PURPOSE: To document the changes observed at sequential magnetic resonance
(MR) imaging of sarcoidosis lesions of the central nervous system (CNS) dur
ing treatment with corticosteroids.
MATERIALS AND METHODS: The abnormalities detected in 24 patients (mean foll
ow-up, 36 months) were compared before and after therapeutic periods (n = 7
5) that were divided into attack (high-dose), upkeep (decreased-dose), and
minimal (low-dose) periods. Parenchymal lesions were classified as type 1 (
enhanced with gadolinium), type 2 (demyelinating), or type 3 (lacunar) and
were assessed as regressing, stable, or progressing.
RESULTS: Seven of the 24 patients had several types of lesions. Isolated ty
pe 3 lesions (six patients) were the only lesions not associated with neuro
logic deficit. Type 1 lesions (13 patients) regressed in 22 of 22 attack pe
riods and progressed in nine of 27 upkeep and minimal periods. MR imaging d
epicted relapses in patients with multifocal CNS involvement or long-standi
ng CNS impairment or in those who had previously received steroid therapy.
Type 2 (seven patients) and type 3 (13 patients) lesions remained stable in
68 of 68 therapeutic periods. Type 1 lesions appeared in three patients wi
th type 2 and type 3 lesions during two upkeep and three minimal periods. F
indings at follow-up MR imaging contributed to the reintroduction of high-d
ose corticosteroid therapy in eight patients.
CONCLUSION: MR imaging can be used to differentiate between reversible and
irreversible lesions in CNS sarcoidosis. MR imaging can be a useful tool fo
r adjusting treatment to prevent irreversible CNS damage.