Ultrasound for Kidney Stones Detection

Overseen By Ukrit Rompsaithong, M.D.

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of California, San Francisco

Disqualifiers: Pregnancy, Kidney transplantation, Ectopic kidney, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: Surgical duration, up to 4 hours

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests how well ultrasound, a radiation-free imaging method, compares to fluoroscopy, a standard imaging technique, in detecting leftover kidney stone fragments during surgery. The goal is to reduce radiation exposure for patients and healthcare workers while maintaining quality care. The trial seeks participants planning to undergo surgery to remove kidney or ureteral stones. As an unphased trial, it offers a unique opportunity to contribute to advancements in safer imaging techniques.

Do I have to stop taking my current medications for this trial?

The trial protocol does not specify whether you need to stop taking your current medications.

What prior data suggests that ultrasound imaging is safe for detecting kidney stones?

Research has shown that using ultrasound to find kidney stones is generally safe. Studies comparing ultrasound to fluoroscopy (an X-ray imaging method) found both effective, but ultrasound avoids radiation. This makes it a safer choice for patients and healthcare teams concerned about radiation.

Other research on ultrasound for kidney stones indicates that patients tolerate it well, with no serious side effects reported. Although larger stones might risk causing kidney damage, this risk exists with both ultrasound and fluoroscopy.

In summary, ultrasound safely detects kidney stones and carries less risk of radiation exposure compared to traditional methods. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using ultrasound for kidney stone detection because it offers a radiation-free alternative to traditional imaging methods like fluoroscopy. Ultrasound provides real-time imaging, which can help endourologists accurately assess the size of kidney stone fragments during procedures without exposing patients to ionizing radiation. This method could improve the safety and precision of kidney stone management, potentially leading to better outcomes and fewer complications.

What evidence suggests that ultrasound is effective for detecting kidney stones?

Research has shown that ultrasound, one of the methods tested in this trial, can effectively detect kidney stones. Studies have found that kidney stones create a "twinkling effect" on color-Doppler ultrasound, aiding in accurate identification. One study discovered that using ultrasound first reduces radiation exposure compared to CT scans, without missing important diagnoses. Although the twinkling effect alone can sometimes lead to false positives, combining it with endoscopic exams may improve accuracy. This trial will compare ultrasound with the standard method of fluoroscopy, the control arm, to determine the size of the largest residual fragment during retrograde intrarenal surgery. Overall, ultrasound is a promising method for finding kidney stones while minimizing radiation exposure. ^{4 6 7 8 9}

Who Is on the Research Team?

Thomas Chi, M.D.

Principal Investigator

University of California, San Francisco

Are You a Good Fit for This Trial?

This trial is for adults over 18 with diagnosed renal or ureteral stones scheduled for retrograde intrarenal surgery (RIRS). It's not suitable for patients having bilateral stone removal, those who refuse consent, pregnant women, kidney transplant recipients, individuals with ectopic kidneys, or if pain can't be managed in the ER.

Inclusion Criteria

Patients over the age of 18.

Consecutive patients with a diagnosis of renal stone or ureteral stone with a plan to undergoing RIRS for stone removal.

Exclusion Criteria

Patients undergoing concurrent bilateral stone removal surgery.

Patients who decline informed consent.

You are pregnant.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo retrograde intrarenal surgery with either ultrasound or fluoroscopy to detect residual fragments

Surgical duration, up to 4 hours

Follow-up

Participants are monitored for surgical complications and the accuracy of residual fragment detection is assessed

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Ultrasound

Trial Overview The study aims to compare the effectiveness of ultrasound versus traditional fluoroscopy in detecting remaining stone fragments during RIRS. The goal is to reduce radiation exposure and enhance care quality for patients and healthcare teams.

How Is the Trial Designed?

Group I: Ultrasound Experimental Treatment 1 Intervention

Before completing retrograde intrarenal surgery, a complete endoscopic examination will be performed along with ultrasound by the same endourologist to determine the size of the largest residual fragment.

Group II: Fluoroscopy Active Control 1 Intervention

Standard of care, control Before completing retrograde intrarenal surgery, a complete endoscopic examination will be performed along with fluoroscopy by the same endourologist to determine the size of the largest residual fragment.

Ultrasound is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Ultrasound for:

• Kidney stones
• Ureteral stones
• Renal tract disease
• Biliary disease
• Abdominal aortic aneurysm
• Cardiac conditions
• Pregnancy-related conditions

Approved in European Union as Ultrasound for:

• Kidney stones
• Ureteral stones
• Renal tract disease
• Biliary disease
• Abdominal aortic aneurysm
• Cardiac conditions
• Pregnancy-related conditions

Approved in Canada as Ultrasound for:

• Kidney stones
• Ureteral stones
• Renal tract disease
• Biliary disease
• Abdominal aortic aneurysm
• Cardiac conditions
• Pregnancy-related conditions

Who Is Running the Clinical Trial?

