Ultrasonographic diagnosis of renal stones

Sonographic Evaluation of Renal Appearance in 665 Adult Volunteers

The purpose of this study was to investigate the sonographic appearance of the normal adult kidney. Parenchymal echogenicity, pyramid visibility, and transverse pelvis diameter of the kidneys were prospectively determined in an age- and sex-stratified random sample of 665 volunteers 30, 40, 50, 60, and 70 years old. Furthermore, incidences of kidney stones and split sinus echo were determined. The relation between obesity and above-mentioned parameters was evaluated. In the 30-year-old age group the right kidney was isoechoic as compared to the liver in 1/3, and had clearly or faintly visible pyramids in 2/3 of the cases. These rates decreased gradually with increasing age. Transverse diameter of renal pelvis ≥10 mm was observed in 13% of participants. Renal stones were observed in 2.1%. The incidence of split sinus echo was 3.6%. Obese participants showed lower incidences of isoechogenicity, pyramid visibility, pelvic ectasia, and split sinus echo. Isoechoic parenchyma, clearly visible pyramids, and transverse pelvis diameter ≥10 mm are not uncommon sonographic findings in normal adult kidneys and should not be used as indicators of renal pathology.

The comparison of ultrasound and non-contrast helical computerized tomography for children nephrolithiasis detection

AIMS

Nephrolithiasis is less common in children than adults, but its diagnosis and management in children may be more perplexing. In this article, we compare two imaging ultrasound (US) and non-contrast helical computerized tomography (CT) for diagnosis of nephrolithiasis.

SUBJECTS AND METHODS

A total of 20 children who diagnosed as nephrolithiasis by US were imaged simultaneously by non-contrast helical CT. Their history like as family history in first and second degree relatives and urine analysis for hematuria and urine randomly calcium to creatinine ratio was obtained. All data analyzed by χ(2) and Mann-Whitney U-test in SPSS 16 and P < 0.05 was considered to be significant.

RESULTS

Out of 20 cases, only 5 cases diagnosed as nephrlithiasis by US were confirmed by CT method 2 out of 20 cases had another extrarenal origin for their complaint who diagnosed wrongly as nephrolithiasis by US. Stone size based of US that was confirmed by CT method was larger 4.6 ± 1.5 (minimum 3 max 6 mm) than non-confirmed ones 2.3 ± 0.7 mm (P 0.002). Hematuria occurred more in correct diagnosed compared with misdiagnosed (P 0.005). Positive family history and urine calcium ratio was not differed between two groups.

CONCLUSIONS

Non contrast helical CT is essential to confirm of nephrolithiasis and other extrarenal origin of complaints, which diagnosed wrongly as nephrolithiasis in children. Stone size and presence of hematuria are two major factors for right diagnosis of nephrolithiasis as US method but Urine calcium excretion ratio or positive family history cannot be predictive as this study.

Sonographic mimics of renal calculi

OBJECTIVES

To review sonographic findings that can mimic renal calculi.

METHODS

We comment on a number of echoes that can mimic renal calculi.

RESULTS

There are a number of sonographic renal artifacts, vascular and nonvascular, that may confound a correct diagnosis.

CONCLUSIONS

Awareness of these potential artifacts will result in a more specific sonographic examination and will accurately guide the referring physician toward appropriate patient treatment. The importance of other imaging modalities is also emphasized to ensure that a correct diagnosis is obtained whenever the sonographic findings are inconclusive.

Urinary tract stones--Part I: role of radiological imaging in diagnosis and treatment planning

The modern management of urolithiasis requires a multi-disciplinary approach. Imaging plays a central role in both diagnosis and planning therapy of renal and ureteric calculi. This article reviews the current status of diagnosis and management of stone disease, and the contribution of radiological imaging in accurately triaging a given case to the most appropriate therapy.

Can dipstick screening for hematuria identify individuals with structural renal abnormalities? A sonographic evaluation

The present study presents data from a population study of 659 randomly selected adult volunteers. All participants had a renal sonographic examination and at the same time had their urine tested for hematuria by dipstick. Thirty participants (5%) had dipstick hematuria. Similar rats of abnormal renal findings were obtained in the hematuria-positive and hematuria-negative groups, 10% and 8%, respectively. Our results suggest that dipstick investigation for hematuria in mass-screening programs is not effective for the detection of structural renal abnormalities.

