To report a stroke case of bilateral medial medullary syndrome (MMS) with atypical clinical presentations

MMS is an uncommon brainstem syndrome. Patients usually have contralateral hemiparesis with cranial nerve palsies. Bilateral MMS (bMMS) is even more rare with about 40 cases reported. We report a bMMS stroke case that presented with hemiparesis, urinary retention and constipation without cranial nerve palsy. To our knowledge this is the first case report where bMMS mimics as a spinal cord disorder

This case report describes a bMMS stroke mimicking a spinal cord disorder

Healthy 36 year-old Caucasian male presented with a two-day history of left side weakness after he was stung by a tick. Initial neurological examination revealed asymmetric quadriparesis with intact cranial nerves and sensation. Strength was 2/5 on the left extremities and 4/5 on the right. Muscle tone was increased. MRI brain and CT Angiography (CTA) of head and neck were reported normal. Patient was admitted for further spinal cord disorder workup. MRI spines were normal. Next day, he developed hypophonia, dysphagia, dysarthria, respiratory distress, and became quadriplegic. His cranial nerves II-VIII and XI-XII were still intact. He had nystagmus and decreased sensation on the left. He was intubated and a repeat MRI brain showed a “heart sign” infarction in the rostral bilateral medial medulla. Initial MRI and CTA were reviewed again. It was determined that the right V3-4 segment had a dissection. There were hyperintense changes in the ventral medial medullar on DWI but without correlating ADC or Flair changes. The cause of stroke was thought to be a spontaneous right vertebral dissection.

bMMS is a very rare stroke syndrome that can be misdiagnosed when symptoms are atypical and MRI does not show acute infarction. Detailed neurological examination and a careful review of neuroimaging is helpful to make the diagnosis.