T2 Mapping from Super-Resolution-Reconstructed Clinical Fast Spin Echo Magnetic Resonance Acquisitions

Relaxometry studies in preterm and at-term newborns have provided insight into brain microstructure, thus opening new avenues for studying normal brain development and supporting diagnosis in equivocal neurological situations. However, such quantitative techniques require long acquisition times and therefore cannot be straightforwardly translated to in utero brain developmental studies. In clinical fetal brain magnetic resonance imaging routine, 2D low-resolution T2-weighted fast spin echo sequences are used to minimize the effects of unpredictable fetal motion during acquisition. As super-resolution techniques make it possible to reconstruct a 3D high-resolution volume of the fetal brain from clinical low-resolution images, their combination with quantitative acquisition schemes could provide fast and accurate T2 measurements. In this context, the present work demonstrates the feasibility of using super-resolution reconstruction from conventional T2-weighted fast spin echo sequences for 3D isotropic T2 mapping. A quantitative magnetic resonance phantom was imaged using a clinical T2-weighted fast spin echo sequence at variable echo time to allow for super-resolution reconstruction at every echo time and subsequent T2 mapping of samples whose relaxometric properties are close to those of fetal brain tissue. We demonstrate that this approach is highly repeatable, accurate and robust when using six echo times (total acquisition time under 9 minutes) as compared to gold-standard single-echo spin echo sequences (several hours for one single 2D slice)

Assessment of structural connectivity in the preterm brain at term equivalent age using diffusion MRI and T-2 relaxometry: a network-based analysis

Preterm birth is associated with a high prevalence of adverse neurodevelopmental outcome. Non- invasive techniques which can probe the neural correlates underpinning these deficits are required. This can be achieved by measuring the structural network of connections within the preterm infant's brain using diffusion MRI and tractography. We used diffusion MRI and T-2 relaxometry to identify connections with altered white matter properties in preterm infants compared to term infants. Diffusion and T-2 data were obtained from 9 term neonates and 18 preterm- born infants (bor

The use of mannitol in partial and live donor nephrectomy: an international survey

PURPOSE: Animal studies have shown the potential benefits of mannitol as renoprotective during warm ischemia; it may have antioxidant and anti-inflammatory properties and is sometimes used during partial nephrectomy (PN) and live donor nephrectomy (LDN). Despite this, a prospective study on mannitol has never been performed. The aim of this study is to document patterns of mannitol use during PN and LDN. MATERIALS AND METHODS: A survey on the use of mannitol during PN and LDN was sent to 92 high surgical volume urological centers. Questions included use of mannitol, indications for use, physician responsible for administration, dosage, timing and other renoprotective measures. RESULTS: Mannitol was used in 78 and 64\ua0% of centers performing PN and LDN, respectively. The indication for use was as antioxidant (21\ua0%), as diuretic (5\ua0%) and as a combination of the two (74\ua0%). For PN, the most common dosages were 12.5 g (30\ua0%) and 25 g (49\ua0%). For LDN, the most common doses were 12.5 g (36.3\ua0%) and 25 g (63.7\ua0%). Overall, 83\ua0% of centers utilized mannitol, and two (percent or centers??) utilized furosemide for renoprotection. CONCLUSIONS: A large majority of high-volume centers performing PN and LDN use mannitol for renoprotection. Since there are no data proving its value nor standardized indication and usage, this survey may provide information for a randomized prospective study