Diane R. Bielenberg1,3 and Patricia A. D'Amore2,3 1Boston Children's Hospital, Boston, Massachusetts 02115, USA 2Massachusetts Eye & Ear, Boston, Massachusetts 02114, USA 3Harvard Medical School, Boston, Massachusetts 02115, USA Correspondence: diane.bielenberg{at}childrens.harvard.edu; patricia_damore{at}meei.harvard.edu