Figure 6.

Lymphomatosis cerebri in an immunocompetent patient. An axial fluid-attenuated inversion recovery image (A) shows unspecific diffuse hyperintense areas on both brain hemispheres that cross the splenium of the corpus callosum with no mass effect. No contrast enhancement was observed (not shown). A comparative fluid-attenuated inversion recovery image (B) was obtained after two months without specific therapy confirming the extensive progression of the disease, and exhibiting confluent hyperintensity of both brain hemispheres, predominantly of the left. Minimal mass effect and no gadolinium-enhanced areas were observed. A proton magnetic resonance spectroscopy study (C) was useful to support a presumptive diagnosis and demonstrated increased choline levels and an increased choline/N-acetylaspartate ratio (>1.9), which were associated with reduced N-acetylaspartate levels and elevated lactate peaks.