Comparison between the eardrop method with tympanostomy tube and intratympanic injection in a rat model.

OBJECTIVE

Medications for middle-ear diseases are commonly delivered into the middle-ear cavity either by the eardrop method with a tympanostomy tube followed by tragal pumping or by intratympanic injection. The solution delivery of the eardrop method was compared with that of intratympanic injection.

METHODS

Thirty rats were used. For the eardrop method, tympanostomy tube insertion, dye solution eardrop application and tragal pumping were performed in one ear. Intratympanic injection of the same solution was performed in the other ear. The ratio of the area stained by the dye solution to the total area of the middle-ear cavity in haematoxylin and eosin-stained temporal bone sections was evaluated.

RESULTS

The stained area ratio was not significantly different between the eardrop method and intratympanic injection (p = 0.897).

CONCLUSION

In our rat model, the eardrop method achieved solution delivery into the middle-ear cavity as effectively as intratympanic injection.