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A novel gamma GLM approach to MRI relaxometry comparisons
- Source :
- Magnetic resonance in medicine, vol 84, iss 3, Magnetic Resonance in Medicine
- Publication Year :
- 2020
- Publisher :
- eScholarship, University of California, 2020.
-
Abstract
- Author(s): Kapre, Rohan; Zhou, Junhan; Li, Xinzhe; Beckett, Laurel; Louie, Angelique Y | Abstract: PurposeTo demonstrate that constant coefficient of variation (CV), but nonconstant absolute variance in MRI relaxometry (T1 , T2 , R1 , R2 ) data leads to erroneous conclusions based on standard linear models such as ordinary least squares (OLS). We propose a gamma generalized linear model identity link (GGLM-ID) framework that factors the inherent CV into parameter estimates. We first examined the effects on calculations of contrast agent relaxivity before broadening to other applications such as analysis of variance (ANOVA) and liver iron content (LIC).MethodsEightnmodels including OLS and GGLM-ID were initially fit to data obtained on sulfated dextran iron oxide (SDIO) nanoparticles. Both a resampling simulation on the data as well as two separate Monte Carlo simulations (with and without concentration error) were performed to determine mean square error (MSE) and type I error rate. We then evaluated the performance of OLS/GGLM-ID on R1 repeatability and LIC data sets.ResultsOLS had an MSE of 4-5× that of GGLM-ID as well as a type I error rate of 20-30%, whereas GGLM-ID was near the nominal 5% level in the relaxivity study. Only OLS found statistically significant effects of MRI facility on relaxivity in an R1 repeatability study, but no significant differences were found in a resampling, whereas GGLM was more consistent. GGLM-ID was also superior to OLS for modeling LIC.ConclusionsOLS leads to erroneous conclusions when analyzing MRI relaxometry data. GGLM-ID factors in the inherent CV of an MRI experiment, leading to more reproducible conclusions.
- Subjects :
- Generalized linear model
Relaxometry
Iron Overload
Mean squared error
Coefficient of variation
Iron
Biomedical Engineering
Contrast Media
MRI relaxometry
030218 nuclear medicine & medical imaging
03 medical and health sciences
0302 clinical medicine
Resampling
Statistics
Humans
Radiology, Nuclear Medicine and imaging
gamma GLM
repeatability
Full Paper—Biophysics and Basic Biomedical Research
Mathematics
Full Paper
Contrast (statistics)
Repeatability
Magnetic Resonance Imaging
Brain Disorders
coefficient of variation
Nuclear Medicine & Medical Imaging
Liver
relaxivity
030217 neurology & neurosurgery
Type I and type II errors
Subjects
Details
- Database :
- OpenAIRE
- Journal :
- Magnetic resonance in medicine, vol 84, iss 3, Magnetic Resonance in Medicine
- Accession number :
- edsair.doi.dedup.....b915af20d3531ae8e2a6ba2736576f3f