الفهرس 
Anatomy of intra-tympanic injection pathwayOnly 14 pages are availabe for public view
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Abstract
Many inner ear disorders such as sudden sensori-neural hearing loss, Ménière’s disease, autoimmune inner ear disease and tinnitus cannot be adequately treated by systemic drug delivery.
The clinical usefulness, however, is limited by undesirable side effects of these drugs arising from the high systemic doses required to achieve therapeutic concentration in the cochlea (Erin et al., 2008).
Several methods are available which include direct intra-tympanic perfusion into the middle ear and Micro-Catheters or Micro-Wicks which are placed against the round window (Plontke et al., 2006). Intra-tympanic delivery can be accomplished via perfusion of the middle ear with the goal of diffusion through the round window membrane into the fluid spaces of the inner ear (Erin et al., 2008).
The main advantages of intra-tympanic therapy are the ease of administration, avoidance of surgery, alternative therapy when systemic route is contra-indicated or poorly tolerated, and possible salvage therapy when systemic therapy fails (Doyle et al., 2004).
Advantages of Intra-tympanic steroid therapy: Intra-tympanic steroid perfusion has the advantages of avoiding the systemic side effects associated with oral corticosteroids and delivering high concentrations to the inner ear end organ. Steroids delivered by the intra-tympanic route demonstrate higher concentrations in the perilymph than those administered intravenously. The best profile has been reported for methylprednisolone (Parnes et al., 1999).