A pictorial review of the radiographic skeletal findings in Morquio syndrome (mucopolysaccharidosis type IV).

Morquio syndrome, also known as Morquio-Brailsford syndrome or mucopolysaccharidosis type IV (MPS IV), is a subgroup of mucopolysaccharidosis. It is an autosomal recessive lysosomal storage disorder. Two subtypes of Morquio syndrome have been identified. In MPS IVA, a deficiency in N-acetylgalactosamine-6-sulfate sulfatase interrupts the normal metabolic pathway of degrading glycosaminoglycans. Accumulated undigested glycosaminoglycans in the tissue and bones result in complications leading to severe skeletal deformity. In MPS IVB, a deficiency in beta-galactosidase results in a milder phenotype than in MPS IVA. Morquio syndrome presents a variety of clinical manifestations in a spectrum of mild to severe. It classically has been considered a skeletal dysplasia with significant skeletal involvement. However, the extraskeletal features can also provide valuable information to guide further work-up to assess the possibility of the disorder. Although the disease involves almost all parts of the body, it most commonly affects the axial skeleton, specifically the vertebrae. The characteristic radiologic findings in MPS IV, such as paddle-shaped ribs, odontoid hypoplasia, vertebral deformity, metaphyseal and epiphyseal bone dysplasia, and steep acetabula, are encompassed in the term "dysostosis multiplex," which is a common feature among other types of MPS and storage disorders. Myelopathy due to spinal cord compression and respiratory airway obstruction are the most critical complications related to mortality and morbidity. The variety of clinical features, as well as overlapping of radiological findings with other disorders, make diagnosis challenging, and delays in diagnosis and treatment may lead to critical complications. Timely imaging and radiologic expertise are important components for diagnosis. Gene therapies may provide robust treatment, particularly if genetic variations can be screened in utero.

Lung cyst and multinodular thyroid goiter: Keys to DICER1 syndrome diagnosis in a 16-year-old female.

Pulmonary cysts and neoplasms, especially congenital or occurring at a young age, should be thoroughly investigated. Evaluation for DICER1 mutations should be performed if there is a family history of this syndrome, the lung cyst/neoplasm is a pleuropulmonary blastoma, or other clinical manifestations of this syndrome are present or develop.

Safety and efficacy of gadoteric acid in pediatric magnetic resonance imaging: overview of clinical trials and post-marketing studies.

BACKGROUND: Gadoteric acid is a paramagnetic gadolinium macrocyclic contrast agent approved for use in MRI of cerebral and spinal lesions and for body imaging. OBJECTIVE: To investigate the safety and efficacy of gadoteric acid in children by extensively reviewing clinical and post-marketing observational studies. MATERIALS AND METHODS: Data were collected from 3,810 children (ages 3 days to 17 years) investigated in seven clinical trials of central nervous system (CNS) imaging (n = 141) and six post-marketing observational studies of CNS, musculoskeletal and whole-body MR imaging (n = 3,669). Of these, 3,569 children were 2-17 years of age and 241 were younger than 2 years. Gadoteric acid was generally administered at a dose of 0.1 mmol/kg. We evaluated image quality, lesion detection and border delineation, and the safety of gadoteric acid. We also reviewed post-marketing pharmacovigilance experience. RESULTS: Consistent with findings in adults, gadoteric acid was effective in children for improving image quality compared with T1-W unenhanced sequences, providing diagnostic improvement, and often influencing the therapeutic approach, resulting in treatment modifications. In studies assessing neurological tumors, gadoteric acid improved border delineation, internal morphology and contrast enhancement compared to unenhanced MR imaging. Gadoteric acid has a well-established safety profile. Among all studies, a total of 10 children experienced 20 adverse events, 7 of which were thought to be related to gadoteric acid. No serious adverse events were reported in any study. Post-marketing pharmacovigilance experience did not find any specific safety concern. CONCLUSION: Gadoteric acid was associated with improved lesion detection and delineation and is an effective and well-tolerated contrast agent for use in children.

Imaging features of juxtacortical chondroma in children.

