Abstract: A sliding sleeve device has an outer cylinder, a circulation hole being provided in the wall of the outer cylinder; and an inner cylinder provided in an inner cavity of the outer cylinder. In an initial state, the inner cylinder and the outer cylinder are fixed to each other to seal the circulation hole. In a first state, the inner cylinder is movable relative to the outer cylinder, thereby unsealing the circulation hole. A protection mechanism is provided in the circulation hole, which has an inner member located on the radially inner side and an outer member located on the radially outer side.

Abstract: Embodiments can provide a computer-implemented method for simultaneous multi-slice pulse wave velocity measurement, the method comprising simultaneously acquiring a plurality of multiple parallel images slices from a medical imaging device; shifting the plurality of image slices through modulation of the line-by-line phase patterns for each slice in the plurality of slices; deriving a plurality of image waveforms from the plurality of slices; measuring a distance between a plurality of imaging planes corresponding to the plurality of image slices; determining, for each of the image waveforms, a time-to marker; determining the temporal shift by calculating the difference between the time-to markers; and computing the pulse wave velocity by dividing the distance between the plurality of imaging planes by the temporal shift.

Abstract: Embodiments can provide a computer-implemented method for simultaneous multi-slice pulse wave velocity measurement, the method comprising simultaneously acquiring a plurality of multiple parallel images slices from a medical imaging device; shifting the plurality of image slices through modulation of the line-by-line phase patterns for each slice in the plurality of slices; deriving a plurality of image waveforms from the plurality of slices; measuring a distance between a plurality of imaging planes corresponding to the plurality of image slices; determining, for each of the image waveforms, a time-to marker; determining the temporal shift by calculating the difference between the time-to markers; and computing the pulse wave velocity by dividing the distance between the plurality of imaging planes by the temporal shift.