Early Vascular Aging in Children With Tuberous Sclerosis Complex.

Objectives: Experimental data indicate that activating mutations in the mTOR (mammalian target of rapamycin) pathway may lead to abnormal arterial wall structure. Vascular anomalies like arterial stenoses are reported in pediatric patients with tuberous sclerosis complex (TSC). In addition, large renal lesions (angiomyolipoma-AML and cysts) are risk factors for arterial hypertension in adult patients with TSC. This study aimed to assess blood pressure, including central blood pressure and arterial damage (early vascular aging-EVA) in children with TSC. Materials and Methods: In a group of 33 pediatric patients with TSC (11.13 ± 4.03 years, 15 boys, 18 girls), we evaluated peripheral and central office blood pressure, 24-h ambulatory blood pressure, and arterial damage: aortic pulse wave velocity (aPWV) [m/s], [Z-score], augmentation index (AIx75HR [%]), common carotid artery intima-media thickness (cIMT) [mm], [Z-score], stiffness of common carotid artery (E-tracking), renal lesions in magnetic resonance and ultrasonography, and selected biochemical parameters. The control group consisted of 33 healthy children (11.23 ± 3.28 years, 15 boys, 18 girls). Results: In TSC group 7 (21.2%) children had arterial hypertension, 27 (81.8%) children had renal angiomyolipomas, 26 (78.8%)-renal cysts, and 4 (12.1%) patients were treated with mTOR inhibitors (2 patients with everolimus and 2 patients with sirolimus) at the moment of evaluation. Children with TSC had higher central systolic blood pressure (AoSBP) (98.63 ± 9.65 vs. 90.45 ± 6.87 [mm Hg], p < 0.001), cIMT (0.42 ± 0.05 vs. 0.39 ± 0.03 [mm], p = 0.011), cIMT Z-score (0.81 ± 1.21 vs. 0.16 ± 0.57, p = 0.007), aPWV (4.78 ± 0.81 vs. 4.25 ± 0.56 [m/s], p = 0.003) and aPWV Z-score (-0.14 ± 1.15 vs. -0.96 ± 0.87, p = 0.002) compared to healthy children, without differences in AIx75HR (8.71 ± 15.90 vs. 5.24 ± 11.12 [%], p = 0.319) and stiffness of common carotid artery. In children with TSC AoSBP correlated positively with serum cystatin C concentration (r = 0.377, p = 0.030) and with maximum diameter of renal cyst (R = 0.419, p = 0.033); mean arterial pressure (MAP) 24 h Z-score correlated with serum cystatin C concentration (R = 0.433, p = 0.013); and aPWV Z-score with daily urinary albumin loss [mg/24 h] (R = 0.412, p = 0.029). Conclusions: Children with tuberous sclerosis complex are at risk of elevated central blood pressure and early vascular aging. In children with TSC, blood pressure and arterial stiffness are related to renal involvement.

Checklist for responsible deep learning modeling of medical images based on COVID-19 detection studies.

The sudden outbreak and uncontrolled spread of COVID-19 disease is one of the most important global problems today. In a short period of time, it has led to the development of many deep neural network models for COVID-19 detection with modules for explainability. In this work, we carry out a systematic analysis of various aspects of proposed models. Our analysis revealed numerous mistakes made at different stages of data acquisition, model development, and explanation construction. In this work, we overview the approaches proposed in the surveyed Machine Learning articles and indicate typical errors emerging from the lack of deep understanding of the radiography domain. We present the perspective of both: experts in the field - radiologists and deep learning engineers dealing with model explanations. The final result is a proposed checklist with the minimum conditions to be met by a reliable COVID-19 diagnostic model.

[Evaluation of renal lesions in children with tuberous sclerosis - summary of the first year of follow-up program]. / Ocena zmian w nerkach u dzieci chorych na stwardnienie guzowate ­ podsumowanie pierwszego roku programu opieki.

