Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
1.
Healthc Policy ; 19(3): 33-41, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38721732

RESUMO

This paper examines the contentious issue of using contracted surgical facilities (CSFs) for scheduled eye surgeries within Canada's publicly funded healthcare system. Despite the debate over the use of CSFs, there is a stark lack of Canadian-focused empirical evidence to guide policy decisions. This paper uses the Organisation for Economic Co-operation and Development's healthcare system performance conceptual model - access, quality and cost/expenditures - as a framework to explore the debates surrounding CSFs. It highlights the mixed evidence from international studies and proposes recommendations for policy makers to ensure equitable access, maintain high-quality care and achieve cost-effectiveness. The paper underscores the necessity for informed policy making supported by robust empirical research, stakeholder engagement and continuous policy evaluation to address the challenges posed by the integration of CSFs into Canada's healthcare landscape.


Assuntos
Acessibilidade aos Serviços de Saúde , Canadá , Humanos , Política de Saúde , Qualidade da Assistência à Saúde , Setor Privado , Procedimentos Cirúrgicos Oftalmológicos
2.
Am J Ophthalmol ; 262: 161-169, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38307213

RESUMO

PURPOSE: To determine the incidence and type of strabismus in patients with uveal melanoma treated with plaque brachytherapy. DESIGN: Multicenter, retrospective incidence estimation study. METHODS: A total of 438 eyes of 438 patients with uveal melanoma treated with plaque brachytherapy between October 2011 and May 2021. Intervention was Iodine 125, and Palladium 103 plaque brachytherapy. The variables reviewed included incidence of nonresolving strabismus post-plaque brachytherapy, type of strabismus developed, extraocular muscles operated, and modality of treatment received. RESULTS: A total of 438 patients underwent plaque brachytherapy treatment for uveal melanoma. Eleven patients developed strabismus post-plaque brachytherapy (2.5%, n = 11/438). Of these patients, 5 (1.1%, n = 5/438) developed strabismus immediately postoperation. Specifically, 2 patients (0.5%, n = 2/438) developed strabismus immediately postoperation due to slipped muscles, 2 patients (0.5%, n = 2/438) due to decompensated phorias, and 1 patient (0.5%, n = 1/438) due to a fibrotic muscle. Six patients (1.4%, n = 6/438) developed late-onset sensory strabismus. A total of 355 patients (81.1%, n = 355/438) had their extraocular muscles disinserted during surgery, with the lateral rectus being the most common, accounting for 45.4% (n = 161/355), followed by the superior rectus at 26.8% (n = 95/355). Strabismus surgery was the most common treatment modality, comprising 72.7% (n = 8/11) of patients. CONCLUSIONS: The incidence of strabismus after plaque brachytherapy treatment for uveal melanoma was low and primarily classified as late-onset sensory strabismus. Previous studies may underestimate the long-term incidence of strabismus after plaque brachytherapy by focusing primarily on strabismus present immediately postoperatively.

3.
Ophthalmic Plast Reconstr Surg ; 40(1): 11-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37486339

RESUMO

PURPOSE: There is no known optimal treatment for primary periocular orofacial granulomatosis (PPOFG), a disorder that results in periocular edema. This case series and systematic review identifies management strategies and their reported improvement. METHODS: Systematic review and case series. PubMed and MEDLINE databases were searched following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines to identify published cases of PPOFG. Cases were included when edema involved the periocular tissues and when a biopsy was interpreted to be PPOFG. Cases were excluded when edema did not involve the periocular tissues or when the edema was secondary to another process. The electronic medical records of the pathology department were studied to identify cases that were in keeping with PPOFG. The clinical charts were examined to confirm the diagnosis and provide a local case series. RESULTS: There are 38 published cases of PPOFG. An additional 9 cases were identified locally. These cases were combined and analyzed. Most PPOFG has eyelid swelling in isolation, without other facial swelling (36/47; 76.6%). It is most commonly a bilateral disease (30/47; 63.8%). Fissured tongue and facial nerve palsy occur, just as they do in other cases of orofacial granulomatosis. Treatment with surgical debulking or intralesional steroids resulted in high rates of symptomatic improvement of eyelid swelling, but recurrences were common. CONCLUSIONS: In light of no curative or highly successful treatment currently available, intralesional steroids and/or surgical debulking are therapies in the treatment of eyelid swelling associated with PPOFG that demonstrate reasonable short- and medium-term results. There is no established therapy that can offer disease remission or long-term symptom improvement.


