Can Freehand Elastosonography Be an Alternative to Renal Scintigraphy in Pediatric Vesicoureteral Reflux Cases?

INTRODUCTION: Detecting renal scar is important in pediatric patients with vesicoureteral reflux (VUR) for deciding on treatment option. The aim of this study is to detect whether freehand elastosonography technique could be an alternative to dimercaptosuccinic acid (DMSA) scan in determining renal scar formation. MATERIALS AND METHODS: Between November 2015 and April 2016, 25 VUR patients, age ranging from 3 to 17 years admitted to our clinic, had urinary ultrasound and elastosonography, and data of approximately 147 renal region were recorded. Data were upper, middle, and lower pole renal parenchymal thickness and echogenicities obtained by ultrasound and these poles strain target (ST), strain reference (SR), and strain index (SI) values obtained by freehand elastosonography. DMSA scan data (differential function and upper, middle, and lower pole parenchymal scar formation) were recorded. RESULTS: Scar formation and more than 10% reduction in differential function in renal scan were statistically higher in renal regions in which parenchymal thinning and echogenicity increase was detected by ultrasound. There was no elastosonographic data difference between renal units with and without differential function decrease. Also, there was no elastosonographic data difference between renal units with and without scar formation. CONCLUSION: In this study, we could not find any significant difference in term of tissue tension values (ST and SI) measured by freehand elastosonography between renal units with and without scar formation in renal scan.

Ureterocolic fistula diagnosed on the basis of diuretic renogram and direct radionuclide cystography.

Ureterocolic fistulae are a rare phenomenon and are most commonly seen secondary to obstructive ureteric calculi. These are usually diagnosed on barium enema or intravenous urography. Most of the times, more than one investigation is needed to confirm the findings. We present a case of iatrogenically-induced ureterocolic fistula, diagnosed on renogram and direct radionuclide cystography. This case showcases the possibility of using a renogram study as a diagnostic tool for a suspected ureterocolic fistula. A renogram study also enables to asess the renal function, which is essential in deciding the management.

Losartan renography for the detection of renal artery stenosis: comparison with captopril renography and evaluation of dose and timing.

PURPOSE: Radionuclide renography with angiotensin converting enzyme (ACE) inhibition plays an important role in the diagnosis of haemodynamically significant renal artery stenosis. Angiotensin receptor antagonists inhibit the renin angiotensin system at different levels from ACE inhibitors by selectively blocking the binding of angiotensin II to AT1 receptors. The AT1 angiotensin receptor antagonist losartan has recently been used clinically in the treatment of hypertension. However, the available data on the use of losartan with renography for the detection of renovascular hypertension are limited and contradictory. The purpose of this prospective study was to compare the effectiveness of losartan renography and captopril scintigraphy in revealing renal artery stenosis. METHODS: A total of 61 renal units in 32 patients with hypertension were studied in two groups based on the losartan dosage (50 mg in group A and 100 mg in group B). Group A consisted of 17 patients, in whom 19 renal units had angiographically proven renal artery stenosis (>or=50%). In group B, there were 15 patients, in whom 20 renal arteries were stenotic. All of the patients underwent three renographies (baseline, captopril renography and early losartan renography). Early losartan renography was performed at 1 h after oral losartan administration in both groups. In group B, seven patients underwent additional losartan renography (late losartan) performed 3 h after oral losartan administration; these patients composed group B1. RESULTS: The sensitivities of captopril and losartan studies were 63.2% and 42% in group A, 65% and 65% in group B and 55.6% and 66.6% in group B1, respectively. CONCLUSION: From our preliminary results, we conclude that losartan is not superior to captopril renography for the detection of haemodynamically significant renal artery stenosis. However, a high dose (100 mg) of losartan provided higher sensitivity than the lower dose (50 mg). Late losartan scintigraphy provided similar diagnostic efficacy to early losartan renography.

Prospective study of simultaneous orthoiodohippurate and diethylenetriaminepentaacetic acid captopril renography. The Einstein/Cornell Collaborative Hypertension Group.

