Retrospective review of the EUS images from the false-positive case showed a suspected echo artifact.
This phenomenon is called time/frequency uncertainty principle [32] and can cause "pre-echo" artifacts (i.e., a short noise-like event preceding a signal onset) which can be easily perceived.
In small air collections reverberation artifacts may not be seen, whereas in extensive pneumoperitoneum found pronounced pre-hepatic echoes with sound shadow phenomenon may obscure the underlying abdominal organs [17].
The other 1.5% FPs originated from extra reflection echoes, seam artifacts, catheter sheath, etc.
In this case, the improved DTI methods presented in this paper can also be applied to effectively remove the echo-shifting-induced artifacts in twice-refocused spin-echo DTI.
However, we also live in a time when such blessings, and the people who go with them, are still tagged by some as inauthentic, as erasures rather than expressions of Torah, as destined to echo only as transient artifacts of a confused age.
On the other hand, the SIR technique must be used judiciously with higher performance gradients and parallel imaging to shorten the echo train duration, reducing artifacts and distortions.
Several factors enable the detection of small nodal metastases at DWI. Use of improved echo-planar imaging technology, dedicated coils, and dedicated sequence optimization enables a maximal reduction of echo-planar imaging-related artifacts at a relatively high spatial resolution [ 41].
It should be noted however, that other compression artifacts (pre-echo, birdie, etc).
As susceptibility artifacts increase with echo time [32], this time optimization step also resulted in a further reduction of the size of signal voids.
