Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Medicine and Health Sciences
Chronic Obstructive Pulmonary Disease: Thoracic Ct Texture Analysis And Machine Learning To Predict Pulmonary Ventilation, Andrew Westcott, Dante P I Capaldi, David G Mccormack, Aaron D Ward, Aaron Fenster, Grace Parraga
Chronic Obstructive Pulmonary Disease: Thoracic Ct Texture Analysis And Machine Learning To Predict Pulmonary Ventilation, Andrew Westcott, Dante P I Capaldi, David G Mccormack, Aaron D Ward, Aaron Fenster, Grace Parraga
Medical Biophysics Publications
Background Fixed airflow limitation and ventilation heterogeneity are common in chronic obstructive pulmonary disease (COPD). Conventional noncontrast CT provides airway and parenchymal measurements but cannot be used to directly determine lung function. Purpose To develop, train, and test a CT texture analysis and machine-learning algorithm to predict lung ventilation heterogeneity in participants with COPD. Materials and Methods In this prospective study (
An Accurate Registration Of The Bigbrain Dataset With The Mni Pd25 And Icbm152 Atlases., Yiming Xiao, Jonathan C Lau, Taylor Anderson, Jordan Dekraker, D Louis Collins, Terry Peters, Ali R Khan
An Accurate Registration Of The Bigbrain Dataset With The Mni Pd25 And Icbm152 Atlases., Yiming Xiao, Jonathan C Lau, Taylor Anderson, Jordan Dekraker, D Louis Collins, Terry Peters, Ali R Khan
Brain and Mind Institute Researchers' Publications
Brain atlases that encompass detailed anatomical or physiological features are instrumental in the research and surgical planning of various neurological conditions. Magnetic resonance imaging (MRI) has played important roles in neuro-image analysis while histological data remain crucial as a gold standard to guide and validate such analyses. With cellular-scale resolution, the BigBrain atlas offers 3D histology of a complete human brain, and is highly valuable to the research and clinical community. To bridge the insights at macro- and micro-levels, accurate mapping of BigBrain and established MRI brain atlases is necessary, but the existing registration is unsatisfactory. The described dataset includes …
A Framework For Evaluating Correspondence Between Brain Images Using Anatomical Fiducials., Jonathan C Lau, Andrew G Parrent, John Demarco, Geetika Gupta, Jason Kai, Olivia W Stanley, Tristan Kuehn, Patrick J Park, Kayla Ferko, Ali R Khan, Terry M Peters
A Framework For Evaluating Correspondence Between Brain Images Using Anatomical Fiducials., Jonathan C Lau, Andrew G Parrent, John Demarco, Geetika Gupta, Jason Kai, Olivia W Stanley, Tristan Kuehn, Patrick J Park, Kayla Ferko, Ali R Khan, Terry M Peters
Brain and Mind Institute Researchers' Publications
Accurate spatial correspondence between template and subject images is a crucial step in neuroimaging studies and clinical applications like stereotactic neurosurgery. In the absence of a robust quantitative approach, we sought to propose and validate a set of point landmarks, anatomical fiducials (AFIDs), that could be quickly, accurately, and reliably placed on magnetic resonance images of the human brain. Using several publicly available brain templates and individual participant datasets, novice users could be trained to place a set of 32 AFIDs with millimetric accuracy. Furthermore, the utility of the AFIDs protocol is demonstrated for evaluating subject-to-template and template-to-template registration. Specifically, …
Development Of A Computational Method For Assessing Static Field Induced Torque On Medical Implants, Xiao Fan Ding
Development Of A Computational Method For Assessing Static Field Induced Torque On Medical Implants, Xiao Fan Ding
Electronic Thesis and Dissertation Repository
The objective of this thesis is the development of a computational method for finding the torque induced on an object when placed in the static magnetic field of an MR scanner. As a preliminary step, the classic EM problems of a sphere and infinitely long cylinder of linear material was modeled in commercially available simulation software. Upon verification of the parameters implemented, the second step is the simulation of simple objects with realistic material properties, stainless-steel cylinders. Physical cylinders were machined to match those in the simulations and underwent the ASTM standard method for measuring induced torque. An adjacent study …
Hyperpolarized Helium 3 Mri In Mild-To-Moderate Asthma: Prediction Of Postbronchodilator Reversibility, Rachel L Eddy, Sarah Svenningsen, Christopher Licskai, David G Mccormack, Grace Parraga
Hyperpolarized Helium 3 Mri In Mild-To-Moderate Asthma: Prediction Of Postbronchodilator Reversibility, Rachel L Eddy, Sarah Svenningsen, Christopher Licskai, David G Mccormack, Grace Parraga
Medical Biophysics Publications
Background: Longitudinal progression to irreversible airflow limitation occurs in approximately 10% of patients with asthma, but it is difficult to identify patients who are at risk for this transition.
Purpose: To investigate 6-year longitudinal changes in hyperpolarized helium 3 (3He) MRI ventilation defects in study participants with mild-to-moderate asthma and identify predictors of longitudinal changes in postbronchodilator forced expiratory volume in 1 second (FEV1) reversibility
Materials and Methods: Spirometry and hyperpolarized 3He MRI were evaluated in participants with mild-to-moderate asthma in two prospectively planned visits approximately 6 years apart. Participants underwent methacholine challenge at baseline (January 2010 to April 2011) …
Texture Analysis And Machine Learning To Predict Pulmonary Ventilation From Thoracic Computed Tomography, Andrew Westcott
Texture Analysis And Machine Learning To Predict Pulmonary Ventilation From Thoracic Computed Tomography, Andrew Westcott
Electronic Thesis and Dissertation Repository
Chronic obstructive pulmonary disease (COPD) leads to persistent airflow limitation, causing a large burden to patients and the health care system. Thoracic CT provides an opportunity to observe the structural pathophysiology of COPD, whereas hyperpolarized gas MRI provides images of the consequential ventilation heterogeneity. However, hyperpolarized gas MRI is currently limited to research centres, due to the high cost of gas and polarization equipment. Therefore, I developed a pipeline using texture analysis and machine learning methods to create predicted ventilation maps based on non-contrast enhanced, single-volume thoracic CT. In a COPD cohort, predicted ventilation maps were qualitatively and quantitatively related …
Oscillometry And Pulmonary Magnetic Resonance Imaging In Asthma And Copd, Rachel L Eddy, Andrew Westcott, Geoffrey N Maksym, Grace Parraga, Ronald J Dandurand
Oscillometry And Pulmonary Magnetic Resonance Imaging In Asthma And Copd, Rachel L Eddy, Andrew Westcott, Geoffrey N Maksym, Grace Parraga, Ronald J Dandurand
Medical Biophysics Publications
Developed over six decades ago, pulmonary oscillometry has re-emerged as a noninvasive and effort-independent method for evaluating respiratory-system impedance in patients with obstructive lung disease. Here, we evaluated the relationships between hyperpolarized