinghausen. Diseño del estudio: Reporte de caso. Método: Se revisó la historia clínica y los reportes de ayuda diagnósticas: Tomografía axial computarizada de orbitas simple y cerebral simple, ecografía ocular, campos visuales, Angiografía fluoresceínica, Tomografía óptica coherente de nervio óptico. Resultados: Se presenta el caso clínico de un paciente de 78 años de edad, con neurofibromatosis tipo 1, quien manifiesta visión borrosa en ojo izquierdo. Se realiza diagnóstico de melanocitoma del nervio óptico, que se caracteriza por ser una lesión altamente pigmentada y de buen pronóstico, con posibilidad de trasformación maligna. Generalmente no asociado con anomalías sistémicas. En la literatura actual no existe reporte de casos en los que se relacione a neurofibromatosis tipo 1. Conclusión: Esta revisión se concentra en exponer las manifestaciones clínicas del melanocitoma del nervio óptico asociado a una enfermedad sistémica, a través de un caso clínico por primera vez reportado en Colombia así como a nivel mundial. La importancia de publicar este reporte es facilitar un diagnóstico precoz, basados en la carente evidencia que existe y así no sea una enfermedad subdiagnosticada.


Purpose: To present the main clinical characteristics of a patient with melanocytoma of the optic disk, associated with neurofibromatosis type 1 also known as Von Recklinghausen's Disease. Study design: Case report. Method: Medical history and diagnostic studies were evaluated: Orbit and cerebral Computed tomography, visual fields, Fluorescein angiography and optic nerve tomography. Results: We present the clinical case of a 78-year-old patient with neurofibromatosis type 1, who manifests blurred vision in the left eye. Diagnosis of melanocytoma of the optic disk is made, this is a highly pigmented lesion with a good prognosis, it has the possibility of malignant transformation. Generally, not associated with systemic abnormalities. In the current literature there is no report of cases in which it is related to neurofibromatosis type 1. Conclusion: This case reviewfocuses on exposing the clinical manifestations of optic nerve melanocytoma associated with a systemic disease, through a clinical case reported for the fi rst time in Colombia as well as worldwide. The importance of publishing this report is to facilitate an early diagnosis, based on the lack of evidence that exists and that is not an underdiagnosed disease.


Subject(s)
Neurofibromatosis 1/epidemiology , Eye Abnormalities , Neurofibromatosis 1/diagnosis , Nevus, Pigmented , Optic Nerve Injuries
10.
Recent Advances in Ophthalmology ; (6): 828-831, 2017.
Article in Chinese | WPRIM | ID: wpr-607218

ABSTRACT

Objective To observe vasculogenic mimicry (VM) of human choroidal melanoma cell line OCM-1 cultured in vitro and the expression of PI3K and EphA2 protein,as well as to explore the possible mechanisms.Methods OCM-1 cells were cultured in vitro and stained with periodic acid Schiff (PAS) on days 7,which aimed to observe the formation of PAS-positive cyclic structures,that is,VM formation.Then immunohistochemical staining was performed to detect PI3K and EphA2 on day 1,4,7 and the results were observed.Ressults On day 4 of 3-demintional culture,most of OCM-1 cells were polygonal and the cytoplasm was abundant;the nuclei were round and the nucleoli were visible.A small part of the tumor cells were long spindle.It was found that several long spindle cells were connected to each other to form hemicyclic structure.After 7 days,a large number of tumor cells became long spindle,growing along the collagen scaffold,and long protrusions appeared,forming a ring structure.PAS staining showed that the tumor cells were mostly arranged in a row,and tumor cells imitated the formation of body blood vessels,resulting in cell band and pipeline-like cell layers,with one layer of extracellular matrix (PAS-positive substance) making up the ring structure.Moreover,the expression levels of PI3K and EphA2 on day 4 and 7 were significantly higher than those on day 1 (all P < 0.05),and their expression levels on day 7 were higher than those on day 4 (all P < 0.05).Conclusion EphA2 and PI3K may play an important role in the VM formation in 3-dimentional culture of human choroidal melanoma cell line OCM-1.

