Synchronisation system with trigger delay
A synchronisation system comprises aa sensor arrangement to detect a trigger base event. An analysis module and an arithmetic unit are configured to access prior information on a time delay between the sensor arrangement's detection of the trigger base and a starting point of an acquisition time interval for acquiring imaging data. The starting point is computed of the acquisition time interval from the detected trigger base event and the prior information of the time delay. The time delay between the sensor arrangement's detection of the trigger base event and the acquisition time interval may vary between individual subjects, but for each individual subject the time delay is well reproducible and hence on a per subject basis may be calibrated for.
1 . A synchronization system comprising
a sensor arrangement configured to detect a trigger base,
an analysis module configured to access prior information on a time delay between the sensor arrangement's detection of the trigger base and an arithmetic unit to compute a starting point of an acquisition time interval for acquiring imaging data and
compute the starting point of the acquisition time interval from the detected trigger base event and the prior information of the time delay wherein the analysis module and the arithmetic unit are configured to access the prior information in the form of image information on a subject to be examined and on the basis of the accessed image information derive the time delay between the sensor arrangement's detection of the trigger base and a starting point of an acquisition time interval for acquiring imaging data.
2 . A computer program stored on a non-transitory computer readable medium, wherein the computer program is configured to control the synchronization system of claim 1 and comprising instructions to:
access the prior information on a time delay between the sensor arrangement's detection of the trigger base and the starting point of an acquisition time interval for acquiring imaging data and
compute the starting point of the acquisition time interval from the detected trigger base event and the prior information of the time delay.
3 . A computer program stored on a non-transitory computer readable medium, wherein the computer program is configured to control calibration of the time delay for the synchronization system of claim 1 and comprising instructions to:
perform the direct measurement of the actual instant of the trigger base event and of the acquisition time interval,
simultaneously detect the trigger base event by a sensor arrangement and
determine the time delay between the actual instant of the trigger base event and the detection of the trigger base event by the sensor arrangement.
4 . The synchronization system of claim 1 , wherein the analysis module and the arithmetic unit are configured to derive anatomical distances and sizes of the subject to be examined from the accessed image information and derive said time delay form the derived anatomical distances and sizes.
5 . The synchronization system of claim 1 , wherein the analysis module is provided with a machine-learning module to return said time delay from the accessed image information.
6 . The synchronization system of claim 1 , wherein the computation of the starting point of the acquisition time interval also accounts for the sensor arrangement's latency time.
7 . The synchronization system of claim 1 , wherein the prior information on the time delay has been previously calibrated for a subject to be examined by imaging in a calibration procedure to measure the acquisition time interval by a direct measurement of the trigger base event and the acquisition time interval.
8 . A method of calibration of the time delay for a synchronization system of claim 1 , wherein the acquisition time interval is measured in a calibration examining separate from a synchronised acquisition of imaging data and by:
(i) direct measurement of the actual instant of the trigger base event and of the acquisition time interval; and
(ii) simultaneously detecting the trigger base event by the sensor arrangement.
9 . The synchronization system of claim 1 , wherein
the sensor arrangement is controlled to detect trigger base events at different locations in a subject's body to be examined and
the analysis module and the arithmetic unit are configured to derive a pulse transit velocity from the time differences between the detected trigger base events and the derived anatomical distances between these different locations.