Eccentric target sign (cerebral toxoplasmosis)

Eccentric
target sign (cerebral toxoplasmosis) • Cerebral toxoplasmosis - Ganzer Fall bei Radiopaedia
Hanh, L. Cerebral toxoplasmosis. Case study, Radiopaedia.org. (accessed on 02 Nov 2022) https://doi.org/10.53347/rID-85779 • CC by-nc-sa 3.0 (modified)
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The eccentric target sign is considered pathognomonic for cerebral toxoplasmosis. It is seen on postcontrast MRI/CT as a ring enhancing lesion with an eccentrically located enhancing mural nodule. It is believed that this mural nodule is an extension from the abscess wall itself with inflamed vessels in its groove. The sign is seen in less than one-third of cases and hence is not very sensitive.