11.
International Eye Science ; (12): 2256-2259, 2017.
Article in Chinese | WPRIM | ID: wpr-669406

ABSTRACT

·Choroidal melanoma ( CM) has the largest number in uveal malignant tumors and is the common intraocular malignant tumor among adults. Its morbidity takes the second place in intraocular malignant tumors in China, following retinoblastoma. This study reviewed pathological feature, pathogenesis, imaging examination and progress on therapeutic research of choroidal melanoma in recent years.

12.
Recent Advances in Ophthalmology ; (6): 1005-1009, 2017.
Article in Chinese | WPRIM | ID: wpr-667532

ABSTRACT

[Absract] Objective To explore a modified method for establishing a rabbit model of B16F10 cells and the factors in tumorigenesis as well as to observe contrastenhanced ultrasonography (CEUS) in qualitative and quantitative evaluation of dynamic circulation pattern of choroidal melanoma.Methods Tumor fragments of choroidal melanoma were implanted into the suprachoroidal space of the right eyes in 10 rabbits,with the left eyes as the controls.After 4 weeks,rabbits eyes were harvested for examined using ultrasonic imaging,color doppler flow imaging,and CEUS,and the images were analyzed with SonoLiver software.Results The proportion of rabbits with choroidal melanoma formation was 80.0%,with 2 cases dead.The maximum major diameter of the tumor was (0.92 ± 0.28) cm and (0.66 ± 0.30) cm.The maximum intensity,rise time,time to peak,mean transit time and area under curve was (263.56 ±143.33)%,(5.01 ± 1.42)s,(6.17 ±2.18)s,(18.01 ±7.56)s,(4505.13 ± 1491.75)% respectively,while the rising slope and descending slope was 59.48 ± 75.18 and-7.21 ±5.76 accordingly.And the peak intensity,area under curve and descending slope of choroidal tumor was larger than those of normal eyes (all P < 0.05),while no significant difference was found in rise time,time to peak,mean transit time and rising slope (all P > 0.05).Conclusion Suprachoroidal implantation of tumor fragments can facilitate the formation of the stable animal model of choroidal melanoma.And CEUS application has a great clinical value in qualitative and quantitative evaluation of blood circulation in melanoma.

13.
Chinese Journal of Medical Ultrasound (Electronic Edition) ; (12): 734-737, 2017.
Article in Chinese | WPRIM | ID: wpr-712021

ABSTRACT

Objective To explore the diagnostic value of ultrasonic elastography in choroidal melanoma. Methods A total of 96 cases (97 eyes) of choroidal melanoma were included in present study from June 2016 to June 2017 in Eye Center of Beijing Tongren Hospital, Capital Medical University. The control group consisted of 18 patients with choroidal hemangioma (18 eyes). All eyes were examined by color Doppler ultrasound and ultrasonic elastosonography. The strain ratio of the tumor and surrounding normal tissue was calculated for each case. By comparing the strain ratio between choroidal melanoma and choroidal hemangioma, the diagnostic value of ultrasound elastography in choroidal melanoma was investigated. Results The strain ratios of the two groups were 39.51±15.79 for choroidal melanoma and 13.15±10.40 for choroidal hemangioma. The independent sample t-test was performed between the two sets of data. The difference of the strain ratio between choroidal melanoma and choroidal hemangioma was statistically significant (t=6.802, P<0.001). Conclusions The stiffness of ocular malignant tumor (choroidal melanoma) is significantly higher than that in intraocular benign tumor (choroidal hemangioma). Ultrasonic elastography can be used as an important examination for the diagnosis and differential diagnosis of choroidal melanoma.

