The Collaborative International Dictionary of English v.0.48:

Optocoele \Op"to*coele\, Optocoelia \Op`to*coe"li*a\, n. [NL.
   optocoelia, fr. Gr. ? optic + koi^los a hollow.] (Anat.)
   The cavity of one of the optic lobes of the brain in many
   animals. --B. G. Wilder.
   [1913 Webster]