[1] Departments of Phoniatrics and Otorhinolaryngology,
[2] Institute of Phoniatrics,undefined
[3] University Medical Centre Utrecht,undefined
[4] Heidelberglaan 100,undefined
[5] 3438 CX Utrecht,undefined
[6] The Netherlands Tel.: +31-30-2508890,undefined
[7] Fax: +31-30-2541922,undefined
[8] Department of Physiology,undefined
[9] Université Catholique de Louvain,undefined
[10] Brussels,undefined
[11] Belgium,undefined