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E De Vita

Publications and source records attributed to E De Vita.

8 recordsLinked to original sources
PubMed2003

High resolution MRI of the brain at 4.7 Tesla using fast spin echo imaging.

Over recent years, high field MR scanners (3 T and above) have become increasingly widespread due to potential advantages such as higher signal-to-noise ratio. However, few examples of high resolution images covering the whole brain in reasonable acquisition times have been published to date and none have used fast spin echo (FSE), a sequence commonly employed for the acquisition of T(2) weighted images at 1.5 T. This is mostly due to the increased technical challenges associated with uniform signal generation and the increasingly restrictive constraints of current safety guidelines at high field. We investigated 10 volunteers using an FSE sequence optimized to the 4.7 T environment. This sequence allows the acquisition of 17- and 34-slice data sets with an in-plane resolution of approximately 500 microm x 500 microm and a slice thickness of 2 mm, in 5 min 40 s and 11 min 20 s, respectively. The images appear T(2) weighted, although the contrast is due to the combined effects of chosen echo time, magnetization transfer, direct radio frequency saturation and diffusion as well as the T(1) and T(2) relaxation times of the tissue. The result is an excellent detailed visualization of anatomical structures, demonstrating the great potential of 4.7 T MRI for clinical applications. This paper shows that, with careful optimization of sequence parameters, FSE imaging can be used at high field to generate images with high spatial resolution and uniform contrast across the whole brain within the prescribed power deposition limits.

Adult↗
PubMed2001

Spectral editing in (13)C MAS NMR under moderately fast spinning conditions.

Novel procedures for the spectral assignment of peaks in high-resolution solid-state (13)C NMR are discussed and demonstrated. These methods are based on the observation that at moderate and already widely available rates of magic-angle spinning (10--14 kHz MAS), CH and CH(2) moieties behave to a large extent as if they were effectively isolated from the surrounding proton reservoir. Dipolar-based analogs of editing techniques that are commonly used in liquid-state NMR such as APT and INEPT can then be derived, while avoiding the need for periods of homonuclear (1)H--(1)H multipulse decoupling. The resulting experiments end up being very simple, essentially tuning-free, and capable of establishing unambiguous distinctions among CH, CH(2), and --C--/-CH(3) carbon sites. The principles underlying such sequences were explored using both numerical calculations and experimental measurements, and once validated their editing applications were illustrated on a number of compounds.

Journal Article↗
PubMed1999

The spin coherence relaxation in the rotating frame as a microscopy parameter for strongly coupled spin systems.

The transverse relaxation time in the rotating frame T2rho is proposed as an effective parameter to get specific contrast in solid state imaging. Several peculiarities make T2rho an interesting candidate to map dynamics and structure in solids: the effect of the secular spin interaction can be controlled by the experimenter and therefore the relaxation associated with the nonsecular terms, which is particularly sensitive to very slow dynamics, can be observed. In this paper we present preliminary results obtained on polymers and prove the capability of the MARF Imaging, enhanced by a filter based on rotary echo refocusing, to produce images of solids contrasted by T2rho.

Magnetic Resonance Spectroscopy↗
PubMed1990

[A new digital radiology system. The technical considerations and clinical experience].

The authors report their experience with a new digital X-ray film processing system, particularly used in the diagnosis of breast, chest, joint and bone pathologic conditions. The technical features of the system are described, and the results are reported which appear as the most significant in mammography, with better visualization of both microcalcifications and small detail images. The above results are due to the possibility of broad contrast variations and of processing basal X-ray images. The possibility is also stressed of improving the diagnostic value of a technically incorrect radiograph, especially if overexposed, with subsequent dose saving.

Arthrography↗
PubMedDate not supplied

[Ureteral duplication and anomalous symptomatology. Presentation of a case].

The authors report a case of unilateral ureteral duplication with extravesical ureteral orifice evaluated with sonography and confirmed by surgery. The peculiarity of the case is founded on the anomalous clinical findings with poorly significant uroculture and the apparent discrepancy between sonographic and urographic finding. The important rule of sonographic evaluation in early diagnosis of kidney malformations is confirmed.

Child↗