BACKGROUND: Osmotic demyelination syndrome (ODS) can be a central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) based on the regions involved even though they share the same disease process, aetiopathogenesis and time course. OBJECTIVES: Present study aims to characterize the clinical, radiological features and the outcome of patients with ODS with movement disorders as the forthcoming manifestation. METHODS: Chart review of patients with ODS with movement disorders. Demographic, clinical and radiological details of the patients were reviewed. RESULTS: Eleven patients (six females; mean age: 48.3 ± 17.6 years) were included in the study. Parkinsonism alone and parkinsonism with dystonia was noted in four patients each (36.4%) while dystonia alone was noted in the other 3 (27.3%). Five patients (45.5%) had postural tremors. While 5 patients had dystonia early in the course of illness (3-7 days), it was delayed (6-9 months) in the other 2. A triphasic course was noted in two patients. The first phase of hyponatremia induced neurological impairment was followed by a second phase of worsening due to the immediate effect of ODS and a third delayed phase of worsening due to delayed effect of ODS. MRI showed both EPM and CPM in eight patients, EPM alone in two patients and CPM alone in 1 patient. Nine patients had a good outcome with mRS < 3. CONCLUSION: Parkinsonism and dystonia are important manifestations of ODS. Triphasic course with a delayed phase of worsening of movement disorders is probably due to the maladaptive neuronal repair. The concept of triphasic ODS is first being described in our series.
BACKGROUND: Osmotic demyelination syndrome (ODS) can be a central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) based on the regions involved even though they share the same disease process, aetiopathogenesis and time course. OBJECTIVES: Present study aims to characterize the clinical, radiological features and the outcome of patients with ODS with movement disorders as the forthcoming manifestation. METHODS: Chart review of patients with ODS with movement disorders. Demographic, clinical and radiological details of the patients were reviewed. RESULTS: Eleven patients (six females; mean age: 48.3 ± 17.6 years) were included in the study. Parkinsonism alone and parkinsonism with dystonia was noted in four patients each (36.4%) while dystonia alone was noted in the other 3 (27.3%). Five patients (45.5%) had postural tremors. While 5 patients had dystonia early in the course of illness (3-7 days), it was delayed (6-9 months) in the other 2. A triphasic course was noted in two patients. The first phase of hyponatremia induced neurological impairment was followed by a second phase of worsening due to the immediate effect of ODS and a third delayed phase of worsening due to delayed effect of ODS. MRI showed both EPM and CPM in eight patients, EPM alone in two patients and CPM alone in 1 patient. Nine patients had a good outcome with mRS < 3. CONCLUSION: Parkinsonism and dystonia are important manifestations of ODS. Triphasic course with a delayed phase of worsening of movement disorders is probably due to the maladaptive neuronal repair. The concept of triphasic ODS is first being described in our series.