BACKGROUND: Juxtacortical chondroma is a rare benign bone lesion in children. Children usually present with a mildly painful mass, which prompts diagnostic imaging studies. The rarity of this condition often presents a diagnostic challenge. Correct diagnosis is crucial in guiding surgical management. OBJECTIVE: To describe the characteristic imaging findings of juxtacortical chondroma in children. MATERIALS AND METHODS: We identified all children who were diagnosed with juxtacortical chondroma between 1998 and 2012. A single experienced pediatric radiologist reviewed all diagnostic imaging studies, including plain radiographs, CT, MR and bone scans. RESULTS: Seven children (5 boys and 2 girls) with juxtacortical chondroma were identified, ranging in age from 6 years to 16 years (mean 12.3 years). Mild pain and a palpable mass were present in all seven children. Plain radiographs were available in 6/7, MR in 7/7, CT in 4/7 and skeletal scintigraphy in 5/7 children. Three lesions were located in the proximal humerus, with one each in the distal radius, distal femur, proximal tibia and scapula. Radiographic and CT features deemed highly suggestive of juxtacortical chondroma included cortical scalloping, underlying cortical sclerosis and overhanging margins. MRI features consistent with juxtacortical chondroma included isointensity to skeletal muscle on T1, marked hyperintensity on T2 and peripheral rim enhancement after contrast agent administration. One of seven lesions demonstrated intramedullary extension, and 2/7 showed adjacent soft-tissue edema. CONCLUSION: Juxtacortical chondroma is an uncommon benign lesion in children with characteristic features on plain radiographs, CT and MR. Recognition of these features is invaluable in guiding appropriate surgical management.

CT in children's bones and joints: when, how and common findings.

Radiologic evaluation of musculoskeletal abnormalities in children is now usually performed by ultrasound and magnetic resonance imaging, owing to their excellent anatomic detail and lack of ionizing radiation. There remains a group of certain congenital and acquired conditions in which computed tomography (CT) can deliver invaluable information, and thus its application is justified in some pediatric patients. This article provides an overview of the most current imaging techniques for the latest generation of CTs, with particular emphasis on dose reduction. We also discuss the most important pathologic entities in which CT significantly contributes to the diagnostic workup or post-therapy follow-up.

Internal hernias in children: spectrum of clinical and imaging findings.

BACKGROUND: Internal hernias are uncommon in children and their clinical and imaging findings have not been widely addressed. OBJECTIVE: To determine the spectrum of clinical and imaging findings of internal hernia (IH) in children and to highlight diagnostic features. MATERIALS AND METHODS: Review of clinical, imaging and surgical findings in 12 children with surgically proven IH. RESULTS: IH found in seven girls and five boys. Five of the children were neonates and seven were between ages 8-17 years. All neonates presented acutely and had transmesenteric internal hernias (TMIH) (four congenital, one acquired). In the older children, five presented with chronic symptoms and two presented with acute symptoms; the former had paraduodenal hernias (all congenital) and the latter had a congenital pericecal and an acquired TMIH. Only 2/5 neonatal TMIH could be appreciated on GI contrast examination. All five paraduodenal hernias were easily diagnosed on UGI series. CT, in two older children, depicted a paraduodenal hernia and the acquired TMIH. In 7/10 (70%) congenital IH, there was associated malrotation (in all four right paraduodenal hernias). CONCLUSION: There is a wide spectrum of clinical and imaging findings of IH in children. TMIH were difficult to appreciate on GI contrast examinations, but paraduodenal hernias were easy to appreciate. One must have a high index of suspicion for right paraduodenal hernia if UGI series shows duodenum and proximal small bowel to the right of the spine.

Brown fat distribution in the chest wall of infants-normal appearance, distribution and evolution on CT scans of the chest.

BACKGROUND: While reviewing chest CT scans of infants, we repeatedly observed hyperdense enhancing tissue in the chest wall that is not well described in radiology literature. OBJECTIVE: This study was undertaken to describe the imaging features of this tissue in chest walls of infants. MATERIALS AND METHODS: CT scans of the chest conducted on all infants between April 2008 and October 2009 were retrospectively reviewed. CT studies with any deviation from normal radiation or contrast dose or those with chest wall anatomical distortion were excluded. RESULTS: One hundred eighty-eight infants were scanned, with 202 MDCTs, of which 180 (89.1%) received contrast agent. Fifty-four of 180 (30%) cases revealed focal areas of hyperdensity in various locations. All positive cases ranged between 2 days and 9 months of age. The areas of distribution of hyperdensity had excellent correlation with known areas of brown fat in the chest wall, known from nuclear medicine studies, and hence we concluded these to represent the same. CONCLUSION: Brown fat in the chest wall can be seen as enhancing tissue on contrast CT scans done on infants. This is a normal morphological component with the brown fat converting to normal fat. It is important to recognize it in the chest wall of infants to avoid misinterpretation.

