Medial medullary infarction with restricted sensory symptom.

Sensory abnormalities in patients with medial medullary infarction (MMI) usually involve half of the patient's body and extremities. We report 3 patients with restricted sensory symptoms due to MMI. Patient 1 had sensory symptoms restricted to the contralateral foot secondary to an infarct selectively involving the ventral portion of the medial lemniscus that probably corresponds to leg-representing area. Patient 2 had restricted sensory changes over the contralateral perioral area caused by lesions predominantly involving the posterior part of the medulla that may have affected a part of the ascending trigeminal tract. Patient 3 had sensory symptoms limited to the upper part of his body and the arms (pseudosyringomyelia pattern) due to bilateral MMI that may have resulted from the ventral-dorsal difference in the severity of the lesion. These patients illustrate that restricted sensory abnormalities can occur in patients with MMI. Our MRI-clinical correlation study is consistent with the previously reported sensory topography of the medial lemniscus and the ascending trigeminal tract: the leg-representing area is located ventrally in the medial lemniscus whereas the perioral-representing area is situated most medially in the ascending trigeminal tract.