Assuntos
Paralisia Facial , Granulomatose Orofacial , Humanos , Granulomatose Orofacial/terapia , Granulomatose Orofacial/tratamento farmacológico , Edema/diagnóstico , Biópsia , Esteroides/uso terapêutico
4.
Cancers (Basel) ; 15(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37627170

RESUMO

The objective of this study was to evaluate the psychometric properties of a new patient-reported outcome instrument intended for use with patients who have undergone brachytherapy for uveal melanoma (PROM-UM). Classical test theory and item response theory were used to evaluate the performance of individual items and domains. A convenience sample of 439 participants who had undergone brachytherapy for uveal melanoma from one of three North American ocular oncology treatment centers were included in this cross-sectional study. Exploratory factor analysis identified three domains which were labelled "Symptom Impairment", "Worry", and "Discomfort". The acceptability of the instrument was supported by little missing data (range = 0.00-1.14%) and low maximum endorsement (range = 0.00-1.82%). Item-total (range = 0.68-0.85) and inter-item (range = 0.74-0.80) correlations indicated acceptable reliability. Discrimination and difficulty were assessed using item response theory. Items in all three domains indicated moderate to very high discrimination (range = 1.00-4.10). Two items in the Symptom Impairment domain were too difficult to measure. Response ranges in the other two domains demonstrated acceptable difficulty. These results from the study indicate that this new patient-reported outcome instrument can be used with patients treated with brachytherapy for uveal melanoma. Providers could use this instrument to help inform post-treatment management.

6.
Ocul Oncol Pathol ; 8(4-6): 230-235, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36925730

RESUMO

Introduction: Radiation retinopathy is a dose-dependent complication of the retina following exposure to ionizing radiation. The objective of this prospective case series is to determine the clinical efficacy of intravitreal aflibercept for radiation retinopathy secondary to radiotherapy for uveal melanoma in those that failed intravitreal bevacizumab treatment. Methods: A case series of 30 patients with a mean age of 57 ± 15 years with radiation retinopathy were enrolled. Visual acuity (VA) and central foveal thickness (CFT) responses to therapy were assessed with regression analyses at 1 month, 3 months, and 6 months following the switch to aflibercept. Results: Regression analyses showed a statistically significant reduction in CFT and improvements in VA following the switch to treatment by aflibercept at 1 month, 3 months, and 6 months. The mean CFT improved from 476 µm ± 170 to 386 µm ± 139 and the mean VA improved minimally from 20/115 ± 20/63 to 20/112 ± 20/54 over 6 months. After 6 months of aflibercept, 46% of patients displayed a CFT improvement of 100 µm or greater and 23% of patients showed improvement in VA of 1 line or better. Conclusion: This pilot study suggests that patients with radiation retinopathy who have failed monthly intravitreal bevacizumab may respond to aflibercept.

7.
Curr Oncol ; 31(1): 24-41, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275828

RESUMO

OBJECTIVE: The purpose of this guideline update is to reassess and update recommendations in the prior guideline from 2016 on the appropriate management of patients with uveal melanoma. METHODS: In 2021, a multidisciplinary working group from the Provincial Cutaneous Tumour Team, Cancer Care Alberta, Alberta Health Services was convened to update the guideline. A comprehensive review of new research evidence in PubMed as well as new clinical practice guidelines from prominent oncology groups informed the update. An enhancement in methodology included adding levels of evidence and strength of recommendations. The updated guideline was circulated to all members of the Provincial Cutaneous Tumour Team for review and endorsement. RESULTS: New and modified recommendations address provider training requirements, diagnostic imaging for the detection of metastases, neo-adjuvant pre-enucleation radiotherapy, intravitreal anti-vascular endothelial growth factor agents for radiation retinopathy, genetic prognostic testing, surveillance following definitive local therapy, and systemic therapy for patients with metastatic uveal melanoma. DISCUSSION: The recommendations represent evidence-based standards of care agreed to by a large multidisciplinary group of healthcare professionals.


