Indirect Radionuclide Cystography Research Articles

Nuclear medicine and pediatric nephro-urology: a long-lasting successful partnership.

Congenital anomalies of the kidney and urinary tract, as well as urinary infections, are very frequent in children. After the clinical and laboratory evaluation, the first imaging procedure to be done is a renal and bladder ultrasound, but afterwards, a main contribution comes from nuclear medicine. Through minimally invasive and sedation-free procedures, nuclear medicine allows the evaluation of the functional anatomy of the urinary tract, and the quantification of renal function and drainage. If pediatric dosage cards provided by scientific societies are used, radiation exposure can also be low. In the pediatric conditions previously mentioned, nuclear medicine is used both for initial diagnosis and follow-up, mostly in cases of suspicion of ureteropelvic or ureterovesical junction syndromes, as well as vesicoureteral reflux or renal scars of febrile infectious episodes. Pediatric nephro-urology constitutes a significant workload of pediatric nuclear medicine departments. The following paragraphs are a revision of the renal radiopharmaceuticals, as well as the nuclear nephro-urology procedures - dynamic and static renal scintigraphy, and direct and indirect radionuclide cystography. A summary of the techniques, main indications, interpretation criteria and pitfalls will be provided. Some future directions for the field are also pointed out, among which the most relevant is the need for nuclear medicine professionals to use standardized protocols and integrate multidisciplinary teams with other pediatric and adult health professionals that manage these life-long pediatric pathologies, which are recognized as an important cause of adult chronic kidney disease.

Diagnosing and treating occult vesicoureteric reflux using PIC cystography: Is it influenced by abnormalities on DMSA?

Positioning the Instillation of Contrast cystography (PICc) is used to identify occult vesicoureteric reflux (VUR) in patients with recurrent urinary tract infections (UTI) despite optimized bladder and bowel function and without VUR demonstrated on conventional imaging. To determine the incidence of finding occult VUR in such patients usingPICc and the benefit, if any, of treating it. We also assessed if this was influenced by abnormalities on the pre-operative DMSA. This was a retrospective review of PICc in our hospital between 2016 and 2018 and involved three paediatric urologists. The primary indication for PICc was two or more culture proven UTIs despite optimized bladder and bowel function and no reflux on voiding cystourethrography (VCUG) or indirect radionuclide cystography (I-RNC). All children had a preoperative DMSA scan to document any abnormalities. PICc was performed in a standardized way to each ureteric orifice. If occult reflux was found, it was treated concomitantly by cystoscopic injection of Deflux®. To assess the influence of the pre-operative DMSA status, the cohort was subdivided into two groups based on the DMSA scan: Group 1-abnormal DMSA, Group 2-normal DMSA. The median follow-up was 26 months (range 3-39 months). PICc was performed in 25 patients [23 females and 2 males; median age: 7 years (range 2-16 years; IQR=4)]; 17 from Group 1 and 8 from Group 2. Occult VUR was identified in 22 patients (88%); 15/17 (88.2%) in Group 1 and 7/8 (87.5%) in Group 2 (p=0.9). After cystoscopic treatment, 21/25 (84%) became infection free and this was not influenced by the preoperative DMSA status (p=0.6). Fig 1. In this challenging group of patients, looking for and treating occult reflux appears to be clinically useful and beneficial. The ability to test and treat at the same sitting is an added advantage of PICc. The DMSA results did not influence the diagnostic or therapeutic aspect of the process. Our results concur with other published literature. There is a high incidence of finding occult reflux using PICc in this cohort of patients. Concomitant cystoscopic treatment led to 84% of children becoming infection free on follow up. Abnormalities on DMSA did not influence either the likelihood of finding occult reflux or the likelihood of successful treatment.

Comparison of Two Diagnostic Methods of Vesicoureteral Reflux in Children with Urinary Tract Infection

