Respiratory motion is a significant obstacle to the use of quantitative perfusion in clinical practice. Increasingly complex motion correction algorithms are being developed to correct for respiratory motion. However, the impact of these improvements on the final diagnosis of ischemic heart disease has not been evaluated. The aim of this study was to compare the performance of four automated co...

UNLABELLED PET imaging of nonhuman primates (NHPs) requires correction of head motion if the subjects are scanned awake and their heads are unrestrained, because the NHPs move their heads faster and more frequently than human subjects. This work focuses on designing and validating 2 motion-correction algorithms for awake NHP brain PET imaging. METHODS Two motion-correction methods were implem...

Patient motion has long been recognised as a problem in MR imaging. A 1997 study of 297 first-time adult MRI patients showed 6.4% of scans were of impaired diagnostic quality due to motion [1]. These numbers are described by the authors as being inline with an earlier German study of 21,000 cases (8-17% scans of impaired diagnostic quality) [2]. Despite modern hardware and reconstruction, motio...

INTRODUCTION – Correction of head motion artifacts is essential for clinically acceptable image quality. This is especially important for long scans, such as DTI, fMRI, and high-resolution structural scans. Prospective motion-correction using stereovision systems [1,2] have been suggested to perform real-time head motion-correction without necessitating the acquisition of additional MR-based na...

Introduction The long scan duration makes spectroscopic imaging (SI) experiments particularly susceptible to motion-induced artifacts. Prospective motion correction based on an optical tracking system [1] has recently been proposed for 2D SI in the human brain [2]. Additionally, retrospective phase correction using the interleaved reference scan (IRS) method has been applied for the correction ...

There has been conflicting data in the literature regarding the use of wide navigator echo (NE) acceptance windows in combination with adaptive motion correction for magnetic resonance coronary angiography (MRCA). This in part may be due to the use of a fixed correction factor when applying the adaptive motion-correction algorithm, which may potentially result in miscorrection of the imaging sl...

INTRODUCTION – Due to the prolonged acquisition time, correction for rigid-body motion artifacts is essential for diagnostic image quality in DTI. Prospective motion correction using a monovision camera system and a checkerboard marker has previously been used to correct for rigid head motion artifacts [1,2]. In this study, we use a more sophisticated marker design to improve prospective optica...

INTRODUCTION Prospective motion correction using an external tracking device is an effective technique for motion correction in fMRI [1]. It has advantages over image-based correction methods [2], which require full volume coverage to compute motion parameters in a full six degrees of freedom (6DOF). The ultimate goal of this project is to use prospective correction to perform fMRI experiments ...

PURPOSE To implement a nonrigid autofocus motion correction technique to improve respiratory motion correction of free-breathing whole-heart coronary magnetic resonance angiography acquisitions using an image-navigated 3D cones sequence. METHODS 2D image navigators acquired every heartbeat are used to measure superior-inferior, anterior-posterior, and right-left translation of the heart durin...

BACKGROUND We present a study performing motion correction (MC) of PET using MR navigators sampled between other protocolled MR sequences during simultaneous PET/MR brain scanning with the purpose of evaluating its clinical feasibility and the potential improvement of image quality. FINDINGS Twenty-nine human subjects had a 30-min [(11)C]-PiB PET scan with simultaneous MR including 3D navigat...