Overview of the cochlear structure and the site of cisplatin absorption

This illustration depicts the anatomical structure of the cochlea, highlighting the various cell types vulnerable to cisplatin-induced damage. The cochlea consists of three fluid-filled compartments: the scala vestibuli and scala tympani, filled with Na⁺-rich perilymph, and the scala media, filled with K⁺-rich endolymph. The scala media houses the organ of Corti, which comprises the inner hair cells (responsible for auditory transduction), outer hair cells (critical for cochlear amplification), and surrounding supporting cells. Adjacent to the organ of Corti sits the lateral wall, comprising the stria vascularis (responsible for generating and maintaining the endocochlear potential, the driving force for sensory transduction) and spiral ligament (supporting the stria vascularis and cochlear fluid homeostasis). Spiral ganglion neurons innervate the sensory hair cells and transmit auditory signals to the auditory nuclei in the brainstem. Cisplatin enters the endolymph in the scala media through capillaries in the stria vascularis and is subsequently absorbed by the sensory hair cells in the organ of Corti (red dashed arrows). (Source: Tan WJ, Vlajkovic SM. Molecular characteristics of cisplatin-induced ototoxicity and therapeutic interventions. Int J Mol Sci 2023;24[22]:16545. Creative Commons Attribution 4.0 International [CC BY 4.0] license, creativecommons.org/licenses/by/4.0.)