Tuberous sclerosis complex (TSC) is a genetic disease that leads to formation of tumors i.e. in brain kidneys, heart, lungs, and skin. AIM: The aim of the study was to summarize center's experience in the first year of program of nephrologic follow-up in patients with TSC. MATERIALS AND METHODS: During 12 months 30 children with TSC (14 boys and 16 girls aged from 3 months to 17 years 11 months, mean 7.57±5.02 years) were hospitalized. Following parameters were evaluated: genetic and biochemical tests, blood pressure in ambulatory blood pressure monitoring (ABPM), kidney lesions in ultrasonography (30 patients) and in magnetic resonance (14 patients). RESULTS: Genetic tests were performed in 6 children - in 5 TSC2 mutation was found, in one boy with TSC and numerous renal cysts only PKD1 mutation was revealed. Mean GFR was 130.81±23.23 mL/ min/1.73 m2. Four children (13.3%) had arterial hypertension. Renal lesions were found in 28 (93.3%) children: 18 patients had angiomyolipomas (AML) (mean diameter 15.4±12.5, max 38 mm), 23 patients had renal cysts (mean diameter 7.6±7.0, max 30 mm); 13 patients had AMLs and cysts. A dysplastic lesion (39x26x15 mm) in right kidney was found in one girl. Children with AML were older than remaining patients (10.08±4.55 vs. 4.25±3.50 [years], p<0.001). Children with cysts were characterized by higher systolic (p=0.017), diastolic (p=0.027) and mean (p=0.014) arterial pressure, and mean arterial pressure Z-score (p=0.025) in ABPM. Maximal kidney cyst diameter correlated positively with systolic, diastolic, mean arterial pressure, mean arterial pressure Z-score, and diastolic blood pressure load in ABPM (r = 0.61-0.75, p = 0.033-0.005). Two children with numerous AML with diameter >30 mm were treated with sirolimus. CONCLUSIONS: Because of common focal lesions in kidneys children with TSC should be kept under regular nephrologic follow-up. Presence of large renal cysts may predispose children with TSC to arterial hypertension.

Pyonephrosis as the first symptom of congenital hydronephrosis in a 6-year old girl.

Pyonephrosis in the course of hydronephrosis usually provides to total or near-total loss of renal function. In adults pyonephrosis usually results from urolithiasis. In children usually congenital urinary tract anomalies are present as contributing factors. CASE REPORT: 6-year old girl was admitted to the hospital because of 2-day history of high fever, abdominal pain, progressive deterioration of general condition and ultrasonographically (US) detected left hydronephrosis. US on admission showed grossly dilated left renal collecting system together with extensive echogenic debris and laboratory tests highly elevated inflammatory markers. Once diagnosis of pyonephrosis was established on the basis of clinical picture and US as well as laboratory tests results, nephrostomy tube was placed percutaneously. Pus culture obtained during placement of nephrostomy showed E.Coli ESBL (-) growth. Intensive antibiotic treatment (Meropenem) was continued for 3 weeks, nephrostomy was removed after 12 days after receiving normal urine. Further evaluation of urinary tract (US and computed tomography urography) showed large hydronephrosis due to ureteropelvic junction obstruction, while dynamic scintigraphy obstructive renogram with grossly diminished left kidney function to 20% of differential renal function. The girl was referred for operative treatment on urgent basis. Intraoperatively long distance utreteropelvic junction stenosis was found and dismembered Anderson- Hynes pyeloplasty was performed. During 2-years follow-up postoperatively US showed gradually decrease of dilatation of left renal collecting system, while dynamic scintigraphy revealed permanent improvement of drainage together with almost normal renal function (up to 45%). No urinary tract infections were noted. CONCLUSIONS: Proper management of pyonephrosis in hydronephrotic kidney due to congenital ureteropelvic junction obstruction enables good final result of treatment.

Testicular necrosis secondary to incarcerated inguinal hernia in male infants. Own observations.

One of the possible consequences of incarcerated inguinal hernia in boys is testicular ischemia because of the prolonged compression of spermatic cord structures by the sac contents, resulting in ipsilateral testicular atrophy. This complication is well described in the literature and occurs in 5-34% of patients. The incidence of testicular atrophy secondary to incarcerated hernia is estimated to be 2-3%. Testicular necrosis as the result of hernia incarceration is, however, an extremely rare clinical setting. We present 4 male infants aged 3-10 weeks with inguinal hernia incarceration which led to ipsilateral testicular loss. All the boys had to be operated on because of irreducible incarcerated hernia and in all the cases testicular necrosis was found intraoperatively. The time of incarceration before surgical intervention ranged from 4 to 12 hours (mean 6.75). Our data show that every case of hernia incarceration in a very young male infant requires rapid diagnosis and proper intervention, i.e. surgical treatment, instead of repeated attempts of manual reduction. Ultrasound examination should estimate not only blood flow through the incarcerated intestinal loop, but also through the ipsilateral testis. Moreover, during the operation of the incarcerated hernia in a boy it is necessary to estimate the ipsilateral testis.

