Anterior temporal lobe perivascular spaces
Anterior temporal lobe perivascular spaces are recently recognized special variants of tumefactive perivascular spaces, which can mimic cystic tumors with surrounding edema.
A predilection for women has been reported 1. Age range is wide, from 24 to 86 years old reported 1.
As is the case with perivascular spaces elsewhere, no symptoms directly attributable to the lesion are usually identified 1.
Unlike tumefactive perivascular spaces elsewhere within the brain, anterior temporal lobe perivascular spaces often have surrounding edema (~80%) which can range from mild to extensive 1. Additionally, they are usually associated with a branch of the middle cerebral artery and a focal region of cortical thinning or absence (~90%) 1. Otherwise, they have similar appearances to perivascular spaces elsewhere: internal CSF signal on all sequences and no enhancement 1,2.
The size of the cyst invariably remains stable. Surrounding edema, however, can change over time in a small percentage of cases, either increasing or decreasing in conspicuity 1,2.
Treatment and prognosis
No treatment is required provided that they are recognized as perivascular spaces. Change in the size of the cyst or presence of enhancement should make one doubt the diagnosis. In some instances, particularly those with increasing edema, a biopsy may be required to exclude a tumor. Care must be taken, however, as reactive astrocytosis can be mistaken for a glial tumor leading to further surgery and treatment, especially as the tissue will naturally enough be IDH wildtype.
- 1. Lim AT, Chandra RV, Trost NM et-al. Large anterior temporal Virchow-Robin spaces: unique MR imaging features. Neuroradiology. 2015;57 (5): 491-9. doi:10.1007/s00234-015-1491-y - Pubmed citation
- 2. Rawal S, Croul SE, Willinsky RA et-al. Subcortical cystic lesions within the anterior superior temporal gyrus: a newly recognized characteristic location for dilated perivascular spaces. AJNR Am J Neuroradiol. 2014;35 (2): 317-22. doi:10.3174/ajnr.A3669 - Pubmed citation