UNLABELLED: Captopril renography (CR) has been established in the past 10 yr as a useful diagnostic test for renovascular hypertension. However, direct comparison of tubular and glomerular tracers, quantitative criteria, comparison of quantitative and qualitative results and the reliability of the results in renal failure have not been described in a systematic, prospective fashion. METHODS: Same-day baseline and CR using 99mTc-labeled diethylenetriaminepentaacetic acid (DTPA) and [131I]orthoiodohippurate (OIH) were simultaneously performed in two groups of hypertensive subjects, one with demographically defined essential hypertension (n = 43) and the other (n = 60) with a high prevalence of renovascular disease, defined with angiograms. Quantitative criteria for abnormal CR were derived from results among the subjects with essential hypertension. Qualitative analysis was performed using widely established criteria. RESULTS: There were no statistically significant differences between quantitative and qualitative accuracy, between OIH and DTPA or among quantitative parameters. The best accuracies for quantitative CR were 56% with DTPA (n = 57) and 60% with OIH (n = 60), in both cases using the relative renal uptake parameter. Qualitative CR (n = 60) had accuracies of 43% (DTPA) and 50% (OIH), both hindered by 29 (DTPA) and 25 (OIH) abnormal but nondiagnostic studies. Two false-positive studies were detected. Twenty-seven of 29 nondiagnostic studies were associated with a glomerular filtration rate of <50 ml/min (n = 17), one small kidney (n = 17) and/or bilateral renal artery stenosis (n = 16). Supplemental measurement of in vitro stimulated plasma renin activity insignificantly (p > 0.10) and improved accuracies to 63% (DTPA) and 70% (OIH), without introducing additional false-positive tests. CONCLUSION: Orthoiodohippurate and DTPA have comparable accuracy in prospective simultaneous evaluation of CR. False-positive studies are fewer than 5%. The accuracies of quantitative and qualitative criteria do not differ significantly but may be improved by supplemental use of the in vitro stimulated plasma renin activity. In individuals with renal insufficiency, small kidneys and/or bilateral renal artery disease, up to 48% of CR studies are abnormal but nondiagnostic.

[Significance of a nonionic renographic contrast medium (Iopamidol 300) in the roentgen diagnosis of the kidneys and urinary tract in children]. / Die Bedeutung eines nichtionischen nierengängigen Kontrastmittels (Iopamidol 300) in der Röntgendiagnostik der Nieren und Harnwege bei Kindern.

The ionic contrast media used so far have been associated with considerable risks in infants and children. The high osmolality of these media did not always permit a dosage sufficient for kidney imaging in the nephrographic and in the pyelographic phase. The new non-ionic contrast media have largely reduced these risks so that their general application in infants and young children should be recommended. Intravenous urographies using the non-ionic contrast medium Iopamidol 300 (Solutrast 300) were performed in 195 children aged one day to 12 years. Good to superior urograms were obtained in 85% of the investigations. No adverse reactions caused by the osmolality of the contrast media had been observed in spite of the relative high dosage. As a result of their low osmolality and non-ionic property a safe application of high doses was possible.

Kidney scintigraphy with 99mTc-DMSA and 131I-hippurate.

43 patients underwent an extended scintigraphic procedure with 99mTc-dimercaptosuccinylic acid in order to investigate its proper use for diagnosing morphological and functional kidney abnormalities. The group was comprised of patients without renal disease, and patients with diffuse parenchymal disease, obstructive uropathy, renal cysts and renal tumors. The study was followed by 131I-hippurate renography. We propose a simplified routine procedure with scintiphotos taken 10-15 min after injection for topographic information and 120 min after injection for renal morphology. This procedure allows excellent case finding of diffuse parenchymal disease of a special value in cases of radiological non-visualization. The technique is indicated, when iodine contrast media cannot be used for radiological examinations. DMSA studies, however, do not allow safe functional evaluation in all categories of patients. Neither can obstructive nephropathy be diagnosed unless the renal pelvis is dilated. Renal perfusion studies are contaminated by the perfusion of liver and spleen. Nevertheless, a tentative differentiation between cysts and tumours is possible, the former being hypoperfused the latter hyperperfused. When supplemented with gamma camera 131I-hippurate renography, the total scintigraphic procedure will also include split function determination and run-off evaluation.