Conforming to safe RF power limits, this is the first work reporting MRI sequence dependent artifact size of DBS leads in refractory Parkinson's patients and exploring various sequence limits to minimize the artifactual signal void
within clinically feasible image resolution and hardware limitations for PD patients.
However, a distinct flow-related signal void
usually indicates a spinal AVF.
Also, MRI can demonstrate multiple areas of signal void
in the hemangiomas, which represent vessels.
Methemoglobin, with its shortT1 relaxation time on T1-weighted imaging, is easily identified in the membranous labyrinth because of the distinct contrast between it and the surrounding bony signal void
of the otic capsule.
A keen search is advised when assessing for the signal void
of gas, as can be seen in the setting of pneumatosis or free air; extraluminal gas is more difficult to identify on MR compared to CT.
On MRI, arteriovenous malformations are composed of large tortuous often serpiginous arterial and venous vessels with multiple areas of signal void
due to the rapid blood flow (Figure 1).