Open ring sign
Citation, DOI & article data
The enhancing component is thought to represent advancing front of demyelination and thus favors the white matter side of the lesion. The open part of the ring will therefore usually point towards the grey matter 3.
Treatment and prognosis
Often patients with such lesions undergo biopsy, where the histology can be difficult to interpret. Abundant bizarre astrocytes with frequent mitoses can suggest the diagnosis of glioblastoma. Toxoplasmosis may also be suggested by the presence of giant cells (Creutzfeldt cells).
As such, careful assessment of imaging is essential to avoid unnecessary and misleading intervention.
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