Introduction: Use of SPECT/CT data is the most accurate method for patient-specific internal dosimetry when isotopes emit single gamma rays. The manual or semi-automatic segmentation of organs is a major obstacle that slows down and limits the patient-specific dosimetry. Using digital phantoms that mimic patient’s anatomy can bypass the segmentation step and facilitate the dosi...

PURPOSE MRI-based skull segmentation is a useful procedure for many imaging applications. This study describes a methodology for automatic segmentation of the complete skull from a single T1-weighted volume. METHODS The skull is estimated using a multi-atlas segmentation approach. Using a whole head computed tomography (CT) scan database, the skull in a new MRI volume is detected by nonrigid ...

Liver cancer is the sixth most common in world and fourth leading cause of mortality. In unresectable liver cancers, especially hepatocellular carcinoma (HCC), transarterial radioembolisation (TARE) can be considered for treatment. TARE treatment involves a contrast-enhanced magnetic resonance imaging (CE-MRI) exam performed beforehand to delineate tumour(s) order perform dosimetry calculation....

Traditionally rectal symptoms following pelvic/prostate radiotherapy are correlated to the dosimetry of the anorectum or a substructure of this. It has been suggested that the perirectal fat space (PRS) surrounding the rectum may also be relevant. This study considers the delineation and dosimetry of the PRS related to both rectal bleeding and control-related toxicity. Initially, a case-control...

Computed tomography (CT)/magnetic resonance imaging (MRI) fusion is considered to be the best method for postimplant dosimetry of permanent prostate brachytherapy; however, it is inconvenient and costly. In T2*-weighted image (T2*-WI), seeds can be easily detected without the use of an intravenous contrast material. We present a novel method for postimplant dosimetry using T2*-WI/T2-weighted im...

The aim of this report is to present a new two-piece thyroid-neck phantom produced by the concurrent use of epoxy resin and poly(methyl methacrylate) (PMMA: plexiglass) soft tissue equivalent materials. Accordingly, mass attenuation coefficients of the epoxy resin and the plexiglass compounds were obtained from simulation (NIST XCOM 3.1) and measurements (practical dosimetry) and compared to th...

Computed tomography (CT) dosimetry normally uses an ionization chamber 100 mm long to estimate the computed tomography dose index (CTDI), however some reports have already indicated that small devices could replace the long ion chamber to improve quality assurance procedures in CT dosimetry. This paper presents a novel dosimetry system based in a commercial phototransistor evaluated for CT dosi...

Background: The grading evaluation of atlas based auto-segmentation (ABAS) of organs at risk (OARs) in thorax was studied. Materials and Methods: Forty patients with thoracic cancer were included in this study, and for each thirteen thoracic OARs were delineated by an experienced radiation oncologist. The patients were randomly grouped into the training and the test dataset (20 each). The inves...

Introduction: To improve anatomical atlases, we tried to create a printable 3D atlas of rabbit's anatomy based on the Anaglyph. Methods: In this study, twenty white rabbits euthanized and dissected. All 3D images were reconstructed by means of "stereo photo maker (SPM®)" software. Results: By this atlas, users can easily understand nomenclature, the topography and, certainly, the transpo...