Computed tomography urography with iterative reconstruction algorithm in congenital urinary tract abnormalities in children - association of radiation dose with image quality.

PURPOSE: To assess the extent to which a radiation dose can be lowered without compromising image quality and diagnostic confidence in congenital urinary tract abnormalities in children by using a CT scanner with an iterative reconstruction algorithm. MATERIAL AND METHODS: 120 CT urography image series were analysed retrospectively. Image series were divided into four study groups depending on effective radiation dose (group 1: 0.8-2 mSv; group 2: 2-4 mSv; group 3: 4-6 mSv; group 4: 6-11 mSv). Objective and subjective image quality were investigated. In objective analysis, measurements of attenuation and standard deviation (SD) in five regions of interest (ROIs) were performed in 109 excretory image series, and image noise was evaluated. In subjective analysis, two independent radiologists evaluated 138 kidney units for subjective image quality and diagnostic confidence. RESULTS: There were no significant differences in image noise in objective evaluation between the following study groups: 2 vs. 3 and 3 vs. 4 in all ROIs (with the only exception in spleen SD measurement between study groups 2 vs. 3), while there was significantly more image noise in group 2 in comparison to group 4. For all other ROIs in all study groups, there was more image noise on lower dose images. There were no significant differences in pairwise comparisons between study groups in subjective image quality. Diagnostic confidence was not significantly different between all study groups. CONCLUSIONS: Low-dose CT urography can be a valuable method in congenital urinary tract abnormalities in children. Despite poorer image quality, diagnostic confidence is not significantly compromised in examinations performed with lower radiation doses.

[High ureteral insertion as the cause of extreme hydronephrosis in a 5-year-old child with horseshoe kidney].

The incidence of horseshoe kidney is 1 per 400-800 live births. From 44-52% of the patients with horseshoe kidney have other coexisting abnormalities of the urinary tract, such as hydronephrosis, vesicoureteral reflux and a duplex collecting system. Our patient, a 5-year old boy, was admitted to a pediatric nephrology department because of abdominal pain and vomiting. He had ultrasonography of the abdomen performed for the first time at the age of 9-months and horseshoe kidney was shown. In a control ultrasonography, a mild dilatation of the pyelocalyceal system in the left kidney was described. On the day of admission, an abdominal ultrasound confirmed horseshoe kidney with large left hydronephrosis. Power Doppler ultrasonography showed two renal arteries to the left kidney and no arterial compression on the ureter. Dynamic scintigraphy (99mTc-EC) revealed left-sided hydronephrosis with high isotope intake up to 55% ERPF, a prolonged time of tissue perfusion and signs of subpelvic junction obstruction. Magnetic resonance urography presented an enlarged left kidney, with a diameter of up to 105 mm, a narrow renal cortex, a dilated renal pelvis up to 39 mm in diameter, dilated calyces up to 26-32 mm, and the high insertion of the ureter from the pelvis. The right kidney was normal. To facilitate drainage from the dilated collecting system of the left kidney, a double-J catheter was inserted. Pyeloplasty is planned as the next step of treatment. Conclusion: In a child with horseshoe kidney and a mild dilatation of the collecting system detected in infancy, long-term follow up is necessary, because of the increased risk of significant hydronephrosis in the future.

Influence of diuretic (furosemide) on contrast medium distribution in computed tomography urography of high-grade hydronephrosis in children.

