Johns Hopkins University

Other

Boston Scientific Neuromodulation Corporation

Surgi-vision Inc.

Mri Interventions, Inc.

Bilkent University

General Electric Company

Greatbatch Ltd.

Ihsan Dogramaci Bilkent Universiti

Ergin Atalar

Albert Clark Lardo

Henry R Halperin

Paul Arthur Bottomley

Parag V Karmarkar

Elliot R McVeigh

Ronald David Berger

Hugh Calkins

Robert Charles Susil

Joao Lima

Axel Krieger

Gabor Fichtinger

Louis Litchfield Whitcomb

Ogan Ocali

Onur Ferhanoglu

Niyazi Koray Ertan

Soheil Taraghinia

Justin M Allen

Attila Tanacs

Xiaoming Yang

Iulian Ioan Iordachita

Ananda Kumar

Elliott R McVeigh

Christine McNamara

Pelin Aksit

William Eldelstein

Bliss G Carkhuff

Harry K Charles, Jr

Elias A Zerhouni

Joao A C Lima

William A Edelstein

J Andrew Derbyshire

Abdel-Monem M El-Sharkawy

Emre Kopanoglu

Haydar Celik

Filiz Ece Filci

Shashank Sathyanarayana

Scott B Reeder

Anthony Z Faranesh

Jeffrey C Lestio

Harald Hartmann Quick

Aylin Dogan

Gökhan Cansiz

Kendrick A Shunk

Elias Zerhouin

Elias Zerhouni

Ali Demirci

Vaishali Paliwal

Harald Hartmut Quick

Meiyappan Solaiyappan

Nikolay V Visksenko

Robert Susil

Yigitcan Eryaman

Hugh Caikins

Bilal Taşdelen

Steve Tulley

Bülent Şen

Gwyneth Susil

Volkan Açikel

Christopher Yeung

Redi Poni

Elliott R Mcveigh

Christine Enger Mcnamara

Elliot R Mcveigh

Louis Lichtfield Whitcomb

Elliot Mcveigh

Robert C Susil

In one aspect, in a magnetic resonance imaging system having a gradient coil array comprising a plurality of independent coils distributed about an enclosure, a method of applying currents to said coils is disclosed, which comprises defining a merit function for optimizing at least one feature of any of a magnetic field and an electric field generated by the coils, using a computer processor to optimize the merit function so as to determine an optimal current vector, wherein said element of the current vector provides a current value for application to one of said gradient coils, and applying the currents to said coils.

Gradient array system for MRI and application on diffusion weighted imaging

A multi-channel RF transmitter system including a magnetic resonance imaging device, a multi-channel RF coil array, a control computer receiving required parameters from a user, producing triggering and clock signals and synthesizing input data required for each channel of RF coil array according to imaging scenario to be realized, an interface control module producing basic band MRI signals according to data from the control computer, a signal modulator and control module for modulating MRI signals produced at the interface control module into radio frequency and distribution to channels, a power/data distribution module distributing the produced signals and required DC power, a RF power amplifier module converting digital signal coming from the power/data distribution module into analog signal, amplifying it and transmitting to members of the coil array, a feedback line for track and correction of any errors in RF signal transmitted to the coil array by the power amplifier module.

Multi-channel integrated MRI transmitter system for a magnetic resonance imaging device

According to an embodiment of the present disclosure, disclosed is an apparatus for generating a radio frequency (RF) pulse in a magnetic resonance imaging (MRI) scanner. The apparatus for generating a radio frequency (RF) pulse in a magnetic resonance imaging scanner includes: a control module controlling a power amplifier and a signal generator; the signal generator configured to generate a signal of a predetermined waveform based on control by the control module and supply the generated signal of the predetermined waveform to the power amplifier in electromagnetic connection therewith; a power amplifier amplifying the signal supplied from the signal generator based on the control by control module and outputting the amplified signal to a coil; and the coil serving as an inductor of the power amplifier and transferring the amplified signal to the object so that an object is excited.

Magnetic resonance imaging scanner with coil serving as inductor of power amplifier

An MRI system includes a gantry having a longitudinal axis (herein 'z-axis') and a magnet disposed about the gantry for generating a static magnetic field along the longitudinal axis. Additionally, the system comprises a first gradient magnet for generating a gradient magnetic field along the longitudinal axis; a second gradient magnet for generating a gradient magnetic field along a first transverse direction (herein 'x-axis') orthogonal the longitudinal axis; and a third gradient magnet for generating a gradient magnetic field along a second transverse direction (herein &#x201c;y-axis&#x201d;) orthogonal to the longitudinal axis and the first transverse direction. Magnetic sensors are positioned relative to the gantry to measure gradients of transverse components of magnetic field along one or more of the x, y and z axes. A controller receives measurement signals from the sensors and operates on those signals to determine gradients of the gradient magnetic field along the longitudinal axis.

Spatiotemporal magnetic field monitoring with hall effect sensors during the MRI scan

Provided is a gradient magnetic field generation module using multiple coils to generate a gradient magnetic field. Provided is a gradient magnetic field generation module including: a gradient coil formed inside a main magnet and generating a gradient magnetic field and including a plurality of coils; and a gradient amplifier controlling at least one of a shape of the gradient magnetic field, a strength of the gradient magnetic field, and slew rate of the gradient magnetic field generated by the gradient coil, in which the plurality of coils is grouped into a plurality of coil groups and current which flows in the plurality of coils is independently controlled by the unit of a group by the gradient amplifier.

