Does Twinkle Artifact on Ultrasound Indicate a Kidney Stone in Pediatric Patients?

Does Twinkle Artifact on Ultrasound Indicate a Kidney Stone in Pediatric Patients? 150 150 Mary Bates, PhD

The presence of twinkle artifact on ultrasound is a useful, though imperfect, tool for diagnosing kidney stones in children.

For pediatric patients, ultrasound is the recommended imaging modality used to diagnose kidney stones. Several findings are used to identify stones on ultrasound, including the presence of an echogenic focus, posterior acoustic shadowing, or twinkle artifact. Twinkle artifact has been shown to be highly predictive of kidney stones in adults, but there are few studies on the predictive value of ultrasound characteristics for diagnosing stones in children.

In a new study published in the Journal of Pediatric Urology, researchers from Nationwide Children’s Hospital evaluated whether twinkle artifact is reliable for diagnosing kidney stones in pediatric patients. The researchers reviewed hundreds of ultrasound reports indicating presence or absence of twinkle artifact in pediatric patients. Presence of a kidney stone was confirmed by computed tomography, visualization on ureteroscopy, or patient-reported passing of the stone.

“We found that in our pediatric population, twinkle artifact may be useful in ruling in the presence of a stone,” says lead author of the study Daniel DaJusta, MD, a urologist at Nationwide Children’s.

Compared to findings in adults, Dr. DaJusta and colleagues found that twinkle artifact in children had lower sensitivity (83%), specificity (78%), and positive predictive value (74%) for detecting kidney stones, while negative predictive value (86%) was similar. The authors say this could be related to kidney location and smaller stone size in pediatric patients.

Overall, Dr. DaJusta and his colleagues conclude that twinkle artifact on ultrasound is a slightly less reliable indication of kidney stones in children than in adults, though it is still a useful finding. Given that ultrasound is the preferred imaging modality for detection of stones in children, they propose combining twinkle artifact with other imaging findings, such as posterior acoustic shadowing and hydronephrosis, to increase the diagnostic specificity.

“The presence of twinkle artifact should be weighed in the setting of other clinical and ultrasound evidence of stones,” says Dr. DaJusta, who is also a clinical assistant professor of urology at The Ohio State University College of Medicine.

“Although twinkle artifact is not a perfect tool for diagnosing kidney stones in children, it is certainly useful and should be assessed for at the time of ultrasound examination, and weighed along with other findings, in these patients.”




Puttmann K, DaJusta D, and Rehfuss AW. Does twinkle artifact truly represent a kidney stone on renal ultrasound? Journal of Pediatric Urology. 30 Mar 2021. [Epub ahead of print] Doi: 10.1016/j.jpurol.2021.03.026.

About the author

Mary a freelance science writer and blogger based in Boston. Her favorite topics include biology, psychology, neuroscience, ecology, and animal behavior. She has a BA in Biology-Psychology with a minor in English from Skidmore College in Saratoga Springs, NY, and a PhD from Brown University, where she researched bat echolocation and bullfrog chorusing.