FIG 2. Patient 2, a 22-year-old woman who was admitted to the hospital for sudden left pyramidal weakness and paresthesia.

A, Fast fluid-attenuated inversion recovery image (9000/110/2 [TR/TE/NEX]; inversion time, 2200 ms) obtained 24 hr after symptom onset. Symptomatic high-signal-intensity lesion is identified in right deep white matter.

B, Contrast-enhanced T1-weighted image (600/15/2) obtained 24 hr after symptom onset. Symptomatic high-signal-intensity lesion shows slight peripheral enhancement.

C, ADC map obtained 24 hr after symptom onset. Symptomatic high-signal-intensity lesion shows marked signal drop compared with contralateral normal appearing white matter.

D, Initial proton spectrum (spin-echo, 1600/135). Lesion shows slight NAA decrease and excess of lactate (Lac). Cho indicates choline.

E, Fast fluid-attenuated inversion recovery image obtained 90 days after symptom onset. Symptomatic right lesion is slightly smaller as compared with initial examination. In addition, a new lesion appeared on the left parietal white matter.

F, Contrast-enhanced T1-weighted image obtained 90 days after symptom onset. Contrast material uptake is observed only in the new lesion.

G, ADC map obtained 90 days after symptom onset. Initial lesion is hyperintense compared with contralateral normal appearing white matter.

H, Final proton spectrum obtained 90 days after symptom onset. Symptomatic lesion shows reduced NAA signal, increased Cho signal, and absence of lactate.