Fig. 1

Brain MRI, histopathology and PCR result of case 4. a–c Images were obtained before the operation. Low signal intensity on T1WI, mixed-signal intensity on T2WI, ring, and nodular contrast enhancement (white arrows), with perifocal edema (yellow arrows). d, e MRI reexamined nearly 4 weeks after operation and anti-Toxoplasma therapy. Residual cavity after operation, perifocal edema reduced significantly, lesions resected completely, no recurrence (blue arrows). f Brain lesion at left frontal lobe disappeared (orange arrows). The patient improved clinically and radiographically after 4 weeks of anti-Toxoplasma therapy. g–i Photomicrograph of the histopathological TE, hematoxylin-eosin stained (100×), necrotic center (g), intermediate zone (h), peripheral zone (i) (classical inflammatory response, not contained the encysted form of TG). j The RT-PCR of BML revealed TG-positivity