{'fraction_non_alphanumeric': 0.024559530165509876, 'fraction_numerical': 0.0202883075280299, 'mean_word_length': 5.02572347266881, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Quantitative assessment of effectiveness of ultrasonic propulsion of kidney stones.

PURPOSE
Ultrasonic propulsion is an investigative modality to non-invasively image and reposition urinary stones. Our goals were to test safety and effectiveness of new acoustic exposure conditions from a new transducer, and to use simultaneous ureteroscopic and ultrasonic observation to quantify stone repositioning.


MATERIALS AND METHODS
During surgery, ultrasonic propulsion was applied transcutaneously while stone targets were visualized ureteroscopically. Exposures were 350 kHz frequency, ≤ 200 W/cm2 focal intensity, and ≤ 3-second bursts per push. Ureteroscope and ultrasound (US) videos were recorded. Video clips with and without stone motion were randomized and scored for motion ≥ 3 mm by independent reviewers blinded to the exposures. Subjects were followed with telephone calls, imaging, and chart review for adverse events.


RESULTS
The investigative treatment was used in 18 subjects and 19 kidneys. A total of sixty-two stone targets were treated ranging in size from a collection of "dust" to 15 mm. Subjects received an average of 17 ± 14 propulsion bursts (per kidney) for a total average exposure time of 40 ± 40 s. Independent reviewers scored at least one stone movement ≥ 3 mm in 18 of 19 kidneys (95%) from the ureteroscope videos and in 15 of 19 kidneys (79%) from the US videos. This difference was likely due to motion out of the US imaging plane. Treatment successfully repositioned stones in two cases that would have otherwise required basket repositioning. No serious adverse events were observed with the device or procedure.


CONCLUSIONS
Ultrasonic propulsion was shown to be safe, and it effectively repositioned stones in 95% of kidneys despite positioning and access restrictions caused by working in an operating room on anesthetized subjects.