Inner ear perfusion: indications and applications.
OBJECTIVE
To examine the indications and applications of inner ear perfusion in the treatment of common otologic diseases, including Meniere disease, sudden sensorineural hearing loss, and autoimmune inner ear disease.


RESULTS
The number of surgical procedures, including vestibular neurectomy, labyrinthectomy, and endolymphatic sac surgery, decreased during the 1990s. Intratympanic gentamicin therapy has become the most frequently performed invasive procedure for treatment of Meniere disease. Reports on successful control of vertigo in patients with Meniere disease have ranged from 71.4 to 100%. There is a correlation between the degree of vestibular ablation in transtympanic gentamicin, the control of vertigo, and the risk of hearing loss. Patients with less than 75% ice-reduced vestibular response had a statistically lower risk of hearing loss, but they had a higher rate of persistent vertigo than patients with 100% reduced vestibular response. One hundred percent reduced vestibular response may not be indicative of complete vestibular ablation and may not be necessary for control of vertigo symptoms. In preliminary studies, inner ear perfusion of methylprednisolone in patients with severe, profound sudden sensorineural hearing loss who fail to respond to standard treatment is beneficial, with improvement in hearing thresholds of 16 to 25 dB and dramatic improvement in speech discrimination scores. No immunosuppressive medication has been found effective in suppressing inner ear inflammatory infiltrates or reducing hearing loss in an animal model.


CONCLUSIONS
Transtympanic chemical perfusion of the inner ear is safe, inexpensive, and easily performed by an otologic surgeon. With inner ear perfusion, high inner ear concentrations of medication can be achieved, and systemic side effects are minimized.
D001327:Autoimmune Diseases / Q000188:drug therapy; D002408:Catheters, Indwelling; D016503:Drug Delivery Systems; D004427:Ear Diseases / Q000188:drug therapy*; D007758:Ear, Inner / Q000187:drug effects*; D003639:Hearing Loss, Sudden / Q000188:drug therapy; D006801:Humans; D008575:Meniere Disease / Q000188:drug therapy; D014432:Tympanic Membrane