Kassa Darge

Imaging recommendations in paediatric uroradiology: minutes of the ESPR workgroup session on urinary tract infection, fetal hydronephrosis, urinary tract ultrasonography and voiding cystourethrography, Barcelona, Spain, June 2007

We present here a few basic proposals for algorithms and procedures for imaging the paediatric genitourinary tract based on initial discussion at a paediatric uroradiology symposium and proposals of the ESUR Paediatric Uroradiologic Guidelines Subcommittee. These recommendations were developed in the light of new knowledge that might influence existing guidelines. Regional, individual and local flexibility and variability should be preserved in order to make these recommendations applicable throughout Europe. They should help standardize dedicated imaging not only in terms of a quality measure to ensure state-of-the-art patient care, but also in forming a common basis for multi-institutional research. There is an urgent need for these guidelines in order to advance our understanding of the subject and to gain evidence and improve imaging efficacy. Our session worked towards establishing an agreement on imaging indications in common paediatric urological conditions, respecting the ALARA principle, and patient safety and care, and taking into account state of the art knowledge and efficacy aspects. We started the task with a reassessment of (1) imaging in urinary tract infection in infants and children, (2) postnatal imaging in mild-to-moderate neonatal hydronephrosis, (3) how to perform voiding cystourethrography, and (4) procedural recommendations for paediatric urosonography. This list is incomplete, and future recommendations will be developed, discussed and presented at forthcoming meetings.

Voiding urosonography with US contrast agents for the diagnosis of vesicoureteric reflux in children. II. Comparison with radiological examinations.

Studies comparing voiding urosonography (VUS) with voiding cystourethrography (VCUG) and direct radionuclide cystography (DRNC) were analyzed and detailed tables demonstrating the diagnostic values and grading of vesicoureteric reflux (VUR) are presented. Comparative studies of DRNC were too few and did not allow definite conclusions. Using VCUG as the reference, the results of VUS were as follows: sensitivity 57–100%, specificity 85–100%, positive/negative predictive values 58–100%/87–100%, respectively, and diagnostic accuracy 78–96%. With the exception of two studies the diagnostic accuracy reported was 90% and above. In 19% of pelviureteric units (PUUs) the diagnosis was made only by VUS and in 10% only by VCUG. Thus in 9% of PUUs more refluxes were detected using VUS. In 73.6% the reflux grades were concordant in VUS and VCUG. Reflux grade was found to be higher with VUS than with VCUG in 19.6% of PUUs. In 71.2% of PUUs with grade I reflux on VCUG, the reflux was found to be grade II and higher on VUS. The common selection criteria for VUS as the primary examination for VUR currently include (a) follow-up studies, (b) first examination for VUR in girls, and (c) screening high-risk patients.

Structured treatment interruption in patients with alveolar echinococcosis

In human alveolar echinococcosis (AE), benzimidazoles are given throughout life because they are only parasitostatic. It has been a longstanding goal to limit treatment, and recent reports suggest that, in selected cases, benzimidazoles may be parasitocidal. Previously, we showed that positron –emission tomography (PET) using [18F]fluoro‐deoxyglucose discriminates active from inactive lesions in AE. We have now performed a 3‐year prospective study in 23 patients and conducted a structured treatment interruption in those without signs of PET activity. Disease progression was further assessed by ultrasound, computerized tomography, laboratory parameters, and clinical examination.We found PET‐negative lesions in 15 of 23 patients and benzimidazoles were discontinued in these patients. After 18 months, patients were reevaluated, and, of the 15 initially PET‐negative patients, 8 showed either new activity on PET (n = 6) or signs of clinical progression (n = 2). Reinitiation of benzimidazoles halted parasite growth again. No further progression was detected after 36 months. PET had a sensitivity of 91% for the detection of active lesions. In conclusion, despite successful suppression of metabolic activity, in most cases benzimidazoles do not kill the parasite. PET is a reliable tool for assessing metabolic activity and for timely detection of relapses. Neither duration of treatment, kind of treatment, lesion size, calcifications, or regressive changes reliably indicate parasite death. We discourage the discontinuation of benzimidazoles in inoperable AE even after many years of treatment. However, patients with a poor compliance of benzimidazole intake or patients suffering from side effects to benzimidazoles might be assessed for PET negativity. If permanent discontinuation of benzimidazoles is attempted, the course of disease should be followed by PET. (HEPATOLOGY 2004;39:509–517.)

Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system)

OBJECTIVE Urinary tract (UT) dilation is sonographically identified in 1-2% of fetuses and reflects a spectrum of possible uropathies. There is significant variability in the clinical management of individuals with prenatal UT dilation that stems from a paucity of evidence-based information correlating the severity of prenatal UT dilation to postnatal urological pathologies. The lack of correlation between prenatal and postnatal US findings and final urologic diagnosis has been problematic, in large measure because of a lack of consensus and uniformity in defining and classifying UT dilation. Consequently, there is a need for a unified classification system with an accepted standard terminology for the diagnosis and management of prenatal and postnatal UT dilation. METHODS A consensus meeting was convened on March 14-15, 2014, in Linthicum, Maryland, USA to propose: 1) a unified description of UT dilation that could be applied both prenatally and postnatally; and 2) a standardized scheme for the perinatal evaluation of these patients based on sonographic criteria (i.e. the classification system). The participating societies included American College of Radiology, the American Institute of Ultrasound in Medicine, the American Society of Pediatric Nephrology, the Society for Fetal Urology, the Society for Maternal-Fetal Medicine, the Society for Pediatric Urology, the Society for Pediatric Radiology and the Society of Radiologists in Ultrasounds. RESULTS The recommendations proposed in this consensus statement are based on a detailed analysis of the current literature and expert opinion representing common clinical practice. The proposed UTD Classification System (and hence the severity of the UT dilation) is based on six categories in US findings: 1) anterior-posterior renal pelvic diameter (APRPD); 2) calyceal dilation; 3) renal parenchymal thickness; 4) renal parenchymal appearance; 5) bladder abnormalities; and 6) ureteral abnormalities. The classification system is stratified based on gestational age and whether the UT dilation is detected prenatally or postnatally. The panel also proposed a follow-up scheme based on the UTD classification. CONCLUSION The proposed grading classification system will require extensive evaluation to assess its utility in predicting clinical outcomes. Currently, the grading system is correlated with the risk of postnatal uropathies. Future research will help to further refine the classification system to one that correlates with other clinical outcomes such as the need for surgical intervention or renal function.

Whole-body MRI in children: Current status and future applications

Whole-body MRI (WBMRI) is a novel technique that makes imaging of the whole patient in a manner similar to scintigraphy or positron emission tomography (PET) possible. Unlike the latter two methods, it is without exposure to radiation and thus gaining increasing importance and application in pediatrics. With the introduction of a moving tabletop, sequential movement of the patient through the magnet has become possible with automatic direct realignment of the images after acquisition. The common scan plane is coronal with additional planes being added depending on the indication. WBMRI is targeted for maximum coverage of the body within the shortest possible time using the minimum number of sequences. The evaluation of the bone marrow has been the primary indication thus inversion recovery sequences like STIR or TIRM are mostly used with the T1-weighted sequence being added variably. For correct evaluation of the bone marrow in the pediatric age group understanding normal pattern of marrow transformation is essential. The primary role of WBMRI has been in oncology for the detection of tumor spread and also for the follow-up and evaluation of complications. The initial comparative studies of WBMRI with scintigraphy and PET in children have shown the high diagnostic potential of WBMRI. Emerging potential applications of WBMRI include the evaluation for osteonecrosis, chronic multifocal recurrent osteomyelitis, myopathies, and generalized vascular malformations. Future use of WBMRI may incorporate non-accidental trauma, virtual autopsy, body fat mapping and diffusion-weighted imaging.

Chronic recurrent multifocal osteomyelitis: what is it and how should it be treated?

Background Chronic recurrent multifocal osteomyelitis (CRMO) is the most severe form of chronic nonbacterial osteomyelitis. In children and adolescents, chronic nonbacterial osteomyelitis predominantly affects the metaphyses of the long bones, but lesions can occur at any site in the skeleton. Other organs (the skin, eyes, gastrointestinal tract and lungs) can also be affected. Clinical diagnosis is often difficult because the symptoms and course of disease vary significantly. We present a 10-year-old girl diagnosed with CRMO involving several vertebrae, the femur and the metatarsus.Investigations Physical examination, abdominal ultra sonography, conventional X-ray, MRI, technetium bone scan, esophagogastroduodenoscopy, colonoscopy, tests for HLA-B27 and thiopurine methyltransferase, polymerase chain reaction and thoracic vertebral bone biopsies.Diagnosis CRMO and Crohns disease.Management The patients condition improved whilst being treated with NSAIDs for 3 months; however, the patient had an allergic skin reaction to this therapy. Treatment was switched to sulfasalazine, accompanied by 3 weeks of therapy using oral prednisone, but sulfasalazine was discontinued 2 months later because the patient exhibited a minor elevation in the levels of liver enzymes. The patient was free of musculoskeletal symptoms for 6 months, at which time she started to complain again about pain in her back and bowel. Multimodal therapy, consisting of mesasalazine, corticosteroids (budesonide) and azathioprine, induced clinical remission of Crohns disease.

