A systematic review of (semi-)automatic quality control of T1-weighted MRI scans.

Purpose: Artifacts in magnetic resonance imaging (MRI) scans degrade image quality and thus negatively affect the outcome measures of clinical and research scanning. Considering the time-consuming and subjective nature of visual quality control (QC), multiple (semi-)automatic QC algorithms have been developed. This systematic review presents an overview of the available (semi-)automatic QC algorithms and software packages designed for raw, structural T1-weighted (T1w) MRI datasets.

Impact of cerebral blood flow and amyloid load on SUVR bias.

Background: Despite its widespread use, the semi-quantitative standardized uptake value ratio (SUVR) may be biased compared with the distribution volume ratio (DVR). This bias may be partially explained by changes in cerebral blood flow (CBF) and is likely to be also dependent on the extent of the underlying amyloid-β (Aβ) burden. This study aimed to compare SUVR with DVR and to evaluate the effects of underlying Aβ burden and CBF on bias in SUVR in mainly cognitively unimpaired participants.

Test-Retest Variability of Relative Tracer Delivery Rate as Measured by [C]PiB.

Purpose: Moderate-to-high correlations have been reported between the [C]PiB PET-derived relative tracer delivery rate R and relative CBF as measured using [O]HO PET, supporting its use as a proxy of relative CBF. As longitudinal PET studies become more common for measuring treatment efficacy or disease progression, it is important to know the intrinsic variability of R. The purpose of the present study was to determine this through a retrospective data analysis.

Parametric imaging of dual-time window [F]flutemetamol and [F]florbetaben studies.

Optimal pharmacokinetic models for quantifying amyloid beta (Aβ) burden using both [F]flutemetamol and [F]florbetaben scans have previously been identified at a region of interest (ROI) level. The purpose of this study was to determine optimal quantitative methods for parametric analyses of [F]flutemetamol and [F]florbetaben scans. Forty-six participants were scanned on a PET/MR scanner using a dual-time window protocol and either [F]flutemetamol (N=24) or [F]florbetaben (N=22).

[C]PIB amyloid quantification: effect of reference region selection.

Background: The standard reference region (RR) for amyloid-beta (Aβ) PET studies is the cerebellar grey matter (GMCB), while alternative RRs have mostly been utilized without prior validation against the gold standard. This study compared five commonly used RRs to gold standard plasma input-based quantification using the GMCB.

Methods: Thirteen subjects from a test-retest (TRT) study and 30 from a longitudinal study were retrospectively included (total: 17 Alzheimer's disease, 13 mild cognitive impairment, 13 controls).