University of Twente Student Theses
Partial volume and T1 correction in brain magnetic resonance spectroscopy imaging : improving data processing in order to determine brain glutamate levels in patients who experienced a psychosis.
Morsinkhof, L.M. (2019) Partial volume and T1 correction in brain magnetic resonance spectroscopy imaging : improving data processing in order to determine brain glutamate levels in patients who experienced a psychosis.
PDF
2MB |
Abstract: | Purpose: To correct glutamate concentrations measured using magnetic resonance spectroscopy imaging at 7 Tesla for partial volume and T1 effects in order to perform a more accurate evaluation of brain glutamate levels in patients who experienced a psychosis. Methods: Glutamate was denoted as the sum of glutamate and glutamine (Glx) with the total amount of creatine (tCr) as scaling factor. Anatomical data were used to obtain probability fraction maps. These maps were corrected for the voxel bleeding effect in order to relate them to the Glx/tCr maps. Based on these fraction maps and subject specific grey and white matter Glx/tCr concentrations partial volume correction was performed. Subsequently the maps were corrected for the effect of T1 relaxation. The Wilcoxon signed rank test was used to evaluate the effect of the corrections in several brain regions. Results: Statistically significant differences in Glx/tCr concentrations were detected in each of the regions. Partial volume correction resulted in an increase of the Glx/tCr concentration in in cortical grey matter, caudate, putamen en thalamus, and a decrease in white matter and the pallidum. Conclusion: After partial volume and T1 correction the Glx/tCr concentrations calculated per region were in line with previous studies. Although the actual concentrations were not known, based on comparison of the calculated Glx/tCr concentrations with literature it can be suggested that the corrected concentrations are more accurate than the uncorrected. It has to be evaluated if partial volume and T1 correction result in a more accurate comparison Glx/tCr concentrations between patients who experienced a psychosis and healthy control subjects. |
Item Type: | Essay (Master) |
Faculty: | TNW: Science and Technology |
Subject: | 44 medicine, 50 technical science in general |
Programme: | Technical Medicine MSc (60033) |
Link to this item: | https://purl.utwente.nl/essays/79606 |
Export this item as: | BibTeX EndNote HTML Citation Reference Manager |
Repository Staff Only: item control page