Quantitative Monte Carlo-based brain dopamine transporter SPECT imaging.

Objective: Brain dopamine transporter imaging with I-123-labeled radioligands is technically demanding due to the small size of the imaging target relative to the spatial resolution of most SPECT systems. In addition, I-123 has high-energy peaks which can penetrate or scatter in the collimator and be detected in the imaging energy window. The aim of this study was to implement Monte Carlo (MC)-based full collimator-detector response (CDR) compensation algorithm for I-123 into a third-party commercial SPECT reconstruction software package and to evaluate its effect on the quantitative accuracy of dopaminergic-image analysis compared to a method where only the geometric component of the CDR is compensated.

Safety in simultaneous EEG-fMRI at 3 T: temperature measurements.

Background: In simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), safety of the EEG equipment is ensured by the manufacturer only for localizers and fMRI sequences. To conduct a clinically feasible simultaneous EEG-fMRI study, other sequences, e.g.

Data quality in fMRI and simultaneous EEG-fMRI.

Object: To evaluate functional magnetic resonance imaging (fMRI) and simultaneous electroencephalography (EEG)-fMRI data quality in an organization using several magnetic resonance imaging (MRI) systems.

Materials And Methods: Functional magnetic resonance imaging measurements were carried out twice with a uniform gel phantom on five different MRI systems with field strengths of 1.5 and 3.