effect of uniform magnetic field on dose distribution in the breast radiotherapy

نویسندگان

a.d. esmaeeli department of medical radiation engineering, science and research branch, islamic azad university, tehran, iran

m. pouladian department of medical radiation engineering, science and research branch, islamic azad university, tehran, iran

a.s. monfared department of medical physics, babol university of medical sciences, babol, iran

s.r. mahdavi department of medical physics, tehran university of medical sciences, tehran, iran

چکیده

background: to reduce the dose to normal tissues surrounding the treated breast, a uniform magnetic field was used within a humanoid phantom in breast radiotherapy. materials and methods: monte carlo simulations were performed with geant4, irradiating humanoid phantoms in a magnetic field. to reconstruct phantoms, computed tomography (ct) data slices of four patients were used for the monte carlo simulations. all of them had left breast cancer either or not mastectomy. in the simulations, the planning and methods of chest wall irradiation were similar to the actual clinical planning. results: utilizing magnetic field will help to produce uniform dose distribution to the breast with a sharp dose-volume histogram (dvh) curve for the planning target volume (ptv), however, for the ipsilateral lung and chest wall skin the mean dose was reduced by a mean of 16% and 12% at 1.5 t, and 9% and 7% at 3 t, respectively. the magnetic field was shown to restrict the lateral spread of secondary electrons to the contralateral organs, resulting in significient dose reductions to the contralateral breast (cb) and contralateral chest wall skin (ccws) by a mean (range) of 28% (21-37%) and 58% (44-75%) at 1.5 t, and 48% (32-81) and 66% (54-73%) at 3 t, respectively. conclusion: the simulations established that the magnetic field can reduce the dose to the internal and contralateral tissues and increase it to the ptv with sharper edge dvh curve.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effect of uniform magnetic field on dose distribution in the breast radiotherapy

Background: To reduce the dose to normal tissues surrounding the treated breast, a uniform magnetic field was used within a humanoid phantom in breast radiotherapy. Materials and Methods: Monte Carlo simulations were performed with GEANT4, irradiating humanoid phantoms in a magnetic field. To reconstruct phantoms, computed tomography (CT) data slices of four patients were used for the Monte Car...

متن کامل

The Effect of Breast Reconstruction Prosthesis on Photon Dose Distribution in Breast Cancer Radiotherapy

Introduction: Siliconeprosthetic implants are commonlyutilizedfor tissue replacement and breast augmentation after mastectomy. On the other hand, some patients require adjuvant radiotherapy in order to preventlocal-regional recurrence and increment ofthe overall survival. In case of recurrence, the radiation oncologist might have to irradiate the prosthesis.The aim of this study was to evaluate...

متن کامل

Electron Beam Dose Distribution in the Presence of Non-Uniform Magnetic Field

Introduction Magnetic fields are capable of altering the trajectory of electron beams andcan be used in radiation therapy.Theaim of this study was to produce regions with dose enhancement and reduction in the medium. Materials and Methods The NdFeB permanent magnets were arranged on the electron applicator in several configurations. Then, after the passage of the electron beams (9 and 15 MeV Va...

متن کامل

the washback effect of discretepoint vs. integrative tests on the retention of content in knowledge tests

در این پایان نامه تاثیر دو نوع تست جزیی نگر و کلی نگر بر به یادسپاری محتوا ارزیابی شده که نتایج نشان دهندهکارایی تستهای کلی نگر بیشتر از سایر آزمونها است

15 صفحه اول

electron beam dose distribution in the presence of non-uniform magnetic field

introduction magnetic fields are capable of altering the trajectory of electron beams andcan be used in radiation therapy.theaim of this study was to produce regions with dose enhancement and reduction in the medium. materials and methods the ndfeb permanent magnets were arranged on the electron applicator in several configurations. then, after the passage of the electron beams (9 and 15 mev va...

متن کامل

the effect of taftan pozzolan on the compressive strength of concrete in the environmental conditions of oman sea (chabahar port)

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
iranian journal of radiation research

جلد ۱۲، شماره ۲، صفحات ۱۵۱-۱۶۰

کلمات کلیدی

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023