Twenty classic hand radiographs that lead to diagnosis.

Most of the common skeletal dysplasias have some manifestation in the hand. Many have characteristic findings in the hand that lead to the diagnosis. Hand bones are also affected in many systemic hematologic and metabolic conditions. The diagnosis can be clinched on a single hand radiograph if characteristic findings are present. This pictorial essay illustrates characteristic findings of 20 common conditions including bone dysplasias and metabolic and hematologic abnormalities on a single hand radiograph. It also includes some common hand abnormalities without systemic skeletal abnormalities.

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.

Reliability of a standardized protocol to calculate cross-sectional chest area and severity indices to evaluate pectus excavatum.

PURPOSE: In evaluating the impact of surgical repair of pectus excavatum, the Haller index developed for preoperative decision-making purposes may be inadequate to quantify postoperative changes in shape of the chest. Individual patients may also have chest characteristics that impact the success of repair, many of which would be unlikely to be measured by the Haller index alone. We have developed a protocol that measures the cross-sectional chest area and the asymmetry index along with the Haller index to more completely quantify the nature of the deformity. The purpose of this study was to determine the reliability of this protocol in the interpretation of chest computed tomography images from multiple sites. The protocol was developed as part of a multicenter study of clinical outcomes after surgical repair of pectus excavatum. METHODS: Two radiologists independently selected 5 images from each of 32 computed tomography scans from multicenter study participants according to the protocol. A digitizer was used to measure the diameters and cross-sectional areas of the images selected; these results were used to calculate the Haller and asymmetry indices. The protocol was tested for intradigitizer and interradiologist reliability. Using the Haller and asymmetry indices, we also assessed agreement between radiologists classifying patients as abnormal. RESULTS: Agreement was uniformly high for all comparisons (all Lin's concordance coefficients >0.99 and all Cohen's kappa's >0.85, all agreement on classification of patients >95%) indicating almost perfect agreement. Disagreement on classification of patients using the Haller and asymmetry index was at the cut points for abnormality. CONCLUSION: The protocol was found to be a highly reliable method for deriving the cross-sectional area of the chest and the Haller and asymmetry indices and for classifying patients for surgical eligibility. Borderline cases should be examined carefully to determine the appropriateness of surgical intervention. Cross-sectional area can be measured reliably using this protocol and thus may be useful in quantifying the success of surgical intervention.

M-mode sonography of diaphragmatic motion: description of technique and experience in 278 pediatric patients.

BACKGROUND: The use of M-mode sonography for evaluation of diaphragmatic motion has only been previously reported in small series of children, and its use is not widespread among pediatric radiologists. OBJECTIVES: To present our experience with M-mode sonography in the evaluation of diaphragmatic motion in a large number of children with suspected diaphragmatic paralysis, to describe the technique used and to correlate sonographic findings with chest radiographs and clinical outcome. MATERIALS AND METHODS: Retrospective analysis of all M-mode sonograms performed in children from September 1999 to December 2003. The available chest radiographs and the clinical findings were reviewed and correlated with the sonographic findings. RESULTS: A total of 742 hemidiaphragms were evaluated in 278 children. There was no visualization of the left hemidiaphragm in 2 children (0.71%). Movement of the right hemidiaphragm was normal in 238 and abnormal in 131. Movement of the left hemidiaphragm was normal in 232 and abnormal in 135. Abnormal diaphragmatic movement was present in 118 (63%) of 187 children in whom chest radiographs had shown normal position of the hemidiaphragms. Follow-up examinations were obtained in 56 children, revealing improvement in diaphragmatic motion in 26, no change in 23 and deterioration of motion in seven. SUMMARY: M-mode sonography should be the modality of choice to assess diaphragmatic motion, as it can easily depict diaphragmatic dysfunction and allows comparison of changes in follow-up studies. Normal chest radiographs are poor predictors of normal diaphragmatic motion.

