Drug Delivery Through Eustachian Tube vs Intratympanic

@kelpiemsp @Aaron123 @JohnAdams @Dr. Ancill @Dr. Jay Hobbs

I've been wondering why we can't deliver drugs to the middle ear through the eustachian tube. ET is listed as a drain-off for drugs that are delivered through the ear drum, so clearly there is a path down, but why can't we use it as a path "up", like a tiny tube, to reach the middle ear and deliver the drugs there?

I did read up research papers describing middle ear surgery through the ET (I think it was a stapedotomy), so we are able to stick in a few surgical instruments (it is tight though), so why not a drug delivery "tube"?

 

Drug delivery is out of my scope and experience, but it seems reasonable to me. I suspect visualization and patient preparation (d/t gagging) would be added challenges that make that method less desirable as compared to the potential complications of penetrating the ear drum.

 

Delivery of drugs to the middle ear via the Eustachian tube.

The medication reduces tubal edema, improving ventilation of the middle ear. Administration of metered dose surfactant (with or without steroids) has shown a reduction in opening pressure of the Eustachian tube. Intranasal drug delivery to treat the middle ear, however, is not widely used clinically. This is because it is technique dependent and requires drug passage through the nasal vestibule, hence the dose of drug delivered may vary. The Eustachian tube orifice can also be identified endoscopically and cannulated to facilitate drugs targeted to the middle ear. This requires navigation using fibre-optic...

Hoskison, Daniel, Al-Zahid, Shakesheff, Bayston & Birchall
Therapeutic Delivery
(2013) 4(1)
120
future science group

There's many other medical journal discussions on this and the ones that I reviewed are very long reads.