Sleep disorders affect a great percentage of the population. The diagnostic these is usually made by polysomnography, requiring patient’s hospitalization. Low cost ambulatory devices can in certain cases be used, especially when there no need full or rigorous sleep staging. In this paper, several methods to extract features from 6 EEG channels are described order evaluate their performance. selected using R-square Pearson correlation coefficient (Guyon and Elisseeff, 2003), providing way...

Precise monitoring of the particle range inside body, preferably in real-time, is a primary interest quality assurance therapy. Prompt-gamma (PG) detection aims at this task, but such system technically challenging to implement. For mechanically collimated PG detection, neutron-induced background radiation originating collimator material major issue. We study by Monte-Carlo simulations (Geant4), influence different designs and their geometric parameters - as distance source, size septa...

Prompt-gamma (PG) imaging has the potential for monitoring proton therapy in real time. Different approaches are investigated. We focus on developing multi-slat collimators to image PG quanta, aiming at optimizing collimator performance detect deviations treatment delivery. investigated six different configurations, which have either optimal (analytical) intrinsic spatial resolution fixed efficiency, or otherwise; distances from pencil-beam axis (15 cm–35 cm). used Geant4 simulate...

Orthogonal ray imaging is a new technique under investigation by our groups. It shows good potential for (1) dose verification in external beam radiotherapy and (2) very-low-dose computed tomography (CT-like) imaging. We have simulated with Geant4 the performance of four flat-panel-like perfect detectors evaluating capabilities orthogonal portal assisting therapy. The were positioned surrounding head patient, three parallel one perpendicular to axis. Each detector covers an area 185 mm ×...

Radiotherapy (RT) is nowadays, after surgery the most frequently used treatment of cancer. For predicted clinical outcomes it importance assuring that plan correctly delivered without dose deviations, namely target underdosage and/or organ-at-risk overdosage. that, a new multipixel imaging technique for real-time verification during photon RT has been proposed (RTmon). The principle operation RTmon relies on detection scattered photons emitted perpendicularly to beam direction. First...

Orthogonal ray imaging is a new technique under investigation by our groups. It shows good potential for (1) dose verification in external beam radiotherapy, and (2) very-low-dose computed tomography (CT-like) imaging, the latter being investigated here. We present simulated (Geant4) experimental orthogonal results of visualization heterogeneous phantom irradiated from both sides with 6-MV photon beam. The was constructed azimuthal symmetry respect to incoming directions. This technique,...

An out-of-yoke irradiation setup using the proton beam from a cyclotron that ordinary produces radioisotopes for positron emission tomography (PET) has been developed, characterized, calibrated and validated. The current 20 μm thick aluminum transmission foil is readout by home-made transimpedance electronics, providing online dose information. main monitoring variables, delivered in real-time, include current, integrated charge rate. Hence at given instant to an experimental can be...

A new imaging technique, called orthogonal ray imaging, has been proposed to assist external-beam radiation therapy treatments. This technique consists in detecting scattered the patient and emitted perpendicularly incident beam axis. Since photon scattering occurs with higher intensity tissues of density, a detection system (constituted by multi-slice collimator detector) positioned axis yields signal proportional photons that escaped (i.e., correlated morphology). Unlike some other...

Modern radiotherapy (RT) techniques provide increasingly higher conformality, a potential invaluable clinical benefit to the patient. Consequently, in both single and multi-fractionated RT, patient misalignments changing internal anatomy are also becoming more critical since conformality may equally represent risk of target underdosage or organ-at-risk overdosage. Even with rigid fixation devices, maximum positioning errors than 1 cm observable. In addition, anatomical morphological...

Different cyclotron models capable of accelerating protons up to 20MeV have been worldwide installed. Although their purpose is mainly positron emission tomography (PET) radioisotope production, they are equipped with several beam lines suitable for scientific research. Each line may typically deliver proton currents 150 μA (1×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sup> particles/s). Radiobiological and dosimetric studies can be...

Transcranial magnetic stimulation (TMS) was proposed in 1985. Nevertheless, its wider use the treatment of several neurologic diseases has been hindered by inability to stimulate deep-brain regions. This is mainly due physical limiting effect arising from presence surface discontinuities, particularly between scalp and air. Here, we present optimization a system large multiple coils for whole-brain half-hemisphere deep TMS, termed orthogonal configuration. COMSOL <sup...

