( ( Some stones ) ( ( may ( need ( to ( be ( removed ( by ( surgery ( or ( ultrasound treatments ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT Some) (NNS stones)) (VP (MD may) (VP (VB need) (S (VP (TO to) (VP (VB be) (VP (VBN removed) (PP (IN by) (NP (NN surgery) (CC or) (NN ultrasound) (NNS treatments))))))))) (. .)))
Some stones may need to be removed by surgery or  ultrasound treatments.
(ROOT (S (NP (DT The) (NN option) (S (VP (TO to) (VP (VB remove) (S (NP (NN kidney) (NNS stones)) (ADJP (JJ other) (PP (IN than) (NP (NN surgery))))))))) (VP (VBZ is) (NP (NN ultrasound) (NNS treatments))) (. .)))