Drug delivery from the middle ear to the inner ear for the treatment of inner ear diseases such as sensorineural deafness can significantly reduce systemic side effects due to the highly selective and low dosage of the drug, and nanomedicine carriers can further improve the therapeutic effect of conventional drugs due to their controllability and targeting. Zou Jing et al. investigated the molecular mechanism of Ras GTPases regulating cochlear blood-endolymph barrier structural proteins and p-glycoprotein through the European Union Nano-Ear (NMP4-CT-2006-026556) and the National Natural Science Foundation of China (81170914/H1304), injecting different nanoscale liposomes (95 nm, 130 nm, 240 nm) into the middle ear of rats and then injecting them into the middle ear. Liposomes of different nanoscale (95 nm, 130 nm, 240 nm) were injected into the middle ear of rats and tracked in vivo by means of high-resolution magnetic resonance imaging. It was found that 95 nm liposomes had the highest efficiency of uptake in the inner ear, and 240 nm liposomes had the lowest efficiency of uptake in the inner ear (Figs. 2 and 3). The Finnish group and the Changhai Hospital group are exploring highly selective drug delivery strategies in the inner ear, which is expected to bring benefits to deaf patients. Figure 1. Dynamic uptake in the inner ear after injection of nanoliposomes via the middle ear. At 3 hours post-injection, nanoliposomes were detected in the vestibule (A) and cochlea (B). Uptake increased in the vestibule (C) and cochlea (D) 6 h after injection. apex: cochlear tip; 2nd: cochlear second gyrus; 1st: cochlear fundal gyrus. st: cochlear tympanic order; SV: cochlea vestibular order; ME: middle ear; vest: vestibule. 3h: 3 h; 6h: 6 h. Fig. 2. Scale-dependent transport efficiency of nanoliposomes passing through the middle ear to the inner ear. Horizontal coordinates are different parts of the inner ear and vertical coordinates are the transport efficiency.