%0 Journal Article
%T Novel low-kVp beamlet system for choroidal melanoma
%A Carlos Esquivel
%A Clifton D Fuller
%A Robert G Waggener
%A Adrian Wong
%A Martin Meltz
%A Melissa Blough
%A Tony Y Eng
%A Charles R Thomas
%J Radiation Oncology
%D 2006
%I BioMed Central
%R 10.1186/1748-717x-1-36
%X Monte Carlo N-Particle (MCNP) transport code version 5.0(14) was used to simulate photon interaction with normal and tumor tissues within modeled right eye phantoms. Five modeled dome-shaped tumors with a diameter and apical height of 8 mm and 6 mm, respectively, were simulated distinct positions with respect to the macula iteratively. A single fixed 9 ¡Á 9 mm2 beamlet, and a comparison COMS protocol plaque containing eight I-125 seeds (apparent activity of 8 mCi) placed on the scleral surface of the eye adjacent to the tumor, were utilized to determine dosimetric parameters at tumor and adjacent tissues. After MCNP simulation, comparison of dose distribution at each of the 5 tumor positions for each modality (BLOKX vs. eye-plaque) was performed.Tumor-base doses ranged from 87.1¨C102.8 Gy for the BLOKX procedure, and from 335.3¨C338.6 Gy for the eye-plaque procedure. A reduction of dose of at least 69% to tumor base was noted when using the BLOKX. The BLOKX technique showed a significant reduction of dose, 89.8%, to the macula compared to the episcleral plaque. A minimum 71.0 % decrease in dose to the optic nerve occurred when the BLOKX was used.The BLOKX technique allows more favorable dose distribution in comparison to standard COMS brachytherapy, as simulated using a Monte Carlo iterative mathematical modeling. Future series to determine clinical utility of such an approach are warranted.Choroidal melanoma is the most common intraocular malignancy in adults, originating within the pigmented cells of the choroid [1]. Management of patients with this neoplasm is complex and remains the subject of much discussion. The treatment modality of choice is predicated in part by the size and location of the tumor [2,3].Until the 1980's, the standard treatment of choroidal melanoma was the removal of the eye by enucleation [4]. Alternative therapies have since been developed to preserve the eye and vision, such as laser photocoagulation, cryotherapy, local resection and radiati
%U http://www.ro-journal.com/content/1/1/36