Imaging of Peritoneal Dialysis Complications in Children.

Worldwide, peritoneal dialysis (PD) is the preferred renal replacement therapy option for children with end-stage renal disease who are awaiting transplantation. PD involves the instillation of a specifically formulated solution into the peritoneal cavity via a PD catheter, with two-way exchange of solutes and waste products along a concentration gradient. This exchange occurs across the peritoneal membrane. The PD catheter has intraperitoneal, abdominal wall, and external components. Enormous efforts have been directed to augment the efficiency and longevity of the peritoneum as a dialysis system by preventing PD-related infectious and noninfectious complications, which may otherwise result in technique failure and a subsequent temporary or permanent switch to hemodialysis. Imaging has an instrumental role in prompt diagnosis of PD complications and in guiding the management of these complications. The main imaging techniques used in the setting of PD complications-namely, conventional radiography, US, CT, MRI, and peritoneal scintigraphy-as well as the benefits and limitations of these modalities are reviewed. The authors also describe the frequently encountered radiologic findings of each complication. Familiarity with these features enables the radiologist to play a crucial role in early diagnosis of PD complications and aids the pediatric nephrologist in tailoring or discontinuing PD and transitioning to hemodialysis if necessary. Online supplemental material is available for this article. ©RSNA, 2022.

Non-Hodgkin Lymphoma Imaging Spectrum in Children, Adolescents, and Young Adults.

In children, adolescents, and young adults (CAYA), non-Hodgkin lymphoma (NHL) is characterized by various age-related dissimilarities in tumor aggressiveness, prevailing pathologic subtypes, and imaging features, as well as potentially different treatment outcomes. Understanding the imaging spectrum of NHL in CAYA with particular attention to children and adolescents is critical for radiologists to support the clinical decision making by the treating physicians and other health care practitioners. The authors discuss the currently performed imaging modalities including radiography, US, CT, MRI, and PET in the diagnosis, staging, and assessment of the treatment response. Familiarity with diagnostic imaging challenges during image acquisition, processing, and interpretation is required when managing patients with NHL. The authors describe potentially problematic and life-threatening scenarios that require prompt management. Moreover, the authors address the unprecedented urge to understand the imaging patterns of possible treatment-related complications of the therapeutic agents used in NHL clinical trials and in practice. Online supplemental material is available for this article. ©RSNA, 2022.

Doppler Parameters of the Hepatic Artery as Predictors of Graft Status in Pediatric Liver Transplantation.

OBJECTIVE: The purpose of this article is to determine whether hepatic artery (HA) Doppler parameters can be used to predict pediatric liver graft status in the immediate postoperative (< 10 days) period and in the first year after transplant. MATERIALS AND METHODS: A retrospective review of the liver transplant database was performed to review operative, clinical, laboratory, histopathologic, and ultrasound findings at three time points after surgery: 3 days, 3 months, and 1 year. The association between HA velocity and resistive index (RI) with graft status was assessed. RESULTS: Of 120 children (54 girls and 66 boys; mean age, 3 years 2 months) enrolled, 70 had satisfactory graft status at the 1-year follow-up examination. HA velocity of 50-200 cm/s at 3 days was associated with normal graft status during the immediate postoperative period (p = 0.003), at 3 months (p = 0.0653), and at the 1-year follow-up examination (p = 0.0268). Vascular and biliary complications in the immediate postoperative period were more frequent at an HA velocity of 201-300 cm/s (p = 0.0024). There was a significant association between RI at 3 days and graft status in the immediate postoperative period (p = 0.0308), with an RI less than 0.5 associated with vascular complications (p = 0.0116). CONCLUSION: An RI less than 0.5 is associated with vascular complications. An HA velocity of 50-200 cm/s and an RI of 0.5-0.8 are associated with normal graft status in children within the first year after transplant. Values outside this range, or in this range along with a constellation of other ultrasound findings and clinical status, support the initiation of additional more-specific investigations that may help in early treatment to prevent complications.

Utility of MR urography in children suspected of having ectopic ureter.

BACKGROUND: Conventional imaging modalities are limited in the assessment of complex lower urinary tract anomalies including ectopic insertion of ureters. MR urography can be useful in these situations. OBJECTIVE: To share our experience with MR urography in assessing lower urinary tract anomalies and to determine its accuracy in depicting ectopic ureters. MATERIALS AND METHODS: We conducted a retrospective review of all MR urography examinations done between November 2007 and March 2013 to note the presence or absence of duplex kidneys and insertion of ureters. We reviewed patient charts, surgical findings and results of other investigations including cystoscopy with retrograde ureterogram in order to establish presence or absence of ectopic ureter. This served as a reference standard against which we compared MR urography results. RESULTS: Of 22 MR urography examinations (3 boys, 19 girls; age range 3-16 years, mean 9.2 years) performed during the study period, 19 were performed to rule out ectopic ureters, two to assess complex anatomy and one to rule out crossing vessel in ureteropelvic junction obstruction. MR urography showed ectopic ureter in 9/19 children; one proved to be a false-positive. MR urography correctly showed normal insertion in 7/19 children. In the remaining 3/19 children distal ureter could not be seen, hence insertion was indeterminate on MR urography. One of these children had an ectopic ureter on cystoscopy and surgery. Statistical analysis showed MR urography's sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) to be 88.8-100%, 70-90%, 75-88.8% and 90-100% for the detection of ectopic ureter. CONCLUSION: MR urography is highly accurate in the assessment of ectopic ureters. In incontinent girls, MR urography should be the method of choice for depicting or ruling out ectopic ureter.

