Central pontine myelinolysis and pontine lesions after rapid correction of hyponatremia: A prospective magnetic resonance imaging study

The rate at which profound hyponatremia should be corrected is the focus of a recent clinical debate. We prospectively studied neurological outcomes with serial magnetic resonanace imaging in 13 hyponatremic subjects with serum sodium concentrations of less than 115 mmol/L (mean initial serum sodium concentration, 103.7; range, 93–113 mmol/L). All subjects were corrected to mildly hyponatremic levels at 24 hours and ultimately underwent an increase in serum sodium concentration of 25 mmol/L without development of hypernatremia. Magnetic resonance imaging revealed the development of pontine lesions in 3 patients. The correction rate of hyponatremia over the first 24 hours was significantly faster in patients with pontine lesions (mean ± SD, 1.25 ± 0.4 mmol/(L ± hr) versus 0.74 ± 0.3 mmol/(L ± hr); ±