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Background. Children with Beckwith-Wiedemann syndrome and idiopathic hemihypertrophy (BWS/HH) are at increased risk for developing Wilms tumor and screening with abdominal sonography is frequently recommended. However, there is a paucity of published data supporting this strategy. The purpose of this study was to determine whether sonographic screening at intervals of 4 months or less reduced the proportion of late-stage Wilms Tumor (WT) in children with BWS/HH. Procedure. A case series analysis was employed to compare the proportion of late-stage (stage III or IV) Wilms tumor in patients with BWS/HH who were screened with sonography (n = 15) to the proportion of late-stage Wilms tumor in unscreened patients with BWS/HH (n = 59). Patients were identified from the BWS Registry and from previously published studies. Screened patients had sonograms at intervals of 4 months or less. Results. None of the 12 screened children with Wilms tumor had late-stage disease, whereas 25 of 59 (42%) of unscreened children had late-stage Wilms tumor, a difference that was statistically significant (P < 0.003). Three children had false positive screening studies. They were operated on for suspected Wilms tumor but the lesions proved to be complicated renal cysts (n = 2) or nephroblastomatosis (n = 1). Conclusions. This study suggests that children with BWS/HH may benefit from screening sonograms at intervals of 4 months or less. However, false positive screening exams may result in unnecessary surgery. Given the rarity of BWS/HH, a larger, prospective international screening study is necessary to determine if the benefits of screening outweigh the risks.

MR imaging has become an indispensable tool in the evaluation of knee disorders. It is now widely relied on by clinicians, especially orthopedic surgeons, for guiding arthroscopic procedures and for staging tumor prior to resection. MR imaging has proved so successful that it has largely replaced arthrography in the evaluation of knee problems.

Objective In children with sickle cell disease (SCD), silent cerebral infarcts are the most frequent cause of neurologic injury. We determined the sensitivity and specificity of selective neurocognitive measures when separating children with silent cerebral infarcts and SCD from sibling controls. Additionally, we tested the validity of the same cognitive measures to identify patients with overt strokes. Methods We examined performance on a neuropsycho-logic battery containing measures of attention/executive, spatial, language, memory, and motor functioning for seven children with SCD and silent cerebral infarct, 21 children with SCD and overt stroke, and 17 normal siblings. Diagnosis of cerebral infarct was based on results of MRI. Results Measures from the attention and executive domains were the most useful for identifying children with silent cerebral infarct. The Test of Variables of Attention was the most robust measure and yielded a sensitivity rate of 86% and a specificity rate of 81%. This measure also showed a sensitivity rate of 95% in identifying overt stroke. Conclusions Brief cognitive screening measures, if properly constructed, may be an effective means of identifying children with silent cerebral infarct. Future prospective studies should be pursued to assess the utility of cognitive screening for silent cerebral infarcts in SCD.

Objective: Beckwith-Wiedemann Syndrome (BWS) is an overgrowth syndrome associated with macrosomia, omphalocele, macroglossia, visceromegaly and Wilms tumor (WT). We conducted a case-control study in children with BWS to examine whether nephromegaly increases the risk of WT. Methods: The BWS Registry was used to identify control and case patients. Control patients were defined as children with BWS who were older than 6 years and had no imaging evidence of renal disease or previous WT and for whom complete records were available; 31 patients met these criteria. Case patients were defined as children with BWS who had WT and screening renal imaging before the diagnosis of WT; 12 of these patients had serial screening images before diagnosis of WT and comprised the study population. Only renal images obtained before the diagnosis of WT was made were used to assess renal length. Results: All 12 patients with WT had nephromegaly (≥95th percentile of age adjusted renal length) on serial screening studies. Only four of 31 control patients (specificity = 86%) had nephromegaly resulting in an odds ratio of 72 (95% confidence interval = 13-391) for the risk of WT with nephromegaly. Conclusions: In patients with BWS, persistent nephromegaly is a strong risk factor for the development of WT. If screening for WT is done in this population, infants with nephromegaly should be considered those at greatest risk for WT, and screening may be best targeted at this group. (J Pediatr 1998;132:401-4) Dr. DeBaun is currently funded by the Robert Woods Johnson Minority Faculty Development Award.

