Related Experiment Video
Updated: Jun 14, 2026
09:18
A Comparative Study of Drug Delivery Methods Targeted to the Mouse Inner Ear: Bullostomy Versus Transtympanic Injection
Published on: March 8, 2017
Enhancing Round Window Membrane Permeability for Inner Ear Drug Delivery: A Systematic Review
Agathe Bedoux1,2, Pauline Ropero3, Yohan Bouleau4
1Univ. Bordeaux, INSERM, BioTis, U1026, Bordeaux, France.
Tissue Engineering. Part B, Reviews
|June 13, 2026
Summary
This review explores methods to improve drug delivery to the inner ear for sensorineural hearing loss. New biomechanical and biochemical strategies show promise for enhanced treatment efficacy.
Area of Science:
- Otorhinolaryngology
- Biomedical Engineering
- Pharmacology
Background:
- Sensorineural hearing loss is a significant public health issue with limited treatment options.
- The cochlea's complex anatomy and biological barriers, particularly the round window membrane (RWM), hinder effective drug delivery.
- Intratympanic injection's passive diffusion is often inadequate for large or hydrophilic molecules like gene therapy vectors.
Purpose of the Study:
- To systematically review biomechanical and biochemical strategies for enhancing RWM permeability.
- To evaluate methods for improving drug delivery efficiency and targeting to the inner ear.
- To identify strategies that modulate RWM properties or indirectly enhance drug delivery.
Main Methods:
- Conducted a systematic literature search following PRISMA guidelines across Scopus, MEDLINE/PubMed, Cochrane, and CINAHL.
- Included *in vivo* studies and clinical trials investigating biochemical or biomechanical RWM enhancement strategies.
- Assessed risk of bias using the SYRCLE tool; 89 articles met inclusion criteria from 1776 screened.
Main Results:
- Identified four biochemical approaches (hydrogels, nanosystems, microsystems, permeabilizers) and three biomechanical strategies (sonoporation, acoustic stimulation, magnetic systems).
- Most reviewed strategies demonstrated improved inner ear drug delivery or therapeutic outcomes.
- Recent research increasingly focuses on advanced methods like nanosystems and sonoporation for larger molecules, including gene therapy.
Conclusions:
- Various biochemical and biomechanical strategies effectively enhance RWM permeability for inner ear drug delivery in preclinical models.
- A shift towards advanced delivery systems is observed, targeting larger molecules like gene therapy vectors.
- Further research is crucial for the clinical translation of these promising drug delivery methods.
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