Teaching NeuroImage: Cervical Radiculopathy Due to Vertebral Artery Dissection

A 40-year-old woman presented with a 3-week history of nonradiating left-sided cervical pain, followed by a 3-day history of left upper limb weakness (affecting shoulder abduction, external rotation, and elbow flexion).Electromyography revealed deltoid muscle denervation, indicating possible subacute C5 radiculopathy.Weakness with cervical pain raised concern for a cervical spine abnormality, prompting an unremarkable initial MRI.However, neck pain persisted, and eco-color Doppler revealed decreased flow in the left vertebral artery, suggesting vertebral artery dissection (VAD).Dedicated T1 fat-saturated (Figures 1A and2A) and gradient-echo (Figure 1B) sequences showed a mural hematoma compressing the C5 nerve root.MR angiography confirmed a nonocclusive VAD at the extradural segment (Figure 2B).The patient showed clinical and radiologic improvement after 6 months of single antiplatelet therapy (Figure 2, C andD).VAD-related radiculopathy is rare but should be considered in unexplained causes of acute neck pain.Possible mechanisms include compression from a mural hematoma or impaired vasa nervorum perfusion, with the C5 nerve root being especially vulnerable. 1,2 Axial T1 fat-saturated (fs) sequence at the level of C4-C5 (A) shows eccentric crescent-shaped hyperintense subacute intramural hematoma of the left vertebral artery (VA) extradural segment (white arrowhead), consistent with vertebral artery dissection, compressing the C5 nerve root (yellow arrow) on axial gradient-echo T2-weighted sequence (B).