INTRODUCTION: Diuretics improve visualization of the urinary tract in computed tomography urography in adults, as well as in magnetic resonance urography in adults and children. Also, diuretics can help to diagnose upper urinary tract obstruction in intravenous urography, ultrasonography or dynamic scintigraphy. However, there are still missing data on evaluation of furosemide usefulness in computed tomography urography examinations in children with suspected congenital anomalies of the urinary tracts.The aim of this study was to compare the homogeneity of contrast medium distribution in high-grade hydronephrosis in pediatric computed tomography urographies performed with and without use of diuretic (furosemide). MATERIALS AND METHOD: We have restrospectively analyzed computed tomography urography image series performed in the Department of Pediatric Radiology, in children with suspected congenital anomalies of the kidney and the urinary tract. Kidney units with high-grade hydronephrosis were divided in two groups: non-furosemide (n = 25) and furosemide (n = 28) group, where diuretic in dose 1 mg/kg, with maximum 20 mg, was administered intravenously 3-5 min before contrast medium administration. Subjective image quality and diagnostic confidence were evaluated by two independent radiologists and compared between study groups. RESULTS: There were no significant differences in subjective image quality and diagnostic confidence between furosemide and non-furosemide groups. CONCLUSIONS: Addition of furosemide to computed tomography urography does not improve homogeneity of contrast medium distribution in hydronephrotic kidneys in children.

Endoscopic correction of vesicoureteral reflux in children using polyacrylate-polyalcohol copolymer (Vantris): 5-years of prospective follow-up.

INTRODUCTION: The endoscopic correction of vesicoureteral reflux (VUR) in children is a currently well accepted therapy in many pediatric urology centers. Polyacrylate-polyalcohol copolymer (PPC), namely Vantris®, is one of the tissue-augmenting substances used for endoscopic reflux therapy. The aim of this study was to evaluate the results with PPC in children. MATERIAL AND METHODS: From 2012 to 2016, 125 children (73 girls and 52 boys) aged 0.6-17.9 years (mean 4.9 ±3.58) were treated with PPC. VUR was unilateral in 64 and bilateral in 61 patients, comprising 197 renal refluxing units (RRUs) grades: II in 72, III in 50, IV in 33 and V in 42. Of these primary reflux was present in 132 RRUs and 65 were complex cases. Voiding cystourethrogram (VCUG) was done 3 months after procedure. RESULTS: Follow-up was completed in 89.6% of patients (112 children), and 89.8% of RRUs (177 out of 197). Reflux resolved in 86.4% of RRUs after single injection, in 99.4% after second and in 100% after the third. The only significant, but serious complication observed was late ureteral obstruction after PPC injection correcting high grade reflux, which required ureteral re-implantation. This complication was found in 9 out of 112 children (8%), and in 11 out of 177 RRUs (6.2%), 1.1 -2.9 years (mean 2 ±0.7) after the PPC injection. The longest follow-up reaches 4.5 years. CONCLUSIONS: Our data show that the PPC injection is an effective procedure for treating all grades of VUR with high success rate. However, because of the possibility of late ureteral obstruction, which requires ureteroneocystostomy, long-term follow-up is mandatory.

Hepatic Portal Venous Gas in Children Younger Than 2 Years Old - Radiological and Clinical Characteristics in Diseases Other Than Necrotizing Enterocolitis.

BACKGROUND: Hepatic portal venous gas (HPVG) is a rare imaging finding in children. It can be an important manifestation of severe diseases such as necrotizing enterocolitis (NEC) in neonates or bowel wall rupture in older children. However, there are many other diseases presenting with HPVG that do not necessarily require a surgical intervention. CASE REPORT: In the period between 2011-2015, there were 12 cases of HPVG in children aged up to 24 months in our hospital. We did not include children with NEC. We retrospectively analyzed clinical data and US examinations as regards the suspected causes and final diagnoses. Only 1 patient with HPVG required an immediate surgical intervention. This was - a 4-month-old girl 32 days after a repair of a congenital diaphragmatic hernia, with ultrasound signs of acute bowel wall necrosis. During surgery a bowel strangulation was revealed. Other causes included: - 4 patients with bowel inflammation (including complications of neoplastic diseases such as leukemia and Hodgkins'disease); - 3 patients with food allergy; - 1 patient with acute gastroenteritis; - 1 patient with hepatic injury because of a suspected metabolic disease; - 1 incidental finding revealed before closing a ventricular septum defect; - 1 patient during follow-up performed 2 weeks after a reconstruction of bowel continuity. CONCLUSIONS: HPVG is not always a sign of a life-threatening condition and it should not be by itself an indication for surgical treatment. HPVG requires a close monitoring of the clinical status, which is crucial for further management. In patients in non-severe clinical condition, we propose to perform a follow-up ultrasound imaging within 1-2 days, and not to extend diagnostic procedures, especially in case of ultrasound picture normalization. An abdominal ultrasound examination appears to be the method of choice for the identification of gas in the hepatic portal system in children.

