Central pontine myelinolysis: Delayed changes on neuroimaging

The authors report two cases, a 44-year-old woman and a 6-year-old girl who had mental status changes and hyponatremia. Serum sodium levels in both of these cases were corrected quickly with further decline in their mental st atus, and the patients became quadriparetic. Magnetic resonance imaging (MR I) studies performed then did not reveal any abnormalities, whereas a repea t imaging study performed 10-14 days after the shift in serum sodium reveal ed evidence for central pontine myelinolysis and extrapontine demyelination . The clinical manifestations and distribution of lesions seen on the imagi ng studies demonstrated that the above presentation of neurologic illness i s the result of hyponatremia and its correction. The authors conclude that imaging studies performed early during the illness may be unremarkable, but still a diagnosis of central pontine myelinolysis should be suspected and, most importantly, a repeat imaging study might be required in 10-14 days t o establish the diagnosis of central pontine myelinolysis.