Bilateral pontine infarction with basilar artery fenestration: A case report.

RATIONALE: Basilar artery (BA) fenestration is a congenital anomaly with duplicated BA, which can cause ischemic stroke. However, the stroke mechanism is not clearly verified in patients with BA fenestration. PATIENT CONCERNS: Here, we report a case of 64-year-old man with well-controlled hypertension admitted with dysarthria, only. DIAGNOSES: Diffusion weighted image showed a bilateral symmetric pontine infarction sparing the midline. BA fenestration was observed from magnetic resonance angiography. INTERVENTION: High-resolution magnetic resonance image (MRI) and 4D flow MRI was performed to verify the mechanism of stroke associated with BA fenestration. OUTCOMES: No plaque was observed at the area of BA fenestration from high-resolution MRI. 4D flow MRI showed bifurcated flow with high flow velocity and low shear stress at the area of BA fenestration. LESSONS: A turbulent flow with high flow velocity and low shear stress at the BA fenestration area may have influenced the flow through the bilateral perforating arteries resulting in a bilateral symmetric pontine infarction with sparing the midline where the septa of BA is located. 4D flow dynamic studies may be beneficial for verifying the mechanism of stroke.