Method and apparatus for monitoring a magnetic resonance...

Surgery – Diagnostic testing – Detecting nuclear – electromagnetic – or ultrasonic radiation

Reexamination Certificate

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C600S544000, C600S013000

Reexamination Certificate

active

06198958

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to medical diagnostic and treatment methods and apparatus.
2. Discussion of the Related Art
Transcranial magnetic stimulation (TMS) is a technique for stimulating the human brain non-invasively. TMS uses the principle of inductance to get electrical energy across the scalp and skull without the pain of direct percutaneous electrical stimulation. It involves placing a coil of wire on the scalp and passing a powerful and rapidly changing current through it. This produces a magnetic field which passes unimpeded and relatively painlessly through the tissues of the head. The peak strength of the magnetic field is related to the magnitude of the current and the number of turns of wire in the coil. This magnetic field, in turn, induces a much weaker electrical current in the brain. The strength of the induced current is a function of the rate of change of the magnetic field, which is determined by the rate of change of the current in the coil. In order to induce enough current to depolarize neurons in the brain, the current passed through the stimulating coil must start and stop or reverse its direction within a few hundred microseconds.
TMS is currently used in several different forms. In a first form, called single-pulse TMS, a single pulse of magnetic energy is delivered from the coil to the patient. Repetitive TMS or rTMS, refers to the delivery of a train of pulses delivered over a particular time period. An example of rTMS could be a train of pulses having a 10 Hz repetition rate that lasts for approximately 8 to 10 seconds. In a typical application, this train of pulses is repeated every 30 seconds for up to 20 or 30 minutes.
Magnetic resonance imaging (MRI) is a technique for non-invasive imaging and diagnosis of body organs that uses the interaction between a magnetic field and protons in the body to provide images of body tissues. Functional MRI or fMRI is a subset of this technology and produces images of activated brain regions by detecting the indirect effects of neural activity on local blood volume, flow, and oxygen saturation. MRI systems have been commercially available for a number of years.
The inventors have realized that it would be desirable to combine TMS and MRI technologies in order to provide diagnostic and therapeutic benefits.
Conventionally, however, these two technologies have not been combined for a variety of reasons. First, it has been thought that there may be interactions between the TMS equipment and the MRI equipment due to the fact that both types of equipment generate and use magnetic fields. Therefore, the instantaneous magnetic field associated with the discharge of the TMS coil, which may be on the order of more than two TESLA might interact with the 1.5 TESLA static magnetic field of the MRI system in some unpredictable manner. Second, the discharge of the TMS coil near the sensitive imaging coil of the MRI system might disable or destroy the receiving circuitry within the imaging coil. Third, the mere presence of the TMS coil near the patient's head might contribute artifacts into any images provided by the MRI system. Fourth, the TMS electronics alone might produce artifacts on the images produced by the MRI system.
SUMMARY OF THE INVENTION
In broad terms, one aspect of the present invention provides a method and apparatus for monitoring a patient's MRI during TMS that does not require a time synchronization of the operation of the TMS device and the MRI system.
This aspect of the invention is provided by a method and apparatus for monitoring a magnetic resonance image of a patient during administration of transcranial magnetic stimulation, including a transcranial magnetic stimulation (TMS) device and a magnetic resonance imaging (MRI) system. The system also includes a probe, coupled to the TMS device, the probe being constructed and arranged to deliver transcranial magnetic stimulation, wherein the probe is substantially constructed of non-ferromagnetic material, wherein timing of operation of a TMS device does not need to be synchronized to timing of operation of the MRI system.
In accordance with another aspect of the invention, a probe is provided for delivering the magnetic pulse provided by a transcranial stimulation (TMS) device to a patient wherein the probe is substantially constructed of non-ferromagnetic material.
Within this disclosure the term transcranial magnetic stimulation (TMS) is meant to include both single-pulse TMS and repetitive TMS. With this disclosure, the term magnetic resonance imaging (MRI) is meant to include all types of MRI and functional MRI.


REFERENCES:
patent: 4033334 (1977-07-01), Fletcher et al.
patent: 4736751 (1988-04-01), Gevins et al.
patent: 4949725 (1990-08-01), Raviv et al.
patent: 4951674 (1990-08-01), Zanakis et al.
patent: 4974602 (1990-12-01), Abraham-Fuchs et al.
patent: 4994015 (1991-02-01), Cadwell
patent: 5119816 (1992-06-01), Gevins
patent: 5159929 (1992-11-01), Morris et al.
patent: 5217010 (1993-06-01), Tsitlik et al.
patent: 5220921 (1993-06-01), Ferris et al.
patent: 5269315 (1993-12-01), Leuchter et al.
patent: 5323776 (1994-06-01), Blakeley et al.
patent: 5455162 (1995-08-01), Ives
patent: 5707334 (1998-01-01), Young
patent: 5769778 (1998-06-01), Abrams et al.
patent: 5794620 (1998-08-01), Dossel et al.
patent: 5833600 (1998-11-01), Young
patent: 28 31 099 (1980-01-01), None
patent: 2 307 411 (1998-05-01), None
patent: WO 92/21281 (1992-12-01), None
patent: WO 94/12099 (1994-06-01), None
patent: WO 98/18384 (1998-05-01), None
International Search Report from International Patent Application PCT/US99/08489, filed Apr. 22, 1999.
International Search Report from International Patent Application PCT/US99/13051, filed Jun. 9, 1999.
Ilmoniemi RJ, Virtanen J: “Neuronal reposnses to magnetic stimulation reveal cortical reactivity and connectivity ”, NeuroReport, vol. 8, No. 16, Nov. 10, 1997, pp. 3537-3540.
Ruohonen J: “Transcranical Magnetic Stimulation: Modelling and New Techniques” Dissertation, Department of Engineering Physics and Mathematics Laboratory of Biomedical Engineering Helsinki University of Technology, Dec. 4, 1998, p. 28, paragraph 2; p. 30, paragraph 1; figure 6.
Bohning, D: “Interleaved Transcranial Magnetic Stimulation (TMS) and fMRI”, proceedings of the international society for magnetic resonance in medicine, Sixth Scientific Meeting and Exhibition, Sydney, Australia Apr. 18-24, 1998, vol. 1. p. 508.
Bohning, D: “Echoplanar Bold fMRI of Brain Activation Induced by Concurrent Transcranial Magnetic Stimulation”, Investigative Radiology, vol. 33, No. 6, Jun 1998, pp 336-340.
Bohning, D: “Mapping transcranial magnetic stimulation (TMS) fields in vivo with MRI”, Neuroreport, vol. 8, No. 11, 1997, pp. 2535-2538.
Pascual-Leone, A, et al.: “Effects of Repetitive Transcranial Magnetic Stimulation (rTMS) on Motor Cortex Activity During a Rate Controlled Motor Task as Measured by Functional Magnetic Resonance Imaging (fMRI)”, Neurology, vol. 48, No. 3, (supp. 2), 1997, p. A106.

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