Assuntos
Melanoma , Neoplasias Cutâneas , Neoplasias Uveais , Humanos , Alberta , Melanoma/diagnóstico , Melanoma/terapia , Melanoma/patologia , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/terapia , Neoplasias Uveais/patologia
8.
Can J Ophthalmol ; 57(2): 105-111, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33839068

RESUMO

OBJECTIVE: Advancements in the treatment of uveal melanoma have not improved survival; therefore, identifying modifiable risk factors is critical to improving outcomes. This study aims to investigate the association between sunlamp use and the development of uveal melanoma. DESIGN: This study is designed as a meta-analysis. METHODS: Literature was searched and reviewed through the MEDLINE (with both OVID and PubMed), EMBASE, MD Consult, and Web of Science databases. These databases were searched from 1966 to 2019 using the following keywords to identify articles examining risk factors for uveal melanoma: ultraviolet, sun, sunlight, uveal melanoma, eye cancer, eye melanoma, nevus, and risk factor. All articles were evaluated for inclusion based on methodology and data reporting association between sunlamp use and uveal melanoma. The Meta-analysis of Observational Studies in Epidemiology guidelines and the Newcastle-Ottawa Scale were used to assess data quality and validity. A random effects model was employed. RESULTS: A total of 5 studies, enrolling a total of 1753 uveal melanoma cases and 3399 controls were included in this meta-analysis. The results of this study showed a positive association between sunlamp use and uveal melanoma (odds ratio = 2.15; 95% confidence interval 1.27-3.64). Meta-regression of between study heterogeneity did not reveal a statistically significant association when publication year, site latitude, melanoma tissue location (specifically, inclusion of iris tumors), or control type (population versus clinic) were evaluated. CONCLUSION: This meta-analysis identified a statistically significant association between sunlamp use and uveal melanoma, supporting sunlamp use as a modifiable risk factor for uveal melanoma.


Assuntos
Melanoma , Neoplasias Cutâneas , Neoplasias Uveais , Humanos , Melanoma/epidemiologia , Melanoma/etiologia , Fatores de Risco , Neoplasias Uveais/epidemiologia , Neoplasias Uveais/etiologia
9.
Br J Ophthalmol ; 106(5): 724-730, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33589435

RESUMO

BACKGROUND: Largest basal diameter (LBD) appears to have independent prognostic value in uveal melanoma (UM). METHODS: All patients undergoing plaque brachytherapy or enucleation for UM involving the choroid and/or ciliary body between 2012 and 2019. RESULTS: A total of 348 patients with a mean age of 60±14 years were included and followed for a mean of 40±26 months (3.3±2.2 years). On multivariate analysis, LBD >12 mm remained a significant independent predictor of metastasis for both class 1 (HR 21.90; 95% CI 2.69 to 178.02; p=0.004) and class 2 (HR 2.45; 95% CI, 1.03 to 5.83; p=0.04) tumours. Four prognostic groups were created: group 1 (class 1, LBD <12 mm), group 2 (class 1, LBD ≥12 mm), group 3 (class 2, LBD <12 mm) and group 4 (class 2, LBD ≥12 mm). Life tables were used to calculate the 3-year and 5-year metastasis-free survival: group 1 (98 and 98%), group 2 (86 and 86%), group 3 (81 and 62%) and group 4 (54 and 47%). Compared with the reference category (group 1), the Cox proportional hazard model demonstrated a significant worsening of survival for each progressive category (group 2 (HR 21.59; p=0.004), group 3 (HR 47.12, p<0.001), and group 4 (HR 114.24; p<0.001)). In our dataset, the four-category Cox model performed poorer compared with the American Joint Committee on Cancer (AJCC) and gene expression profile (AJCC+GEP) in the Akaike's information criteria (AIC) (297 vs 291), fit better with the Bayesian information criteria (BIC) (309 vs 313) and performed similarly with the Harrel's C (0.86 (95% CI 0.80 to 0.91) vs 0.89 (0.84 to 0.94), respectively). CONCLUSIONS: Combination of GEP and LBD allows separation of patients into four easy-to-use prognostic groups and was similar to a model combining AJCC stage with GEP.


Assuntos
Transcriptoma , Neoplasias Uveais , Idoso , Teorema de Bayes , Biópsia por Agulha Fina , Perfilação da Expressão Gênica , Humanos , Melanoma , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/genética , Neoplasias Uveais/radioterapia
10.
Arq Bras Oftalmol ; 85(2): 178-181, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34431900

RESUMO

Surgical management of large tumors involving the conjunctival fornix can be challenging, as exposure and clear margins may be difficult to achieve. In this case series, we report our initial experience with the open book technique in 4 patients. Through a canthotomy and cantholysis, this surgical approach provides a wide surgical field and facilitates fornix reconstruction post large tumor excision. In our series, one patient had a lateral canthus dehiscence.