Awareness of genital health in young male athletes.

OBJECTIVE: To assess young male athletes' understanding of the need for a genital examination during the sports physical, their knowledge of signs and symptoms of serious testicular pathology, and the type of genital protection they wear for specific sports. Additionally, to identify common sport-specific genital injuries requiring emergency department treatment. DESIGN: Descriptive survey. SETTING: Station-based mass screening preparticipation physical exams performed in northeastern Ohio. PARTICIPANTS: A total of 755 male athletes at the junior high school, high school, and collegiate levels (age 12-25 years). MAIN OUTCOME MEASUREMENTS: Participants' answers to a 5-question survey. Male genital injury occurring in common contact and collision sports identified from the National Electronic Injury Surveillance System. RESULTS: Fifty percent did not understand why the genital examination is done. Forty-seven percent did not wear genital protection during sports. Most were unaware of the risk of testicular cancer and did not appreciate the difference in urgency of seeking medical treatment of painless versus painful testicular swelling. Approximately 20% of emergency department visits for sports-related genital trauma had a risk of permanent injury, and up to 7% resulted in hospitalization or transfer. CONCLUSIONS: Young male athletes are unaware of testicular pathology that affects their age group, and many do not wear genital protection during sports. Better education of young males regarding genital health and protection is necessary.

Fast STIR whole-body MR imaging in children.

Fast spin-echo short inversion time inversion-recovery (STIR) whole-body magnetic resonance (MR) imaging is an evolving technique that allows imaging of the entire body in a reasonable time. Its wide availability and lack of radiation exposure makes this method appealing for the evaluation of children. Since 2001, the authors conducted 140 pediatric whole-body MR imaging studies and correlated the findings with those from conventional imaging examinations. Bone marrow lesions, including marrow infiltration from lymphoma, metastases, and tumor-related edema, appeared with high signal intensity and were more easily detected on STIR images than with scintigraphy. Focal parenchymal lesions could be distinguished by their slightly different signal intensity, but pathologic lymph nodes could not be differentiated from normal nodes on the basis of signal intensity. The STIR technique is highly sensitive for detection of pathologic lesions, but it is not specific for malignancy; thus, the method cannot be used to differentiate benign conditions from malignant neoplastic lesions. Although fast STIR whole-body MR imaging permits evaluation of the entire skeleton and all viscera with a single examination, more experience and data are needed to determine its efficacy for staging neoplasms and assessing other multifocal disease in children.

Contrast enema depiction of small-bowel volvulus in complicated neonatal bowel obstruction.

About one-half of patients with meconium ileus (MI) present with a complication such as volvulus, atresia, meconium peritonitis or giant cystic meconium peritonitis. The treatment of these complications requires surgery. However, the preoperative diagnosis of complicated MI is difficult. We describe two neonates with complicated small-bowel obstruction, one with MI related to cystic fibrosis and the other not related to cystic fibrosis. In both, contrast enema depicted a spiral appearance of the distal small bowel, which at surgery proved to be the result of volvulus associated with antenatal bowel perforation. This appearance of the small bowel on contrast enema in this clinical setting has not been previously described. The recognition of this spiral appearance of the distal small bowel suggests the need for surgery.

Initial experience with FSE STIR whole-body MR imaging for staging lymphoma in children.

Our objective was to compare fast spin-echo (FSE) short inversion time inversion recovery (STIR) whole-body MR imaging with standard procedures in staging children with lymphoma. Eight children (age range, 2-16 years) underwent multi-station FSE STIR whole-body MR at initial staging (n=5) or for restaging following completion of therapy (n=5). Whole-body MR and conventional staging procedures, including CT (n=10), gallium-67 scintigraphy (n=9), bone scintigraphy (n=3) and bone marrow biopsy (n=7) were retrospectively compared for detection of sites involved by lymphoma and for the assigned stage. FSE STIR whole-body MR detected more sites of possible lymphomatous involvement at initial staging (87/88) and at restaging (5/5) than did conventional imaging (74/88, 3/5). MR was more sensitive than conventional imaging in detecting bone marrow involvement at initial staging. Following treatment, however, residual and therapy-induced bone marrow signal abnormalities could not be differentiated from lymphomatous involvement. Detection of nodal and visceral involvement correlated well. Our results suggest that FSE STIR whole-body MR imaging is a sensitive technique for evaluating lymphomatous involvement of bone marrow as well as non-marrow sites. Larger prospective trials are needed to determine if FSE STIR whole-body MR can replace standard radiographic procedures for initial staging and contribute in the follow-up of lymphoma in children.

