Twenty-two healthy female volunteers were monitored using electrical impedance tomogprahy (EIT) in two different situations. First, with electrode belt placed over the breast tissue and second, with the electrode belt under the breast tissue. The EIT measurement was performed with adjunct spirometric measurement. The changes of regional ventilation related to the breast tissue and the size of breast tissue were evaluated.

The EIT measurement (PulmoVista 500, Dräger Medical, Germany) was performed in supine lying position. On every subject, an electrode belt of proper size based on the measured thorax circumference was placed. It was crucial to find a right position where it was possible to place the electrode belt over the breast tissue and then underneath the breast tissue, without changing the level and the position of the electrode belt on the thorax. Also, the position of the belt had to be between 4th and 6th intercostal space, as recommended by the manufacturer. The change of the position of the belt relative to the breast tissue was performed in a lying position by a slight pull of the buckled belt away from the subject´s body, so the subject could relocate the breast tissue over the belt using her own hands into the position as desired by the researcher.

Inclusion Criteria:

• healthy female volunteers

Exclusion Criteria:

• morbid obesity
• standard exclusion criteria for electrical impedance tomography according to the manufacturer

The eligibility is based on natural physical differences of the female anatomy.