Magnetic resonance imaging apparatus and method of determining execution order
AssigneeHitachi Medical Corporation
InventorKoichi Arai
Life of this patent
Estimating the term…
Abstract
It has an object to suppress reduction of an examination efficiency caused by limitation of SAR (specific absorption rate) to the minimum level in an examination that plural imaging sequences containing different imaging sequences are consecutively executed. In consideration of the time variation of time average SAR value in the overall examination, the order of executing the imaging sequences is determined so that the SAR value falls within a predetermined range and the waiting time between imaging sequences is minimum. The determination is performed by calculating a waiting time of each of all conceivable execution orders and selecting an execution order having the minimum waiting time.
Claims15
A magnetic resonance imaging apparatus for executing an examination comprising a plurality of imaging sequences, characterized in that the plurality of imaging sequences contain imaging sequences having different time variations in average specific absorption rate of electromagnetic waves within a predetermined time, and the magnetic resonance imaging apparatus comprises:
- an execution order determining unit that determines an execution order of the plurality of imaging sequences so that the average specific absorption rate within the predetermined time falls within a predetermined range and the examination time is shortest;
- and
- an imaging unit that executes the plurality of imaging sequences according to the execution order determined by the execution order determining unit.
A magnetic resonance imaging apparatus for executing an examination comprising a plurality of imaging sequences, the plurality of imaging sequences containing imaging sequences among which time variation of an average specific absorption rate of electromagnetic waves within a predetermined time is different, characterized by comprising:
- a storage unit that stores an execution order which is calculated in advance and determined so that an average specific absorption rate within a predetermined time falls within a predetermined range and an examination time is shortest;
- and
- an imaging unit that reads out the execution order stored in the storage unit and executes the plurality of imaging sequences in the execution order concerned.
An execution order determining method for a plurality of imaging sequences in a magnetic resonance imaging apparatus for executing an examination comprising the plurality of image sequences among which time variation of average specific absorption rate of electromagnetic waves within a predetermined time is different, characterized by comprising:
- a time variation calculating step that calculates a time variation of an average specific absorption rate of electromagnetic waves within a predetermined time in each of the plurality of imaging sequences by using imaging parameters;
- a measurement pattern extracting step that extracts all conceivable measurement patterns each of which is defined as a conceivable execution order of the plurality of imaging sequences;
- an examination time calculating step that calculates an examination time based on each of all the extracted measurement patterns when an examination is executed in the order of the measurement pattern concerned while the average specific absorption rate within the predetermined time falls within a predetermined range;
- and
- an execution order determining step that determines a measurement pattern providing the shortest examination time as an execution order on the basis of the calculated examination time of each of the measurement patterns.
Dependencies are inferred from the claim text.