Microdosimetric single event spectra as a function of depth in a phantom for the 290 MeV/nucleon therapeutic carbon beam at HIMAC were measured by using a tissue equivalent proportional counter (TEPC). Two types of geometries were used: one is a fragment particle identification measurement (PID-mode) with time of flight (TOF) method without a backward phantom, and the other is an in-phantom mea...

This study investigates the influence of several Monte Carlo radiation transport codes and nuclear models on simulation secondary neutron spectra its impact calculating measuring doses in proton therapy. Three different multi-purpose (FLUKA, MCNPX, Geant4) were used with available to calculate energy at various points inside a water tank phantom PMMA walls using 10 cm x rectangular, mono-energe...

Multi-slat prompt-gamma camera is a promising tool for range monitoring during proton therapy. We report the results of comprehensive simulation study analyzing precision which possible to reach with this in determination position distal edge Bragg peak. For first time we include optical photons. The beam (single pencil beam, 130 MeV, 10 ns bunch period, total 1·108 protons) interacting polymet...

Intensity modulated proton therapy (IMPT) implies the electromagnetic spatial control of well-circumscribed "pencil beams" of protons of variable energy and intensity. Proton pencil beams take advantage of the charged-particle Bragg peak-the characteristic peak of dose at the end of range-combined with the modulation of pencil beam variables to create target-local modulations in dose that achie...

PURPOSE To investigate the variations in induction and repair of DNA damage along the proton path, after a previous report on the increasing biological effectiveness along clinically modulated 60-MeV proton beams. METHODS AND MATERIALS Human skin fibroblast (AG01522) cells were irradiated along a monoenergetic and a modulated spread-out Bragg peak (SOBP) proton beam used for treating ocular m...

PURPOSE To investigate the clinical implications of a variable relative biological effectiveness (RBE) on proton dose fractionation. Using acute exposures, the current clinical adoption of a generic, constant cell killing RBE has been shown to underestimate the effect of the sharp increase in linear energy transfer (LET) in the distal regions of the spread-out Bragg peak (SOBP). However, experi...

purpose: to evaluate of proton therapy (pt) for neurosurgery patients and is also to explain the need for this system in iran. methods: a literature review was conducted (1984–2016). the strategy included a combination of keywords including proton therapy, neck, neurosurgery, brain, head, tumor, spine, arteriovenous malformation (avms), cervical and spine in database of pubmed. new generation p...

Fig 1: Comparison of the depth dose profiles of proton and photon beams. The photon dose falls off exponentially with depth (green curve). A mono-energetic proton beam is characteriled by the presence of the Bragg peak in the region where the protons stop (red profile). Through the superposition (blue curve) of many proton beams of different residual range it is possible to deposit a homogenous...

In comparison to conventional photon therapy heavy-ion beams offer favourable conditions for the treatment of deep-seated local tumors. The physical depth-dose distribution in tissue is characterized by a small entrance dose and a distinct maximum (Bragg peak) near the end of range with a sharp fall-off at the distal edge. The well-defined range and the small lateral beam spread make it possibl...