University of California, San Francisco

Lead Sponsor

Trials

2,636

Recruited

19,080,000+

Published Research Related to This Trial

In a study of 210 patients with hydronephrosis, urinary stones were identified as the cause in 60% of cases, highlighting their significant role in this condition.

The detection rate of urinary stones increased with the severity of hydronephrosis, with rates of 50% for Grade 1, 61% for Grade 2, and 71.4% for Grade 3, but decreased in Grade 4, indicating a complex relationship between hydronephrosis severity and stone detection.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Association between grades of Hydronephrosis and detection of urinary stones by ultrasound imaging. Alshoabi, SA.[2022]

Sonography has limited effectiveness in detecting renal stones, with sensitivity ranging from 52-57% for the right kidney and only 32-39% for the left kidney, based on evaluations from two radiologists.

The accuracy of sonography for detecting stones was 67% and 77% for the right kidney, but only 53% and 54% for the left kidney, indicating that the detection ability varies significantly depending on which kidney is affected.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Accuracy of sonography for detecting renal stone: comparison with CT. Ulusan, S., Koc, Z., Tokmak, N.[2022]

The study involving 34 subjects and 115 renal stones found that the S-mode ultrasound technique accurately detected 84% of stones identified by CT, with 73% of stone size measurements within 2 mm of CT measurements.

S-mode ultrasound provided better visualization and sizing of kidney stones compared to a standard clinical ultrasound system, with measurements differing from CT by only 1.6 mm for stones and 0.8 mm for shadows, indicating its potential for improved clinical use.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stone-Mode Ultrasound for Determining Renal Stone Size. May, PC., Haider, Y., Dunmire, B., et al.[2019]

Measuring the acoustic shadow behind kidney stones provides a more accurate estimation of their size compared to direct measurements, with an average error of only 0.0 ± 0.8 mm for shadow width across different ultrasound modalities.

Among the ultrasound imaging techniques tested, harmonic imaging was found to be the most accurate for measuring stone size, while the accuracy of stone width measurements decreased with greater imaging depth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Use of the Acoustic Shadow Width to Determine Kidney Stone Size with Ultrasound. Dunmire, B., Harper, JD., Cunitz, BW., et al.[2022]

Ultrasound was able to detect renal stones in 93% of the 83 patients studied, but it only identified all stones in 60% of those cases, indicating some limitations in its accuracy.

KUB with tomograms (KUB/T) proved to be a more reliable method for assessing the size and number of small renal stones, particularly those measuring 2 mm or less, which were often missed by ultrasound.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Role of ultrasound in medical management of patients with renal stone disease. Vrtiska, TJ., Hattery, RR., King, BF., et al.[2022]

In a study of 100 patients, twinkling artifact (TA) on color Doppler ultrasound demonstrated high sensitivity (94%) and accuracy (94%) for detecting kidney stones smaller than 5 mm, making it a reliable diagnostic tool.

TA was found to be significantly more effective than traditional posterior acoustic shadowing in identifying small stones, suggesting that color Doppler ultrasound could serve as a safe alternative to non-contrast-enhanced CT for diagnosing urolithiasis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

An investigation into the clinical accuracy of twinkling artifacts in patients with urolithiasis smaller than 5 mm in comparison with computed tomography scanning. Hanafi, MQ., Fakhrizadeh, A., Jaafaezadeh, E.[2022]

In a study of 77 patients with suspected nephrolithiasis, the presence of hydronephrosis on bedside ultrasound was a strong predictor of hospitalization, with all 13 admitted patients showing hydronephrosis.

Patients with moderate hydronephrosis had a significantly higher admission rate (36%) compared to those with mild hydronephrosis (24%), while none of the patients without hydronephrosis required admission, indicating that hydronephrosis is a critical factor in determining the need for further medical intervention.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The ability of renal ultrasound and ureteral jet evaluation to predict 30-day outcomes in patients with suspected nephrolithiasis. Fields, JM., Fischer, JI., Anderson, KL., et al.[2016]

Ultrasonography (US) demonstrated a sensitivity of 70.0% and specificity of 94.4% for detecting renal stones when compared to noncontrast enhanced computed tomography (NCCT), indicating it is a reliable imaging option.

US was particularly effective in detecting larger stones, with a higher detection rate for stones in other locations compared to the left upper calyx, and showed a strong correlation in size measurements with NCCT in 72% of cases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The efficacy of ultrasonography for the detection of renal stone. Kanno, T., Kubota, M., Sakamoto, H., et al.[2022]

Ultrasound is an effective tool for pre-operative confirmation and localization of kidney stones, offering advantages over X-rays by providing 3D localization and distinguishing between stones and tumors.