Assuntos
Neoplasias da Túnica Conjuntiva , Aparelho Lacrimal , Túnica Conjuntiva/cirurgia , Neoplasias da Túnica Conjuntiva/cirurgia , Pálpebras/cirurgia , Humanos
11.
Digit J Ophthalmol ; 26(3): 27-30, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33867879

RESUMO

Uveal melanoma size is a significant predictor of tumor metastasis. Although the relationship between antivascular endothelial growth factors (VEGF) and uveal melanoma growth has been studied, results are paradoxical, and the relationship remains controversial. We report the case of a 65-year-old man who presented with elevated intraocular pressure in his right eye, neovascularization of his iris, and significant corneal edema, which obscured the view of the angle. Given his history of proliferative diabetic retinopathy, he was diagnosed with neovascular glaucoma and subsequently received an intravitreal injection of bevacizumab and underwent Ahmed valve insertion. This was complicated by postoperative hyphema. Two and a half months postoperatively, a mass involving the inferior iris and ciliary body became visible, and fine-needle aspiration biopsy confirmed uveal melanoma. Seven weeks after diagnosis, the tumor's largest basal diameter had increased from 2.51 mm to 18.0 mm, and apical height increased from 6.23 mm to 11.0 mm. His right eye was enucleated. Histopathological analysis showed discontinuous invasion next to the Ahmed valve. Tumor progression after injection raises the possibility that in some untreated uveal melanomas, accelerated growth may occur following exposure to anti-VEGF agents.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Bevacizumab/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Glaucoma Neovascular/tratamento farmacológico , Melanoma/patologia , Neoplasias Uveais/patologia , Idoso , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico por imagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Enucleação Ocular , Angiofluoresceinografia , Humanos , Pressão Intraocular , Injeções Intravítreas , Masculino , Melanoma/diagnóstico por imagem , Melanoma/etiologia , Microscopia Acústica , Neoplasias Uveais/diagnóstico por imagem , Neoplasias Uveais/etiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
12.
Brachytherapy ; 20(2): 433-445, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33431339

RESUMO

PURPOSE: The aim of this study was to develop an automated dose optimization algorithm, powered by simulated annealing, for inverse planning of ocular plaque brachytherapy treatments, to improve tumor coverage and critical structure sparing for reduced treatment-related morbidity. METHODS AND MATERIALS: A simulated annealing based algorithm was built and evaluated by finding variable seed strengths that maximized dose uniformity across tumor base for model cases of various tumor heights and plaque sizes. This problem assessed its potential to find the minima in the energy function using differential loading. The algorithm was further developed to decrease doses to critical structures while maintaining desired tumor coverage. Doses to the optic disc and fovea were compared to those using uniform seed strengths for various model cases. Finally, 10 retrospective patient cases treated with uniform seed strengths were replanned with the developed algorithm to evaluate effectiveness for clinical application. RESULTS: The developed algorithm achieved dose reductions of up to 37.3% and 39.6% to the optic disc and fovea, respectively, compared to those using uniform seed strengths, depending on the tumor and plaque size used for the model cases. Applying the algorithm to 10 clinical scenarios resulted in dose reductions of 14% to the optic disc and fovea relative to clinical treatments performed with uniform seed strengths. CONCLUSIONS: The developed automatic dose optimization routine was able to achieve significant dose reductions to the critical structures relative to using uniformly loaded plaques both in the model and in the clinical cases.


Assuntos
Braquiterapia , Neoplasias Oculares , Braquiterapia/métodos , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
13.
Ophthalmic Plast Reconstr Surg ; 37(3S): S23-S26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32675724

