Amorphous silicon (a-Si) electronic portal imaging devices (EPIDs) are x-ray detectors frequently used in radiotherapy imaging and dosimetry applications. EPIDs employ a copper plate and gadolinium oxysulfide phosphor screen with an array of a-Si photodiodes to indirectly detect incident radiation. In this study, a previously developed Monte Carlo (MC) model of an aSi EPID has been extended for...

Respiratory gating based on external surrogates is performed in many clinics. We have developed a new technique for treatment verification using an electronic portal imaging device (EPID) in cine mode for gated 3D conformal therapy. Implanted radiopaque fiducial markers inside or near the target are required for this technique. The markers are contoured on the planning CT set, enabling us to cr...

Telah dilakukan penelitian mengenai verifikasi pergesesaran geometri pada pesawat Linear Accelerator (Linac) tipe Clinax CX menggunakan Electronic Portal Imaging Device (EPID). Verifikasi 10 data rekam medis pasien kanker nasofaring di Instalasi Radioterapi Rumah Sakit Universitas Andalas. Proses diawali dengan perencanaan Treatment Planning System (TPS) Software Eclipse dilanjutkan penyinaran ...

BACKGROUND The reproducibility of patient setup for radiotherapy is based on various methods including external markers, X-rays with planar or computerized image acquisition, and, more recently, surface matching imaging. We analyzed the setup reproducibility of 16 patients affected by prostate cancer who underwent conformal radiotherapy with curative intent by using a surface image registration...

BACKGROUND This study retrospectively compared the continuous epidural infusion of morphine with a single epidural injection of extended-release morphine for postoperative pain control after arthroplasty. METHODS Medical records were reviewed for subjects who had total knee or hip arthroplasty (THA) under spinal anesthesia and received either a continuous epidural infusion of morphine (Group ...

Recently, with the advent of linear accelerators equipped with on-board x-ray images and advanced imaging technologies, image-guided radiotherapy (IGRT) has gained worldwide momentum in the radio therapeutic management of cancers in terms of volumetric information-based accurate tumor localization, real-time patient setup and margin reduction [1,2]. The involved technologies include digital rad...

This paper presents a bio-inspired method for in-vivo control of blood glucose based on a model of the pancreatic β-cell. The proposed model is shown to be implementable using low-power analogue integrated circuits in CMOS, realizing a biologically faithful implementation which captures all the behaviours seen in physiology. This is then shown to be capable of glucose control using an in silico...

A study was performed to determine the relative advantage of computer-controlled couch movement versus manual repositioning to correct patient setup error measured using an electronic portal imaging device (EPID). Twenty-eight on-line setup adjustment trials of anterior-posterior (AP) pelvic projections were evaluated, with 13 setups corrected by automated couch movement determined by direct fe...

Correlated responses in whole-body composition were determined in 12-wk-old male mice from replicate lines selected for 12 generations for high (HF) or low (LF) epididymal fat pad weight as a percentage of body weight (EPID) and high (HL) or low (LL) hind carcass weight as a percentage of body weight. The HF and LF lines diverged (P less than .01) in body fat percentage (FAT) and subcutaneous d...

This study compares the EPID dosimetry algorithms of two commercial systems for pretreatment QA, and analyzes dosimetric measurements made with each system alongside the results obtained with a standard diode array. 126 IMRT fields are examined with both EPID dosimetry systems (EPIDose by Sun Nuclear Corporation, Melbourne FL, and Portal Dosimetry by Varian Medical Systems, Palo Alto CA) and th...