VIENNA - Ultrasound is considered to be a rather challenging modality for detecting ureteral stones, but it worked like a charm for Drs. Jongmin Kim and S. H. Kim from the Jinju Gospel Hospital in Jinju, South Korea. Ultrasound left no stone unfound in the team’s eight-month study of emergency-room patients, as confirmed in follow-up imaging studies and clinical interventions.
"We prospectively evaluated ultrasound, IVP, and sometimes CT in 153 consecutive patients presenting with renal colic for the emergency evaluation of ureteral stones," Dr. Jongmin Kim said yesterday in a presentation at the European Congress of Radiology. "US was performed in a state of moderate bladder distension after ingestion of (500 ml) fluid prior to the study."
The diagnostic criterion for ureteral stones was an echogenic focus having posterior acoustic shadowing within the ureteral lumen, and the final diagnosis was confirmed by additional imaging, clinical follow-up, or urological intervention in all cases, Kim said. For the purposes of the study, ureteral stone locations were divided into upper, middle, and lower thirds of the ureter.
According to the results, ureteral stones (mean size 8.0 mm, range 3.5 to 23.8 mm) were detected in 140/153 cases. The remaining 13 patients were diagnosed with appendicitis (n=3), choleodocholithiasis (n=1), choleocystitis (n=1), acute pyelonephritis (n=1), hemorrhagic ovarian cyst (n=1), diverticulitis (n=1), and five unknown cases.
"Ninety-five cases or 68% (of the ureteral stones) were located at the lower third of the ureter, including 69 cases at the ureteropelvic junction," Kim said. "And 29% and 3% were in the upper and middle thirds, respectively."
Ninety-nine cases or 71% revealed calcified stones on follow-up radiography, but the remaining 41 cases did not. In one case, CT failed to visualize a stone seen with ultrasound. Hydronephrosis was noted in 108/140 (77%) of the patients.
"It was difficult for ultrasound to trace throughout the ureter, in many cases due to bowel gas," he said. "Nonetheless, there were some cases where moderate bladder distension could help visualize (stones). Posture change could also help to avoid bowel gas (artifacts) posterior to ureteral stones in many cases."
Anatomic landmarks such as the psoas muscle and ureteropelvic junction, as well as the use of color Doppler ultrasound, were also helpful in differentiating the ureter from vessels, and ureteral stones from bowel gas, he said. All diagnoses were confirmed with IVP, CT, or clinical intervention.
"Ultrasound was very useful for the diagnosis of ureteral stones, with a sensitivity of 100%," Kim concluded. An audience member said the patients seemed quite small and slender on follow-up CT, and asked if their diminutive size might have aided the performance of ultrasound.
"I am Korean," Kim said. "The average weight is not so heavy. But we didn’t exclude anyone from the prospective study."
By Eric BarnesAuntMinnie.com staff writer
March 7, 2004
Related Reading
US calculates splenic volume within ten minutes, January 19, 2004
US combo boosts detection, characterization of perianal inflammation, January 15, 2004
3-D ultrasound shows promise in neonatal, pediatric neurosonography, November 4, 2003
3-D ultrasound offers reliable assessment of gallbladder, bile ducts, May 5, 2003
Power Doppler US spots tumor vascularity for prostate cancer staging, April 30, 2003
Copyright © 2004 AuntMinnie.com
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&fit=crop&h=100&q=70&w=100)
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
