Rathke cleft cyst: MR and biomedical analysis of cyst content

J Comput Assist Tomogr. Jan-Feb 1999;23(1):34-8. doi: 10.1097/00004728-199901000-00008.


Purpose: At least one type of Rathke cleft cyst has unique MR findings, specifically, high intensity on T1-weighted images and iso- to low intensity on T2-weighted images relative to white matter. To clarify the influence of cyst content on MR images, we analyzed the cyst content by biomedical methods after surgical removal.

Method: We studied five patients diagnosed with Rathke cleft cyst, whose MR images showed high intensity on T1-weighted images and iso- to low intensity on T2-weighted images. After surgery, total protein and cholesterol levels were quantified, and correlations of protein and cholesterol content with T1 and T2 signal intensities were performed in vitro.

Results: All five cysts had very high concentrations of protein (11,700-26,600 mg/dl, mean 17,940 mg/dl) with nearly no cholesterol (at most 2.0 mg/dl). Along with increases in protein concentration in vitro, the signal intensity of T1-weighted images increased, while that of T2-weighted images decreased. In contrast, the cholesterol concentration sequence influenced the signal intensity of neither T1- nor T2-weighted images.

Conclusion: The unique MR finding of Rathke cleft cysts--high signal intensity on T1-weighted images and low signal intensity on T2-weighted images--might depend mainly on protein concentration, not on cholesterol.

MeSH terms

  • Adult
  • Cholesterol / analysis
  • Craniopharyngioma / chemistry
  • Craniopharyngioma / diagnosis*
  • Female
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Neoplasm Proteins / analysis
  • Pituitary Neoplasms / chemistry
  • Pituitary Neoplasms / diagnosis*


  • Neoplasm Proteins
  • Cholesterol