The number of cyclotrons capable accelerating protons to about 20 MeV is increasing throughout the world. Originally aiming at production positron emission tomography (PET) radionuclides, some these facilities are equipped with several beam lines suitable for scientific research. Radiobiology, radiophysiology, and other dosimetric studies can be performed using lines. In this work, we measured Bragg peak from a PET cyclotron stacked target consisting aluminum foils interleaved polyethylene...

We analyze by simulation a fully-3-D, low-dose imaging system aiming at assisting external-beam radiotherapy, either for on-board patient imaging, or real-time radiotherapy monitoring. The consists in detecting megavoltage patient-scattered radiation that is emitted right angles with respect to the beam axis. Since photon scattering occurs higher intensity tissues of density, multislice detection positioned perpendicularly axis yields signal correlated morphology, including tumor. thus...

The OrthoCT (standing for orthogonal computed tomography) imaging technique consists in detecting radiation scattered the patient and emitted at right angles with respect to incident beam axis. Since photon scattering occurs higher intensity tissues of density, a detection system (constituted by multi-slice collimator detector) positioned perpendicularly axis yields signal proportional photons that escaped (i.e., correlated morphology). This low-dose morphological can potentially be useful...

A new very-low-dose imaging technology to assist external-beam radiotherapy treatments has been proposed. This technique, called orthogonal ray imaging, does not require X-ray source rotation around the target. It is based on detection of photons escaping target at almost right angles with respect incoming photon flux. Modern image-guided radiation therapy techniques allow an accurate positioning patient, consequently improving treatment accuracy. However, some these techniques, such as...

Radiotherapy (RT) is nowadays, after surgery, among the most commonly used treatment regarding cancer. For predicted clinical outcomes it of importance assuring that plan correctly delivered without dose deviations, namely target underdosage and/or organ-at-risk overdosage. that, a new multi-pixel imaging technique for real-time verification during photon RT has been proposed (RTmon). First scanned, single-pixel experimental results are presented here. The principle operation RTmon relies on...

The number of cyclotrons capable accelerating protons to about 20 MeV is increasing throughout the world. In Portugal, an IBA (Ion Beam Applications, Belgium) model Cyclone 18/9 cyclotron was installed at ICNAS (Instituto de Ciencias Nucleares Aplicadas a Saude) for positron emission tomography (PET) in 2010. Such facility equipped with eight beam lines suitable scientific research. Each line may deliver proton currents up 150 μA (1×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...

OrthoCT (orthogonal computed tomography) is a potential new imaging technique that aims to acquire images of the volume be irradiated immediately before or during radiotherapy treatment. It potentially provides with very low eventually null dose, allowing check if morphology/anatomy patient and tumour are in agreement planned one. This relies on detection photons scattered emitted perpendicularly incident beam direction. To morphological scanning done using pencil-like mega-voltage beams....

The full potentialities of deep-brain transcranial magnetic stimulation (TMS) are presently limited by the so-called surface discontinuity effect. This effect is responsible for a strong reduction capability TMS systems to reach satisfactorily regions with biostimulatory and/or bioinhibitory purposes. Consequently, large number neuropathologies that could potentially profit from remain either unknown, or yield clinical trials inconclusive results. Previous simulation studies have pointed...

The orthogonal computed tomography (OrthoCT) concept, based on ray imaging, is a low-dose imaging technique currently under investigation to potentially aid in external-beam radiation therapy treatments. This involves detecting scattered within the patient and emitted at approximately 90&amp;deg; from direction of incoming beam. can be collected by 1D-detector system with multisliced collimator positioned perpendicular incident beam axis. Such holds promise for on-board prepared treatment,...

. Bragg peak measurements play a key role in the beam quality assurance proton therapy. Used as base data for treatment planning softwares, accuracy of is crucial when defining range protons patient.

Orthogonal ray imaging is a new low-dose technology under study aimed at assist externalbeam radiotherapy (EBRT) treatments.It consists in detecting radiation scattered the patient and emitted perpendicularly to incident beam.Such can be collected by positioning multi-sliced, collimator-based, 1D detector system parallel beam axis, hence collecting such orthogonal rays, or using pinhole-like positioned above below patient.This potentially useful for on-board imaging, real-time EBRT...