Double aorta artifact in sonography - a diagnostic challenge.

The double aorta artifact was described and studied thoroughly twenty-five years ago. Despite this, it is still not commonly known today and can cause diagnostic difficulty. Total aortic duplication can be considered an anatomic defect whilst partial duplication mimics aortic dissection. In the literature, this artifact has been compared with a very rare anomaly, i.e. the occurrence of two aortas in one patient. Currently, however, the differentiation of this artifact from abdominal aortic dissection seems to be of greater significance. The double aorta image occurs when ultrasound waves encounter prismatic fat tissue of the anterior abdominal wall. This artifact is more frequently observed in children and athletic young adults since the structure of this anatomic region in these individuals is conductive to the occurrence of this phenomenon. Moreover, it can be observed more often when curved transducers are used. Due to all these factors, an ultrasound beam undergoes greater refraction and make the artifact clearer. This phenomenon is usually easily recognizable and avoidable, but it sometimes might cause diagnostic difficulty. Obtaining an image of double abdominal vessels on ultrasound examination in transverse sections requires further inspection of the aorta in a different (sagittal) plane. This is not always possible due to poor patient preparation for scanning. Symmetrical flow on Doppler sonography is a typical feature of this artifact. Finally, magnetic resonance imaging or computed tomography can be considered to rule out a pathology.

[One-phase split-bolus CT Urography - a novel approach to reduce radiation dose in diagnostics of congenital anomalies of kidneys and urinary tract in children].

BACKGROUND: Low-dose CT Urography (LD-CTU) has become a standard procedure in urinary tract abnormalities in children, especially when MR Urography is not available. Standard one-phase CTU is performed in excretory phase. There is also a split-bolus technique, which combines two or even three phases during one scan and provides more clinical information without higher radiation exposure. It can be implemented for congenital anomalies of kidneys and urinary tract (CAKUT) in children, however, this application is not deeply discussed in scientific literature. Aim of this publication is to present the protocol and determine the role of LD-CTU in diagnostic imaging of CAKUT in children. MATERIAL AND METHODS: Close to 300 CTUs in children were performed as a standard of care during the last 6 years in our Department. Diagnostic accuracy in suspected CAKUT was analyzed, depending on applied protocol - standard excretory CTU, multiphase CTU and two different one-phase split-bolus CTU protocols. RESULTS: Visualization of the urinary tract was adequate in all study protocols. However, more clinically significant information was received in vascular-excretory protocol, including vascular and renal anatomy. Radiation exposure was similar or even lower than in other study protocols. CONCLUSIONS: One-phase split-bolus CTU protocol is a novel approach in low-dose diagnostic imaging of CAKUT in children. Combination of vascular and excretory phases has been shown as very effective technique, especially in comprehensive anatomical assessment of the abnormality and qualification to surgical intervention.

Ultrasonography of Extravaginal Testicular Torsion in Neonates.

BACKGROUND: Extravaginal testicular torsion (ETT), also called prenatal or perinatal, occurs prenatally and is present at birth or appears within the first month of life. It has different etiology than intravaginal torsion, which appears later in life. Testicular torsion must be taken into consideration in differential diagnosis of acute scrotum and should be confirmed or ruled out at first diagnostic step. Ultrasonography is a basic imaging modality, however diagnostic pitfalls are still possible. There is still wide discussion concerning management of ETT, which varies from immediate orchiectomy to conservative treatment resulting in testicle atrophy. MATERIAL/METHODS: In this article we present ultrasonographic spectrum of ETT in neonates, which were diagnosed and treated in our hospital during the last 8 years (2008-2015), in correlation with clinical and intraoperative findings. RESULTS: Thirteen neonates with ETT were enrolled in the study - 11 patients with a single testicle affected and 2 patients with bilateral testicular torsion. Most common signs on clinical examination were: hardened and enlarged testicle and discoloration of the scrotum. Most common ultrasonographic signs were: abnormal size or echostructure of the affected testicle and absence of the blood flow in Doppler ultrasonography. In 3 patients ultrasound elastography was performed, which appeared very useful in testicle structure assessment. CONCLUSIONS: Testicular torsion may concern boys even in the perinatal period. Ultrasonographic picture of acute scrotum in young boys may be confused. Coexistence of the abnormal size or echostructure of the torsed testicle with absence of the blood flow in Doppler ultrasonography appear as very specific but late ultrasonographic sings. Ultrasound elastography may be a very useful tool for visualisation of a very common clinical sign - hardening of the necrotic testicle.

