Telecobalt machine is one of the essential equipment needed in many cancer centers and still prominently used for the treatment of a variety of cancer cases in developing countries. This study aims to evaluate the impact of tissue heterogeneity corrections on 3D treatment planning system (Prowess). The human body contains a variety of tissues and cavities which vary widely in their physical and...

Introduction Use of nonselective refocusing pulses shortens the echo spacing and the echo train duration, and then improves the image sharpness in SPACE [3, 4] imaging. However, the nonselective refocusing pulses limit the application of slab selective acquisition. To overcome this limitation, a dual echo-spacing technique [1] has been presented before, using a combination of selective excitati...

background: prediction of the absorbed dose in irradiated volume plays an important role in the outcome of radiotherapy. application of small fields for radiotherapy of thorax makes the dose calculation process inaccurate due to the existence of electronic disequilibrium and intrinsic deficiencies in dose calculation algorithms. to study the lung absorbed dose in radiotherapy with small fields,...

for superficial lesions, the electrons may be used for radiation therapy. the high energy photons and electrons are produced by a linear accelerator (linac).   many of electron fields need the shielding of normal or critical organs. the electron shields are usually lead slabs with few millimeter thickness which should be placed near the skin, less than 1 centimeter away from skin. in the inspec...

Near-infrared spectroscopy (NIRS) estimations of the adult brain baseline optical properties based on a homogeneous model of the head are known to introduce significant contamination from extracerebral layers. More complex models have been proposed and occasionally applied to in vivo data, but their performances have never been characterized on realistic head structures. Here we implement a fle...

In this study, a new approach to high-speed fMRI using multi-slab echo-volumar imaging (EVI) is developed that minimizes geometrical image distortion and spatial blurring, and enables nonaliased sampling of physiological signal fluctuation to increase BOLD sensitivity compared to conventional echo-planar imaging (EPI). Real-time fMRI using whole brain 4-slab EVI with 286 ms temporal resolution ...