Delivering drugs to the cochlea

A German research team have generated the first-ever three-dimensional model of the cochlea for pharmacokinetic calculations.

Physicians often treat damage to the inner ear with intravenous infusions. But very little is known about how much of any drug actually reaches the inner ear, and how it is distributed.

To shed more light on the subject, a research team at the Fraunhofer Institute for Industrial Mathematics ITWM, working with medical experts at the university hospital in Tübingen near Stuttgart, have generated the first-ever three-dimensional model of the cochlea for pharmacokinetic calculations using ANSYS software.

“Using the program, we want to predict the way in which a drug will spread through the patient’s inner ear as a function of the rate at which the medication is applied,” said Stefan Plontke, who leads the project at the hospital’s ENT clinic.

The scientists hope that their model will be accepted for use in drug approval tests too, thus reducing the number of animal experiments. In its present form, it is still relatively simple – it was based on the guinea-pig ear, which has many similarities to the human ear. Their next project is to produce an even more realistic model based on tomographic data.

The researchers are also attempting to develop a one-dimensional model which they hope will enable them to establish the mass transfer coefficient that defines the way in which a drug is distributed through different parts of the cochlea.

“To put it very simply, we try out different values of mass transfer coefficients until the model matches our experimental data,” explained Norbert Siedow, project manager at the Fraunhofer ITWM.