| The acute stage is characterized by purulence that fills the perilymphatic spaces and spares the endolymphatic space. |
| We report a case of endolymphatic sac tumor in which the patient presented with otalgia and ear discharge. |
| At present, we are unable to differentiate the signal of the endolymph seen in a large endolymphatic sac from perilymph and cerebrospinal fluid. |
| Endolymphatic sac tumor is an uncommon neoplasm arising from the endolymphatic sac or endolymphatic duct. |
| Lymphatic invasion is well-established and pathognomonic for ESS, formerly designated as endolymphatic stromal myosis. |
| The formation of otolith carbonate is an inorganic reaction where calcium carbonate is precipitated from the endolymphatic fluid. |
