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Year : 2015  |  Volume : 63  |  Issue : 1  |  Page : 124--125

Giant eccentric target sign

Ramakrishna Narra, Suseel Kumar Kamaraju 
 Department of Radiology, Katuri Medical College, Guntur, Andhra Pradesh, India

Correspondence Address:
Dr. Ramakrishna Narra
Department of Radiology, Katuri Medical College, Guntur - 522 019, Andhra Pradesh
India




How to cite this article:
Narra R, Kamaraju SK. Giant eccentric target sign.Neurol India 2015;63:124-125


How to cite this URL:
Narra R, Kamaraju SK. Giant eccentric target sign. Neurol India [serial online] 2015 [cited 2021 Apr 16 ];63:124-125
Available from: https://www.neurologyindia.com/text.asp?2015/63/1/124/152689


Full Text

A 36-year-old woman presented with fever, headache, neck pain, and lethargy for 3 weeks. She had focal seizures with jerking of the left upper limb and twitching of the left half of the face 4 weeks after the onset of illness.

The contrast enhanced MRI showed multiple ring enhancing lesions with eccentric mural nodules (described classically as the eccentric target sign) of varying sizes in both the cerebral hemispheres [Figure 1] and [Figure 2]. Almost all the ring enhancing lesions showed eccentric mural nodules of varying sizes [Figure 3]. The serum was positive for human immunodeficiency virus (HIV)1 and HIV2 and antitoxoplasma antibody IgG was found in the serum. A provisional diagnosis of cerebral toxoplasmosis was considered and pyrimethamine therapy was advocated. Follow-up scan showed resolution of the lesions.{Figure 1}{Figure 2}{Figure 3}

The pathological correlate of this imaging sign has been described as the central enhancing core of the target produced by a leash of inflamed vessels extending down the length of sulcus. This was surrounded by concentric zones of necrosis and a wall composed of histiocytes and proliferating blood vessels with impaired permeability producing the peripheral enhancing rim. [1]

Cerebral toxoplasmosis is one of the most common opportunistic infections in patients having an HIV infection. It closely mimics on MR imaging, central nervous system (CNS) lymphoma, metastasis as well as other granulomatous infections in the brain such as tuberculosis. [2] An early diagnosis is important as immediate and early institution of therapy leads to a better prognosis. However, the sensitivity of the sign is approximately 30%. [3]

References

1Kumar GG, Mahadevan A, Guruprasad AS, Kovoor JM, Satishchandra P, Nath A, et al. Eccentric target sign in cerebral toxoplasmosis: Neuropathological correlate to the imaging feature. J Magn Reson Imaging 2010;31:1469-72.
2Bargalló J, Berenguer J, García Barrionuevo J, Ubeda B, Bargalló N, Cardenal C, et al. The "target sign": Is it a specific sign of CNS tuberculoma? Neuroradiology 1996;38:547-50.
3Ramsey RG, Gean AD: Neuroimaging of AIDS. I. Central nervous system toxoplasmosis. Neuroimaging Clin N Am 1997;7:171-86.