14.
Article in English | IMSEAR | ID: sea-176809

ABSTRACT

AIM: Retrospective study of cases of choroidal melanoma examined at the 1st Department of Ophthalmology, University Hospital American Hellenic Educational Progressive Association, during the 10‑year period, from January 2002 to December 2011. MATERIALS AND METHODS: The study group consists of 84 patients (84 eyes) with newly diagnosed choroidal melanoma. The documentation of the location and the dimensions of the melanomas, based on B‑Ultrasonography findings (apical height, diameter), were included. A total of 58 patients were referred to a specialized center abroad for conservative irradiation therapy. Twenty six eyes were enucleated due to large size of the tumor and the histopathological type was determined. RESULTS: Of the 84 cases, 44 were located at the posterior pole while 40 anteriorly. Based on size, 6% (5/84) were small, 58% (49/84) were medium and 36% (30/84) large. Based on the histopathological analysis of 22 of the 26 eyes enucleated, 36% were mixed‑cell, 32% were spindle cell and 27% were epithelioid cell melanomas. CONCLUSIONS: Our study is the first documentation and classification of newly diagnosed cases of choroidal melanomas. The large number of mandatory enucleations, due to large size, is surprising. Patients need to be better informed about preventive fundoscopy for diagnosis of asymptomatic melanoma at an earlier stage.

15.
Journal of the Korean Ophthalmological Society ; : 1464-1466, 2015.
Article in Korean | WPRIM | ID: wpr-19666

ABSTRACT

PURPOSE: To report the first case of pigmented choroidal metastases without enucleation diagnosed with fine-needle aspiration biopsy. CASE SUMMARY: A 47-year-old male was referred to our clinic with a suspected diagnosis of choroidal melanoma in his left eye. Positron emission tomography-computer tomography used to evaluate systemic metastases revealed lung cancer. Pathology of the detected lung mass was primary lung neuroendocrine tumor. To differentiate choroidal metastasis and primary choroidal melanoma, we performed a fine-needle aspiration biopsy for choroidal tumors. The cytology showed results favoring metastatic atypical carcinoid and the patient was started on systemic chemotherapy. CONCLUSIONS: All pigmented choroidal tumors are not choroidal melanomas and choroidal metastases may be pigmented. The present case suggests that proper systemic evaluation and biopsy for suspected choroidal tumor could be helpful in diagnosis.


Subject(s)
Humans , Male , Middle Aged , Biopsy , Biopsy, Fine-Needle , Carcinoid Tumor , Choroid , Diagnosis , Drug Therapy , Electrons , Lung , Lung Neoplasms , Melanoma , Neoplasm Metastasis , Neuroendocrine Tumors , Pathology
16.
Indian J Ophthalmol ; 2014 Feb ; 62 (2): 158-162
Article in English | IMSEAR | ID: sea-155527

ABSTRACT

Aim: To report our experience of brachytherapy using ‘BARC I‑125 Ocu‑Prosta seeds’ for the management of intraocular tumors with regard to tumor control, globe preservation visual outcome, and patient survival at Sankara Nethralaya, Chennai, India between September 2003 and May 2011. Materials and Methods: We reviewed records of 35 eyes of 35 patients who underwent ophthalmic brachytherapy between September 2003 and May 2011. Twenty‑one cases had choroidal melanoma, nine had childhood retinoblastoma, two had adult‑onset retinoblastoma, and there were one case each of vasoproliferative tumor, retinal angioma, and ciliary body melanoma. Brachytherapy was administered using a 15‑ or 20‑mm gold plaque with or without a notch. Brachytherapy was the primary treatment modality in all tumors other than retinoblastoma, wherein brachytherapy was done post chemoreduction for residual tumor. Results: For choroidal melanomas, the mean radiation dose was 68.69 ± 15.07 (range, 47.72-94.2) Gy. The eye salvage rate was 13/20 (65%) and tumor control rate was 16/20 (80%) at an average follow‑up of 24.43 ± 24.75 (range, 1.5-87.98) months. For retinoblastoma, the mean dose was 45.85 ± 3.90 (range, 39.51-50.92) Gy. The eye salvage rate and tumor control rate was 5/6 (83.3%) at an average follow‑up of 38.36 ± 31.33 (range, 4.14-97.78) months. All eyes with retinoblastoma needed additional focal therapy for tumor control and eye salvage. Conclusion: The results of this retrospective study confirms that the use of ‘BARC I‑125 Ocu‑Prosta seeds’ in episcleral plaques to treat intraocular tumors offers a viable option for the management of intraocular cancers.

