Publications by authors named "Tom Purdie"

Article Synopsis
  • Implementing quality assurance for data in automated pipelines and image analysis helps prevent biases and misinterpretations.
  • This study validates the effectiveness of convolutional neural networks (CNNs) in detecting dental artifacts in head and neck CT images across multiple external datasets, showing that transfer learning enhances performance.
  • Results showed the highest accuracy (AUC of 0.92) when using larger resampling grids with transfer learning, while smaller grids or datasets did not yield better results.
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Enabling automated pipelines, image analysis and big data methodology in cancer clinics requires thorough understanding of the data. Automated quality assurance steps could improve the efficiency and robustness of these methods by verifying possible data biases. In particular, in head and neck (H&N) computed-tomography (CT) images, dental artifacts (DA) obscure visualization of structures and the accuracy of Hounsfield units; a challenge for image analysis tasks, including radiomics, where poor image quality can lead to systemic biases.

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Background: Since the Intergroup 0116 study was published in 2000, adjuvant postoperative chemoradiotherapy using CT-planned and 3D conformal/intensity-modulated radiotherapy has been offered routinely to fit patients with resected gastric cancer at Princess Margaret Hospital .The objective of this study was to analyze patterns of disease recurrence with respect to the radiotherapy volumes.

Methods: For the date and site (local, locoregional, or distant) of the first recurrence, medical records were reviewed for all patients treated at Princess Margaret Hospital with adjuvant chemoradiotherapy for resected gastric adenocarcinoma (January 1, 2000 to November 30, 2009).

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Introduction: With the anticipation of improved outcomes, especially for patients with early-stage non-small cell lung cancer, stereotactic body radiation therapy (SBRT) has been rapidly introduced into the thoracic radiation oncology community. Although at first glance lung SBRT might seem methodologically similar to conventional radiotherapy, there are important differences in its execution that require particular consideration. The objective of this paper is to highlight these and other issues to contribute to the safe and effective diffusion of lung SBRT.

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The introduction of volumetric X-ray image-guided radiotherapy systems allows improved management of geometric variations in patient setup and internal organ motion. As these systems become a routine clinical modality, we propose a daily quality assurance (QA) program for cone-beam computed tomography (CBCT) integrated with a linear accelerator. The image-guided system used in this work combines a linear accelerator with conventional X-ray tube and an amorphous silicon flat-panel detector mounted orthogonally from the accelerator central beam axis.

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