RESUMO

PURPOSE: A previously published predictive model based on threshold parameters for erythrocyte sedimentation rate, c-reactive protein, and platelet count demonstrated that 40% of patients who underwent biopsy may not have required it. The current study was performed to evaluate the model's performance on an independent data set. METHODS: This is a retrospective consecutive series of patients undergoing temporal artery biopsy (TAB) in a single health region in Canada. The model was applied to a multicenter cohort of patients undergoing TAB by a variety of surgical services. A centralized pathological database serving multiple institutions and surgical services was used to identify patients undergoing TAB. RESULTS: Over a 7-year period, patients undergoing TAB were identified via a central pathological database. Those who had concurrent illnesses which would likely affect erythrocyte sedimentation rate, c-reactive protein, and platelet count, patients on steroids for >2 weeks by the time of biopsy, and those with missing serum markers were excluded. The previously developed model was applied to the 222 patients enrolled. The model correctly identified 29% of patients with a pretest probability of 0% for a positive biopsy and 9% with a pretest probability of 100%, suggesting that in total, 38% of patients could have avoided TAB. CONCLUSION: The results of this independent data set support the previously published predictive formula. Utilizing a simple, clinically applicable predictive model of the pretest probabilities, approximately 38% of TAB currently being performed may be avoided. The results suggest that evaluation with a prospective multicentre study would be appropriate.


Assuntos
Arterite de Células Gigantes , Biópsia , Arterite de Células Gigantes/diagnóstico , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Artérias Temporais
15.
Eur J Ophthalmol ; 31(5): 2686-2691, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33008278

RESUMO

PURPOSE: To describe a standardized orbital resection technique and outcomes for spheno-orbital meningiomas with soft-tissue invasion of the orbit. METHODS: A retrospective case review of patients with spheno-orbital meningioma that underwent resection utilizing the Alberta Standardized Orbital Technique (ASOT) between 2008 and 2017 was performed. RESULTS: Twenty patients met the inclusion criteria. Fifteen females and five males, with an average age of 53.4 years (SD ± 13.1 years). Mean follow-up was 57.3 months (SD ± 29.5 months). Eight cases (40%) had attempted resection prior to referral. Based on pre-operative plan, patients were divided into two groups based on goal of resection. Of those with planned complete resection (Group I), 11/13 patients (84.6%) underwent complete excision, with no cases of orbital recurrence. Incomplete resection in two cases occurred because of unexpected involvement of critical intra-cranial structures. Thus, in total 9/20 patients (Group II and 2 from Group I) underwent subtotal resection. Of these incomplete resections, five cases of orbital recurrence were observed; four patients required adjuvant external beam radiotherapy (EBRT) and one patient underwent further debulking surgery. Orbital control was achieved in three of these recurrent cases. Complications reported were persistent postoperative diplopia (three cases/15%) and wound infection (one case/5%). Overall, stable orbital disease was obtained in 18 patients (90%). CONCLUSION: The ASOT demonstrated to be effective, achieving the pre-operative plan of complete resection in 11/13 cases (84.6%) with no recurrence in those with clear orbital margins.


Assuntos
Neoplasias Meníngeas , Meningioma , Neoplasias Orbitárias , Alberta , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Pessoa de Meia-Idade , Neoplasias Orbitárias/cirurgia , Estudos Retrospectivos , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/cirurgia , Resultado do Tratamento
16.
Ocul Oncol Pathol ; 6(5): 344-352, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33123528

RESUMO

Melanocytoma or hyperpigmented magnocellular nevus is a variant of melanocytic nevus that is most commonly seen in the optic nerve, but has also been reported to occur in the iris, ciliary body, choroid, sclera, and conjunctiva. We present two cases of giant uveal melanocytoma with histopathology. The first case occurred in a 10-year-old girl who presented with decreased vision in the right eye and a mushroom-shaped pigmented choroidal lesion measuring 15.5 mm in apical height. The lesion was abutting the lens but not causing a cataract. This was diagnosed as a choroidal melanocytoma on open scleral window biopsy. The second case was in a 68-year-old lady, referred for a left nasal pigmented choroidal lesion measuring 8 mm in apical height and having a mushroom configuration. The lesion grew to 8.6 mm in height and was complicated by a vitreous hemorrhage and rhegmatogenous retinal detachment and was treated with iodine-125 plaque brachytherapy. Subsequently, the treated eye became a painful phthisical eye and was enucleated. Histopathology confirmed melanocytoma with extrascleral extension but without malignant transformation. Features of melanocytoma and other very large cases reported in the literature are discussed.

