摘要:
A method is provided for optimizing a contrast injection function for CT imaging. The method includes injecting, with an injector pump, a test bolus of a contrast agent into a subject. The method also includes computing, on a processor, an impulse enhancement function. The method also includes determining, on a processor, a target enhancement function for a region of interest. The method also includes determining, with a processor, a plurality of parameters for a functional form for a contrast injection function in a time domain. The method also includes determining for the contrast injection function a constraint. The method also includes determining, with a processor, particular values for the plurality of parameters, which satisfy the constraint and minimize a difference between a value of an enhancement function and the target enhancement function computed in the time domain at discrete time periods without use of a Fourier transform.
摘要:
One embodiment includes a method of predicting a position of a target site inside a body using surrogates is provided. The method includes transforming surrogate measurements and target positions into different representations by applying an operator, establishing a special relationship between the transformed surrogate measurements and the transformed target positions, and continuously predicting the target position from the transformed surrogate measurements and the established special relationship.
摘要:
A method is provided for optimizing a contrast injection function for CT imaging. The method includes injecting, with an injector pump, a test bolus of a contrast agent into a subject. The method also includes computing, on a processor, an impulse enhancement function. The method also includes determining, on a processor, a target enhancement function for a region of interest. The method also includes determining, with a processor, a plurality of parameters for a functional form for a contrast injection function in a time domain. The method also includes determining for the contrast injection function a constraint. The method also includes determining, with a processor, particular values for the plurality of parameters, which satisfy the constraint and minimize a difference between a value of an enhancement function and the target enhancement function computed in the time domain at discrete time periods without use of a Fourier transform.
摘要:
A system and method for indirectly monitoring the position of a target inside a body is disclosed. The method includes generating position data associated with one or more surrogate devices and predicting a location of the target from the position data based on a target position model that establishes a relationship between an actual location of the target and the position data of the one or more surrogate devices. The method also includes determining that the predicted location of the target deviates from the actual location of the target when an analysis of an error prediction model results in a confidence threshold being exceeded.
摘要:
A system and method for indirectly monitoring the position of a target inside a body is disclosed. The method includes generating position data associated with one or more surrogate devices and predicting a location of the target from the position data based on a target position model that establishes a relationship between an actual location of the target and the position data of the one or more surrogate devices. The method also includes determining that the predicted location of the target deviates from the actual location of the target when an analysis of an error prediction model results in a confidence threshold being exceeded.
摘要:
One embodiment includes a method of predicting a position of a target site inside a body using surrogates is provided. The method includes transforming surrogate measurements and target positions into different representations by applying an operator, establishing a special relationship between the transformed surrogate measurements and the transformed target positions, and continuously predicting the target position from the transformed surrogate measurements and the established special relationship.
摘要:
Methods and systems for determining fractional regional ventilation are disclosed. A method includes obtaining first and second lung image data indicative of a first phase and a second phase of a respiratory cycle, respectively, determining an apparent mass ratio k based on the first lung image data and the second lung image data, determining first and second spatially matched lung image data, each including N voxels, based on the first lung image data and the second lung image data, and determining at least one fractional regional ventilation value (FRV value), in accordance with a first equation FRV(n)=(k·ρ2_n−ρ1_n)/ρ1_n. The value of n is a voxel index, ρ1_n is indicative of a density of a voxel n of the first spatially matched lung image data, and ρ2_n is indicative of a density of a voxel n of the second spatially matched lung image data.