User profiles for J.A. Helpern
Joseph A. HelpernNew Vision Research Verified email at musc.edu Cited by 19134 |
Diffusional kurtosis imaging: the quantification of non‐gaussian water diffusion by means of magnetic resonance imaging
… In particular, we find sharp differences between the diffusional kurtosis in white and gray
matter, confirming the preliminary results reported by Jensen and Helpern (2). We believe that …
matter, confirming the preliminary results reported by Jensen and Helpern (2). We believe that …
MRI quantification of non‐Gaussian water diffusion by kurtosis analysis
JH Jensen, JA Helpern - NMR in Biomedicine, 2010 - Wiley Online Library
Quantification of non‐Gaussianity for water diffusion in brain by means of diffusional kurtosis
imaging (DKI) is reviewed. Diffusional non‐Gaussianity is a consequence of tissue structure …
imaging (DKI) is reviewed. Diffusional non‐Gaussianity is a consequence of tissue structure …
White matter characterization with diffusional kurtosis imaging
Diffusional kurtosis imaging (DKI) is a clinically feasible extension of diffusion tensor
imaging that probes restricted water diffusion in biological tissues using magnetic resonance …
imaging that probes restricted water diffusion in biological tissues using magnetic resonance …
Estimation of tensors and tensor‐derived measures in diffusional kurtosis imaging
This article presents two related advancements to the diffusional kurtosis imaging estimation
framework to increase its robustness to noise, motion, and imaging artifacts. The first …
framework to increase its robustness to noise, motion, and imaging artifacts. The first …
Three‐dimensional characterization of non‐gaussian water diffusion in humans using diffusion kurtosis imaging
…, JH Jensen, A Ramani, JA Helpern - NMR in Biomedicine: An …, 2006 - Wiley Online Library
Conventional diffusion tensor imaging (DTI) measures water diffusion parameters based on
the assumption that the spin displacement distribution is a Gaussian function. However, …
the assumption that the spin displacement distribution is a Gaussian function. However, …
Assessment of relative brain iron concentrations using T2‐weighted and T2*‐weighted MRI at 3 Tesla
…, JC Deniau, RA Knight, JA Helpern - Magnetic resonance …, 1994 - Wiley Online Library
In this paper a new method is presented for the relative assessment of brain iron concentrations
based on the evaluation of T 2 and T 2 * ‐weighted images. A multiecho sequence is …
based on the evaluation of T 2 and T 2 * ‐weighted images. A multiecho sequence is …
Increased iron‐related MRI contrast in the substantia nigra in Parkinson's disease
…, GG Brown, JC Deniau, NM Buderer, JA Helpern - Neurology, 1995 - AAN Enterprises
Article abstract—Elevated iron levels in the substantia nigra (SN) of the brain in Parkinson's
disease (PD) may mediate lipid peroxidative reactions, promoting SN neuronal death. To …
disease (PD) may mediate lipid peroxidative reactions, promoting SN neuronal death. To …
Low brain magnesium in migraine
…, A Vande‐Linde, SR Levine, JA Helpern… - … : The Journal of …, 1989 - Wiley Online Library
Brain magnesium was measured in migraine patients and control subjects using in vivo 31‐PhosphorusNuclear
Magnetic Resonance Spectroscopy, pMg and pH were calculated from …
Magnetic Resonance Spectroscopy, pMg and pH were calculated from …
Revealing mesoscopic structural universality with diffusion
Measuring molecular diffusion is widely used for characterizing materials and living organisms
noninvasively. This characterization relies on relations between macroscopic diffusion …
noninvasively. This characterization relies on relations between macroscopic diffusion …
Correction of motional artifacts in diffusion-weighted MR images using navigator echoes
RJ Ordidge, JA Helpern, ZX Qing, RA Knight… - Magnetic resonance …, 1994 - Elsevier
Patient motion can seriously degrade the quality of diffusion-weighted MR images obtained
using standard 2DFT imaging procedures. The main source of error arises from an MR …
using standard 2DFT imaging procedures. The main source of error arises from an MR …