Faculty Collaboration Database

Rotator cuff tears: preliminary application of high-resolution MR imaging with counter rotating current loop-gap resonators. Radiology 1986 Sep;160(3):695-9

Date

09/01/1986

Pubmed ID

3737908

DOI

10.1148/radiology.160.3.3737908

Scopus ID

2-s2.0-0022518163 (requires institutional sign-in at Scopus site)   20 Citations

Abstract

A new class of radio frequency (RF) coils for magnetic resonance (MR) imaging and spectroscopy is introduced. The coils consist of two loop-gap resonators of equal diameters positioned along a common axis. They are tuned to the mode in which the current in the two loops flows in opposite directions. These coils are "decoupled" from a uniform excitation field of arbitrary orientation (including circularly polarized fields) by intrinsic decoupling and by means of back-to-back fast recovery diodes. Measurements made with the coils and a phantom saline tank indicate that the signal-to-noise ratio obtainable with these coils is almost identical to that obtained with single loops. Imaging of several anatomic areas, including knee, wrist, and shoulder, has been performed with a 1.5-T MR system that uses circularly polarized RF. A small series of patients with torn rotator cuffs underwent imaging. Difficulties in establishing the diagnosis with MR imaging because of anatomic complexity are illustrated. The value of pulse sequences with long repetition times to increase the signal intensity of fluid in the joint is shown.

Author List

Kneeland JB, Carrera GF, Middleton WD, Campagna NF, Ryan LM, Jesmanowicz A, Froncisz W, Hyde JS

Authors

Guillermo Carrera MD Emeritus Professor in the Radiology department at Medical College of Wisconsin
Lawrence M. Ryan MD Emeritus Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Humans
Knee Joint
Magnetic Resonance Spectroscopy
Models, Structural
Radio Waves
Shoulder Joint
Technology
Wrist Joint