OBJECTIVE. Our objective was to characterize the CT findings in children with acute appendicitis and to compare the CT appearance of the normal and abnormal appendix. MATERIALS AND METHODS. CT scans of 20 children (mean age, 8.6 years old) with surgically proven appendicitis were retrospectively reviewed. The CT studies were evaluated for the presence of a visualized appendix, appendiceal caliber and wall thickness, appendicoliths, pericecal inflammation, and abscess. Fifty children of similar age to the study group who did not have an appendicitis and who had undergone CT scans for acute trauma served as the control population. RESULTS. CT scans revealed the appendix in 25 (50%) of 50 control patients and in 11 (55%) of 20 patients with appendicitis. Appendiceal diameter ranged between 3 and 8 mm (mean, 6 mm) in the control group and between 8 and 12 mm (mean, 10 mm) in patients with appendicitis (p i) of 20 patients with appendicitis and in none of the control patients. Pericecal inflammation was seen in 19 (95%) of 20 patients with appendicitis and abscess was seen in 10 (50%) of 20 patients. Specific signs of appendicitis, defined as either an inflamed appendix or appendicolith with associated inflammatory changes, were seen in 16 (80%) of 20 patients. CONCLUSION. Our results suggest that CT findings of the healthy appendix are distinct from those of the abnormal appendix and that CT scans can be useful in diagnosing appendicitis in a pediatric population.

To assess effects of an automated kilovoltage selection tool on radiation dose, tube current, and image quality in pediatric contrast material-enhanced thoracoabdominal computed tomography (CT) and CT angiography.The institutional review board approved this retrospective study of 87 children (median age, 10.5 years; age range, 1 day to 19 years) who underwent thoracic CT, abdominal CT, or CT angiography with an automated kilovoltage protocol between November 2010 and July 2011. Volumetric CT dose index (CTDIvol) and milliamperage were compared with estimated prescanning calculations from a standard 120-kVp protocol. Image quality was subjectively scored on a scale of 1 to 5. In 15 patients who underwent scanning with both automated kilovoltage and standard 120-kVp protocols, image contrast and noise were quantitatively measured and the contrast-to-noise ratio (CNR) was calculated. Parametric and/or nonparametric testing of independent and/or paired samples was performed.Estimated median CTDIvol for all 87 studies was 4.8 mGy for the automated kilovoltage protocol versus 7.1 mGy for the 120-kVp protocol, yielding a 27% dose reduction (25% and 75% percentiles: 23% and 37%, respectively; P.001). The median milliamperage was 125.0 with the automated protocol and 87 with the 120-kVp protocol (P.001). Use of automated kilovoltage selection resulted in kilovoltage reduction from 120 kVp in 82 of the 87 patients (94%), with the percentage dose reduction greater for CT angiography than for chest CT (P.001). Reduction in kilovoltage showed a significant correlation with patient size (P.01). Diagnostic image quality was achieved in all patients. Mean contrast and noise were higher with the automated kilovoltage protocol than with the 120-kVp protocol (P ≤ .04), but CNRs for liver and portal vein were similar (P = .54 and .73, respectively).In pediatric CT and CT angiography, the use of automated kilovoltage selection technology significantly reduces radiation dose while maintaining image quality and CNR.

The tools available from MR imaging provide the pediatric radiologist great versatility in detecting and characterizing disease in children. An understanding of the strengths and limitations is essential for selecting the best technique to answer the clinical question in the shortest amount of time.

MR imaging provides an excellent morphologic depiction of the normal and abnormal liver. Although sonography remains the primary imaging technique used for detecting hepatic diseases, MR imaging is being used increasingly for characterization and staging of hepatic lesions. This article reviews the techniques of hepatic MR imaging in children and the MR appearance of neoplasms, parenchymal diseases, and vascular disorders in childhood.

By virtue of its ability to separate hematopoietic from fatty marrow, MR imaging is ideal for detecting marrow lesions. This article reviews the techniques of bone marrow imaging, interpretive pitfalls, anatomic variations with patient age, and the alterations in bone marrow signal occurring in a variety of pathologic conditions.

