A pontine stroke is a stroke that occurs in the pons, which is a portion of the brain stem. The pons is located between the midbrain and medulla. Its function is to relay messages between the cerebral hemispheres and cerebellum.
Strokes in the brain stem have complicated symptoms and can be difficult to diagnose, based on information from the American Stroke Association. Patients can experience double vision, dizziness, vertigo, slurred speech and imbalance. Since the brain stem controls breathing, blood pressure and consciousness, a stroke in this area can impair any of these functions. In severe cases, patients can experience locked-in syndrome and can only move their eyes. Risk factors for pontine strokes include heart disease, diabetes, high blood pressure and smoking.