Figure 2From: Tumefactive multiple sclerosis requiring emergent biopsy and histological investigation to confirm the diagnosis: a case report Uptake of thallium in the lesions on 201 Tl scintigraphy. Definite uptake of thallium is identified in the lesions. However, the retention index (ratio of thallium uptake between late and early phases) is 0.88, suggesting a low possibility of malignancy.Back to article page