Sodium-23 MRI of whole spine at 3 Tesla using a 5-channel receive-only phased-array and a whole-body transmit resonator

详细信息    查看全文

• 作者：Matthias Malzacher¹ ; ^{matthias.malzacher@medma.uni-heidelberg.de" class="auth_mail" title="E-mail the corresponding author} ; Raffi Kalayciyan¹ ; Simon Konstandin¹ ; Stefan Haneder² ; ³ ; Lothar R. Schad¹
• 关键词：Sodium MRI ; receive-only surface coil ; spine MRI
• 刊名：Zeitschrift für Medizinische Physik
• 出版年：2016
• 出版时间：March 2016
• 年：2016
• 卷：26
• 期：1
• 页码：95-100
• 全文大小：807 K

文摘

Sodium magnetic resonance imaging (²³Na MRI) is a unique and non-invasive imaging technique which provides important information on cellular level about the tissue of the human body. Several applications for ²³Na MRI were investigated with regard to the examination of the tissue viability and functionality for example in the brain, the heart or the breast. The ²³Na MRI technique can also be integrated as a potential monitoring instrument after radiotherapy or chemotherapy. The main contribution in this work was the adaptation of ²³Na MRI for spine imaging, which can provide essential information on the integrity of the intervertebral disks with respect to the early detection of disk degeneration.

In this work, a transmit-only receive-only dual resonator system was designed and developed to cover the whole human spine using ²³Na MRI and increase the receive sensitivity. The resonator system consisted of an already presented ²³Na whole-body resonator and a newly developed 5-channel receive-only phased-array. The resonator system was first validated using bench top and phantom measurements. A threefold SNR improvement at the depth of the spine (∼7 cm) over the whole-body resonator was achieved using the spine array. ²³Na MR measurements of the human spine using the transmit-only receive-only resonator system were performed on a healthy volunteer within an acquisition time of 10 minutes. A density adapted 3D radial sequence was chosen with 6 mm isotropic resolution, 49 ms repetition time and a short echo time of 540 μs. Furthermore, it was possible to quantify the tissue sodium concentration in the intervertebral discs in the lumbar region (120 ms repetition time) using this setup.