Simple-tune Small-Animal RF Litz or Litzcage Modules

MRI coils with best sensitivity, homogeneity, and convenience.

Doty RF Litz  or Litzcage Coil Modules

You wouldn't consider buying something like a computer or spectrum analyzer without reviewing and comparing detailed specifica­tions.  You owe it to yourself to apply the same critical standards when purchasing an rf coil.  With rf coils, the most important criteria usually are S/N, B₁ homogeneity, and reliability.  For S/N, simply check the 90° pulse spec.  Regardless of whether it's single or double resonance, shielded or unshielded, linear or circular polarization, short or long, surface or volume, one simple relationship always holds for a given voxel size and other conditions:

where τ₉₀ is the   90° pulse length (we specify for a hard pulse) and P is the transmitter power. Many of the smaller coils listed in the tables have S/N better by factors of 1.5 to 3 than published birdcages of similar size and tuning. Our ¹H Litzcages have truly extraordinary robustnesss, ease-of-use with widely differing samples, homogeneity, and S/N.

Does your τ₉₀ drop by less than a factor of two (at constant P ) when your sample diameter drops by a factor of 2?  Do you have difficulty matching and tuning with certain samples?  Are you tired of tweaking numerous adjustments to try to get acceptable B₁ homogeneity with your samples?  If you answered yes to any of the above, you should inquire whether a Doty Litz or Litzcage coil could improve your results.

Easy tuning                     

Doty Litz and Litzcage coils are easily tuned and matched to a full range of samples with negligible loss in efficiency, channel separation, or symmetry.  The tuning range is an order of magnitude greater than with conventional coils and tuning methods.

Versatile, Robust Design

In Doty Imaging Modules, the rf Litz or Litzcage coils are enclosed in the rf shield and packaged in an integrated aesthetic cover. Coil dimensions are customized to your specifications.

Exceptional Sensitivity

The linear Litz or CP (cross polarization) Quadrature Litzcage coils have SNR 10-15% higher than with conventional linear or quadrature birdcages of similar dimensions  – and often much better. The B₁ homogeneity is 10-30% better and the coils have improved B₀ homogeneity.  Simple-tune Litz coils can be easily double-tuned.

With all the improvements, customers are often surprised that there is also usually a substantial cost advantage in choosing Doty coils.

Preprint available – RF Coil Technology for Small-Animal MRI.
Download a preprint of “RF Coil Technology for Small-Animal MRI”, by F. David Doty, George Entzminger, Jatin Kulkarni, Kranti Pamarthy and John P. Staab, published in [NMR Biomed. 2007; 20: 304-325, published online in Wiley Interscience, at www.interscience.wiley.com, DOI: 10.1002/nbm.1149].

Mouse Brain Images

This T₂ spin-echo experiment on a live mouse brain using a 2 cm linear Litz coil in a 4.7 T horizontal magnet demonstrated substantially better B₁ homogeneity and better S/N than a quadrature birdcage of similar dimensions. The Litz coil easily tuned and matched to any load in less than a minute.

Images courtesy of Dr. Joel R. Garbow, Washington University, St. Louis, MO.

To view additional images...

Also, please view the images taken using our Knee RF Coils

Check for coil specifications in the tables below .

Custom coils are also available.

What coil length do you want?