Assessing the fit of 3D printed bolus from CT, optical scanner and photogrammetry methods

This study quantitatively compares the fits of boluses designed from different imaging modalities. A head phantom was imaged using three systems: a CT simulator, a 3D optical scanner, and an interchangeable lens camera. Nose boluses were designed and 3D printed from each modality. A 3D printed phantom with air gaps of known thicknesses was used to calibrate mean HU to measure air gaps of unknown thickness and assess the fit of each bolus on the head phantom. The bolus created from the optical scanner data resulted in the best fit, with a mean air gap of 0.16  mm. Smoothing of the CT bolus resulted in a more clinically suitable model, comparable to that from the optical scanner method. The bolus produced from the photogrammetry method resulted in air gaps larger than 1 mm in thickness. The use of optical scanner and photogrammetry models have many adva ntages over the conventional bolus-from-CT method, however workflow should be refined to ensure accuracy if implemented clinically.
Source: Australasian Physical and Engineering Sciences in Medicine - Category: Biomedical Engineering Source Type: research

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Source: Cancer Medicine - Category: Cancer & Oncology Authors: Tags: ORIGINAL RESEARCH Source Type: research
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Source: Radiation Research - Category: Physics Authors: Tags: Radiat Res Source Type: research
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Source: Practical Radiation Oncology - Category: Cancer & Oncology Source Type: research
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Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research
Abstract PURPOSE: Using a 200 Head and Neck cancer (HNC) patient cohort, we employ patient similarity based on tumor location, volume, and proximity to organs at risk to predict radiation-associated dysphagia (RAD) in a new patient receiving intensity modulated radiation therapy (IMRT). MATERIAL AND METHODS: All patients were treated using curative-intent IMRT. Anatomical features were extracted from contrast-enhanced tomography scans acquired pre-treatment. Patient similarity was computed using a topological similarity measure, which allowed for the prediction of normal tissues' mean doses. We performed feat...
Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology - Category: Radiology Authors: Tags: Radiother Oncol Source Type: research
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Source: Johnson and Johnson - Category: Pharmaceuticals Tags: Innovation Source Type: news
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Source: Journal of Thoracic Disease - Category: Respiratory Medicine Tags: J Thorac Dis Source Type: research
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Source: Diseases of the Colon and Rectum - Category: Gastroenterology Tags: Resident’s Corner Source Type: research
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Source: Radiotherapy and Oncology - Category: Radiology Authors: Tags: Original Article Source Type: research
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