Anil G. Rao

Congenital lung anomalies in children and adults: current concepts and imaging findings.

This article presents the broad spectrum of congenital lung anomalies, which manifest both in childhood and can be first identified in the adult patient. Each lesion is described in terms of underlying cause, clinical presentation, imaging characteristics with emphasis on advanced cross-sectional imaging, and current treatment options. Up-to-date knowledge of currently available imaging studies and techniques as well as a clear knowledge of imaging characteristics of various congenital lung anomalies are essential for accurate diagnosis and optimal management.

Xanthogranulomatous pyelonephritis: an uncommon pediatric renal mass

Sir, We enjoyed reading the recent article of Smith et al. [1]. Even though xanthogranulomatous pyelonephritis (XGP) is uncommon in children, more than 265 cases have been reported in the literature [2]. The only uniqueness of this case is the patient’s young age of 3 years, as has been mentioned. XGP is diffuse in more than 90% of cases, as described. XGP is most commonly caused by Proteus mirabilis, as in this case report, or Escherichia coli infection. We feel that we could add to the literature by presenting our case of focal XGP in a 17-year-old girl caused by a relatively uncommon Enterococcus infection. The girl had a liver transplant when she was 2 years old for autoimmune hepatitis. She presented with nausea, vomiting, abdominal pain and a 22 kg weight loss over a 3-month period. She also had poorly controlled insulin-dependent diabetes mellitus and chronic transplant rejection. Two months prior to presentation, urine culture was positive for Enterococcus fecalis, which was treated with antibiotics. She was afebrile with negative urinalysis for infection at the time of presentation. To evaluate for hypertension and headaches on admission, renal sonogram was done which showed a focal hypoechoic hypovascular mass in the right kidney (Fig. 1). Since post-transplant lymphoproliferative disorder, lymphoma or other renal neoplasms were in the differential considerations along with atypical infection, a preand post-contrast-enhanced CT of abdomen and pelvis (DLP 761 mGy-cm, standardized for a 32-cm adult phantom) was done, which again showed a hypodense mass in the right kidney (Fig. 2). A core biopsy confirmed XGP (Fig. 3). A renal biopsy culture was positive for Enterococcus fecalis. This patient was successfully treated by conservative management with antibiotics, which is also very uncommon since most patients are managed with nephrectomy. The patient died 2 years later from other complications and on autopsy, the XGP lesion in the right kidney had resolved. In summary, XGP has to be considered in the differential diagnosis in a pediatric patient of any age

Gadolinium-based contrast agents in pediatric magnetic resonance imaging

Gadolinium-based contrast agents can increase the accuracy and expediency of an MRI examination. However the benefits of a contrast-enhanced scan must be carefully weighed against the well-documented risks associated with administration of exogenous contrast media. The purpose of this review is to discuss commercially available gadolinium-based contrast agents (GBCAs) in the context of pediatric radiology. We discuss the chemistry, regulatory status, safety and clinical applications, with particular emphasis on imaging of the blood vessels, heart, hepatobiliary tree and central nervous system. We also discuss non-GBCA MRI contrast agents that are less frequently used or not commercially available.

Advanced imaging techniques in pediatric body MRI

While there are many challenges specific to pediatric abdomino-pelvic MRI, many recent advances are addressing these challenges. It is therefore essential for radiologists to be familiar with the latest advances in MR imaging. Laudable efforts have also recently been implemented in many centers to improve the overall experience of pediatric patients, including the use of dedicated radiology child life specialists, MRI video goggles, and improved MR suite environments. These efforts have allowed a larger number of children to be scanned while awake, with fewer studies being done under sedation or anesthesia; this has resulted in additional challenges from patient motion and difficulties with breath-holding and tolerating longer scan times. In this review, we highlight common challenges faced in imaging the pediatric abdomen and pelvis and discuss the application of the newest techniques to address these challenges. Additionally, we highlight the newest advances in quantified imaging techniques, specifically in MR liver iron quantification. The techniques described in this review are all commercially available and can be readily implemented.

