Practical experiences in the transfer of clinical protocols between CT scanners with different ATCM systems.

Automatic tube current modulation (ATCM) systems to aid in optimizing dose and image noise have become standard on computed tomography (CT) scanners over the last decade. ATCM systems of the main vendors modulate tube current in slightly different ways, with some using a control parameter related to image noise (e.g.

Comparison of computed tomography dose index in polymethyl methacrylate and nylon dosimetry phantoms.

The use of computed tomography (CT) scanning has been growing steadily. Therefore, CT dose measurement is becoming increasingly important for patient protection and optimization. A phantom is an important tool for dose measurement.

Assessment of tumour size in PET/CT lung cancer studies: PET- and CT-based methods compared to pathology.

Background: Positron emission tomography (PET) may be useful for defining the gross tumour volume for radiation treatment planning and for response monitoring of non-small cell lung cancer (NSCLC) patients. The purpose of this study was to compare tumour sizes obtained from CT- and various more commonly available PET-based tumour delineation methods to pathology findings.

Methods: Retrospective non-respiratory gated whole body [18F]-fluoro-2-deoxy-D-glucose PET/CT studies from 19 NSCLC patients were used.

Measurement of metabolic tumor volume: static versus dynamic FDG scans.

Background: Metabolic tumor volume assessment using positron-emission tomography [PET] may be of interest for both target volume definition in radiotherapy and monitoring response to therapy. It has been reported, however, that metabolic volumes derived from images of metabolic rate of glucose (generated using Patlak analysis) are smaller than those derived from standardized uptake value [SUV] images. The purpose of this study was to systematically compare metabolic tumor volume assessments derived from SUV and Patlak images using a variety of (semi-)automatic tumor delineation methods in order to identify methods that can be used reliably on (whole body) SUV images.

Impact of [¹⁸F]FDG PET imaging parameters on automatic tumour delineation: need for improved tumour delineation methodology.

Purpose: Delineation of tumour boundaries is important for quantification of [(18)F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) studies and for definition of biological target volumes in radiotherapy. Several (semi-)automatic tumour delineation methods have been proposed, but these methods differ substantially in estimating tumour volume and their performance may be affected by imaging parameters. The main purpose of this study was to explore the performance dependence of various (semi-)automatic tumour delineation methods on different imaging parameters, i.

Effects of image characteristics on performance of tumor delineation methods: a test-retest assessment.

Unlabelled: PET can be used to monitor response during chemotherapy and assess biologic target volumes for radiotherapy. Previous simulation studies have shown that the performance of various automatic or semiautomatic tumor delineation methods depends on image characteristics. The purpose of this study was to assess test-retest variability of tumor delineation methods, with emphasis on the effects of several image characteristics (e.

Evaluation of a cumulative SUV-volume histogram method for parameterizing heterogeneous intratumoural FDG uptake in non-small cell lung cancer PET studies.

Purpose: Standardized uptake values (SUV) are commonly used for quantification of whole-body [(18)F]fluoro-2-deoxy-D: -glucose (FDG) positron emission tomography (PET) studies. Changes in SUV following therapy, however, only provide a proper measure of response in case of homogeneous FDG uptake in the tumour. The purpose of this study was therefore to implement and characterize a method that enables quantification of heterogeneity in tumour FDG uptake.

Measuring response to therapy using FDG PET: semi-quantitative and full kinetic analysis.

Purpose: Imaging with positron emission tomography (PET) using (18)F-2-fluoro-2-deoxy-D: -glucose (FDG) plays an increasingly important role for response assessment in oncology. Several methods for quantifying FDG PET results exist. The goal of this study was to analyse and compare various semi-quantitative measures for response assessment with full kinetic analysis, specifically in assessment of novel therapies.