Hypertrophic Cranial Pachymeningitis With IgG4-Positive Plasma Cells Detected by C-11 Methionine PET

A 53-year-old man who presented with mild headache and ophthalmodynia underwent carbon-11 methionine (MET) positron emission tomography (PET). MET PET images demonstrated intense uptake in the periphery of the brain, significantly higher than the physiological uptake in the brain. Biopsy specimens from the pachymeninx indicated hypertrophic pachymeningitis with IgG4-positive plasma cells. After steroid therapy, he became asymptomatic, and a...