Can Doppler ultrasonography twinkling artifact be used as an alternative imaging modality to non-contrast-enhanced computed tomography in patients with ureteral stones? A prospective clinical study

Exploring the potential of combined B-mode features and color Doppler ultrasound in the diagnosis of ureteric stone as an alternative to ionizing radiation exposure by computed tomography

OBJECTIVE

To assess the diagnostic efficacy of integrating B-mode and color Doppler capabilities of ultrasound (US) to establish a robust standalone diagnostic tool for the diagnosis of ureteric stones as an alternative to non-contrast-enhanced computed tomography (NCCT).

METHODS

A total of 140 consecutive patients diagnosed with ureteric stones using NCCT were enrolled. On the same day, US in both B-mode and Color Doppler was performed by an experienced radiologist who was blinded to the NCCT scan results. The diagnostic rate of US for stone detection was recorded. Additionally, baseline patient and stone characteristics were analyzed for their association with the accuracy of stone detection using US.

RESULTS

US exhibited a high sensitivity of 91.43%, detecting 128 out of 140 stone foci. Notably, ureteric stones in the proximal and uretero-vesical junction (UVJ) segments were readily identifiable compared to those in the pelvic region (p = 0.0003). Additionally, hydronephrosis enhanced the US's ability to detect stones (p < 0.0001). Conversely, abdominal gases and obesity adversely affected US capabilities (p < 0.0001 and p = 0.009, respectively). Stone side, size, and density showed no statistically significant impact (p > 0.05).

CONCLUSIONS

US with its color Doppler capabilities could serve as a reliable and safe alternative imaging modality in the diagnostic work up of patients with ureterolithiasis. Factors including stone location, Hydronephrosis, weight and abdominal gases significantly influenced its accuracy.

Diagnostic accuracy of Doppler twinkling artifact for identifying urolithiasis: a systematic review and meta-analysis

OBJECTIVE

The goal of this study was to perform a comprehensive meta-analysis to assess the overall diagnostic value of Doppler twinkling for the diagnosis of urolithiasis.

METHODS

We systematically searched the PubMed, EMBASE, and Cochrane Library databases from inception through May 31, 2021. Studies including patients with urolithiasis who underwent color flow Doppler sampling to highlight the twinkling artifact and computed tomography were included. Diagnostic test meta-analysis was performed with a bivariate model. We used summary receiver operating characteristic curves to summarize the overall diagnostic performance. The weighted sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were calculated.

RESULTS

Sixteen studies involving 4572 patients were included in the systematic review and meta-analysis. The weighted sensitivity was 0.86 (95% confidence interval [CI] 0.72-0.94), specificity 0.92 (95% CI 0.75-0.98), positive likelihood ratio 11.3, negative likelihood ratio 0.2, and diagnostic odds ratio 75.5.

CONCLUSION

The Doppler twinkling artifact has good diagnostic value for the diagnosis of urolithiasis and should be used as a complementary tool in the diagnosis of urolithiasis.

Value of the color Doppler imaging mode in improving physicians' diagnostic performance in patients with mid-ureteric stones larger than 5 mm: a retrospective study

The aim of this study was to retrospectively evaluate the value of the color Doppler flow imaging mode compared to the gray-scale mode for diagnosing mid-ureteric stones larger than 5 mm. We consecutively collected images from 79 patients possibly suffering from mid-ureteric stones under gray-scale and color Doppler flow imaging modes. Using computed tomography as the gold standard, all the included images were reviewed in a blinded manner for the confirmation of ureteral stones by 15 physicians divided into three groups according to their clinical experience level (resident, attending, and senior). During the evaluation process, the evaluation consistency was calculated and compared using Kendall's coefficient of concordance (Kendall's W). Moreover, diagnostic performance considering gray-scale and color imaging modes was compared. Especially for the diagnosis of mid-ureteric stones larger than 5 mm, the Kendall's W for the combined gray-scale and color Doppler flow imaging ultrasound scanning modes was greater than that for the gray-scale mode (P < 0.05). Additionally, significant improvements in the diagnostic sensitivity, negative predictive value, and accuracy were noted with color Doppler imaging (P < 0.05). Under isolated gray-scale mode, the resident group had reduced diagnostic sensitivity and negative predictive value and poorer accuracy compared with the attending and senior groups (P < 0.05). In contrast, no significant differences in the combined gray-scale and color Doppler flow imaging modes were noted among all groups (P > 0.05). In summary, the color Doppler flow imaging mode is useful for the diagnosis of mid-ureteric stones larger than 5 mm, especially in the resident group.

Predictive Factors of Ureterorenoscopy Outcomes in Proximal Ureteral Stones: A Multicenter Study of Aegean Study Group of the Society of Urological Surgery

INTRODUCTION

We aimed to evaluate the predictive factors in a holistic manner for ureterorenoscopy (URS) outcomes in proximal ureteral stones by a multicenter study.

MATERIALS AND METHODS

The data of patients who underwent URS for proximal ureteral stones between the years 2015 and 2018 in eight centers were recorded retrospectively. Patients were divided into two groups according to URS success: Group 1 consisted of patients with successful URS, and Group 2 consisted of patients with unsuccessful URS. The two groups were compared in terms of risk factors, stone, and clinical characteristics of patients.

RESULTS

A total of 638 patients were included in the study. Group 1 consisted of 527 (82.6%) patients, and Group 2 consisted of 111 (17.4%) patients. In multivariate logistic analysis, the key risk factors for URS success was found to be age (OR = 0.980, 95% [CI] = 0.963-0.996, p = 0.018), stone area (OR = 0.993, 95% [CI] = 0.989-0.997, p = 0.002), and operation time (OR = 0.981, 95% [CI] = 0.968-0.994, p = 0.005).

