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A protocol for evaluating ultrasmall superparamagnetic particles of iron oxide (USPIO) uptake and elimination in cerebral small vessel disease patients was developed and piloted. <i>B</i>₁-insensitive <i>R</i>₁ measurement was evaluated in vitro. Twelve participants with history of minor stroke were scanned at 3-T MRI including structural imaging, and <i>R</i>₁ and <i>R</i>₂* mapping. Participants were scanned (i) before and (ii) after USPIO (ferumoxytol) infusion, and again at (iii) 24–30 h and (iv) one month. Absolute and blood-normalised changes in <i>R</i>₁ and <i>R</i>₂* were measured in white matter (WM), deep grey matter (GM), white matter hyperintensity (WMH) and stroke lesion regions. <i>R</i>₁ measurements were accurate across a wide range of values. <i>R</i>₁ (<i>p</i> &lt; 0.05) and <i>R</i>₂* (<i>p</i> &lt; 0.01) mapping detected increases in relaxation rate in all tissues immediately post-USPIO and at 24–30 h. <i>R</i>₂* returned to baseline at one month. Blood-normalised <i>R</i>₁ and <i>R</i>₂* changes post-infusion and at 24–30 h were similar, and were greater in GM versus WM (<i>p</i> &lt; 0.001). Narrower distributions were seen with <i>R</i>₂* than for <i>R</i>₁ mapping. <i>R</i>₁ and <i>R</i>₂* changes were correlated at 24–30 h (<i>p</i> &lt; 0.01). MRI relaxometry permits quantitative evaluation of USPIO uptake; <i>R</i>₂* appears to be more sensitive to USPIO than <i>R</i>₁. Our data are explained by intravascular uptake alone, yielding estimates of cerebral blood volume, and did not support parenchymal uptake. Ferumoxytol appears to be eliminated at 1 month. The approach should be valuable in future studies to quantify both blood-pool USPIO and parenchymal uptake associated with inflammatory cells or blood-brain barrier leak.