introduction:  skin  sparing  is  one  of  the  most  desirable  characteristics  of  high  energy  photon  beams. however, the photons emerging from the target of linacs are contaminated by secondary  electrons  as  a  result  of  their  interactions  with  air,  collimators,  flattening  filter  and  any  other  objects in their path. this phenomenon tends to increase the skin dose received b...

PURPOSE To directly measure skin dose using point-dosimeters from dental cone-beam CT (CBCT) scans. To compare the results among three different dental CBCT scanners and compare the CBCT results with those from a conventional panoramic and cephalomic dental imaging system. METHODS A head anthropomorphic phantom was used with nanoDOT dosimeters attached to specified anatomic landmarks of selec...

INTRODUCTION A sweeping beam technique for total body irradiation in standard treatment rooms and for standard linear accelerators (linacs) is introduced, which does not require any accessory attached to the linac. Lung shielding is facilitated to reduce the risk of pulmonary toxicity. Additionally, the applicability of a commercial radiotherapy planning system (RTPS) is examined. MATERIAL AN...

Methods: The Optic Nerve (ON) coil was constructed using two fiberglass formers that fit together to surround the entire head. The anterior former supports 26 overlapping coil elements in a mask arrangement as shown in Fig. 1. The posterior former supports the neck and head and houses two additional overlapped coil elements, totaling to 28 elements. In this design, the two formers can slide ove...

Purpose: The experimental verification of the Acuros XB (AXB) algorithm was conducted in a heterogeneous rectangular slab phantom, and compared to the Anisotropic Analytical Algorithm (AAA). The dosimetric impact of the AXB for stereotactic body radiation therapy (SBRT) and RapidArc planning for 16 non-small-cell lung cancer (NSCLC) patients was assessed due to the dose recalculation from the A...

Neurofeedback- and brain-computer interface (BCI)-based interventions can be implemented using real-time analysis of magnetoencephalographic (MEG) recordings. Head movement during MEG recordings, however, can lead to inaccurate estimates of brain activity, reducing the efficacy of the intervention. Most real-time applications in MEG have utilized analyses that do not correct for head movement. ...

Although there are many works on evaluating dose calculations of the anisotropic analytical algorithm (AAA) using various homogeneous and heterogeneous phantoms, related work concerning dosimetry due to tangential photon beam is lacking. In this study, dosimetry predicted by the AAA and collapsed cone convolution (CCC) algorithm was evaluated using the tangential photon beam and phantom geometr...

The performance of a cellular phone commercial helical antenna at 900 MHz band, both in free space and in the presence of a human head phantom was studied. Numerical simulation of the phone model for the latter case has been performed giving 3D radiation diagrams. The effect of the phantom head on radiation diagrams is presented. The relative amount of the EM power absorbed in the head was obta...

OBJECTIVE To evaluate three-dimensional translational setup errors and residual errors in image-guided radiosurgery, comparing frameless and frame-based techniques, using an anthropomorphic phantom. MATERIALS AND METHODS We initially used specific phantoms for the calibration and quality control of the image-guided system. For the hidden target test, we used an Alderson Radiation Therapy (ART...

BACKGROUND Electroencephalography (EEG) can capture the cortical response evoked by transcranial magnetic stimulation (TMS). The TMS pulse provokes a large artefact, which obscures the cortical response in the first milliseconds after TMS. Removing this artefact remains a challenge. METHODS We delivered monophasic and biphasic TMS to a melon as head phantom and to four healthy participants an...