Comparison of results of endoscopic correction of vesicoureteral reflux in children using two bulking substances: Dextranomer/hyaluronic acid copolymer (Deflux) versus polyacrylate-polyalcohol copolymer (Vantris).

BACKGROUND: Endoscopic correction of vesicoureteral reflux (VUR) in children offers minimally invasive management and is widely used as a first-line procedure for all grades of reflux. However, there is debate about which tissue-augmenting substance is the best to use. The aim of this study was to evaluate the efficacy of two bulking substances, Deflux (Dx/HA) and Vantris (PPC), for endoscopic treatment of VUR in children. METHODS: From 2009 to 2012, 65 children (50 girls and 15 boys) aged 1.45-9.9 years (mean 4.85 ± 2.52) underwent endoscopic correction of VUR using Deflux. VUR was unilateral in 31 patients and bilateral in 34 patients, comprising 108 renal refluxing units (RRUs) grades: II in 52, III in 47, IV in 7, and V in 2. From 2012, 68 children (43 girls and 25 boys) aged 0.6-17.9 years (mean 4.89 ± 3.46) were treated with Vantris. VUR was unilateral in 33 and bilateral in 35 patients, comprising 109 RRUs grades: II in 48, III in 29, IV in 13, and V in 19. Voiding cystourethrogram was done 3 months after procedure. RESULTS: All patients completed follow-up (summary Table). With Deflux, reflux resolved in almost 93% of RRUs after two procedures (in 63% after first injection), with Vantris, VUR was corrected in the same percentage after one procedure. DISCUSSION: The success rate with Deflux ranges between 68% and 92% (only 50-70% after single injection). The reported possibility of reflux recurrence after successful Deflux treatment, and the need for repeated injection led to introduction of the new substance Vantris. The results of a multi-centre survey published in 2014 showed that reflux is corrected in more than 90% of cases after single PPC injection. Our results with PPC confirm a high level of reflux resolution. CONCLUSIONS: Our data show that Vantris injection is a safe and effective procedure for treating all grades of VUR with good clinical outcome, and provides a higher and almost complete level of reflux resolution after first injection compared with Deflux.

Extreme hydronephrosis due to uretropelvic junction obstruction in infant (case report).

BACKGROUND: Hydronephrosis is the one of the most common congenital abnormalities of urinary tract. The left kidney is more commonly affected than the right side and is more common in males. AIM OF THE STUDY: To determine the role of ultrasonography, renal dynamic scintigraphy and lowerdose computed tomography urography in preoperative diagnostic workup of infant with extreme hydronephrosis. CASE REPORT: We presented the boy with antenatally diagnosed hydronephrosis. In serial, postnatal ultrasonography, renal scintigraphy and computed tomography urography we observed slightly declining function in the dilated kidney and increasing pelvic dilatation. Pyeloplasty was performed at the age of four months with good result. CONCLUSIONS: Results of ultrasonography and renal dynamic scintigraphy in child with extreme hydronephrosis can be difficult to asses, therefore before the surgical procedure a lower-dose computed tomography urography should be performed.

Ceftriaxone-associated acute gallbladder enlargement - an unexpected diagnosis in the child with urinary tract infection.

UNLABELLED: Biliary sludge and/or biliary pseudolithiasis occur in patients treated with ceftriaxone with prevalence of 3-57%. Biliary obstruction can be the cause of the acute gallbladder enlargement. It is a minor complication, that usually does not give clinical symptoms and resolves once the drug is discontinued. The authors present a case of a 5-month old boy treated for the acute pyelonephritis. Routine ultrasound, performed on the 5th day of treatment with ceftriaxone, showed gallbladder enlargement. In the consecutive studies small gallblader sludge was visible. Patient had no symptoms related to the gallbladder enlargement. Ultrasound performed 6 weeks from the drug discontinuation was completely normal. CONCLUSIONS: Patients treated with ceftroiaxone should be monitored for biliary sludge and pseudolithiasis.