Characteristic scapular and rib changes on chest radiographs of children with ADA-deficiency SCIDS in the first year of life.

BACKGROUND: We describe radiographic changes in the ribs and scapulae seen in the first 6 months of life in children with ADA (adenosine deaminase) deficiency severe combined immundeficiency syndrome (SCIDS). We suggest that these changes are reversible with appropriate enzyme replacement therapy. OBJECTIVE: The purpose of this study was to describe characteristic rib and scapular radiographic changes in infants with ADA-deficiency SCIDS. MATERIALS AND METHODS: This was a retrospective review of chest radiographs of nine children with ADA-deficiency SCIDS performed in the first year of life by two experienced pediatric radiologists. A control cohort of unaffected children was used for comparison. RESULTS: All children with ADA-deficiency SCIDS manifested unusual scapular spurring and anterior rib cupping. None of the control children manifested these changes. CONCLUSION: Characteristic and reversible scapular and rib changes in the correct clinical setting should suggest an early diagnosis of ADA deficiency, prompting appropriate diagnostic and therapeutic measures.

Nasogastric tubes and videofluoroscopic swallowing studies in children.

BACKGROUND: Videofluoroscopic swallowing study (VFSS) is considered to be the gold standard method in assessing the risk of aspiration. Not infrequently, children who undergo VFSS are on tube feeds. OBJECTIVE: To investigate the reliability of the findings of VFSS when a nasogastric tube is in place at the time of the study. MATERIALS AND METHODS: A retrospective review of VFSS covered a 6.5-year period. This review included only patients who had studies performed both with and without a nasogastric tube in place. Ninety-two studies (46 with and 46 without a nasogastric tube) were assessed in 46 children (30 boys, 16 girls) with a mean age of 6.7 months. The VFSS checklist of findings included weak sucking, incoordination, nasopharyngeal reflux, valecular and pyriform sinus pooling, penetration, aspiration and associated cough or respiratory compromise. We compared the occurrence rates of these events between studies with and without a nasogastric tube. RESULTS: No significant statistical difference was found in the occurrence of the different swallowing events during VFSS in the two groups. The presence of a nasogastric tube does not significantly alter the association of cough; however, it shows a moderately significant (P=0.06) higher incidence of clinical respiratory compromise if aspiration does occur (8.5% of aspiration events). CONCLUSION: The presence of a nasogastric tube does not alter the findings of VFSS; however, it might increase the incidence of respiratory compromise when aspiration is present.

Imaging of ambiguous genitalia: classification and diagnostic approach.

Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. DSDs can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs; genitography is used to assess the urethra, vagina, and any fistulas or complex tracts; and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management.

Pediatric multifocal liver lesions evaluated by MRI.

OBJECTIVE: The purpose of this study is to present our experience with MRI evaluation of multifocal liver lesions in children and describe the MRI characteristics of these lesions. PATIENTS AND METHODS: A retrospective review of consecutive MRI exams performed for the evaluation of multiple liver lesions between 1 January 2007 and 31 December 2012 was done to note the number of lesions, the size of the largest lesion, MR signal characteristics, and background liver. Final diagnosis was assigned to each case based on pathology in the available cases and a combination of clinical features, imaging features, and follow-up in the remaining cases. RESULTS: A total of 48 children (22 boys, 26 girls; age between 3 months and 18 years with average age 10.58 years and median age 11 years) were included in the study. Totally 51 lesion diagnoses were seen in 48 children that included 17 focal nodular hyperplasia (FNH), 8 hemangiomas, 7 metastases, 6 regenerative nodules, 3 adenomas, 3 abscesses, and one each of angiomyolipoma, epithelioid hemangioendothelioma, focal fatty infiltration, hepatocellular carcinoma, hepatic infarction, nodular regenerative hyperplasia, and hepatic cyst. Background liver was normal in 33, cirrhotic in 10, fatty in 3, and siderotic in 2 children. Most FNH, hemangiomas, and regenerative nodules showed characteristic MRI features, while metastases were variable in signal pattern. CONCLUSION: Many commonly seen multifocal liver lesions in children have characteristic MRI features. MRI can help to arrive at reasonable differential diagnoses for multifocal liver lesions in children and guide further investigation and management.

Magnetic resonance imaging of congenital, inflammatory, and infectious soft-tissue lesions in children.