Introduction: Urinary tract infection is common in children and vesicoureteral reflux is one of its predisposing factors. Contrast cystography and radionuclide cystography are two common methods for the diagnosis of vesicoureteral reflux. This study compared two methods, indirect radionuclide cystography (IRC) with voiding cycling method and voiding cystoureterography with contrast (VCUG). Materials & Methods: This analytical study was conducted on 55 children with urinary tract infection who were referred to our nephrology clinic in six months. In order to diagnose urinary reflux, 109 ureters (one child had a single kidney) were evaluated using IRC and VCUG methods with a one-month interval. Kappa coefficient was used to determine the agreement rate, and the McNemar’s test was employed to compare the ability of two methods in the diagnosis of VUR. Results: The mean age of the children was 5.4 years (range: 6 months to 13 years). A total of 38 children (69%) were female and 17 (30.9%) were male. Seventy percent of the children older than three years old had urinary control. From 109 ureters, 29 (26.4%) with urinary reflux were detected by the IRC method, whereas only 15 (13.6%) were diagnosed using VCUG. Statistically, the two methods did not have agreement in the diagnosis of VUR (Kappa: 0.556, p< 0.001) and the IRC method had more power to diagnose VUR in comparison with VCUG. Conclusions: Although we observed a significant difference in the diagnostic value of two methods, the choice of diagnostic method depends on specific technical conditions. However, in ideal conditions, the IRC method is suggested to be performed since it is more powerful in the diagnosis of urinary reflux. Keywords : Vesico-Ureteral reflux; Urinary Tract Infections; Pediatrics; Diagnostic Imaging.

2023 THE EFFECTIVENESS OF DIFFERENT DIAGNOSTIC METHODS IN DETECTION OF VESICOURETERAL REFLUX IN CHILDREN

INTRODUCTION AND OBJECTIVES: Evaluate the diagnostic value of direct radionuclide cystography, indirect radionuclide cystography dynamic nephroscintigraphy with voiding sample in comparing with “gold standard” micturation cystourethrography (MCUG) in the detecting of the vesicoureteral reflux (VUR). We assess three methods and made the indications for each of them. METHODS: Two groups of patients with VUR grade 2-4 were conducted. The first group included 72 patients (42 boys, 30 girls) in the age from 4 months to 18 years who were evaluated comparatively according to the results of indirect radionuclide cystography and MCUG; the second 20 patients in the age from 5 months to 8 years (5 girls, 15 boys) were evaluated with direct radionuclide cystography in comparing of MCUG. RESULTS: In the first group VUR was detected in 23 cases according to MCUG, in 33 according to indirect radionuclide cystography, in 16 by both methods. It should be noted that the discrepancy between the results was found in 59.7% of children aged from 6 months to 3 years with the VUR grade 2-3. In the second group 16 patients demonstrated matching results for both methods; 4 patients showed a discrepancy between the results: in 3 patients two-sided VUR was detected by direct radionuclide cystography but only one-side VUR by MCUG. CONCLUSIONS: Indirect radionuclide cystography is the method of choice in children elder than 3 years old. Direct radionuclide cystography in contrast to an indirect one provides a reliable and objective assessment of the presence of VUR in both filling and emptying phases of the bladder, as well as allowing to determine the functional capacity which causes VUR, its intensity and duration.

Dismembered extravesical reimplantation of dilated upper pole ectopic ureters in duplex systems

PurposeWe report the results in patients with obstructed upper pole ectopic ureters in duplex systems undergoing dismembered extravesical reimplantation of the upper pole ureter alone. MethodsBetween 01/2007 and 03/2012, 11 patients with an upper pole ectopic ureter (1 bilateral) diagnosed following the antenatal detection of hydronephrosis and showing preserved function on renal scintigraphy in a dilated upper moiety, underwent a dismembered reimplantation of the ectopic upper pole ureter as follows. The ureter was identified, separated from the lower pole ureter, and divided just above the bladder. The distal stump was suture closed, while the proximal segment was mobilized, tapered as necessary, and reimplanted using an extravesical technique. ResultsTwelve ectopic ureters were reimplanted. Median (range) patient age at surgery was 8 (3–48)months. Ureteral tapering was performed in 11 ureters, by infolding in 9 and using an excisional tailoring in the single case undergoing bilateral reimplantation. After a median (range) follow-up of 17 (6–50)months, all patients were asymptomatic. Eleven reimplanted ureters showed improving hydroureteronephrosis, no obstruction on diuretic scintigraphy, and no evidence of reflux on indirect radionuclide cystography. One reimplanted ureter developed worsening hydroureteronephrosis after excisional tailoring of the ureter and partial nephrectomy was performed. ConclusionsExtravesical reimplantation of the upper pole ureter is an option in dilated upper pole ectopic ureters with good function. Separating the upper and lower pole ureters proximally to the bladder does not jeopardize the ureteral blood supply and allows leaving the lower pole ureter undisturbed. Excisional ureteral tailoring should be avoided.