SUMMARY The use of MR imaging in thoracic diseases has increased with the development of newer scanners which provide faster scan times and improved image quality. Because of its high soft-tissue contrast and ability to detect flowing blood, MR imaging has significant advantages for assessing tissue characteristics and vascular pathologic conditions. Potential clinical applications of MR imaging include assessment of vascular anomalies, preoperative evaluation of mediastinal or chest wall tumor extent, differentiation of tumor versus fibrosis, and characterization of pleuroparenchymal diseases.

Obtaining information on transplanted lung microstructure is an important part of the current care for monitoring transplant recipients. However, until now this information was only available from invasive lung biopsy. The objective of this study was to evaluate the use of an innovative non-invasive technique, in vivo lung morphometry with hyperpolarized ³He MRI—to characterize lung microstructure in the pediatric lung transplant population. This technique yields quantitative measurements of acinar airways’ (alveolar ducts and sacs) parameters, such as acinar airway radii and alveolar depth. Six pediatric lung transplant recipients with cystic fibrosis underwent in vivo lung morphometry MRI, pulmonary function testing, and quantitative CT. We found a strong correlation between lung lifespan and alveolar depth—patients with more shallow alveoli were likely to have a negative outcome sooner than those with larger alveolar depth. Combining morphometric results with CT, we also determined mean alveolar wall thickness and found substantial increases in this parameter in some patients that negatively correlated with DLCO. In vivo lung morphometry uniquely provides previously unavailable information on lung microstructure that may be predictive of a negative outcome and has a potential to aid in lung selection for transplantation.

Feingold Syndrome: Microcephaly, Esophageal Atresia, Type III Laryngeal Cleft, Malrotation, Limb Anomalies

A proximal humeral articular surface from an ancient domestic dog deliberate burial was examined during survey of small mammal bones from a prehistoric early Late Woodland archeological site. An unusual lesion on the caudolateral articular surface prompted micro-computed tomography to define detailed structure. Results indicate cortical or immature woven bone arising subchondrally, replacing normal trabeculae, extending through a breach in the cortical surface, and having sharp transition with surrounding normal bone. Organized bone within the lesion indicates that the dog lived for months-to-years following insult. Differential diagnoses initially included: sharp penetrating trauma; intrinsic or extrinsic blunt fracturing force; osteochondrosis or complication of an osteochondral lesion; unusual osteoarthritis; and neoplasia. Computed tomography ruled out normal or unusual osteoarthritis, and neoplasia. The nature and small size of the lesion, relatively small size of the dog, and lack of evidence for complicating infection, suggest against sharp penetrating trauma as a sole cause. The most plausible differential diagnoses include: uncommon fracture-producing force in a companion animal, and blunt intrinsic or extrinsic force causing fracture at a weak point, such as an early osteochondral lesion, that was obliterated by healing. Combined gross examination, micro-computed tomography, and archeological-anthropological influences facilitated refinement of differential diagnosis.

Systemic artery-to-pulmonary artery shunts are palliative surgical procedures performed to increase the blood flow to the lungs for the relief of cyanosis and to enlarge the pulmonary arteries. Palliative procedures improve oxygen saturation, but they also can result in volume loading of the systemic ventricle and possible pulmonary hypertension.

Coronary artery anomalies represent a heterogeneous group of congenital disorders with different pathophysiology and clinical impact. By definition, they represent variants or deviations from the normal coronary artery anatomy [1].

Congenital absence of the pericardium is an abnormality characterized by a spectrum of findings ranging from a small defect to complete absence of the pericardium.

The heart lies in the middle mediastinum within the pericardial sac. The pericardial sac is formed by two layers: the outer layer known as the fibrous pericardium and the inner layer known as the serous pericardium. The serous pericardium contains two layers: visceral and parietal. The inner visceral layer covers the surface of heart and base of the great vessels. At the level of the great vessels, it reflects and becomes the parietal layer, which lines the thick fibrous pericardium. The fibrous pericardium fuses with the base of the great vessels and the diaphragm and it is attached to the sternum by the sternopericardial ligament.

