Wisconsin Alumni Research Foundation

Uti Limited Partnership

Richard Frayne

Charles Milton Strother

Orhan Unal

Hyuk Yu

Zhihao Yang

Abukar Wehelie

Yong Zhou

M Louis Lauzon

Robert Brown

The ability to examine the frequency content of a signal is critical in a variety of fields, and many techniques have been proposed to fill this need, including the Fourier and wavelet family of transforms. One of these, the S-transform, is a Fourier based transform that provides simultaneous time and frequency information similar to the wavelet transform but uses sinusoidal basis functions to produce true frequency and globally referenced phase measurements. It has been shown to be useful in several medical imaging applications but its use is limited due to high computational requirements of the original, continuous form. The described embodiments include a general framework for describing linear time-frequency transforms, using the Fourier, wavelet and S-transforms as examples. As an illustration of the utility of this formalism, a fast discrete S-transform algorithm is developed that has the same computational complexity as the fast Fourier transform.

Signal processing with fast S-transforms

The present invention provides a coating that emits magnetic resonance signals and a method for coating medical devices therewith. The coating includes a paramagnetic metal ion-containing polymer complex that facilitates diagnostic and therapeutic techniques by readily visualizing medical devices coated with the complex.

MR signal-emitting coatings

NMR images indicative of thermal changes in tissues undergoing therapy are produced using a gradient-recalled echo pulse sequence. Prior to therapy a contrast agent which shortens spin T relaxation time is injected into the patient and a reference phase image indicative of proton chemical shift is acquired. Temperature maps are produced in real-time as the therapy is subsequently performed by repeatedly acquiring NMR data, reconstructing measurement phase images and subtracting the reference phase image. The temporal rate at which the temperature maps are produced is increased by segmenting k-space and acquiring less than all the segments during each repetition.

Real time in vivo measurement of temperature changes with contrast enhanced NMR imaging

Growing community of inventors

Calgary, Canada

Richard Frayne