17.
Rev. bras. eng. biomed ; 29(1): 57-69, jan.-mar. 2013. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-670974

ABSTRACT

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.

18.
Indian J Ophthalmol ; 2012 Jul-Aug; 60(4): 289-295
Article in English | IMSEAR | ID: sea-144855

ABSTRACT

Context: To analyze the results of episcleral plaque brachytherapy using indigenous Bhabha Atomic Research Centre (BARC) Iodine-125 Ocu-Prosta seeds for the management of intraocular tumors from a single institute. AIM: To report our initial experience and learning curve on the use of ‘BARC I-125 Ocu-Prosta seeds’ for the management of intraocular tumors such as choroidal melanomas, retinoblastomas and vasoproliferative tumors (VPT). Materials and Methods: We retrospectively reviewed 13 eyes of 13 patients who underwent ophthalmic brachytherapy between May 2008 to March 2012. Nine cases had choroidal melanomas; three had retinoblastomas while one case had VPT. Results: For choroidal melanomas the average apical diameter before brachytherapy was 7.6 mm and average largest basal diameter was 12.1 mm, respectively, which reduced to 4.2 mm and 7.7 mm after the procedure at an average follow-up of 24 months (range 10-43 months). Retinoblastoma and VPT also showed good regression after brachytherapy. Conclusion: Plaque radiotherapy using 125I seeds can be performed under peribulbar anesthesia and provides a viable option for the management of intraocular cancer with minimal invasiveness and surgical complications. Patients in our studies experienced excellent local tumor control. With the availability of indigenous ‘BARC I-125 Ocu-Prosta seeds’ locally, cost effective ophthalmic brachytherapy can be performed in India.


Subject(s)
Brachytherapy/instrumentation , Brachytherapy/methods , Choroid Neoplasms/radiotherapy , Choroid Neoplasms/therapy , Humans , India , Iodine Radioisotopes/administration & dosage , Models, Biological , Ophthalmologic Surgical Procedures/methods , Prostheses and Implants
19.
Chinese Journal of Experimental Ophthalmology ; (12): 692-698, 2012.
Article in Chinese | WPRIM | ID: wpr-635870

ABSTRACT

Background Choroidal melanoma (CM)is the most common primary intraocular tumor,and brachytherapy is one of the most common therapeutic modality in the treatment of the tumor.However,this irradiation approach has not been evaluated in China. Objective The present study was to analyze the effectiveness and safety of domestic 125I plaque irradiation in the treatment of CM. Methods Forty New Zealand albino rabbits were randomized into 5 groups with 8 rabbits 8 eyes (right eyes) in each group.CM models were established in 16 of 40 New Zealand albino rabbits by implanting the rat B16F10 melanoma cell fragments into the suprachoroidal space of right eyes.After 3 weeks,domestic 125I plaque was fixed at the location of CM in the irradiation group 1,and 8 rabbits with CM served as model control group.The clinical effectiveness of 125I plaque for CM was evaluated based on the fundus examination with indirect ophthalmoscopy,B scan ultrasonography,fundus photographs and color Dopplerimaging.Regarding the safety study,domestic 125I plaque was fixed on the normal right cycs of normal rabbits,while the plaques without 125I seeds were used as the sham group.No intervene was performed in the rabbits of blank group.The number of CD4+,CD8+ T cells in peripheral blood was detected by flow cytometry before plaques implanted and on 3,7,15 and 30 days after the plaque was removed.The animals were sacrificed and the eyes were obtained for histology examination.The use of the experimental animals complied with Statement of ARVO. Results After implantation of B16F10 melanoma cell fragments,CM grew steadily and rapidly with the similar size between irradiation group 1 and model control group ( P =0.550).One week after administration of the treatment,tumor size was(0.31±0.07 )cm in irradiation group 1 and (0.85±0.18 )em in the model control group,with the significant difference between them( P=0.001 ).Two week after application of 125I plaque,the size of tumor was smaller than that before irradiation (P=0.007 ).Histologically,the tumors were mostly limited beneath the pigment epithelial layer with less neovascularization,fibrosis in the tumor was found in some area in the irradiation group when compared with model control group.No significant differences were found in the proportions of CD4+,CD8+ T cells and CD4+/CD8+ at different time points in the irradiation groups of normal eyes and sham group (Fgroup =0.770,8.110,2.230; P=0.380,0.060,0.140; Ftime =0.770,3.220,4.230; P =0.550,0.170,0.004 ).Chronic inflammatory cells infiltration cornea,subconjunctival epithelial and selera surface,but sclera had no necrosis and organization.Conclusions These results suggest that domestic 125I plaque irradiation is effective for the treatment of CM,and has limited side effects on normal rabbits.

