Left arm and face weakness. Assess for stroke. There is restricted diffusion in the mesial dorsal pons where there is also increased T2 signal compatible with an acute to subacute infarct. Scattered foci of T2 hyperintensity in the periventricular and subcortical white matter compatible with chronic small vessel ischemic changes. This is associated with a small right thalamic and right corona radiata chronic lacunar infarcts. Note is made of a prominent perivascular space in the left insula. There is no evidence of intracranial hemorrhage, mass or edema. The ventricles and basal cisterns are normal in size and configuration. The paranasal sinuses are clear. The visualized mastoid air cells are clear. The orbits are unremarkable. Note is made of a 13 mm ovoid lesion in the subcutaneous tissues overlying the left zygoma compatible with sebaceous cyst.MRA head:The intracranial carotid arteries demonstrate mild atherosclerotic irregularity. The PCOM arteries are diminutive bilaterally. The V4 segment of the right vertebral artery is completely occluded from the level of the arch of C1. No significant intracranial aneurysm. MRA neck:Conventional arch anatomy. The carotid arteries are widely patent with normal contour and caliber throughout. The left vertebral artery is moderately stenotic at its origin but returns to a normal caliber and contour for the remainder of its course. The right vertebral artery is markedly narrowed and irregular throughout with complete occlusion of its intracranial portion. This is compatible with a dissection of indeterminate age. There is a subcutaneous lipoma incidentally noted in the right posterior paraspinal soft tissues.
1. Acute to subacute infarct involving the mesial dorsal pons.2. The right vertebral artery is markedly narrowed and irregular throughout with complete occlusion of its intracranial portion. This is compatible with a dissection of indeterminate age.3. Moderate stenosis of the origin of the left vertebral artery which is otherwise normal in caliber and contour. Mild atherosclerotic irregularity of the intracranial internal carotid arteries.4. Chronic white matter small vessel ischemic changes as well as chronic lacunar infarcts in the right thalamus and right corona radiata.