The classic lesions of tetralogy of Fallot (TOF) include pulmonary stenosis, ventricular septal defect (VSD), overriding aorta, and right ventricular hypertrophy. The hemodynamically significant lesions are the VSD and pulmonary stenosis that results in right ventricular outflow tract (RVOT) obstruction. Originally, a two-stage repair was performed for repair of TOF. First pulmonary blood flow was increased with systemic-to-pulmonary artery shunts (classic and modified Blalock–Taussig shunt, Waterston shunt, or Potts shunt) followed by a complete repair when the child was older. Complications associated with this strategy include pulmonary hypertension and congestive heart failure from the augmented pulmonary blood flow and stenosis of the pulmonary artery at the anastomotic site.

Hypoplastic left heart syndrome (HLHS) is characterized by hypoplasia of the left heart and varying degrees of hypoplasia or atresia of the aortic valve and ascending aorta. It is included in the spectrum of conditions that can result in a cardiac circulation with a functionally single ventricle. Left untreated, HLHS is invariably lethal. Advances in palliative surgical procedures (Norwood procedure, bidirectional cavopulmonary shunt, modified Fontan procedure) have increased the survival rate in children with HLHS.

Univentricular heart, also termed “functionally single ventricle” and “single ventricle,” refers to the congenital heart defects in which the heart functionally has only one pumping chamber. The unifying criteria to identify a univentricular heart is a main (dominant) ventricle with a malformed atrioventricular connection and a rudimentary (incomplete) ventricle, which lacks an inlet component or less commonly an outlet component [1–4]. A true single ventricle is exceedingly rare.

The segmental, sequential, analytic approach was introduced by Van Praagh over 25 years ago [1–3]. This clinically useful approach is flexible and widely applicable to any imaging evaluation of congenital heart disease [4]. Using this logical approach, the morphologic features of the heart are determined sequentially by dividing the heart into three segments: visceroatrial situs or spatial arrangement (step 1), ventricular looping (step 2), and the spatial relationships of the great vessels (step 3). In step 4, the connections between the segments at the atrioventricular and ventriculoarterial levels are identified. Next, cardiac positioning is determined in step 5. Finally, step 6 involves the assessment for any associated malformation. See Fig. 5.1.

There are many not uncommonly seen variants that may be mistaken as abnormal, and recognition of these normal variants will increase diagnostic imaging accuracy and reduce the incidence of false alarms.

Until the mid-1990s, the standard surgical approach to repair congenitally corrected transposition of the great arteries was repair of the associated lesions (ventricular septal defect and pulmonary stenosis or atresia), allowing the right ventricle to remain as the systemic pump. Since this approach has a high prevalence of complications, surgical correction is now advocated in early childhood (several months to a few years of age). Correction is achieved with the double-switch procedure which uses a combination of the atrial switch and arterial switch surgeries previously described in Chaps. 23 and 24 [1–3]. Either a Mustard or Senning procedure is performed followed by either a Jatene switch or Rastelli-type procedure. The result of this operation is anatomically correct anatomy and removal of the systemic pressure load from the right ventricle. See Figs. 28.1 and 28.2.

Arterial switch (Jatene) procedure, which was developed in the late 1970s, is currently the method of choice for treatment of transposition of the great arteries (TGA). It reestablishes the left ventricle as a systemic pump, avoiding systemic ventricular failure associated with the atrial switch operation. This procedure is indicated for patients with TGA with an intact ventricular septum or with a small ventricular septal defect (VSD). Patients with large nonrestrictive VSDs, left ventricular outflow obstruction, or increased pulmonary vascular resistance may not be candidates for the arterial switch procedure.

The computed tomographic angiography (CTA) imaging protocol must be tailored to the suspected cardiac lesion and the type of prior surgical repair. The relevant parameters that need to be selected prior to imaging are contrast volume, contrast injection speed, the timing of the scan, slice collimation, scan length, tube voltage (kV), tube current (mA), and pitch. In addition, the imager must decide on the use of non-ECG-synchronized acquisition versus ECG synchronization (prospective or retrospective). In general, multidetector scanner with ≥64 rows is preferred for evaluation of congenital heart disease (CHD).