20.
Chinese Journal of Experimental Ophthalmology ; (12): 598-602, 2012.
Article in Chinese | WPRIM | ID: wpr-635840

ABSTRACT

Background Angiogenesis is an essential event for the growth and mobility of malignant tumors,but there is little literature about the effects of anoxia and angiogenesis-related factors on angiogenesis in choroidal melanoma.Objective The aim of this study was to investigate the expression of angiogeneic factors such as hypoxia inducible factor-1α(HIF-1α),inducible nitric oxide synthase(iNOS),cyclooxygenase-2(COX-2),and vascular endothelial growth factor(VEGF)in choroidal melanoma and their clinical significance.Methods The specimens from 44 cases of choroidal melanoma and 16 cases of eyelid nevi identified by pathology were collected.Immunohistochemistry SP was used to examine the expression of HIF-1α,iNOS,COX-2 and VEGF in the samples.The expression of HIF-1 α,iNOS,COX-2 and VEGF in tumors with different sizes,different pathological types and different growth patterns was evaluated.The correlations among these four proteins in tumor growth and development were assessed.Results The expression of HIF-1α,iNOS,COX-2 and VEGF in choroidal melanoma were significantly higher than those in the eyelid nevi group(x2 =6.58,4.105,8.350,13.240,P<0.05).The expression of VEGF was associated with tumor size(x2 =9.389,P<0.05),but not associated with pathological types(x2 =1.186,P>0.05)and infiltration depth(x2 =5.398,P> 0.05).The expression of HIF-1α was associated with tumor size(x2=8.664,P<0.05)and pathological type(x2=6.622,P < 0.05),but not associated with infiltration depth(x2=4.914,P>0.05).The expression of iNOS was associated with tumor size(x2 =8.609,P<0.05),but was not associated withpathological type(x2 =4.789,P>0.05)and infiltration depth(x2 =4.309,P>0.05).The expression of COX-2 was associated with tumor size(x2 =7.320,P<0.05),but was not associated with pathological type(x2 =2.772,P>0.05)and infiltration depth(x2 =2.103,P>0.05).The expression of HIF-1 α,iNOS,and COX-2 were significantly correlated with the expression of VEGF(r =0.943,1.000,0.986,P < 0.05).The expression of COX-2 was significantly correlated with the expression of iNOS(r =0.986,P<0.05).The expression of HIF-1 α was significantly associated with the expression of COX-2(r=0.986,P<O.05).The expression of HIF-1α was significantly associated with the expression of iNOS(r=0.943,P<0.05).Conclusions The expressions of the HIF-1 α,iNOS,COX-2 and VEGF protein are up-regulated in choroidal melanoma.They may play important roles in the angiogenesis of the choroidal melanoma.Assessment of the expression of HIF-1α,iNOS and COX-2 may be useful for the diagnosis and therapy of choroidal melanoma.

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