Question: A 6 year old female is referred to you for evaluation of a neck mass. She recently started gymnastics classes and noted swelling and pain in the left neck and shoulder when performing handstands. On examination you find a soft, 6 cm mass just behind the sternocleidomastoid muscle. Ultrasound reveals a fluid filled mass without a solid component. Doppler does not reveal prominent supplying vasculature. What is your diagnosis? [Answer will be posted with next week's new question]

Answer to last week's question, "The Voice" (August 15, 2016):

Recurrent respiratory papillomatosis.