Ultrasonic diagnosis of ureteral calculi in patients with acute flank pain

The diagnostic value of ultrasonography (US) and intravenous urography has been compared in a prospective study comprising 123 consecutive patients with severe acute flank pain of less than 72 hours' duration. Ultrasonography was performed transabdominally with a 5 MHz sector real-time transducer. Ureteral calculi were considered the final diagnoses in 46 patients, of which 35 with and 11 without accompanying hydronephrosis. Ureteral calculi were correctly diagnosed by US in 17 patients (sensitivity 37%). If hydronephrosis with or without calculus is included as a positive sign of ureteral calculus, a correct diagnosis was suggested by US in 34 patients (sensitivity 74%). We consider US to be a valuable method in patients with previous contrast media reactions, but recommend urography as the standard imaging method when renal colic is clinically suspected.

Ultrasonography versus intravenous urography in the evaluation of patients with microscopic haematuria

Urography and transabdominal ultrasonography of the urinary tract were compared in 193 patients with microhaematuria. Of 16 expansile lesions described at urography, 1 renal carcinoma was detected by both methods. Although the number of patients studied is too small for firm conclusions to be drawn, ultrasonography seems to offer advantages when compared with urography.

Intravenous urography versus ultrasonography in evaluation of women with recurrent urinary tract infection

Intravenous urography and ultrasonography were compared prospectively in 120 women with recurrent urinary tract infection. The median age was 44 years (range 15-85). There was good correlation between the two methods in detecting hydronephrosis, calculi greater than or equal to 5 mm, and major post-pyelonephritic scarring. Urography was superior in detecting small cortical scars, slight caliceal dilatation, and less than or equal to 4 mm calculi. Based on the good results, low cost, and absence of radiation hazards or contrast media reactions, we conclude that ultrasonography may replace urography when a radiological screening of the upper urinary tract is deemed necessary in women with recurrent urinary tract infection.

The evaluation of suspected renal colic: ultrasound scan versus excretory urography

Patients commonly present to the emergency department with a suspected diagnosis of renal colic. A prospective study of 98 patients presenting with acute flank or abdominal pain or both was conducted to determine the diagnostic accuracy of ultrasound scan compared with excretory urography for the diagnosis of urinary tract calculi. All patients underwent standardized ultrasound scan and excretory urography as independent procedures. Two staff radiologists who reported the procedures were blinded to the results of the other diagnostic test and ultimate clinical outcome. All patients discharged home from the ED were followed to the hospital urology clinic. The diagnosis of urinary calculus was made only by identification of calculus at surgery or by reported passage of a stone by the patient. Of 85 patients available for follow-up study (56 men, 29 women; mean age, 40.5 years; range 18 to 77 years), calculi were identified in 69 (81%). Ultrasound identified calculi in 44 patients (sensitivity, 64%; specificity, 100%). Excretory urography identified calculi in 44 patients (identical sensitivity and specificity). When the presence of obstructive hydronephrosis only was used to diagnose renal calculi, ultrasound scan identified 59 patients (sensitivity, 85%; specificity, 100%) and excretory urography identified 62 patients (sensitivity, 90%; specificity, 94%). When the results of both diagnostic modalities were combined, calculi were identified in 59 patients (sensitivity, 85%; specificity, 100%) and hydronephrosis was seen in 66 patients (sensitivity, 95%; specificity, 94%). Our study shows that the diagnostic abilities of these procedures are equal in the detection of renal calculi.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal ultrasound versus intravenous urography in the evaluation of infravesically obstructed males

In a prospective study intravenous urography (IVP) and abdominal ultrasonography (US) were compared in 100 consecutively admitted male patients with symptoms of infravesical obstruction. No pathology was found in 67 patients on IVP and in 61 patients on US. Both modalities disclosed 5 bilateral, 4 unilateral hydronephroses and one patient with contracted kidneys. IVP found 7 renal masses: one solid tumour, 2 "possibly solid" tumours and 4 "possibly cysts", whereas US found one solid tumour and 16 cysts. Both modalities detected 3 kidney stones, 5 bladder stones and 3 bladder tumours. It is concluded that "imaging" of the urinary tract is only indicated in cases of haematuria, elevated creatinine, history of renal calculous disease and other clinical suspicion of upper urinary tract disease. It is further concluded that US is preferable to IVP in this patient category due to (1) better characterization of renal masses, (2) the possibility of investigating the liver and the retroperitoneum in the same setting, (3) better evaluation of the prostate with respect to size, (4) better evaluation of the bladder, and (5) last but not least for economical reasons. However, bone metastases will be missed.