Paraspinal tumoral calcinosis in a child with systemic sclerosis/myositis overlap

Sir, Pediatric rheumatological overlap syndromes may present with a variety of features manifesting before 16 years of age. Overlap syndromes often present with sclerosis of the skin, Raynaud phenomenon and involvement of the other systems often complicated by soft tissue calcinosis [1]. Calcinosis has been described as affecting 18–20% of children with diagnosed juvenile systemic sclerosis and related conditions [2]. Common imaging findings in juvenile systemic sclerosis include decreased soft tissue thickness over the distal phalanges, bone resorption in the ribs, clavicle, radius and ulna, and periarticular or subcutaneous calcinosis [3]. Soft tissue calcinosis with calcium hydroxyapatite deposition in the extremities is a common finding in adults with systemic sclerosis as well. Tumoral calcinosis occurs when calcinosis forms a tumor-like mass [4]. Paraspinal tumoral calcinosis has been reported in adults but, to our knowledge, has not been reported in children [5]. A 12-year-old girl presented to our rheumatology clinic for evaluation of a 2-year history of progressively worsening intermittent arthralgia involving the knees, ankles and wrists along with photosensitivity and rash, digital ulcers during the winter months, oral ulcers, Raynaud phenomenon, fatigue and dry eyes. She had previously been diagnosed with lupus and was being treated with hydroxychloroquine (Plaquenil). She also had gastroesophageal reflux with esophageal stricture and dysmotility. Findings included sclerodermatous features in the extremities with increased serum aldolase, creatine kinase and positive antinuclear antibody test with a speckled pattern (1:80 titer). Smith, RNP, SS-A (Ro), SS-B (La) autoantibodies, scleroderma-specific Scl-70 and RNA Polymerase III antibodies were negative. HRCT of the lungs (DLP 325 mGy.cm, standardized for a 32-cm adult phantom) showed ground-glass opacities involving all lobes, slightly more in the right upper lobe with areas of honeycombing and minimal traction bronchiectasis with relative subpleural sparing (Fig. 1) consistent with a nonspecific interstitial pneumonia pattern. A dilated esophagus was also noted (Fig. 1). Well-defined paraspinal calcified densities consistent with tumoral calcinosis were seen predominantly adjacent to the posterior elements of several thoracic vertebrae and the lower cervical vertebra on both sides with bilateral neural foraminal involvement, most prominent at T3-4, T4-5 and T7-8 and T8-9 levels (Figs. 2 and 3). At the T7-8 level, the soft tissue calcification extended into the spinal canal causing mild canal narrowing with bilateral foraminal narrowing and also into the posterior paraspinal muscles (Fig. 3). At the C7-T1 level, there was involvement of the anterior paraspinal soft tissues as well (Fig. 4). The tumoral calcinosis was limited to the paraspinal location involving the adjacent soft tissues. She was diagnosed with systemic sclerosis/myositis overlap syndrome. Even though the child did not have neurological symptoms, the CT findings indicate she may be at risk N. Dray :A. G. Rao (*) Radiology and Radiological Science, Medical University of South Carolina, 96 Jonathan Lucas St., MSC 323, Charleston, SC 29425, USA e-mail: raoa@musc.edu

Pre-procedural scout radiographs are unnecessary for routine pediatric fluoroscopic examinations

BackgroundAlthough practice patterns vary, scout radiographs are often routinely performed with pediatric fluoroscopic studies. However few studies have evaluated their utility in routine pediatric fluoroscopy.ObjectiveTo evaluate the value of scout abdomen radiographs in routine barium or water-soluble enema, upper gastrointestinal (GI) series, and voiding cystourethrogram pediatric fluoroscopic procedures.Materials and methodsWe retrospectively evaluated 723 barium or water-soluble enema, upper GI series, and voiding cystourethrogram fluoroscopic procedures performed at our institution. We assessed patient history and demographics, clinical indication for the examination, prior imaging findings and impressions, scout radiograph findings, additional findings provided by the scout radiograph that were previously unknown, and whether the scout radiograph contributed any findings that significantly changed management.ResultsWe retrospectively evaluated 723 fluoroscopic studies (368 males and 355 females) in pediatric patients. Of these, 700 (96.8%) had a preliminary scout radiograph. Twenty-three (3.2%) had a same-day radiograph substituted as a scout radiograph. Preliminary scout abdomen radiographs/same-day radiographs showed no new significant findings in 719 (99.4%) studies. New but clinically insignificant findings were seen in 4 (0.6%) studies and included umbilical hernia, inguinal hernia and hip dysplasia. No findings were found on the scout radiographs that would either alter the examination performed or change management with regard to the exam.ConclusionPre-procedural scout abdomen radiographs are unnecessary in routine barium and water-soluble enema, upper GI series, and voiding cystourethrogram pediatric fluoroscopic procedures and can be substituted with a spot fluoroscopic last-image hold.

