( ( Treatment options ) ( Surgery ( ( ( was once ) ( ( the ( only option ) ) ( when ( ( kidney stones ) ( became ( stuck ( in ( the ureter ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NNP Treatment) (NNS options)) (ADVP (RB Surgery)) (VP (VBD was) (ADVP (RB once)) (NP (NP (DT the) (JJ only) (NN option)) (SBAR (WHADVP (WRB when)) (S (NP (NN kidney) (NNS stones)) (VP (VBD became) (VP (VBN stuck) (PP (IN in) (NP (DT the) (NN ureter))))))))) (. .)))
Treatment options Surgery was once the only option when kidney stones became stuck in the ureter.
(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))) (. .)))