Magnetic resonance imaging has the advantages of multiplanar capability and high degree of tissue differentiation. It is useful for assessing the extent of soft-tissue abnormalities, such as vascular malformations, inflammatory and infectious processes, muscle disorders, and limb hypertrophy. Magnetic resonance imaging is sensitive to the presence of water and edema and is a good indicator for early diagnosis of inflammation and its level of activity. Fat-saturation techniques, including T2-weighted sequences and inversion recovery imaging, optimize diagnostic accuracy. T1-weighted images are good at defining the distribution and proportion of fat in the body, so they are useful in evaluating syndromes of the limbs, including vascular malformations, as well as lipoatrophy-lipodystrophy conditions. Magnetic resonance imaging provides guidance for efficient tissue biopsy. It allows comprehensive pretherapeutic assessment of soft-tissue vascular anomalies. It constitutes a good modality for following up the natural history of soft-tissue disorders during childhood.

Three-dimensional imaging of the spine using the EOS system: is it reliable? A comparative study using computed tomography imaging.

The aim of this study was to evaluate the precision of three-dimensional geometry compared with computed tomography (CT) images. This retrospective study included patients who had undergone both imaging of the spine using the EOS imaging system and CT scanning of the spine. The apical vertebral orientation was also measured using the EOS imaging system and by CT. Other measures such as the Cobb angle and apical vertebral rotation and translation were used as the control variables to evaluate the potential discrepancy between the standing position in EOS imaging and the supine position in CT scanning. The apical vertebral orientations were 8.7° for the first measurement and 8.4° for the second measurement made by the first author, and 10.3° for the measurement made by the second author. The average of these measurements was 9.3° compared with 6.6° (P=0.65) obtained on CT scanning. The precision of EOS-based measurements of vertebral rotation has never been tested in clinical practice. Although it has limitations, this study suggests that the results obtained using EOS are comparable to those obtained on CT.

Imaging of the inguinal canal in children.

The inguinal canal is often seen at the edge of the field of view on plain radiography, computed tomography, or magnetic resonance imaging and may often not be scanned when performing sonography of the scrotum or abdomen. As a result, pathology in this anatomical region may be easily overlooked. The peculiar embryology of the inguinal canal makes the identification of pathology in the inguinal region significant, as some of the processes that take place within the scrotum may originate in the abdomen, and vice versa. This article reviews the relevant embryology of the inguinal canal, discusses abdominal and scrotal conditions that involve the inguinal region, and illustrates associated pathology.

Fluid levels in pediatric imaging: a pictorial review.

Fluid levels appearances are not uncommon findings in different diagnostic modalities including radiography, ultrasound, computed tomography, and magnetic resonance imaging. The significance of such signs varies according to the involved sites and the clinical settings. Familiarity with their imaging features and their diagnostic value as well as their clinical implication are of paramount importance for the radiologist and the clinician. We aim to review a spectrum of examples of fluid levels encountered with different modalities in paediatric imaging and discuss their appearances and clinical significances.

Severe hypertelorism, midface prominence, prominent/simple ears, severe myopia, borderline intelligence, and bone fragility in two brothers: new syndrome?

We report on two brothers, born to double first cousin Jordanian Arab parents, with a syndrome comprising severe hypertelorism with upslanted palpebral fissures, brachycephaly, abnormal ears, sloping shoulders, enamel hypoplasia, and osteopenia with repeated fractures. Both have severe myopia, mild to moderate sensori-neural hearing loss and borderline intelligence. Results of chromosome analysis were normal as was a FISH assay for subtelomeric rearrangements. The father has mild hypertelorism but the family history is otherwise unremarkable. We think that this represents a previously unrecognized autosomal or X-linked recessive syndrome.

Abdominal manifestations of cystic fibrosis in children.

Pulmonary complications remain the main cause of mortality in cystic fibrosis, but the presenting symptoms in children are often related to gastrointestinal or pancreaticobiliary disease. Furthermore, abdominal manifestations are now seen throughout childhood, from infancy to adolescence. The child might present in the neonatal period with meconium ileus or its attendant complications. The older child might present with distal intestinal obstruction syndrome or colonic stricture secondary to high doses of pancreatic enzyme replacement. Less-common gastrointestinal manifestations include intussusception, duodenitis and fecal impaction of the appendix. Most children also show evidence of exocrine pancreatic deficiency. Radiologically, the combination of fat deposition and pancreatic fibrosis leads to varying CT and MR appearances. A higher than normal incidence of pancreatic cysts and calcification is also seen. Decreased transport of water and chloride also increases the viscosity of bile, with subsequent obstruction of the biliary ductules. If extensive, this can progress to obstructive cirrhosis, portal hypertension and esophageal varices. Diffuse fatty infiltration, hypersplenism and gallstones are also commonly seen in these patients. We present a pictorial review of the radiological appearance of these abdominal manifestations. The conditions are dealt with individually, together with typical appearances in various imaging modalities.