By using a multiple receiving coil composed of receiving coils, an imaging portion of a subject is subjected to a first pulse sequence to create n sensitivity images (701 to 703) fewer than the examination images. When these sensitivity images are created, an NMR signal is measured for only the low-frequency region of the k space. A second pulse sequence from which a phase encode step is removed is conducted to create m (m>n) examination images (704, 705) of the subject by using the receiving coils. When sensitivity distributions (707, 708) of the receiving coils are determined for the sensitivity images (701 to 703), and if there are no sensitivity distributions corresponding to the slice positions of the examination images (704, 705), they are determined by slice interpolation using the sensitivity distributions (701 to 703), and the aliasing artifacts of the examination images (704, 705) are removed by matrix operation by using the sensitivity distributions (707, 708).

Magnetic resonance imaging device

A surgical instrument including a switching mechanism which allows a surgeon to selectively advance or retract a staple driver and/or cutting member within a staple cartridge. In various embodiments, the surgical instrument can include a handle, a trigger operatively coupled to the handle, a firing drive, and an end effector. The firing drive can include a first ratchet assembly configured to advance a cutting member in the end effector and a second ratchet assembly configured to retract the cutting member. The trigger can include first and second pawls pivotably mounted thereon which are configured to be selectively engaged with the first and second ratchet assemblies, respectively. In at least one embodiment, the trigger can be configured to slide between a first position in which the first pawl is engaged with the first ratchet assembly and a second position in which the second pawl is engaged with the second ratchet assembly.

Surgical instrument having a directional switching mechanism

Magnetic resonance imaging apparatus

PURPOSE: To develop a superconducting magnetic resonance (MR) imager that provides direct access to the patient and permits interactive MR-guided interventional procedures. MATERIALS AND METHODS: A 0.5-T superconducting magnet that allows a region of vertical access to the patient was designed and constructed. This magnet was integrated with newly designed shielded gradient coils, flexible surface coils, and nonmagnetic displays and with position-monitoring probes and device-tracking instrumentation. RESULTS: The magnet homogeneity was 12.3 ppm, and the gradient field was linear to within 1% over an imaging region 30 cm in diameter. The signal-to-noise ratio was 10% higher than in a comparable 0.5-T superconducting imager. Images were obtained in several anatomic regions with use of routine pulse sequences. Interactive image plane selection and near real-time imaging, with use of fast gradient-recalled echo sequences, were demonstrated at a rate of one image every 1.5 seconds. CONCLUSION: MR-guided interv...

Superconducting open-configuration MR imaging system for image-guided therapy.

Magnetic resonance information acquired by a movable magnetic resonance instrument is used to monitor hyperthermia treatments such as tissue ablation. The instrument may include both the magnetic resonance equipment and an energy applicator such as a high intensity focused ultrasound unit. The treatment can be conducted under automatic control after the operator marks a treatment volume on an image of the subject, such as a magnetic resonance image acquired using the movable magnetic resonance instrument. The automatic treatment can be based on interpolation of tissue response curves at plural test points near the treatment volume. The system can also provide automatic supervisory control during manual operation, to prevent application of heat to sensitive anatomical structures.

MRI-guided therapeutic unit and methods

This invention relates to a field mapping fixture for mapping the magnetic fields of a superconducting magnet. Such structures of this type, generally, are capable of measuring the magnetic fields of a relatively small imaging volume.

Field mapping fixture for a superconducting magnet for imaging human limbs

A warm bore cylinder assembly (300, figure 3) having an outer wall 150, an inner wall 152, and a plurality of braces 154, is provided. The outer wall 150 is configured to define an inner exterior portion of a cryostat assembly 110. The outer wall 150 is generally cylindrical, is made of a conductive material, and has an outer wall thickness. The inner wall 152. is disposed radially inwardly of the outer wall 150. The inner wail 152 is generally cylindrical, is made of a conductive material, and has an inner wall thickness. The braces 154, extend along an axial direction defined by the outer wall 150 and the inner wall 152. The plurality of braces 154, 306 are interposed between and join the outer wall 150 and inner wall 152. The plurality of braces define openings 308 disposed between adjacent braces 154. The assembly is particularly for application with a Magnetic Resonance Imaging (MRI) system.

Warm bore cylinder assembly of cryostat

The present invention solves the aforementioned problems by providing a vacuum seal assembly for a high power generator stub shaft which includes a seal stator encircling the stub shaft and a plurality of oil seals disposed on an inner diameter of the seal stator and encircling the stub shaft. Adjacent oil seals form a plurality of seal cavities between the stub shaft and the seal stator, and define gaps between each oil seal and the stub shaft for receiving a lubricant film. At least one seal feed conduit extending through the seal stator into the plurality of seal cavities to provide lubricant to the seal assembly.

Vacuum seal for high speed generator

PROBLEM TO BE SOLVED: To provide a magnetizing coil unit and a method of making a magnetizing coil unit. SOLUTION: A coil includes a solenoid coil having a coiled copper sheet in which the width of the copper sheet is equal to the height of the solenoid coil. A magnetizing assembly comprises a plurality of magnetizing coil units, each of the magnetizing coil units comprising a coiled copper sheets placed in a housing, the housing containing a coolant input port in the bottom of the housing, and a coolant output port placed on the upper part of the housing. COPYRIGHT: (C)2005,JPO&NCIPI

Method and apparatus for magnetizing permanent magnet

PROBLEM TO BE SOLVED: To provide an improved superconducting magnet assemblies and methods for making the same to reduce eddy current in Magnetic Resonance Imaging systems.SOLUTION: The superconducting magnet assembly includes: a superconducting magnet configured to generate a static magnetic field, an iron shield configured to shield the superconducting magnet, and a magnetic gradient coil assembly configured to generate a gradient magnetic field. The superconducting magnet assembly further includes one or more magnetic lamination elements disposed on the iron shield to reduce eddy current induced by the gradient magnetic field in the iron shield. A method is also presented.

Evangelos Trifon Laskaris

Papers

Field mapping fixture for a superconducting magnet for imaging human limbs

Warm bore cylinder assembly of cryostat

Vacuum seal for high speed generator

Method and apparatus for magnetizing permanent magnet

Magnet assembly and method of manufacturing the same