We describe the clinical presentation, radiological findings, treatment and outcomes of three patients with delayed leukoencephalopathy occurring after endovascular treatment (EVT) for cerebral aneurysms—a rare, albeit recurring, complication. The symptoms occurred 6 to 12 months following the EVT of the cerebral aneurysm. Characteristic imaging findings included high-signal changes on T2 images in the white matter without diffusion restriction predominantly at the distribution of the vascular territory of the catheterized arteries, coupled with patchy gadolinium enhancement or low susceptibility weighted imaging (SWI) signals within the white-matter lesions. Steroid pulse therapy is the treatment of choice and promptly improves clinical and imaging findings. Tapering or cessation of steroids may result in clinical and imaging relapses; close- and long-term follow-up for patients presenting this complication is warranted.