Abstract
The objective of this thesis was to determine the influence of the attenuation correction (optimal attenuation correction method) on the image quality of images of the basal ganglia.
To determine the optimal correction methods, measurements with a striatal phantom were performed. All studies were performed at the Donauspital (Vienna) using a Siemens Symbia T6 gamma camera. Post-processing of striatal phantom studies using the example of 123I DAT scintigraphy was performed on the e-soft and Hermes workstation.
All striatum studies were separately attenuation corrected (CT method, Chang method) on the console, reconstructed and then submitted to a texture analysis (statistics of the first and second order). The visual assessment followed the criteria for the 123I DAT scintigraphy.
Significant information was supplied by the texture analysis and with its tools of the first and second order (texture signs, co-occurrence matrix). Both, the analysis of the texture signs as well as the analysis of the gray value relations could show that the individual low-dose CT attenuation correction provides more precise correction values and higher contrast images of basal ganglia in comparison to the mathematical attenuation correction by Chang. Therefore it is recommended to apply the method of the low-dose CT attenuation correction in the routine of clinical diagnostics of basal ganglia.