Mitsubishi Denki Kabushiki Kaisha

Kiyoshi Yoda

Satoshi Fujimura

Susumu Nishihara

Tadatoshi Yamada

Hidenobu Itagaki

Hiroshi Nishizawa

Toru Oka

Kazunori Ikegami

Hidenobu Sakamoto

Keiichi Matsuo

Yukimasa Aoki

Nobuyuki Kanematsu

Isamu Uetomi

Yoshifuru Saitou

Kazushi Hanakawa

A control apparatus for a radiotherapy irradiation system in which a calculation time required for calculation to be performed after restrictions are modified is shortened. The control apparatus includes a unit for setting an initial solution indicating an initial irradiated beam weight, a unit for inputting restrictions according to a prescription, and a unit for setting an evaluation function under the restrictions. The control apparatus further includes a unit for iteratively calculating the evaluation function until the evaluation function is minimized and determining an irradiated beam weight optimizing irradiation, and unit for outputting an optimal solution indicating an optimal irradiated beam weight to the irradiation system. After restrictions are modified, a new evaluation function is set under the modified restrictions. An irradiated beam weight is then determined for optimizing irradiation. At this time, the initial solution setting unit adopts the previous optimal solution indicating an optimal irradiated beam weight, which is obtained before the restrictions are modified, as the initial solution indicating the initial irradiated beam weight.

Control apparatus for controlling radiotherapy irradiation system

An intensity modulated radio therapy (IMRT) dosimeter measuring a three-dimensional absorption dose distribution in a transparent plastic phantom readily and accurately. In the IMRT dosimeter, radiation beams are directed to a phantom assembly having a scintillation fiber block sandwiched between two blocks of the phantom. As an intensity of light proportional to the radiation beam is emitted from one side of the scintillation fiber block, its profile is measured by an image sensor. Then, the three-dimensional absorption dose distribution is obtained from the light intensity distribution data. By summing the three-dimensional absorption dose distribution data measured with the radiation beam at different angles, an integrated three-dimensional absorption dose distribution in the phantom can be calculated readily and accurately.

Absorption dose measuring apparatus for intensity modulated radio therapy

An X-ray mammography apparatus for more reliable and less painful diagnosis, by providing means for elongating the breast using gravity or force of suction. In one form, the patient is horizontally positioned on a bed having a hole for elongating the breast. An X-ray source and a film table are located under the bed, thereby allowing an X-ray beam going horizontally through the patient's breast. An advantage is that a cancer near the chest wall can be more reliably detected.

X-ray mammography apparatus

The ratio a between an energy distribution vector U,is calculated by using a density distribution P, and a desired energy distribution vector V to obtain an energy source density distribution P/a. Thus, the intensity of an energy distribution can be varied, and the irradiation of unnecessary portions of the human body can be avoided when an tumor in the human body is irradiated with an energy distribution.

Method of forming energy distribution

An irradiation dose calculating unit can solve a problem of a conventional irradiation dose calculating unit in that since irradiation doses from portals are empirically determined, it is likely that optimum irradiation doses are not established for a target and a critical organ. A prescription data input section is used for a physician to input prescription data designating doses to a target and a critical organ. First and second object function calculating sections each calculate predefined indices, and obtain a first object function representing the level of satisfaction for the critical organ and a second object function representing the level of satisfaction for the target and critical organ. The irradiation doses from the portals are calculated based on these object functions such that the prescription data are satisfied.

Irradiation dose calculation unit, irradiation dose calculation method and recording medium

A radiation detecting section including scintillation fibers is arranged in a one-dimensional, two-dimensional or three-dimensional manner. A multichannel amplitude analyzer can obtain an incident position of radiation in the radiation detecting section, and a radiation dose rate at the incident position depending upon a signal having amplitude according to a difference in arrival time between two input signals. A microcomputer carries out inverse problem analysis to estimate a radiation source distribution or a spatial radiation intensity distribution.

Radiation detector and method of detecting radiation

Disclosed herein is a method and an apparatus for controlling or determining and estimating an object system which controls or determines parameters for specifying the object system and estimates an internal condition of the object system based on a measured value obtained for the object system. The method and apparatus compute a function characteristic distribution of the object system as a function of variable parameters using a boundary element method or finite element method. An equation is set by making equivalance between the computed distribution and a predetermined distribution. Values of parameters can be obtained by solving the equation.

