[Adult intramedullary gliomas]. / Tumeurs gliales intramédullaires de l'adulte : la série du rapport.

OBJECTIVES: Intramedullary gliomas are rare tumors accounting for less than 4% of all primary central nervous system tumors. The aims of this retrospective multicenter study were to assess their natural outcome as well as management. METHODS AND MATERIALS: We studied 332 patients from 1984 to 2011. Histopathological examination revealed 72% ependymomas (94% were low grade tumors), 24% astrocytomas (29% were high grade tumors), 2.4% mixed gliomas and 1.7% oligodendrogliomas. RESULTS: The mean age at diagnosis was 42.4 years for ependymomas, with male predominance, versus 39.6 years for astrocytomas. Pain was the most common initial presentation. In 20% of cases, astrocytomas were biopsied alone, but more than 80% of ependymomas had surgical resection. Radiotherapy and chemotherapy were reserved for malignant tumors, especially if they were ependymomas. The 5-year survival rate was 76.8% for astrocytomas and 94.5% for ependymomas. Histology, functional status prior to surgery, and tumor grade are among the prognostic factors. CONCLUSION: Our study showed that surgical treatment of gliomas is well codified, at least for ependymomas, but adjuvant treatment continues to play a marginal role in the management even in astrocytomas, which are infiltrative tumors.

Transmission of wireless neural signals through a 0.18 µm CMOS low-power amplifier.

In the field of Brain Machine Interfaces (BMI) researchers still are not able to produce clinically viable solutions that meet the requirements of long-term operation without the use of wires or batteries. Another problem is neural compatibility with the electrode probes. One of the possible ways of approaching these problems is the use of semiconductor biocompatible materials (silicon carbide) combined with an integrated circuit designed to operate with low power consumption. This paper describes a low-power neural signal amplifier chip, named Cortex, fabricated using 0.18 µm CMOS process technology with all electronics integrated in an area of 0.40 mm(2). The chip has 4 channels, total power consumption of only 144 µW, and is impedance matched to silicon carbide biocompatible electrodes.