Reflux Nephropathy in Kidney Transplants, Demonstrated by Dimercaptosuccinic Acid Scanning

This study determines why kidney transplants develop new focal defects. Thirty children at a U.K. pediatric nephrology department receiving kidney transplants had early and late dimercaptosuccinic acid (DMSA) scans to detect acquired focal defects, and their presence correlated with possible risk factors. Associations between clinical events and focal DMSA lesions appearing in grafts were measured. Of the 30 early DMSA scans (within 2 weeks of function), one child with a thrombosed polar artery had a focal defect. On rescanning later, 11 (37%) had acquired segmental defects; five were multiple, and their glomerular filtration rates were 20 ml/min/1.73 m lower (95% CI 7-34). Histology in one case showed pyelonephritic scarring. Reflux into the transplant ureter occurred in 19/27 (70%) of children tested (by radiological or indirect radionuclide cystography). Nine of 13 children (69%) who had a combination of reflux and a urine infection had acquired scars, whereas only 1/14 (7%) did without this combination (P = 0.001). Scarring was not associated with the age or sex of the donor or recipient, rejection episodes, renal biopsy, or drug-induced nephrotoxicity. Kidney transplants are at high risk of developing segmental pyelonephritic scars if infected urine refluxes into the graft, either early through a transanastomotic stent or later from vesicoureteric reflux. These scars may reduce the renal function and are readily seen on DMSA, but not ultrasound scans. Consideration should be given to more effective antireflux surgery for transplants, with subsequent testing for reflux, urinary antibiotic prophylaxis, and prompt treatment of urine infections.

A31 Indirect radionuclide cystography in children: Physiological parameters associated with renal reflux

A31 Indirect radionuclide cystography in children: Physiological parameters associated with renal reflux

The role of indirect radionuclide cystography during the acute phase of pyelonephritis in young women

To review our experience using dynamic 99mTc-diethylenetriamine penta-acetic acid renal scintigraphy combined with indirect radionuclide cystography (IRC) in the acute phase of pyelonephritis, as a possible alternative to the conventional imaging, as investigating acute pyelonephritis usually includes imaging the upper urinary tract during the acute phase, to exclude obstruction, and delayed voiding cysto-urethrography (VCUG) when underlying vesico-ureteric reflux (VUR) is suspected. Between 1997 and 1999, 47 young women (median age 22 years, range 18-37) were hospitalized for acute pyelonephritis. The combined study was used during the acute phase of the disease, usually within 24 h of hospitalization. The principle of IRC is based on the reappearance of radioactivity in the ureters or kidneys after previously detecting renal clearance of an intravenously injected radioisotope. The increase in radioactivity over the ureters or kidneys indicates VUR. The subsequent follow-up included VCUG, after recovery and at least 6 weeks after discharge. Overall, 47 patients had early IRC studies; obstruction of the urinary tract during the acute phase of the disease was excluded in all. In 13 (28%) of the patients early IRC studies showed VUR involving 21 upper tract units. The renal parenchymal scan was impaired in 17 (36%) patients, and six of these 17 also had detectable concomitant reflux on IRC. Overall, 24 IRC studies (51%) were considered positive, showing VUR, renal parenchymal pathology or both; 23 (49%) were normal. Follow-up VCUG was used in 32 patients (68%); only three (9%) detected VUR. All of the patients with VUR on follow-up VCUG had also had an abnormal early IRC study, showing either reflux (two) or findings suggestive of pathological renal parenchyma (one). In addition to the well-established role of renal scintigraphy in excluding obstruction of the collecting system, early IRC is characterized by high sensitivity and accurate negative predictive value for detecting VUR. It can therefore be used to screen adults presenting with acute pyelonephritis for the presence of VUR. Patients with an abnormal IRC require follow-up VCUG after complete recovery, while those with a negative study may be managed expectantly, with no further radiological evaluation. This proposed strategy may avoid up to half of the delayed VCUG studies, preclude the related inconvenience, and substantially reduce the costs.

Direct and indirect radionuclide voiding cystography

Direct and indirect radionuclide voiding cystography

Vesicoureteral Reflux to an Ectopically Located Right Kidney Visualized on Indirect Radionuclide Cystography

A 5-year-old boy with an abnormality of chromosome 14 was referred to our department for the evaluation of vesicoureteral reflux. Indirect radionuclide cystography including renal scintigraphy was performed. In the case presented here, the location of the ectopic right kidney was demonstrated with indirect radionuclide cystography in a child with high-grade vesicoureteral reflux.

