MR imaging method and medical device for use in method
AssigneeSimag GmbH
InventorsAndreas Melzer, Martin Busch
Life of this patent
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Abstract
The invention relates to an MR imaging method for representing and determining the position of a medical device inserted in an examination object, and to a medical device used in the method. In accordance with the invention, the device (11) comprises at least one passive oscillating circuit with an inductor (2a, 2b) and a capacitor (3a, 3b). The resonance frequency of this circuit substantially corresponds to the resonance frequency of the injected high-frequency radiation from the MR system. In this way, in a locally limited area situated inside or around the device, a modified signal answer is generated which is represented with spatial resolution.
Claims42
An MR imaging method for imaging and determining the position of a medical device, the medical device having a passive resonance circuit with an inductor and a capacitor, the inductor being integrated into or formed by an unfolding portion of the medical device that at least in part is capable of being unfolded when inserted in an examination object, the method comprising:
- arranging the examination object in an external magnetic field,
- applying high-frequency radiation having a specific resonance frequency essentially equal to a resonance frequency of the passive resonance circuit so that transitions between spin energy levels of the atomic nuclei of the examination object are excited, and MR signals are produced,
- detecting the MR signals as signal responses, which are evaluated and imaged in spatial resolution,
- unfolding the unfolding portion of the device after insertion into the examination object such that the inductor formed by or integrated into the unfolding portion unfolds along with the unfolding portion,
- producing, by means of the device, a changed signal response of the examination object in a locally defined area, and
- detecting the changed signal response of the examination object to determine the position of the medical device.
A medical device that at least in part is capable of being unfolded comprising:
- at least one passive resonance circuit having an inductor and a capacitor, whose resonance frequency is essentially equal to a resonance frequency of an MR imaging system's applied high-frequency radiation, wherein the at least one passive resonant circuit shifts excitation of spin energy levels of atomic nuclei of an examination object to generate an enhanced MR signal in a locally defined area, and wherein a part of the device that is capable of being unfolded forms the inductor or the inductor is integrated into such a part, such that the inductor unfolds along with the device when the device is unfolded.
An MR imaging system for imaging an examination object having a medical device inserted therein, the medical device having a passive resonance circuit with an inductor and a capacitor, the inductor being integrated into or formed by an unfolding portion of the medical device that at least in part is capable of being unfolded when inserted in the examination object, the imaging system comprising:
- an imaging apparatus adapted to apply high-frequency radiation having a specific resonance frequency essentially equal to the resonance frequency of the passive circuit so that transitions between spin energy levels of the atomic nuclei of the examination object are excited, and MR signals are produced,
- the imaging apparatus being further adapted to detect the MR signals as signal responses, which are evaluated and imaged in spatial resolution,
- wherein the medical device modifies the transitions between spin energy levels of the atomic nuclei of the examination object to change the signal response of the examination object in a locally defined area and wherein the imaging apparatus is further adapted to detect the changed signal response of the examination object to determine the position of the medical device.
An MR imaging system comprising:
- a medical device that at least in part is capable of being unfolded, the medical device comprising,
- at least one passive resonance circuit having an inductor and a capacitor, whose resonance frequency is essentially equal to a resonance frequency of an MR imaging system's applied high-frequency radiation,
- wherein the at least one passive resonant circuit shifts excitation of spin energy levels of atomic nuclei of an examination object to generate an enhanced MR signal in a locally defined area, and
- wherein a part of the device that is capable of being unfolded forms the inductor or the inductor is integrated into such a part, such that the inductor unfolds along with the device when the device is unfolded.
An MR imaging method for imaging and determining position of a medical device, the medical device having a passive resonance circuit with an inductor and a capacitor, the inductor being integrated into an unfolding portion of the medical device which is unfoldable in an examination object under examination, the method comprising:
- applying high-frequency radiation to an examination object after the medical device is unfolded therein such that the inductor integrated into the unfolding portion unfolds along with the unfolding portion, the high frequency radiation having a specific resonance frequency approximately equal to a resonance frequency of the passive resonance circuit to excite transitions between spin energy levels of the atomic nuclei of the examination object, and produce MR signals,
- exciting the resonance circuit, wherein the excited resonance circuit amplifies the excitation of transitions between spin energy levels of the atomic nuclei of the examination object in a locally defined area to produce amplified MR signals;
- and
- detecting the amplified MR signals to determine the position of the medical device.
A medical device for use in an MR imaging system, the medical device comprising,
- a passive resonance circuit having an inductor and a capacitor, the inductor being integrated into an unfolding portion of the medical device, such that the inductor unfolds with the unfolding portion of the medical device after insertion in an examination object, wherein
- a resonance frequency of the passive resonance circuit us approximately equal to a resonance frequency of radiation applied by the MR imaging system.
Dependencies are inferred from the claim text.