18.
Ocul Oncol Pathol ; 5(4): 298-302, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31367594

RESUMO

BACKGROUND/AIMS: To evaluate teleophthalmological assessment of choroidal and iris nevi (tele-oncology) compared to traditional in-person clinical evaluation for detection of either axial or basal growth. METHODS: This is a validation study. All 97 eyes of 99 patients were evaluated with an in-person ocular oncology visit utilizing standard testing, and subsequently had a tele-oncology evaluation with the standardized tests. The tele-oncology reviewer was blinded to the in-person examination findings. The primary study outcome was detection of nevus growth on tele-oncology compared to in-person clinical examination. RESULTS: Patients had a mean age of 61 years and the majority had nevi located in the choroid (n = 87; 88%). The most common diagnosis was a low-risk nevus (n = 38; 44%). By tele-oncology assessment, 11 eyes showed growth. Ten of these patients had growth confirmed on in-person clinical examination. Resultantly, tele-oncology assessment of choroidal and iris nevi growth had a sensitivity of 100%, specificity of 99%, positive predictive value (PPV) of 91%, and negative predictive value (NPV) of 100%. CONCLUSIONS: The results of this study suggest that tele-oncology is a safe platform for monitoring choroidal and iris nevi for growth, with excellent sensitivity, specificity, PPV, and NPV.

19.
Brachytherapy ; 18(5): 668-674, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31272841

RESUMO

PURPOSE: The purpose of the study was to determine dosimetric effects of performing concurrent I-125 Collaborative Ocular Melanoma Study plaque brachytherapy and vitrectomy with replacement using silicone oil, previously shown to be a means of shielding uninvolved parts of the eye. METHODS AND MATERIALS: Monte Carlo simulations using MCNP6 were performed to compare the dosimetry with all eye materials assigned as water, and for the vitreous (excluding the tumor), composed of polydimethylsiloxane oil for three generic, one large tumor, and two patient geometry scenarios. Dose was scored at the tumor apex, along the sclera, and within a 3D grid encompassing the eye. The assessed patient cases included vitrectomies to treat intraocular pathologies; not to enhance attenuation/shielding. RESULTS: The doses along the sclera and for the entire eye were decreased when the silicone oil replaced the vitreal fluid, with a maximum decrease at the opposite sclera of 63%. Yet, absolute changes in dose to critical structures were often small and likely not clinically significant. The dose at the tumor apex was decreased by 3.1-9.4%. Dose was also decreased at the edges of the tumor because of decreased backscatter at the tumor-oil interface. CONCLUSIONS: Concurrent silicone vitrectomy was found to reduce total radiation dose to the eye. Based on current radiation retinopathy predictive models, the evaluation of the absolute doses revealed only a subset of patients in which a clinically significant difference in outcomes is expected. Furthermore, the presence of the silicone oil decreased dose to the tumor edges, indicating that the tumor could be underdosed if the oil is unaccounted for.


Assuntos
Braquiterapia/métodos , Neoplasias Oculares/radioterapia , Melanoma/radioterapia , Lesões por Radiação/prevenção & controle , Vitrectomia/métodos , Braquiterapia/efeitos adversos , Traumatismos Oculares/etiologia , Traumatismos Oculares/prevenção & controle , Humanos , Radioisótopos do Iodo/uso terapêutico , Método de Monte Carlo , Lesões por Radiação/etiologia , Protetores contra Radiação/uso terapêutico , Radiometria/métodos , Dosagem Radioterapêutica , Óleos de Silicone
20.
Cancers (Basel) ; 11(5)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137687

RESUMO

In contrast to the well-established association between ultraviolet radiation (UVR) exposure and skin cancers, the relationship between UVR and uveal malignant melanoma (UM) remains controversial. To address this controversy, we evaluated the incidence rates of cutaneous malignancies in the eyelids as a proxy for UVR exposure in the ocular region using a population-based cancer registry. Overall, 74,053 cases of eyelid basal cell carcinoma (BCC) and 7890 cases of melanoma over a 26-year period (1982-2007) were analyzed. The incidence of eyelid basal cell carcinoma and uveal melanoma remained stable, whereas other cutaneous areas demonstrated an increase in the rates. A comparability test demonstrated that BCC incidence trends were significantly different between the eyelid versus both chronically exposed (males p = 0.001; females p = 0.01) and intermittently exposed skin (males and females, p = 0.0002), as well as the skin of the face (males p = 0.002; females p = 0.02). Similarly, melanoma trends were significantly different between the UM group versus both chronically exposed cutaneous melanoma (CM) (males p = 0.001; females p = 0.04) and intermittently exposed CM (males p = 0.005), as well as facial skin CM (males and females p = 0.0002). The discrepancy of cancer incidence between tumors in the peri-ocular region versus the rest of the body suggests that the peri-ocular region might have a different or unique exposure pattern to ultraviolet radiation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA