Definition: 'Signal Void'
signal voidType: Term
1. in magnetic resonance imaging, a region emitting no radiofrequency signal, because there are no activated protons in the region (such as flowing blood), because a different element predominates, particularly calcium, or because of uncompensated dephasing, such as occurs at air-tissue interfaces in the lung.
The definition information for signal void is provided by Stedman's. You can search our medical dictionary here.