The Collaborative International Dictionary of English v.0.48:

Gasserian \Gas*se"ri*an\, a.
   Relating to Casserio (L. Gasserius), the discover of the
   Gasserian ganglion.
   [1913 Webster]

   Gasserian ganglion (Anat.), a large ganglion, at the root
      of the trigeminal, or fifth cranial, nerve.
      [1913 Webster]