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101.
Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.  相似文献   
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Female Genital mutilation/cutting (FGM/C) is associated with enduring psychiatric complications. In this study, we investigate the rates of co-morbid abuses and polyvictimization experienced by survivors of FGM/C. This is a sub-analysis of a cohort study examining the patient population at the EMPOWER Center for Survivors of Sex Trafficking and Sexual Violence in New York City. A retrospective chart-review of electronic medical records was conducted for all consenting adult patients who had FGM/C and had an intake visit between January 16, 2014 and March 6, 2020. Of the 80 participants, ages ranged from 20 to 62 years with a mean of 37.4 (SD?=?9.1) years. In addition to FGM/C, participants were victims of physical abuse (43; 53.8%), emotional abuse (35; 43.8%), sexual abuse (35; 43.8%), forced marriage (20; 25%), child marriage (13; 16.3%), and sex trafficking (1; 1.4%). There was a high degree of polyvictimization, with 41 (51.2%) experiencing 3 or more of the aforementioned abuses. Having FGM/C on or after age 13 or having a higher total abuse score was also found to be strong predictors of depression and PTSD. The high rates of polyvictimization among survivors of FGM/C are associated with development of depression and PTSD. Despite co-morbid abuses, patients still attribute substantial psychiatric symptoms to their FGM/C. Health care providers should understand the high risk of polyvictimization when caring for this patient population.

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