Radionuclide studies in paediatric nephro-urology

The main tool of radionuclide techniques applied to paediatric uro-nephrology is the quantitation of function, which is an information not easily obtained by other diagnostic modalities. The radiation burden is low. Drug sedation is only rarely needed, whatever the age of the patient. Accurate determination of glomerular filtration rate can be obtained by means of an intravenous injection of Cr-51 EDTA and one or two blood samples. Tc-99m DMSA scintigraphy is an accurate method for evaluation of regional cortical impairment during acute pyelonephritis and later on, for detection of permanent scarring. Tc-99m MAG3 renography is nowadays a well-standardized method for accurate estimation of the split renal function and of renal drainage with or without furosemide challenge. This technique is particularly indicated in uni- or bilateral uropathies with or without renal and/or ureteral dilatation. Direct and indirect radionuclide cystography are two alternative modalities for X-ray MCUG. Their relative place in the strategy of management of vesicoureteral reflux is discussed.

Cystosonography With Echocontrast: A New Imaging Modality to Detect Vesicoureteric Reflux in Children

No AccessJournal of UrologyUrological Survey: Abstracts: Pediatric Urology1 Oct 1998Cystosonography With Echocontrast: A New Imaging Modality to Detect Vesicoureteric Reflux in Children M. Bosio M. BosioM. Bosio More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(01)62645-4AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Cystosonography With Echocontrast: A New Imaging Modality to Detect Vesicoureteric Reflux in Children." The Journal of Urology, 160(4), p. 1592 Paediatric Department, Magenta Hospital and Advanced School of Paediatric Ultrasonography, Magenta, Italy© 1998 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 160Issue 4October 1998Page: 1592 Advertisement Copyright & Permissions© 1998 by American Urological Association, Inc.MetricsAuthor Information M. Bosio More articles by this author Expand All Advertisement PDF DownloadLoading ...

A study of reflux in patients with an ileal orthotopic bladder.

To determine whether there is vesico-ureteric reflux during voiding in patients who had undergone an ileal bladder substitution after cystectomy. The study comprised 15 patients (13 men and two women) who had undergone radical cystectomy and construction of a Studer ileal neobladder. At 1-24 months (median 4) after the operation indirect radionuclide cystography (IRC) was performed after isotopic renography (using 99m-technetium mercapto-acetyltriglycine) and voiding cysto-urethrography (VCUG). None of the patients had reflux during voiding, either on IRC or on VCUG. Renal function and morphology remained stable in all patients. Despite bacteriuria occurring in four patients, no episode of pyelonephritis was reported. There was no vesico-ureteric reflux during voiding in patients with a Studer ileal bladder substitution. However, long-term follow-up is needed to finally determine whether an antirefluxive ureteric implantation is required to protect the upper urinary tract in patients with ileal low-pressure bladder substitutions.

How good is technetium-99m mercaptoacetyltriglycine indirect cystography?

The aim of the present study was to estimate the sensitivity of indirect radionuclide cystography (IRC) performed with technetium-99m mercaptoacetyl-triglycine (MAG3), in comparison with the micturition cystourethrography (MCUG) and direct radionuclide cystography (DRC), for the diagnosis of vesicoureteric reflux. Two groups of patients were selected: group I comprised 40 children who underwent IRC during the acute phase of urinary tract infection and an MCUG 6 weeks later; group II comprised 42 (other) children with known reflux, who underwent IRC and DRC during follow-up. Taking as the reference the total number of refluxing kidneys detected by means of any cystographic technique, 99mTc-MAG3 ICR missed two-thirds of the refluxing kidneys. Most of the small refluxes were missed, but so too were 50% of the major refluxes. Taking as the reference 99mTc dimercaptosuccinic acid (DMSA) scintigraphy, MCUG detected 91% of the patients with DMSA abnormalities on at least one kidney, DRC detected 95%, and IRC detected 46% and 43% respectively, in groups I and II. The use of 99mTc-MAG3 IRC as the sole technique for the detection of vesicoureteric reflux gives rise to an unacceptable number of false-negative results.