Method of manufacturing, determining and designing an object

In ordering products, a customer selects a product from a product list stored in a remote computer system via a communication line. A sensor detects the customer size information and transmits it to the remote computer, thus enabling the remote computer to select a product having an appropriate size. Subsequently, on a monitor display, product image is superimposed on the customer body image. The fit evaluation is automatically performed by the local computer system. Depending on the fit of the product, the customer tries different products until placing an order.

Method of and system for ordering products

A magnetic resonance apparatus comprising a magnet for generating a stationary magnetic field, a magnetic field gradient coil for generating gradient magnetic field pulses, and a radio frequency coil disposed within the magnet and the magnetic field gradient coil for transmitting radio frequency pulses and receiving a magnetic resonance signal. A radio frequency shield member is also disposed between the magnetic field gradient coil and the radio frequency coil. The radio frequency shield member includes a plurality of electrically conductive strips each extending in the direction of axis of the magnet and at least partly overlapping with respect to a neighboring conductor strip and a plurality of non-conductors sandwiched between the adjacent two conductive strips. A ring-shaped conductor having a capacitor inserted therein is disposed at each of the axial ends of the radio frequency coil along arcuated end portion of the radio frequency coil.

Magnetic resonance apparatus

A magnetic resonance imaging method and apparatus for obtaining images of slices of a body placed in a static magnetic field. During the sampling of one NMR signal, an additional second gradient magnetic field is impressed on the body to acquire data. These data are additionally sampled during each sampling. This enables the number of data to be increased and the number of repetitions to be reduced, thereby accomplishing a Fourier transformation at a higher speed.

Magnetic resonance imaging method and apparatus therefor

A radio frequency coil for nuclear magnetic resonance imaging comprises two annular conductors which are coaxially disposed at opposite ends of a prescribed axis and at least one pair of longitudinal conductor groups which are symmetrically disposed in parallel to the prescribed axis and extend longitudinally from one annular conductor to the other. Each longitudinal conductor group comprises a plurality of longitudinally-extending electrical conductors whose ends are secured and electrically connected to the annular conductors. The longitudinal conductors are preferably in the form of electrically conducting wires, tubes, or plates. The annular conductors can be in the form of one-piece rings or in the form of one or more pairs of arcuate plates which are electrically connected with one another and disposed about the prescribed axis in the form of a ring. Electrically conducting guard rings which are electrically insulated form the inner surface of the coil may be coaxially disposed inside the annular conductors.

Radio frequency coil for nuclear magnetic resonance imaging

A radio frequency coil for nuclear magnetic resonance imaging comprises at least one pair of arcuate H-shaped members which are disposed about a longitudinal axis so as to form a tube. A variable capacitor means for adjusting the resonant frequency of the coil is connected across the feeding points of the coil. A balanced feed circuit comprising a balanced impedance matching circuit and a balanced-to-unbalanced converter is connected across the feeding points. An unbalanced current from a transceiver is converted into balanced currents which are fed to the feeding points.

A high frequency coil for nuclear magnetic resonance comprises a saddle coil formed by interposing electric insulator members between adjacent ones of a plurality of metal straps. The metal straps are copper straps, and the electric insulator members are capacitors or air gaps.

High frequency coil for an NMR apparatus

A nuclear magnetic resonance imaging method having the first step of exciting a nuclear spin in a volume of an object in a static magnetic field, the second step of applying first, second and third gradients, and the third step of producing a spin echo signal under the second gradient in accordance with the nuclear spin which has the step of applying a high frequency pulse in which the nuclear spin is approximately tilted at 116.degree. as an exciting pulse in the first step.

Nuclear magnetic resonance imaging method

An RF field generator and detector comprising an RF coil having an inductance and at least one conductor which includes at least first and second separated parts arranged to form stray capacitance between them, capacitors for impedance matching which are connected to the RF coil, and a balanced-to-unbalanced transformer by which a balanced load composed of the RF coil and the capacitors is coupled to an unbalanced RF transmitter and receiver, the stray capacitance being adjusted thereby to equivalently reduce the inductance of the RF coil.

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Tokyo, Japan

Kiyoshi Yoda