Aortic valve stenosis refers to a narrowing of the lumen of the aortic valve. It is the most common cardiac valvular condition requiring valve replacement. Congenital stenosis is the most common cause of aortic valve stenosis. It is usually associated with anomalous valves, most commonly the bicuspid aortic valve. The congenitally stenotic aortic valve also may be unicuspid (acommissural or unicommissural) or, rarely, congenitally quadricuspid/quadricommissural. A dysplastic tricuspid aortic valve can also develop stenosis (Fig. 13.1).

In a normal biventricular heart, the systemic and pulmonary circulations are in series and each circulation is supported by its respective ventricle. In patients with single ventricular chamber morphology, the two circulations are in parallel and patients only survive by mixing of the systemic and pulmonary venous blood, usually via a septal defect. Systemic venous to pulmonary artery surgical connections have been created to provide venous flow to the pulmonary circulation to allow oxygenation of the blood.

The Damus–Kaye–Stansel (DKS) operation is a palliative procedure for patients with a single functioning ventricle with an obstructed rudimentary outflow chamber. It is not used for treatment of hypoplastic left heart syndrome which is treated using the Norwood procedure. operation is used for in double-inlet left ventricle, tricuspid atresia with transposition of the great arteries (TGA), and a common atrioventricular canal with small left ventricular cavity.

Congenital pulmonary valve abnormalities encompass a spectrum of anomalies that result in right ventricular outflow tract (RVOT) obstruction. Based on the level of obstruction, there are three possible variants: (a) valvular, (b) subvalvular (infundibular stenosis), and (c) supravalvular.

Left ventricular noncompaction (LVNC), also called spongiform cardiomyopathy, is a rare congenital cardiomyopathy that results from interrupted cardiac embryogenesis. Pathologically, it is characterized by prominent trabeculations and deep intertrabecular recesses, creating a “spongy” myocardium. The cause is thought to be an arrest in the gradual compaction of the loosely interwoven meshwork of myocardial fibers during endomyocardial morphogenesis at 5–8 weeks of fetal life. The condition predominately affects the left ventricle (LV).

Tetralogy of Fallot (TOF) is characterized by four constant features: right ventricular outflow tract (RVOT) obstruction, malalignment (perimembranous) ventricular septal defect (VSD), biventricular origin of the aorta (overriding aorta), and right ventricular hypertrophy [1].

The development of multidetector computed tomography has resulted in marked advancements in the diagnosis of congenital heart disease (CHD) which has renewed interest in the classifications and definitions used to describe the anatomy of the heart and great vessels. The sequential, segmental approach to analyzing CHD patient images was introduced nearly three decades ago and is used worldwide [1–5]. Thus, a thorough understanding of both the nomenclature and anatomy applied in this approach is essential to the proper and error-free interpretation of CHD CTA images [6]. The definitions described below are based on the segmental, sequential approach to classifying CHD which is described in Chap. 5.

The first attempt to repair a patient with transposition of the great arteries (TGA) was performed by Senning who successfully constructed an atrial baffle in 1958 [1]. The procedure employed an atrial baffle created from autologous tissue to redirect caval blood to the left atrium which emptied into the left ventricle which then pumped the deoxygenated blood to the lungs. Pulmonary venous blood was redirected to the morphologic right atrium and through the tricuspid valve into the right ventricle which then filled the aorta with oxygenated blood. Subsequently, in 1964, Mustard introduced an atrial switch procedure utilizing prosthetic patch material to create an intra-atrial baffle (Figs. 23.1 and 23.2) [2, 3]. See Fig. 19.22 for a diagram of the uncorrected circulation and the circulation after the atrial switch procedure which normalizes the blood flow circuit.

Ebstein anomaly is a myopathy of the right ventricle that results in variable degrees of failure of delamination of the valve leaflets, leading to tricuspid valve regurgitation and right ventricular dysfunction. The classic pathology is apical (downward) displacement of the tricuspid valve leaflets (most frequently septal followed by posterior and anterior leaflets) with abnormal adherence of the leaflets to the underlying myocardium.