suspicion was raised for neurocysticercosis, mucopolysaccharidosis, spongiform encephalopathy and extensive cystic tumor, for which he underwent an extensive workup, all of which were unremarkable. Careful review of the history revealed similar findings on imaging done two years prior, for an unrelated reason. The imaging findings were finally determined to be consistent with extensive Virchow-Robin spaces, which is a benign finding. He was discharged home, with annual follow-ups, and has been stable since.  

Virchow–Robin spaces are incidental imaging findings with a prevalence rate of 1.6–3% in healthy individuals. Several congenital, vascular, infectious and neoplastic processes could be easily confused with dilated perivascular spaces. The etiology is still a matter of debate; fibrosis and obstruction of lymphatic drainage pathways, myelin loss, ex-vacuo dilatation secondary to brain atrophy, or alterations of arterial wall permeability are some of the proposed pathogenic mechanisms. The fact that these spaces occupied a significant portion of a hemisphere without causing any obvious symptoms in our patient, makes this a very challenging scenario.

Virchow-Robin spaces are considered a benign finding on brain imaging. Extensive Virchow-Robin spaces may present a clinical and imaging challenge, especially in patients presenting with neurological symptoms, that may be unrelated to them. Clinicians should keep this important imaging finding in mind to avoid unnecessary expensive workup.