The spatial variation of current density in lines with model void defects fabricated using Focused-ion Beam (FIB) milling has been investigated using Magnetic Force Microscopy (MFM). The model defects were designed to systematically simulate the natural void shapes that occur in electromigration failure of current-carrying lines. Inhomogenous current density around the defects manifests itself in the form of atypical asymmetry in the MFM signal near the defects. The extent of the asymmetry is greatly dependent upon the defect geometry. At current densities of 3-5×106 A/cm2, an asymmetry in the MFM signal is clearly visible around defects, such as a (1×1) μ,2 notch and a (1×9) μm2 45°-slanted slit, at the edge of a 10μm wide line. We present a survey of MFM images of various defect structures in current-carrying lines that perturb the homogenous current flow of a straight line.