Calyceal diverticulum of the kidney - diagnostic imaging dilemma in pediatric patients - case report.

BACKGROUND: Calyceal diverticula are rarely diagnosed in children. They can mimic other renal cystic lesions and correct diagnosis can be difficult to establish. Connection between fluid collection and collecting system confirmed by imaging studies is the key diagnostic finding. CASE REPORT: In this report we present a case of pediatric patient with calyceal diverticulum, with initial ultrasonographic diagnosis of simple renal cyst. Final diagnosis was established after extended diagnostics following infection of a fluid collection. CONCLUSIONS: 1. Differential diagnosis of well-circumscribed solitary renal fluid collections in children should include particularly: simple cyst, calyceal diverticulum and the first demonstration of ADPKD. 2. Diagnosis of calyceal diverticulum should be confirmed by contrast studies. 3. Standard management of calyceal diverticula in children includes ultrasonographic follow-up and conservative treatment and rarely requires surgical intervention.

Lower-dose CT urography (CTU) with iterative reconstruction technique in children - initial experience and examination protocol.

BACKGROUND: Conventional X-ray urography is one of the basic imaging techniques in urinary tract diseases in children. CT urography (CTU) employing standard Filtered Back Projection (FBP) reconstruction algorithms is connected with higher radiation dose. Advanced iterative reconstruction techniques enable lowering the radiation dose to the level comparable with conventional X-ray urography with better visualization of the urinary tract. Study protocol and indications for this modified technique should be discussed. MATERIAL/METHODS: Introduction of iterative image reconstruction techniques allowed to significantly reduce the radiation dose delivered during examinations performed at our Department, including CT examinations of urinary tract in children. During the last two years, CT urography replaced conventional X-ray urography and became the basic imaging technique in our Department. We discuss the study protocol regarding pediatric CTU examinations. The main goal is to receive an optimal image quality at reduced radiation dose. RESULTS: CTU examinations performed using the standard filtered back projection (FBP) reconstruction technique are associated with radiation doses about 1.5 times higher than those in conventional X-ray urography. Implementation of iterative reconstruction algorithms in advanced CT scanners allow to reduce the radiation dose to a level comparable or even lower than that in X-ray urography. In addition, urinary tract can be evaluated more precisely in multiplanar reformatted (MPR) and volume rendered (VR) images. CONCLUSIONS: 1. Advanced iterative reconstruction techniques allow to reduce radiation dose in CT examinations and to extend indications for CT urography in children. 2. Urinary tract can be evaluated more precisely in multiplanar reformatted and volume rendered images. 3. CTU may replace conventional X-ray urography in children.

Usefulness of lower-dose computed tomography urography with iterative reconstruction technique in diagnosis of congenital anomalies in urinary tract in children.

Introduction of iterative reconstruction technique in modern computed tomography allowed to reduce the radiation dose and to extend indications for computed tomography urography in children. We describe the case of boy with congenital anomalies in urinary tract including bilateral double collecting system, dilatation of double collecting system in the right kidney and dilatation of lower pelvis in left kidney and bilateral dilatation of ureters. Anomalies were detected in prenatal and then confirmed in postnatal ultrasonography. Voiding cystourethrograhy, which was performed on the 4th day of life revealed grade IV vesicoureteral reflux to the lower part of double collecting system in the right kidney and grade V vesicoureteral reflux to the left kidney. In cystoscopy posterior urethral valves were excluded and presence of double ureters was confirmed. Dynamic scintigraphy (99mTc-EC) detected impaired parenchymal secretory function in the lower pole of left kidney. The patient was qualified for surgical treatment including left lower heminephoureterectomy. Before surgery procedure computed tomography urography was performed and revealed congenital anomalies in urinary tract: bilateral double collecting system, bilateral hydronephrosis of the lower part of kidneys, dilatation of ureters associated with high grade of vesicoureteral refluxes, narrow cortex of left kidney. Computed tomography urography with iterative reconstruction techniques enables precise visualization of urinary tracts with reduced radiation dose. It replaces conventional X-ray urography because of much better visualization of urinary tracts with comparable or even lower radiation dose.