Central Pontine Myelinolysis Medical Slides

Emphasize the prevention-focused approach: correct sodium by ≤8 mEq/L in 24 hours (some guidelines allow ≤10 in low-risk, but ≤6 in high-risk patients — alcoholism, malnutrition, hypokalemia, Na <105). Teach frequent monitoring: serum sodium every 2-4 hours initially. If overcorrection occurs (>10 mEq/L), immediately administer DDAVP 2-4 mcg IV + D5W to re-lower sodium back to the safe range ("re-lowering protocol"). This rescue strategy can prevent ODS if applied within 24 hours of overcorrection.

Present the characteristic biphasic course: initial neurological improvement as hyponatremia corrects (days 1-3), followed by delayed deterioration at 2-7 days with dysarthria, dysphagia, quadriparesis, and "locked-in syndrome" in severe cases. Extrapontine involvement adds movement disorders (parkinsonism, dystonia, mutism). This biphasic pattern is the key teaching point — clinicians must maintain high suspicion even after initial clinical improvement and obtain MRI if delayed symptoms emerge.

Emphasize the critical teaching point that MRI may be normal in the first 1-2 weeks despite clinical symptoms. T2/FLAIR shows the classic pontine "trident" or "bat-wing" hyperintensity, and DWI may show restricted diffusion earlier (within days). A normal MRI does not exclude ODS if obtained early — repeat imaging at 2-4 weeks is recommended if clinical suspicion persists. This prevents premature diagnostic reassurance based on early negative imaging.