Device and method for spatiotemporal reconstruction of a moving vascular pulse wave in the brain and other organs
View Patent ↗The brain appears to have organized cardiac frequency angiographic phenomena with such coherence as to qualify as vascular pulse waves. Separate arterial and venous vascular pulse waves may be resolved. This disclosure states the method of extracting a spatiotemporal reconstruction of the cardiac frequency phenomena present in an angiogram obtained at faster than cardiac frequency. A wavelet transform is applied to each of the pixel-wise time signals of the angiogram. If there is motion alias then instead a high frequency resolution wavelet transform of the overall angiographic time intensity curve is cross-correlated to high temporal resolution wavelet transforms of the pixel-wise time signals. The result is filtered for cardiac wavelet scale then pixel-wise inverse wavelet transformed. This gives a complex-valued spatiotemporal grid of cardiac frequency angiographic phenomena. It may be rendered with a brightness-hue color model or subjected to further analysis.
1. A method of extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency, wherein in an instance of no significant motion alias by a time-indexing-conserving mathematical transform of a pixel-wise time signals, filtering for cardiac scale, and inverse mathematical transformation.
2. A method of extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency, wherein in an instance of significant motion alias by a high temporal resolution time-indexing-conserving mathematical transform of a pixel-wise time signals, a high frequency time-indexing-conserving mathematical transform of the overall angiographic intensity curve, a pixel-wise cross correlation of these, filtering for cardiac scale, and inverse mathematical transformation.
3. A method of extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency, wherein in an instance of no significant motion alias, the method comprises:
receiving angiographic data consisting of n by m pixels by q frames into computer memory;
reformatting the angiographic data with a processor to generate an n by m array of time signals, each q samples long;
applying a complex valued time-indexing-conserving mathematical transform by the processor to each pixel-wise time signal to generate an n by m array of time-indexing-conserving mathematical transforms;
filtering the pixel-wise time-indexing-conserving mathematical transforms for cardiac frequency by the processor;
performing on the pixel-wise time-indexing-conserving mathematical transforms data an inverse mathematical transform by the processor into time domain and reformatting into q frames of n by m pixels; and
rendering each frame as an image with a brightness hue color model to represent a complex datum in each pixel with the processor.
4. A method of extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency, wherein in the instance of significant motion alias, the method comprises:
summing an angiographic signal for each time frame by a processor for all n by m pixels to generate an overall angiographic intensity point for each of q frames to generate an overall angiographic time intensity curve of length q;
applying a high frequency resolution time-indexing-conserving mathematical transform by the processor to the angiographic time intensity curve;
reformatting then angiographic data by the processor as an n by m array of time signals each of length q;
performing a high temporal time-indexing-conserving mathematical transformation by the processor on each pixel-wise time signal to generate an n by m array of high temporal resolution time-indexing-conserving mathematical transforms;
cross correlating in domain, each pixel-wise high temporal resolution time-indexing-conserving mathematical transform by a single high frequency resolution time-indexing-conserving mathematical transform of an overall angiographic time intensity curve by the processor;
inverse mathematical transforming an n by m array of cross-correlated signals in domain to generate an n by m array of time domain time signals each of length q by the processor; and
reformatting the n by m time signals of length a by the processor into q frames of n by m pixels, each complex valued.
5. A device for extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency wherein in an instance of no significant motion alias, the device comprises:
a processor configured to receive angiographic data consisting of n by m pixels by q frames into a computer memory;
the processor further configured to reformat the angiographic data to generate an n by m array of time signals, each q samples long;
the processor further configured to apply a complex valued time-indexing-conserving mathematical transform to each pixel-wise time signal to generate an n by m array of time-indexing-conserving mathematical transforms;
the processor further configured to filter the pixel-wise time-indexing-conserving mathematical transforms for cardiac frequency;
the processor further configured to perform on the pixel-wise time-indexing-conserving mathematical transforms data an inverse mathematical transform into time domain and reformatting into q frames of n by m pixels; and
the processor further configured to render each frame as an image with a brightness hue color model to represent a complex datum in each pixel.
6. A device for extracting cardiac frequency phenomena from an angiographic study obtained at faster than cardiac frequency, wherein in an instance of significant motion alias, the device comprises:
a processor configured to sum the angiographic signal for each time frame by the processor for all n by m pixels to generate an overall angiographic intensity point for each of the q frames to generate an overall angiographic time intensity curve of length q;
the processor further configured to apply a high frequency resolution time-indexing-conserving mathematical transform to the angiographic time intensity curve;
the processor further configured to reformat then the angiographic data as an n by m array of time signals each of length q;
the processor further configured to perform a high temporal time-indexing-conserving mathematical transformation on each such pixel-wise time signal to generate an n by m array of high temporal resolution time-indexing-conserving mathematical transforms;
the processor further configured to cross correlate in domain, each pixel-wise high temporal resolution time-indexing-conserving mathematical transform by the single high frequency resolution time-indexing-conserving mathematical transform of an overall angiographic time intensity curve;
the processor further configured to inverse mathematical transform the n by m array of cross-correlated signals in domain to generate an n by m array of time domain time signals each of length q; and
the processor further configured to reformat the n by m time signals of length a into q frames of n by m pixels, each complex valued.