Routine blood tests revealed glycosylated haemoglobin of 7.4%. An urgent MRI scan of his brain was requested showing increased signal in the right caudate nucleus and right temporal lobe and bilateral 3rd nerve thickening along with meningeal enhancement (). MRI of the spinal cord was normal. A right sided relative pupil-sparing third nerve palsy was diagnosed. Other routine blood tests, including biochemical profile, blood count, coagulation screen, thyroid function, vasculitis screen, tumour markers, angiotensin converting enzyme, creatine kinase and inflammatory indices were normal or negative. Neuronal antibodies were negative.
Figure 1 (A) Initial transaxial T2 image demonstrating high signal abnormality in the right caudate nucleus. (B) Initial coronal FLAIR section also showing infiltration within the medial aspect of the right temporal lobe. (C) Contrast enhanced T1 MRI 3 weeks after (more ...)
Cerebrospinal fluid (CSF) examination (normal values in parenthesis) revealed a normal opening pressure, glucose and lactate dehydrogenase with a protein of 0.78 g/l (0.2–0.5 g/l), 4 lymphocytes (<5) and 150 red cells. The same oligoclonal bands were detected in both serum and CSF. The sample was unsuitable for cytological diagnosis. A CT of the thorax, abdomen and pelvis demonstrated a single 4 mm nodule in the peripheral right upper lobe of unknown clinical significance. A repeat MRI brain after 3 weeks demonstrated disease progression, with thickening of both third nerves and adjacent meninges ().