IV New Patents

during surgery and the making of accurate and precise bone cuts conforming to the selected prostheses.

4843245

SCINTILLATION DETECTOR FOR TOMOGRAPHS

Roger Lecomte, Sherbrooke, Canada assigned to Universite de Sherbrooke

The present invention relates to a scintillation detector for a tomograph comprising at least two scintillators having different scintillation charac- teristics and being optically coupled to a photo- detector.

4843321

METHOD FOR VOLUME LOCALIZED SPECTRAL EDITING

OF NMR SIGNALS PRODUCED BY METABOLITES CONTAINING

COUPLED SPINS

Christopher H Sotak assigned to General Elec- tric Company

An NMR method for acquiring the in vivo pro- ton spectra of spin-spin coupled metabolites em- ploys a pair of stimulated echo pulse sequences (90-TE/2-9041-90-TE/2). The period TE/2 is set to optimize the signal components produced by the coupled spins of the metabolites. The value of period tl is different for the two pulse sequences and the difference between the two resulting NMR echo signals provides the desired spectra.

4843322

METHOD FOR PRODUCING MULTI-SLICE NMR IMAGES

Gary H Glover assigned to General Electric Company

In an NMR imaging system spins in a set of slices are simultaneously excited by a com- posited RF excitation pulse in each NMR pulse sequence of a scan. The composite RF excitation pulse contains a set of terms, each of which ex- cites a separate slice and each of which is modulated by a ky-dependent phase factor. The

ky-dependent phase factor causes the iamge of each slice to be offset in the resulting reconstruc- tion so that each slice image can be separated from the others.

4843323

DEVICE AND METHOD FOR ADJUSTING A

RADIOFREQUENCY ANTENNA OF A NUCLEAR MAGNETIC RESONANCE APPARATUS

Robert Encellaz, Tong Yong C Ng, Beynes, France assigned to Thomson-CGR

A device and method are provided for adjusting a radiofrequency antenna of a nuclear magnetic resonance apparatus. In the invention, using capacities preset in the factory, the antenna detuning of an NMR apparatus is limited to a range such that the standing wave rate of a high frequency line which conveys the radiofrequency signal is limited. This line is cut and, at a short distance, a tuning adjustment circuit is inserted. This circuit may be automated: the electric ad- justment motors, thus spaced away, do not dist- urb the magnetic fields of the apparatus. By measuring the real part of the admittance at the input of the adjustment circuit and the phase shift between voltage and current this circuit can be adjusted.

4843618

RADIOGRAPHY

John E Best, Christopher A G LeMay, Godfrey N Hounsfield, Robert J Froggatt, Oxon, United Kingdom assigned to EM1 Limited

In a computerized tomographic apparatus in which the requisite absorption data are derived by rotating a source of fanned radiation around a body to be examined and detecting radiation emergent from a cross-sectional slice of the body at many times during the rotation the data, when assembled into sets relating to parallel beam paths through the slice, tends to relate to beam paths which are non-uniformly spaced across the slice. Some techniques for processing such data to produce a representation of the variation of absorption of said radiation over the.slice should preferably have said data presented thereto in the form of sets relating to substantially uniformly spaced, parallel beam paths. The application of this invention provides con-