Wallerian Degeneration of the Superior Cerebellar Peduncle.

(1000mgat days0 and 14). She continued to experienceworseninglowerextremityweakness.Eventually,shereceived6plasmapheresis treatments withminimal improvement. During the entire periodof follow-up at our center, she required 20 to 30mg daily of oral prednisone. Neurological examination prior to the onset of HiCy therapy revealed symmetrically reduced arm abduction (4−/5) and hip flexion strength (2/5) and her CK level was 2920 U/L. Given progressive muscle weakness in the absence of a robust response to any immunosuppression, shewas treatedwithHiCy, 50mg/kg per day, for 4 consecutive days and supportive care, as previously described.2 Although she developed neutropenic fever 9days later, she recoveredsuccessfully. Shedidnot require red blood cell or platelet transfusion, and her neutropenia ultimately resolved 2 weeks after HiCy dosing. Muscle strength gradually improved to normal, and her CK level decreased to 537 U/L within 7 months of treatment. A repeated magnetic resonance image was performed 21 months after treatment (Figure,B).Her steroidswere taperedoffwithin2yearsofHiCy therapy. At her last visit, she had minimal residual weakness (4+/5deltoids andhip flexors),whichdidnot affect her activitiesofdaily living. Shehas remained inclinical remissionwhile not taking any immunosuppressive therapies, including glucocorticoids,with hermost recent CK level normal at 100U/L 6 years after HiCy treatment.