The phenomenon of interplanetary scintillation (IPS) provides an effective method to identify the presence of sub-arcsecond scale structures in radio sources (mainly AGNs) without the need to invoke high-resolution imaging observations. We have analyzed the high-resolution (milliarcsecond) VLBI properties for a sample of IPS sources detected using the Murchison Widefield Array (MWA) 30×30 field-of-view at 162 MHz. The mechanism of scintillation lies in the compactness of the radio source, the distance of the screen, and observing frequency. There are VLBI studies for interstellar scintillation, but no such studies for IPS sources. We noted a strong correlation is found between the compactness and scintillation index for our sample, indicating that stronger scintillating sources are more compact.