Renal myxoma in a pediatric transplant recipient

Renal myxoma is a very rare benign neoplasm seen almost exclusively in adults with only 16 reported cases in the literature. All of these cases have been reported in native kidneys with none being reported in a transplant kidney. We report the case of a renal myxoma in a 17-year-old boys transplant kidney that was found as an incidental mass on ultrasonography and further evaluated with CT and PET scans. PET findings of a renal myxoma are reported here for the first time, and imaging findings from previous cases are briefly reviewed. This case report highlights the fact that adult-predominant tumors and pathology should always be a consideration in pediatric patients who receive organ transplants from adult donors.

Fluoroscopy-guided placement of nasoenteral tubes in children using intermittent digital pulse fluoroscopy and last image save/grab technique

AIM To document the radiation exposure metrics, including fluoroscopic radiation time and radiation dose-area product, in children <18 years of age who undergo nasoenteral tube placement using fluoroscopic guidance with maximal dose-reduction techniques. MATERIALS AND METHODS Following institutional review board approval, the age, gender, anatomical information, immediate procedure-related complications if any, fluoroscopy time, and radiation dose-area product were collected retrospectively in all paediatric patients who underwent fluoroscopically guided nasoenteral tube placement during a 5-year period. Three paediatric radiology faculty members, a radiologist assistant, and trainee residents during their paediatric radiology rotation performed the procedures on two different digital fluoroscopic machines using radiation-minimising techniques. Median values of the fluoroscopy time and radiation dose-area product were calculated and compared to values reported in the literature using the Wilcoxon procedure. RESULTS There were 41 male and 33 female patients with a median age of 4 years and 6 months. Median fluoroscopy time used for placing a nasoenteral tube was 1.25 minutes with a median radiation exposure dose-area product of 0.245 Gy·cm(2). All patients had successful placement of nasoenteral tube without immediate procedure-related complications. CONCLUSION Fluoroscopy-guided nasoenteral feeding tube placement can be performed successfully with minimal radiation exposure without compromising procedural success.

Non-Central Nervous System Imaging of Pediatric Inflicted Injury

After dermatological findings such as bruises, contusions, and burns, fractures are the most common sequelae of non accidental trauma. This chapter will discuss the non-CNS radiological findings including soft tissue injuries, fractures, and visceral injuries of child abuse as well as the appropriate radiological investigations for their identification and documentation.

Cortical nephrocalcinosis in an infant caused by primary hyperoxaluria type 1

An 8-month-old boy was referred for an upper gastrointestinal study for vomiting. Scout abdominal radiograph shows bilateral cortical nephrocalcinosis (Fig. 1, arrows). US shows hyperechoic cortical rim with acoustic shadowing confirming cortical nephrocalcinosis (Fig. 2, arrows). Laboratory and genetic testing confirmed primary hyperoxaluria type 1 (PH-1). PH-1 is a rare autosomal-recessive disorder resulting from deficiency of the hepatic peroxisomal enzyme alanineglyoxylate aminotransferase, which causes excessive oxalate formation and calcium oxalate deposition in various organs. Kidneys show cortical or medullary nephrocalcinosis and recurrent urolithiasis causing progressive renal failure [1]. Skeletal manifestations of PH-1 sometimes result from oxalate deposition but more commonly result from chronic renal failure, leading to secondary hyperparathyroidism and renal osteodystrophy [2]. Findings include metaphyseal sclerotic lines and bands, lucent bands, cystic changes, permeative lucencies and vertebral diffuse or endplate osteosclerosis (rugger jersey appearance). Flat pelvic bones, carpal and tarsal bones, and patella might show a radiolucent rim.