Imaging recommendations in paediatric uroradiology

The imaging and procedural recommendations as elaborated by the ESPR Paediatric Uroradiology Taskforce and the ESUR Paediatric Uroradiology Working Group were presented and discussed at the first uroradiology panel held during the ESPR Annual Congress in Barcelona in 2007. These recommendations were published in this journal [1] and have gained wide acceptance throughout Europe and beyond. A few imaging algorithms have been newly proposed by group members, partially completing the existing recommendations, and further important recommendations have been added. The imaging algorithm for prenatally diagnosed hydronephrosis (HN) has been supplemented by a statement on imaging neonates with fetally diagnosed high-grade HN and suspected posterior urethral valves (PUV). Recommendations referring to imaging children with suspected obstructive uropathy, the imaging algorithm for childhood haematuria, and the imaging algorithm for children with suspected urolithiasis have been formulated. The aim was again to reduce invasive and unnecessary investigations wherever possible without running the risk of missing potentially damaging conditions and increasing patient morbidity. As with the existing algorithms, the new proposals are consensus-based recommendations since little Pediatr Radiol (2009) 39:891–898 DOI 10.1007/s00247-009-1233-6

Combined static-dynamic MR urography for the simultaneous evaluation of morphology and function in urinary tract obstruction. II. Findings in experimentally induced ureteric stenosis.

Purpose. To assess the diagnostic value of combined static-dynamic MR urography (MRU) for the functional-morphological evaluation of experimentally induced urinary tract obstruction in the piglet. Materials and methods. In 20 piglets unilateral ureteric stenosis was created operatively. Post-surgery repeated comparative examinations were obtained with MRU, diuretic renal scintigraphy (DRS), excretory urography (EU) and ultrasound (US). MRU was performed as a combination study with a static 3D-IR-TSE sequence and a dynamic 2D-FFE sequence after Gd-DTPA with frusemide administration. Results. MRU allowed complete depiction of the prestenotic urinary tract and of the stenosis in all cases. In 43 comparative studies MRU was superior to EU in 36, EU to MRU in 2. When single kidney function was calculated with both MRU and DRS, results were highly correlated (r = 0.92). When urinary excretion was compared, significant agreement was achieved with concordant findings in 86 % and slightly discordant results in 12 %. Conclusions. Static-dynamic MR urography permits excellent depiction of experimentally induced urinary tract obstruction in piglets and reliable assessment of individual renal function and urinary excretion. Two advantages of the method stand out – it does not require radiation and it permits functional-morphological correlation.

Diagnostic Reference Ranges for Pediatric Abdominal CT

PURPOSE To develop diagnostic reference ranges (DRRs) and a method for an individual practice to calculate site-specific reference doses for computed tomographic (CT) scans of the abdomen or abdomen and pelvis in children on the basis of body width (BW). MATERIALS AND METHODS This HIPAA-compliant multicenter retrospective study was approved by institutional review boards of participating institutions; informed consent was waived. In 939 pediatric patients, CT doses were reviewed in 499 (53%) male and 440 (47%) female patients (mean age, 10 years). Doses were from 954 scans obtained from September 1 to December 1, 2009, through Quality Improvement Registry for CT Scans in Children within the National Radiology Data Registry, American College of Radiology. Size-specific dose estimate (SSDE), a dose estimate based on BW, CT dose index, dose-length product, and effective dose were analyzed. BW measurement was obtained with electronic calipers from the axial image at the splenic vein level after completion of the CT scan. An adult-sized patient was defined as a patient with BW of 34 cm. An appropriate dose range for each DRR was developed by reviewing image quality on a subset of CT scans through comparison with a five-point visual reference scale with increments of added simulated quantum mottle and by determining DRR to establish lower and upper bounds for each range. RESULTS For 954 scans, DRRs (SSDEs) were 5.8-12.0, 7.3-12.2, 7.6-13.4, 9.8-16.4, and 13.1-19.0 mGy for BWs less than 15, 15-19, 20-24, 25-29, and 30 cm or greater, respectively. The fractions of adult doses, adult SSDEs, used within the consortium for patients with BWs of 10, 14, 18, 22, 26, and 30 cm were 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9, respectively. CONCLUSION The concept of DRRs addresses the balance between the patients risk (radiation dose) and benefit (diagnostic image quality). Calculation of reference doses as a function of BW for an individual practice provides a tool to help develop site-specific CT protocols that help manage pediatric patient radiation doses.

Safety of contrast-enhanced ultrasound in children for non-cardiac applications: a review by the Society for Pediatric Radiology (SPR) and the International Contrast Ultrasound Society (ICUS)

The practice of contrast-enhanced ultrasound in children is in the setting of off-label use or research. The widespread practice of pediatric contrast-enhanced US is primarily in Europe. There is ongoing effort by the Society for Pediatric Radiology (SPR) and International Contrast Ultrasound Society (ICUS) to push for pediatric contrast-enhanced US in the United States. With this in mind, the main objective of this review is to describe the status of US contrast agent safety in non-cardiac applications in children. The five published studies using pediatric intravenous contrast-enhanced US comprise 110 children. There is no mention of adverse events in these studies. From a European survey 948 children can be added. In that survey six minor adverse events were reported in five children. The intravesical administration of US contrast agents for diagnosis of vesicoureteric reflux entails the use of a bladder catheter. Fifteen studies encompassing 2,951 children have evaluated the safety of intravesical US contrast agents in children. A European survey adds 4,131 children to this group. No adverse events could be attributed to the contrast agent. They were most likely related to the bladder catheterization. The existing data on US contrast agent safety in children are encouraging in promoting the widespread use of contrast-enhanced US.