Concentric Loops
Doty Scientific introduces next generation high performance surface coils for Magnetic Resonance Imaging and Spectroscopy
Concentric Loops
A better way to make dual-frequency surface coils.
- Two channel MR probe for both transmit and receive only.
- Improved sensitivity by 25% at both low and high frequencies.
- Efficient RF delivery at both frequencies below SAR limitations.
- Nearly identical B1 field profiles for efficient 1H-decoupling and cross polarization transfer.
- Uniform B1 homogeneity in the central region.
- Excellent channel isolation with no traps on both coils.
- For all sizes and frequencies –
The new coils will be made in standard 20mm, 40mm, and
80mm sizes. Other sizes will also be available upon request. - 1H/13C, 1H/31P, 1H/23Na, 1H/17O…
Figure 1. New Concentric Loop Coils
Coil performance and B1 field homogeneity
Figure 2: Simulated B1 field mapping for the low-frequency (13C, 32 MHz) outer loop (left) and for the high-frequency (1H, 128 MHz) inner loop (right) coils, respectively. Here, loop dimensions are defined as 85 mm for outer diameter of the outer loop and 68 mm for inner diameter of the inner loop. B0 is perpendicular to the plane of the page (z=0 plane). The smaller semi-ellipsoid outline defines the region used for the calculation of the mean pw90 over the central FOV for both coils. The larger semi-ellipsoid defines the extent of the lossy sample (k=80, σ=0.7 S/m). The mean Π/2 at 100 W is 70 μs for 1H and 130 μs for 13C.
