Intra-fourth-ventricular choroid plexus papilloma miming ependymoma.

ABSTRACT: Choroid plexus papilloma (CPP), a low incidence central nervous system (CNS) tumor, typically develops as an intraventricular neoplasm arising from the epithelium of the choroid plexus. Infratentorial CPP is predominantly clustered in adults with roughly 70% in the fourth ventricle, while supratentorial CPP commonly found in the lateral ventricles, is the most frequent location in children. The clinical and imaging features of CPP are not typical and may induce the misdiagnosis as other types of primary brain tumors. In this paper, we described a fourth-ventricular CPP that was misdiagnosed as ependymoma despite the manipulation of groundbreaking magnetic resonance imaging (MRI) sequences. These findings indicated that CPP should be considered when performing the differential diagnosis of intraventricular neoplasms.

Magnetoelectric Vortex Magnetic Field Sensors Based on the Metglas/PZT Laminates.

This paper describes the route, from simulations toward experiments, for optimizing the magnetoelectric (ME) geometries for vortex magnetic field sensors. The research is performed on the base of the Metglas/Piezoelectric (PZT) laminates in both open and closed magnetic circuit (OMC and CMC) geometries with different widths (W), lengths (L), and diameters (D). Among these geometries, the CMC laminates demonstrate advantages not only in their magnetic flux distribution, but also in their sensitivity and in their independence of the position of the vortex center. In addition, the ME voltage signal is found to be enhanced by increasing the magnetostrictive volume fraction. Optimal issues are incorporated to realize a CMC-based ME double sandwich current sensor in the ring shape with D × W = 6 mm × 1.5 mm and four layers of Metglas. At the resonant frequency of 174.4 kHz, this sensor exhibits the record sensitivity of 5.426 V/A as compared to variety of devices such as the CMC ME sensor family, fluxgate, magnetoresistive, and Hall-effect-based devices. It opens a potential to commercialize a new generation of ME-based current and (or) vortex magnetic sensors.