Improved algorithms in bigeminus cases
When a bigeminus pattern exists, the scanner opened up the pulsing window automatically in the past, independent of the given input units (see image 1). The reason was to create the ability to reconstruct in the right phase of the RR interval. This led to unnecessary radiation for the patient. In the latest software version for the SOMATOM Definition Flash and SOMATOM Definition (syngo CT 2010A), this scan mode can be more dose aware! It is now possible to perform an Adaptive Cardio Sequence with absolute positive milliseconds. This allows an optimization of end-systolic acquisition in case of a bigeminus pattern (See image 2).
A positive absolute delay (ms) is used, with the following parameters:
Scan: 300 to 400 ms
Range: 300 to 400 ms
These settings lead to a pulsing window with a fixed width and therefore to a lower dose.