Scintigraphic evaluation of pediatric urinary tract infection

Scintigraphic evaluation of urinary tract infection, pyelonephritis, and renal scarring represents a significant portion of a clinical pediatric nuclear medicine practice. Renal scarring from recurring infection remains an important cause of end-stage renal disease and hypertension in the pediatric population. However, the clinical presentation in infants and young children is often elusive, and clinical diagnosis of upper tract involvement is frequently unreliable. As a result, diagnostic imaging has a critical role to play in the localization of infection to the lower or upper urinary tract. Radionuclide cystography and renal cortical imaging have become mainstays of this evaluation. Direct radionuclide cystography is the preferred cystographic screening technique, because it has lower radiation exposure and greater sensitivity for the detection of vesicoureteral reflux than either indirect radionuclide cystography or fluoroscopic contrast cystography. Renal cortical scintigraphy has become the standard for the detection of pyelonephritis and renal scarring. Correlation with histopathology has demonstrated a high degree of diagnostic accuracy. Acute pyelonephritis has been shown to be the necessary etiologic factor for the development of subsequent renal scarring, and the mechanism of renal injury in pyelonephritis has been extensively studied in experimental models. The ability of prompt and appropriate antibiotic therapy to dramatically reduce the incidence of subsequent scarring also has been conclusively demonstrated both clinically and in the experimental model. Vesicoureteral reflux was once thought to be a necessary prerequisite for the development of renal scarring. Although it is clear that the intrarenal reflux of infected urine will create pyelonephritis in the experimental model, the high incidence of pyelonephritis and subsequent scarring in the absence of demonstrable vesicoureteral reflux leaves the role of reflux in question. Although the role of vesicoureteral reflux is incompletely understood, its detection nevertheless remains a standard part of the patient's evaluation.

Indirect radionuclide cystography: A sensitive technique for the detection of vesicoureteric reflux

Indirect radionuclide cystography: A sensitive technique for the detection of vesicoureteric reflux

Indirect radionuclide cystography: a sensitive technique for the detection of vesico-ureteral reflux

The detection or exclusion of vesico-ureteral reflux (VUR) has classically been by micturating cystourethrography (MCUG). Radionuclide cystography will detect VUR but fails to provide the same detailed anatomical informations as MCUG. This study allowed a comparison of indirect radionuclide cystography (IRC) and MCUG in 65 children. Renal reflux was detected by IRC in 32% of renal units, while VUR was seen in 36% by MCUG. When a comparison was made with MCUG, IRC had a sensitivity of 74.1% and a specificity of 90.5%. The markedly reduced radiation dose, avoidance of a bladder catheter plus the ability to monitor the urinary tract constantly during the entire procedure should ensure that IRC is the examination of choice in follow-up studies for VUR in all toilet-trained children.

Indirect radionuclide cystography demonstrates reflux under physiological conditions

Indirect radionuclide cystography (IRC) is a useful technique for the detection and quantification of vesico-ureteric reflux (VUR). Its principal advantage over micturating contrast cysto-urethrography (MCU) is its ability to demonstrate VUR under physiological conditions. Three children (age range 6-9 years) reported here illustrate some physiological features of micturition readily seen only on IRC. The most important of these was uretero-ureteric reflux which, because of bladder activity, is not usually identifiable on IRC or MCU but is probably more common than previously thought and misinterpreted as VUR.

Direct and Indirect Radionuclide Cystography

Direct radionuclide cystography, using short half-life radiopharmaceuticals, is considered to be more reliable for detecting vesicoureteral reflux than conventional roentgenographic techniques. In addition to the detection of vesicoureteral reflux, other parameters determined include the bladder volume when reflux occurs, calculation of volume of fluid that has refluxed, accurate calculation of residual urine volume, estimation of reflux drainage time, and the visualization and diagnosis of gross anatomic abnormalities. Currently, a major disadvantage is poor resolution, prohibiting analysis of small bladder defects and urethral abnormalities.The major advantage of nuclear cystography is the small radiation dose delivered with its use. It is estimated that at least 100 radionuclide studies can be performed for the same radiation expense as a single roentgenographic study.

Direct and indirect radionuclide cystography

Direct radionuclide cystography has proved to be a useful substitute for roentgenological cystography in studying patients with vesicoureteral reflux. Although the initial diagnosis generally is made with x ray, serial follow-up examinations are more feasible with the radionuclide method because of its lower radiation burden. Additional information obtainable from these studies includes determinations of bladder volume at time of reflux, calculation of urine volume that has refluxed as well as residual bladder urine volume, quantification of reflux drainage time from the upper tracts, and visualization of anatomic defects and variants. More recently, indirect nuclear cystography has been evaluated for the detection of reflux. The greater degree of patient cooperation required for this procedure would appear to favor its usefulness in older children. More investigative work, including correlation with direct radionuclide cystography as well as the roentgenologic studies, is needed.