Male, 47 years old, with transient right arm and right leg weakness and numbness. MRI brain:Mild striated restricted diffusion is seen within the left aspect of the pons (image 112 series 506). There may be very subtle corresponding FLAIR hyperintensity though this is equivocal.Elsewhere no restricted diffusion or other significant parenchymal signal abnormality is detected. No parenchymal edema or generalized mass effect is seen. No intracranial hemorrhage or abnormal extra-axial fluid is detected. The ventricular system is normal in size and morphology.MRA brain:No significant intracranial stenosis is seen. In particular, the posterior circulation is within normal limits. Fetal origin of the right PCA is noted. No aneurysms are detected.MRA neck:Conventional aortic branching. No significant vascular stenosis is detected in the carotid circulation by NASCET criteria. Likewise, the vertebral arteries are free of significant stenosis or occlusion.
Mild striated apparent restricted diffusion is seen within the left aspect of the pons. Given the clinical history, this could potentially represent mild pontine ischemia. However, the transverse pontine fibers sometimes produce an artifact which looks similar to this on DWI images. Considering the otherwise normal appearance of the brain, and the normal MRA examinations of the head and neck, the possibility of an artifact should be considered. If clinical suspicion remains high, a follow-up examination can be considered at 1.5T which may decrease the potential for artifact.