Endolymphatic hydrops in the animal can be produced by various methods. The most promising is obliteration of the endolymphatic duct in the guinea pig. The extent of hydrops is similar to that of Ménière's disease specimens, but the animals are asymptomatic. A better model, utilizing a less invasive method and having the ability to elicit episodic vestibular symptoms, is needed. There is a reasonable doubt that one of the causes for Ménière's disease lies in the abnormal endolymphatic duct and sac. A wide ablation of such pathologic tissue may provide additional pathogenetic information.