Resolution of calcific brown fat necrosis associated with prostaglandin therapy for cyanotic congenital heart disease in neonates: report of two cases.

Prostaglandin E1 (PGE1) administration for palliation of cyanotic congenital heart disease in neonates has been associated with radiographically visible necrosis of brown fat about the neck and shoulder girdles. However, the natural history of this process has not been described. We present two patients with cyanotic congenital heart disease, treated preoperatively with prostaglandin E2 (PGE2), both of whom developed dramatic calcific brown fat necrosis. This process slowly resolved over time in both patients.

Long-term functional and anatomical follow-up of early detected spondylolysis in young athletes.

BACKGROUND: Spondylolysis defects detected by nuclear scintigraphy but not by plain radiographs represent early lesions. Functional outcome and eventual bony union of these defects are unknown. HYPOTHESIS: Defects with greater degree of healing shortly after treatment will proceed to full bony union and better long-term functional outcome. STUDY DESIGN: Longitudinal cohort study. METHODS: Forty young athletes with early detected spondylolysis (radiograph negative, nuclear scintigraphy positive) were divided into 3 stages of healing by computed tomography scan. Functional outcome was assessed 7 to 11 years later using the low back outcome score and other factors. Degree of bony healing was assessed in volunteers. RESULTS: Thirty-two of 40 subjects (80%) completed the survey. Twenty-nine of 32 (91%) had good or excellent low back outcome scores. None required spinal fusion, but 1 required partial diskectomy. Functional outcome did not differ based on initial computed tomography results. Radiographic follow-up was obtained in 11 volunteers. None of the 7 bilateral defects healed, and 3 of these progressed to grade 1 spondylolisthesis. All 4 unilateral defects healed fully with bone. CONCLUSIONS: Most young athletes conservatively treated for early spondylolysis maintain good functional outcome up to 11 years later. Unilateral defects can undergo full bony healing but may take longer than 12 weeks. Bilateral defects may undergo further degeneration and slip with time.

Age-related normal ranges for the Haller index in children.

PURPOSE: The Haller index is an accepted CT method for evaluating thoracic dimensions in patients with pectus excavatum. The purpose of this study is to establish age- and gender-related norms for the Haller index in childhood. MATERIALS AND METHODS: We retrospectively reviewed 574 consecutive chest CT examinations (M=285, F=289) performed at our institution from August 2001 through March 2002. Seventeen patients with a history of chest-wall deformity, trauma, or syndrome were excluded, for a total sample size of 557 patients. The Haller index was calculated for each patient, using electronic calipers. The sample population was then separated by gender and placed into 2-year age groupings. Two-way analysis of variance and Tukey's multiple comparisons were performed to determine significance at a=0.05. The least-square mean Haller index values for each age group and gender were calculated with 95% confidence intervals. RESULTS: In both males and females, the 0- to 2-year age group showed a significantly smaller mean Haller index than older children. In addition, females had significantly greater Haller index values than males in the 0- to 6- and 12- to 18-year age groups. CONCLUSION: The Haller index, a quantitative measurement of chest-wall configuration, demonstrates significant age- and gender-related variability. This should be considered when evaluating the patient with suspected chest-wall deformity.

Early Doppler changes in a renal transplant patient secondary to abdominal compartment syndrome.

Physiologic changes in renal transplant patients, such as transiently low central venous pressure, may be related to increased intra-abdominal pressure, from the volume of the transplanted kidney itself. Using intraoperative and postoperative Doppler ultrasound of the transplant renal vessels, we identified changes in flow dynamics following closure of the abdomen and reversal of the changes when the abdomen was reopened. This was attributed to abdominal compartment syndrome and a fasciotomy was created in the abdominal wall to accommodate the transplanted kidney. The findings in this case, in keeping with abdominal compartment syndrome, are not often considered in transplant recipients, but may explain some of the postsurgical physiology in some patients, particularly in the pediatric population.