Abstract
We repeatedly performed 1H-magnetic resonance spectroscopy in the right parietal lobe of 7 patients with West syndrome who were treated with ACTH and analyzed the influence of ACTH therapy on metabolism.
ACTH-Zn (0.015mg/kg) was injected intramuscularly every day for the first 2 weeks and was gradually decreased thereafter over six weeks. NAA/Cr ratios were decreased in all 7 patients one month after the initiation of ACTH therapy. The extent of this decrease was remarkable in patients who were younger than 12 months of age. NAA/Cr ratios almost returned to their former values 4 months after the end of ACTH therapy, but remained low in 2 patients who were both younger than 12 months of age. Cho/Cr ratios were decreased in all 5 patients younger than 12 months of age at one month after the initiation of ACTH therapy and returned to their former values 4 months after the end of ACTH therapy. No remarkable change in Cho/Cr ratios was recognized in 2 patients older than 12 months of age. These findings suggest that ACTH decreases NAA synthesis in neurons and that ACTH may induce irreversible neuronal loss. Furthermore, ACTH may also suppress myelination. These potential actions of ACTH appear to be greatest in patients younger than 12 months of age.
