Fig 8. Drawing of the intralabyrinthine perilymph (light gray) and endolymph (dark gray) spaces with indication of ILS extension routes. Intracochlear growth from scala tympani (ST) to scala vestibuli (SV; black arrowheads). ST ends at round window (white arrowheads). Growth from cochlea into vestibule and vice versa through the anatomic open connection between perilymphe in ST and perilymphatic space around the saccule (black arrows). ME indicates middle ear cavity; S, endolymph in saccule, stapes (double black arrowhead); U, endolymph in utricle.