Publications by authors named "Elizabeth Charles-Edwards"

Background Non-Hodgkin's lymphoma (NHL) accounts for around 4% of new cancer cases annually. Bone marrow involvement is important for staging and management. Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is used increasingly to identify this, in addition to bone marrow biopsy (BMB), which is seen as "gold" reference standard.

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Objective: To evaluate the effects of previous cone biopsy and lesion size on detectability of stage 1a/1b cervical cancer using endovaginal T2- and diffusion-weighted magnetic resonance imaging.

Methods: One hundred and thirteen patients with cervical tumor were imaged using an endovaginal coil with T2-weighted (T2-W) and diffusion-weighted single-shot echo-planar sequences; 85 managed surgically (58 with prior cone biopsy/LLETZ) were evaluated. T2-W images and ADC maps viewed simultaneously were scored positive or negative for tumor and compared with histology at surgery.

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Purpose: Hypoxia in patients with head-and-neck cancer (HNC) is well established and known to cause radiation resistance and treatment failure in the management of HNC. This study examines the role of parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and perfusion computed tomography (CT) as surrogate markers of intratumoral hypoxia, defined by using the exogenous marker of hypoxia pimonidazole and the endogenous marker carbonic anhydrase 9 (CA9).

Methods And Materials: Patients with HNC underwent preoperative DCE-MRI, perfusion CT, and pimonidazole infusion.

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Purpose: To establish apparent diffusion coefficients (ADCs) of invasive cervical carcinoma compared with nontumor cervical epithelium and determine sensitivity and specificity of diffusion-weighted (DW) magnetic resonance (MR) imaging used in conjunction with T2-weighted MR imaging to help detect invasive cervical carcinoma in patients with stage Ia and Ib1 disease.

Materials And Methods: Local research ethics committee approval was obtained with written consent from each subject. Group 1 comprised patients (mean age, 38.

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Dosimetry for targeted radionuclide therapy is necessary for treatment planning and radiation protection. Currently, there are no standard methods either for performing dosimetry or to evaluate the uncertainties inherent in the dosimetric calculations. In this paper, we present an experimental method using polymer gel dosimeters, whereby absorbed-dose distributions resulting from nonuniform distributions of activity may be determined directly from T(2) magnetic resonance imaging (MRI) as well as from scintigraphic images.

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Diffusion-weighted magnetic resonance imaging (DW-MRI) provides image contrast through measurement of the diffusion properties of water within tissues. Application of diffusion sensitising gradients to the MR pulse sequence allows water molecular displacement over distances of 1-20 microm to be recognised. Diffusion can be predominantly unidirectional (anisotropic) or not (isotropic).

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Radiotherapy treatment planning relies on the use of geometrically correct images. This paper presents a fully automatic tool for correcting MR images for the effects of B(0) inhomogeneities. The post-processing method is based on the gradient-reversal technique of Chang and Fitzpatrick (1992 IEEE Trans.

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