CONCLUSIONS

To make the treatment decision of proximal ureteral stones, it is necessary to examine several parameters including available equipment, stone, and patient characteristics. Physicians should keep these risk factors in mind in the decision of treatment options.

Aktualisierung der S2k-Leitlinie zur Diagnostik, Therapie und Metaphylaxe der Urolithiasis (AWMF Registernummer 043-025)

Die Zunahme des medizinischen Wissens, technische Neuerungen gemeinsam mit demographischem Wandel stellen eine Herausforderung an die Neukonzeption von Leitlinien und klinischen Studien dar. Die vorliegende S2k-Leitlinie, die sich ausschließlich mit Nieren- und Harnleitersteinen beschäftigt, soll die Behandlung von Harnsteinpatienten in Klinik und Praxis unterstützen, aber auch Patienteninformationen zur Urolithiasis geben. Die zunehmende interdisziplinäre Zusammenarbeit in der Steintherapie zeigt sich auch an der Anzahl beteiligter Fachgruppen und Arbeitsgemeinschaften in der Erstellung des neuen Leitlinienupdates. Die vorliegende, aus einem interdisziplinären Konsensusprozess hervorgegangene S2k-Leitlinie stellt die aktuellen Empfehlungen praxisnah dar und gibt Entscheidungshilfen für Diagnostik‑, Therapie- und Metaphylaxemaßnahmen auf Basis von Expertenmeinungen und verfügbaren Evidenzgrundlagen aus der Literatur.

Imaging in Suspected Renal Colic: Systematic Review of the Literature and Multispecialty Consensus

BACKGROUND

Renal colic is common, and CT is frequently utilized when the diagnosis of kidney stones is suspected. CT is accurate but exposes patients to ionizing radiation and has not been shown to alter either interventional approaches or hospital admission rates. This multi-organizational transdisciplinary collaboration sought evidence-based, multispecialty consensus on optimal imaging across different clinical scenarios in patients with suspected renal colic in the acute setting.

METHODS

In conjunction with the American College of Emergency Physicians (ACEP) eQual network, we formed a nine-member panel with three physician representatives each from ACEP, the ACR, and the American Urology Association. A systematic literature review was used as the basis for a three-step modified Delphi process to seek consensus on optimal imaging in 29 specific clinical scenarios.

RESULTS

From an initial search yielding 6,337 records, there were 232 relevant articles of acceptable evidence quality to guide the literature summary. At the completion of the Delphi process consensus, agreement was rated as perfect in 15 (52%), excellent in 8 (28%), good in 3 (10%), and moderate in 3 (10%) of the 29 scenarios. There were no scenarios where at least moderate consensus was not reached. CT was recommended in 7 scenarios (24%), with ultrasound in 9 (31%) and no further imaging needed in 12 (45%).

SUMMARY

Evidence and multispecialty consensus support ultrasound or no further imaging in specific clinical scenarios, with reduced-radiation dose CT to be employed when CT is needed in patients with suspected renal colic.

Sonographic twinkling artifact for diagnosis of acute ureteral calculus

OBJECTIVE

We compared the performance of color Doppler twinkling artifacts with B-ultrasound and computed tomography (CT) for diagnosis of ureteral calculus in patients with acute renal colic.

METHODS

The location and size of ureteral stones in 2268 patients with acute renal colic were determined using the two ultrasound methods and CT. All cases were followed up for 2-8 weeks.

RESULTS

Color Doppler twinkling artifacts had a sensitivity of 96.98%, specificity of 90.39%, positive predictive value (PPV) of 99.77%, and negative predictive value (NPV) of 41.23%. B-Ultrasound had a sensitivity of 96.39%, specificity of 80.77%, PPV of 99.53%, and NPV of 34.43%. CT had a sensitivity of 99.59%, specificity of 94.23%, PPV of 99.86%, and NPV of 84.48%. The area under the receiver operating characteristic curve was 0.925 for color Doppler twinkling artifacts, 0.863 for B-ultrasound, and 0.963 for CT.

CONCLUSION

For the diagnosis of ureteral calculus, the sonographic twinkling artifact had a similar performance as CT. We suggest use of the sonographic twinkling artifact instead of CT for patients with acute renal colic to reduce the examination time and exposure to radiation, and to provide earlier access to treatment.

An investigation into the clinical accuracy of twinkling artifacts in patients with urolithiasis smaller than 5 mm in comparison with computed tomography scanning

Background

Ultrasound (US) is a non-invasive method used for the diagnosis of urolithiasis. If the size of the stone is <5 mm, it may be difficult to diagnose. This study aimed to compare the accuracy of twinkling artifact (TA) of color Doppler US imaging with unenhanced computed tomography (CT) for detecting urolithiasis <5 mm.

Materials and Methods

This prospective study was conducted on 100 patients with suspected renal calculus presented to the emergency room at the Imam Khomeini Hospital of Ahwaz in 2018. The US findings such as posterior acoustic shadowing and TA were examined for their ability to detect urinary stones (greatest diameter ≤5 mm) using CT findings as the gold standard.

Results

The mean size of renal stone was 3.43 ± 0.80 mm in CT and 3.49 ± 0.82 mm in color Doppler US. There was no significant difference between CT and color Doppler US report in quantification of urolithiasis sizes (P = 0.603). TA on color Doppler US was detected in 94 (94%) patients while posterior acoustic shadow was detected in 83 (83%) patients (P = 0.004). A significant difference was found between the TA and size of stones (P = 0.036). The sensitivity, accuracy, and positive predictive values of TA for the detection of calculus were 94%, 94%, and 100%, respectively.

Conclusion

The results demonstrated that TA on color Doppler US could be a good and safe alternative imaging modality with comparable results with non-contrast-enhanced computed tomography for the sensitive detection of urolithiasis <5 mm.