Gradient magnetic field generation module using plurality of coils so as to generate gradient magnetic field

A system for multi-slice magnetic resonance imaging (MRI) comprises a gradient coil array comprising a plurality of independent coils distributed about an enclosure; and a controller configured to concurrently actuate said plurality of coils so as to generate a spatially-varying magnetic field within said enclosure such that for at least first and second volumetric slices, a magnetic field magnitude associated with at least one location in the first volumetric slice is substantially equal to a magnetic field magnitude associated with a respective location in the second volumetric slice.

Multi-purpose gradient array for magnetic resonance imaging

A method for tracking movement of a movable portion of an interventional device disposed within a natural or artificial body opening is provided. In particular, image data of fiducials is acquired and therefrom an initial position of an interventional device movable portion with respect to a given coordinate system is determined. Next, real time position data from the encoders is acquired as the movable portion is moved from the initial position, and a displaced position from the initial position is determined. From this acquired information, a position of the movable portion in the coordinate system is determined using both the initial position as determined from the image data and the real time displaced position as determined from the encoders.

Method for insertion of a medical device within a body during a medical imaging process

The end-effector includes a sheath and a medical device or needle carrier that is disposed within the interior compartment of the sheath. An aperture is located in a portion of the sheath proximal a distal end of the sheath that is inserted into a natural or artificial cavity. This device is guided by a real-time imager.

Apparatus for insertion of a medical device during a medical imaging process

A system and method for using magnetic resonance imaging to increase the accuracy of electrophysiologic procedures includes an invasive combined electrophysiology and imaging antenna catheter which includes an RF antenna for receiving magnetic resonance signals and diagnostic electrodes for receiving electrical potentials. The combined electrophysiology and imaging antenna catheter is used in combination with a magnetic resonance imaging scanner to guide and provide visualization during electrophysiologic diagnostic or therapeutic procedures, such as ablation of cardiac arrhythmias. The combined electrophysiology and imaging antenna catheter may further include an ablation tip, and be used as an intracardiac device to deliver energy to selected areas of tissue and visualize the resulting ablation lesions.

System and method for magnetic-resonance-guided electrophysiologic and ablation procedures

Herein is disclosed a probe, including a first electrode disposed at least partially on the probe surface, a second electrode disposed at least partially on the probe surface, a first conductor electrically coupled to the first electrode, a second conductor electrically coupled to the second electrode, and a reactive element electrically coupling the first conductor and the second conductor.

MRI compatible medical leads

An MR system and method for tracking a device of an interventional procedure within a scan subject is disclosed. At least two MR projections of the device are acquired, from which 3D coordinates of the device are determined. Subsequent image acquisition is adjusted with respect to the coordinates of the device to guide movement thereof towards target anatomy. The present system and method provide the ability to locate and visualize continuous portions of an interventional device in 3D, and do not require the use of embedded RF localizing coils.

System and method for image-based interventional device tracking and scan plane guidance

In the acquisition of magnetic resonance data from an examination subject according to a pulse sequence that causes radiation into the examination subject of a radiated radio frequency (RF) pulse having a frequency spectrum and a slice profile with a relationship therebetween, the examination subject is substantially simultaneously, with the radiated RF pulse, to a non-linear magnetic field that alters the relationship in the radiated RF pulse between the frequency spectrum and the slice profile. The alteration of this relationship can be used, for example, to reduce the specific absorption rate (SAR) of the examination subject during the acquisition of the magnetic resonance data.

Method and apparatus for reduction of specific absorption rate (SAR) in magnetic resonance data acquisition

In a method for detecting rotational orientation and position tracking of an inductively coupled RF (ICRF) coil using a transmit array system, a conventional body birdcage coil is used, but the quadrature hybrid is eliminated to use the two excitation-channels separately. The transmit array system provides RF excitations such that the body birdcage coil creates linearly polarized and circulating RF pulses instead of a conventional rotational forward polarized excitation. Inductively coupled RF (ICRF) coils can be constructed on catheters for detecting rotational orientation and tracking purposes. The modifications on anatomy and ICRF coil images are different due to the RF excitation scheme such that the ICRF coil can be separated from the anatomy in real-time. After separating the ICRF coil from the anatomy, a color-coded image can be reconstructed, for example.

Magnetic resonance method and apparatus to separate depiction of a tracked item from surrounding anatomy of a patient, using a transmit array system

The end-effector () includes a sheath () and a medical device or needle carrier () that is disposed within the interior compartment () of the sheath. Aperture () is located in a portion of the sheath proximal a distal end of the sheath that is inserted into a natural or artificial cavity. This device is guided by a real-time imager.

Some embodiments are directed to MRI/RF compatible medical interventional devices. A plurality of spaced apart high impedance circuit segments are configured to have a high impedance at a high range of radiofrequencies and a low impedance at a low range of frequencies. The high impedance circuit segments may comprise co-wound coiled inductors and can reduce, block or inhibit RJ-transmission along the lead system () during exposure to RF associated with a high-Held magnet MRI systems, while permuting passage of low frequency physiologic signals, treatments and/or stimuli. The devices can include at least one electrode.

MRI-safe high impedance lead systems

Growing community of inventors

Columbia, MD, United States of America

Ergin Atalar