Publications by authors named "Sami Jeljeli"
Purpose: To develop a 3D distortion-free reduced-FOV diffusion-prepared gradient-echo sequence and demonstrate its application in vivo for diffusion imaging of the spinal cord in healthy volunteers.
Methods: A 3D multi-shot reduced-FOV diffusion-prepared gradient-echo acquisition is achieved using a slice-selective tip-down pulse in the phase-encoding direction in the diffusion preparation, combined with magnitude stabilizers, centric k-space encoding, and 2D phase navigators to correct for intershot phase errors. The accuracy of the ADC values obtained using the proposed approach was evaluated in a diffusion phantom and compared to the tabulated reference ADC values and to the ADC values obtained using a standard spin echo diffusion-weighted single-shot EPI sequence (DW-SS-EPI).
Purpose: Simultaneous PET-MRI improves inflammatory cardiac disease diagnosis. However, challenges persist in respiratory motion and mis-registration between free-breathing 3D PET and 2D breath-held MR images. We propose a free-breathing non-rigid motion-compensated 3D T -mapping sequence enabling whole-heart myocardial tissue characterization in a hybrid 3T PET-MR system and provides non-rigid respiratory motion fields to correct also simultaneously acquired PET data.
View Article and Find Full Text PDFObjectives: Three-dimensional (3D) magnetic resonance elastography (MRE) measures liver fibrosis and inflammation but requires several breath-holds that hamper clinical acceptance. The aim of this study was to evaluate the technical and clinical feasibility of a single breath-hold 3D MRE sequence as a means of measuring liver fibrosis and inflammation in obese patients.
Methods: From November 2020 to December 2021, subjects were prospectively enrolled and divided into 2 groups.
Article Synopsis
- A study compared the diagnostic effectiveness of 18F-FDG PET/MRI and 18F-FDG PET/CT for staging oesophageal and gastro-oesophageal cancer, enrolling participants with newly diagnosed cases and excluding those with previous malignancies.
- Results indicated that 18F-FDG PET/MRI had a higher concordance rate for determining the primary tumor stage compared to PET/CT, but no significant differences were found in nodal or distant metastasis staging between the two imaging methods.
- The study concluded that while 18F-FDG PET/MRI showed slightly better results for T-staging, both imaging techniques performed similarly overall, with PET/MRI identifying additional metastases in some cases.
Purpose: The purpose of this study was to determine if F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (F-FDG PET/MRI) features are associated with contemporaneous metastases in patients with oesophageal/gastroesophageal cancer.
Methods: Following IRB approval and informed consent, patients underwent a staging PET/MRI following F-FDG injection (326 ± 28 MBq) and 156 ± 23 min uptake time. First-order histogram and second-order grey level co-occurrence matrix features were computed for PET standardized uptake value (SUV) and MRI T1-W, T2-W, diffusion weighted (DWI) and apparent diffusion coefficient (ADC) images for the whole tumour volume.
Purpose: Develop a framework for efficient free-breathing simultaneous whole-heart coronary magnetic resonance angiography (CMRA) and cardiac positron emission tomography (PET) on a 3 Tesla PET-MR system.
Methods: An acquisition that enables nonrigid motion correction of both CMRA and PET has been developed. The proposed method estimates translational motion from low-resolution 2D MR image navigators acquired at each heartbeat and 3D nonrigid respiratory motion between different respiratory bins from the CMRA data itself.