In common MRI applications each examination required a dedicated coil. Toshiba took a very close look to the individual functions of these coils and created a concept that contains coils for the three basic acquisition area's: head, anterior and posterior body. These coils are designed in such a way that they can be seamless combined for cross boundary acquisitions.
Usually MR examinations are organ specific, which means that coils are developed for dedicated examinations. Therefore coil exchange prior to each new examination is common practice. Toshiba decided to look into details of the individual coils and separated the anterior from the posterior section of each coil. So the Atlas concept comprises of a Spine coil, a Body coil and a split able Head coil. We have build the individual coil segments in such a way that they collect seamless information from the scanned object located at the border of each coil segment.
In the Atlas coil concept multiple coils can be connected simultaneously, through coil connectors located on the couch top. In this way we can connect up to 128 elements simultaneously. It is obvious that the system will read out the elements that are in the scan FOV only. Through this design the Atlas coils can maintain on the couch for most of the applications, ensuring dramatically improvements in workflow.
As coil physics define that small elements have a high resolution but a low depth sensitivity, while large elements have a high depth sensitivity but a low resolution, Toshiba decided to combine the best of these characteristics in the Atlas coil concept. This resulted in two rows with relative small elements in the center of the coil, securing high resolution of the center part of the body, and one row with larger elements at both peripheral parts of the coil, taking care of the reception of signals that originates from deeper stuctures in the body. Both Atlas Spine and Atlas Body coil have an identical element configuration.
Another part of the Atlas concept is to have an optimal match between the maximum scan FOV, number of coil elements and number of receiver channels. Since the homogeneity proved to be so good we have extended the maximum scan FOV in X and Y direction to 55 cm, whereas the scan FOV in Z direction remained at 50 cm. With the Atlas coil concept we developed coils in such a way that there are maximum 32 coil elements in the total scan FOV. 16 of these 32 elements can be connected one to one to 16 receiver channel enabling SPEEDER factor of 8x or when the 32 elements are connected to a 32 channel received system, presently Work In Progress, SPEEDER factors of upto 16 times can be achieved. When the 32 elements are connected in QD arrangement the S/N ratio is improvement with 40%.