In a study involving 44 patients, the ultrasound technique successfully localized stones in 26 cases, demonstrating its potential utility in guiding minimally invasive procedures for stone removal.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Ultrasonic examination in the treatment of renal calculi]. Lytton, B.[2006]

Recent advances in ultrasound technology have improved the diagnosis of urinary stones, utilizing techniques like the twinkling signal and posterior acoustic shadow to enhance detection and sizing of renal stones.

New therapeutic applications, such as ultrasonic propulsion and burst wave lithotripsy, offer noninvasive methods to reposition and fragment stones, demonstrating promising safety and efficacy in various studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Innovations in Ultrasound Technology in the Management of Kidney Stones. Dai, JC., Bailey, MR., Sorensen, MD., et al.[2023]

Ultrasound effectively identified renal stones in nine patients, demonstrating a characteristic 'sonic shadow' that indicates the presence of both opaque and nonopaque stones.

The study highlights the advantages of using gray scale renal ultrasonography as a non-invasive method for evaluating kidney stones, providing clear imaging results.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ultrasonic evaluation of renal calculi. Edell, S., Zegel, H.[2008]

In a study of 209 patients with suspected kidney stones, 52.9% had abnormal ultrasounds indicating the presence of stones or hydronephrosis.

A past history of nephrolithiasis was significantly associated with abnormal ultrasound results, suggesting that ultrasound is particularly justified for patients with a previous history of kidney stones.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical predictors of an abnormal ultrasound in patients presenting with suspected nephrolithiasis. Shafi, ST., Anjum, R., Shafi, T.[2020]

In a study of 31 patients with renal colic, ultrasound demonstrated a high sensitivity of 96.3% in detecting urinary calculi, correctly identifying 26 out of 27 cases confirmed by intravenous urography (IVU).

Ultrasound also showed a perfect specificity of 100%, meaning it accurately ruled out the presence of calculi in cases where none were found, highlighting its effectiveness as a first-line diagnostic tool for renal colic.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Evaluation of the role of echography in the positive diagnosis of renal colic secondary to kidney stone]. Soyer, P., Levesque, M., Lecloirec, A., et al.[2016]

In a study of 116 patients who underwent radical nephrectomy for kidney cancer, renal ultrasound demonstrated varying sensitivity and specificity based on tumor size, with 35% sensitivity for tumors under 2.5 cm and 80% sensitivity for tumors between 2.5 and 7 cm.

While ultrasound is useful as the initial diagnostic tool for staging renal cancer, a CT scan is recommended as the gold standard for accurately assessing solid and cystic lesions, especially for tumors larger than 2.5 cm.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Detection rate of ultrasound vs CT scan in clinical staging accuracy of renal tumors pT1NxMx. Dachille, G., Erinnio, M., Cardo, G., et al.[2016]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4507569/

Improved Detection of Kidney Stones Using an Optimized ... Kidney stones have been shown to exhibit a “twinkling artifact” (TA) under Color-Doppler ultrasound. Although this technique has better specificity than ...

2. sciencedirect.com sciencedirect.com/science/article/pii/S2468227625000882

Detection of kidney stone from ultrasound images using ... The proposed approach of detecting kidney stones using ML algorithms can enhance and improve the diagnosis and detection of kidney stones (renal calculi) from ...

3. nejm.org nejm.org/doi/full/10.1056/NEJMoa1404446

Ultrasonography versus Computed Tomography for ... Initial ultrasonography was associated with lower cumulative radiation exposure than initial CT, without significant differences in high-risk diagnoses.

4. ajronline.org ajronline.org/doi/10.2214/AJR.15.14998

AJR - American Journal of Roentgenology Isolated sonographic twinkling artifact has a high false-positive rate (60%) for the diagnosis of renal calculus in patients without known urolithiasis.

5. 4rai.com 4rai.com/2022/11/01/which-is-better-for-diagnosing-kidney-stones-ct-or-ultrasound/

Which is Better for Diagnosing Kidney Stones, CT or ... The team of researchers found that using an ultrasound first approach did not result in more adverse events, missed diagnoses, or treatment ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6248231/

The role of ultrasonography in detecting urinary tract calculi ... This study was designed to evaluate the accuracy of ultrasonography (US) detection of stones compared to computed tomographic scan as a standard method.

7. sciencedirect.com sciencedirect.com/science/article/pii/S0090429524010720

Efficacy and Safety of Ultrasound- vs Fluoroscopy-Guided ... Larger stones or the use of larger sheaths, for instance, are more likely to cause renal trauma regardless of whether ultrasound or fluoroscopy is used.

8. clinicaltrials.gov clinicaltrials.gov/study/NCT02028559

Safety and Effectiveness of the Ultrasonic Propulsion ... This study tests moving kidney stones using focused ultrasound (referred to as ultrasonic propulsion). The study includes multiple population groups to ...

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4414252/

Focused Ultrasound to Expel Calculi from the Kidney All 26 stones were observed to move during treatment and 17 (65%) were relocated successfully to the renal pelvis (3), ureteropelvic junction (2) or ureter (12) ...