Initial clinical experience with high-pitch dual-source CT as a rapid technique for thoraco-abdominal evaluation in awake infants and young children.

AIM: To evaluate dual-source high-pitch computed tomography (HPCT) imaging of the chest and abdomen as a rapid scanning technique to obtain diagnostic-quality imaging evaluation of infants and young children without sedation. MATERIALS AND METHODS: Fifty-three paediatric patients (age 24.1±2 months) who underwent chest or abdomen HPCT (≥1.5) and standard pitch CT (SPCT, <1.5) on a dual-source 128-row multidetector CT system were included in the study. Image quality assessment was performed by two paediatric radiologists for diagnostic confidence, image artefacts, and image noise. Objective image noise was measured. RESULTS: Most of the CT examinations were performed in children who were >1 year old (n=15 and n=20) followed by ≤1 year old (n=8 and n=10) in SPCT and HPCT, respectively. The mean radiation dose (SSDE) from HPCT was 1.96±1 mGy compared to 2.2±1 mGy for SPCT (p=0.3). No major artefacts were reported and overall image quality of all HPCT examinations was acceptable diagnostically. In addition, objective image noise values were not significantly different between HPCT compared with SPCT (11±3 versus 11±5, p=0.7). CONCLUSION: Ultra-fast, HPCT can be performed without the need for sedation as a potential alternative to anaesthetised magnetic resonance imaging in infants and young children.

Pulmonary hemorrhage in neonatal respiratory distress syndrome: Radiographic evolution, course, complications and long-term clinical outcomes.

BACKGROUND: Pulmonary hemorrhage (PH) is occasionally seen in premature infants after surfactant treatment for respiratory distress syndrome (RDS). These infants receive frequent chest radiographs (CXR) during and after hospitalization enabling long-term radiographic-clinical correlation. OBJECTIVE: To chart the natural evolution of CXR findings of PH in RDS and correlate radiographic patterns to supplemental oxygen requirement. MATERIALS AND METHODS: Retrospective review of clinical notes for gestational age (GA), birth weight (BW), intraventricular hemorrhage (IVH) and oxygen requirement were performed. CXRs were reviewed at 4 time-points; during PH, 28 days postnatal age, 36 weeks and at farthest available clinical follow-up. RESULTS: 18 infants born (2003-2016), GA (24-30 weeks); BW (482-1590 grams) were included. Mean onset of PH was 1.94 (0-5) days. 9/18 (50%) had IVH. 3 died during PH; all had IVH. During PH, CXR showed whiteout 9/18 (50%); patchy opacities 5/18 (27%); diffuse haziness 1/18 (6%) and no change 3/18 (17%). At 28 days postnatal age, CXR showed fine-interstitial (FI) markings 14/15 (93%) and whiteout 1/15 (7%). At 36 weeks,12/14 (85%) had FI and 2/14 (15%) developed cystic-interstitial changes. At farthest follow-up, FI 3/13 (23%); coarse-interstitial 4/13 (30%); peri-bronchial cuffing 5/13 (38%); normal 1/13 (9%) and the majority had hyperinflation 9/13 (69%). At discharge, 9/14 (64%) required home-oxygen and 5/14 (36%) were on room-air. At farthest follow-up, 6/14 (42%) required home-oxygen and 8/14 (58%) were on room-air. CONCLUSION: Premature infants that survive PH may later develop chronic lung disease of prematurity with an evolving interstitial pattern on CXR that clears overtime as they outgrow the need for supplemental oxygen.

Pediatric imaging: current and emerging techniques.

Imaging has always been an important component of the clinical evaluation of pediatric patients. Rapid technological advances in imaging are making noninvasive evaluation of a wide range of pediatric diseases possible. Ultrasound and magnetic resonance imaging (MRI) are two imaging modalities that do not involve ionizing radiation and are preferred imaging modalities in the pediatric population. Computed tomography (CT) remains the imaging modality with the highest increase in utilization in children due to its widespread availability and rapid image acquisition. Emerging imaging applications to be discussed include MR urography, voiding urosonography with use of ultrasound contrast agents, CT dose reduction techniques, MR enterography for inflammatory bowel disease, and MR cine airway imaging.

Imaging of child abuse.

Skeletal imaging plays a critical role in the diagnosis of abuse. High-detail radiographs of the entire skeleton, at times supplemented with nuclear imaging, CT, US, and MR imaging, elucidate the variety of findings with this entity. The radiologist's role includes careful analysis of clinical history, familiarity with typical osseous findings in abuse, and awareness of potential normal variants and pitfalls. An accurate diagnosis of abuse can then lead to appropriate measures to protect all family members at risk of serious injury.

Intraperitoneal rhabdomyosarcoma in children: incidence and imaging characteristics on CT.

OBJECTIVE: The purpose of this study was to determine the incidence and CT imaging features of intraperitoneal rhabdomyosarcoma in children. CONCLUSION: Approximately 10% of children with rhabdomyosarcoma may have intraperitoneal neoplastic involvement either at the time of diagnosis or subsequently. On CT, intraperitoneal rhabdomyosarcomas are associated with ascites, enhancing nodules, masses, a pseudomyxoma peritonei-like appearance, and omental caking.

Imaging of child abuse.

Diagnostic imaging plays a fundamental role in the evaluation of suspected physical abuse. Judicious application of modern imaging techniques to cases of suspected abuse aids in early and accurate diagnosis, leading to appropriate measures to protect all family members at risk of serious injury.

Fractures of the hands and feet in child abuse: imaging and pathologic features.

PURPOSE: To determine the imaging and histopathologic appearance of fractures of the hands and feet in abused infants. MATERIALS AND METHODS: The imaging findings in 11 abused infants with fractures of the hands and feet were examined retrospectively. All 11 infants underwent skeletal surveys; five infants also underwent nuclear bone scanning. Postmortem radiographs of the specimen and histopathologic data were available in two infants. RESULTS: A total of 22 fractures were noted. Six infants had fractures of the hands: six metacarpal and nine proximal phalangeal fractures. Five infants had fractures of the feet: six metatarsal fractures and one proximal phalangeal fracture. Torus fractures predominated, and these patterns were confirmed at the histologic examinations. These morphologic features were consistent with a mechanism of forced hyperextension. Oblique views of the hands and follow-up skeletal surveys aided in detection of these injuries. Four of six metatarsal fractures involved the first ray. Seven patients had three or more additional fractures that involved the long bones of the upper and lower extremities, and seven patients had additional fractures of the ipsilateral extremity. CONCLUSION: Fractures of the hands and feet are subtle but important injuries in abused infants. Well-collimated, high-detail radiographs of the hands and feet should be included in the skeletal survey performed for suspected child abuse.

Follow-up skeletal surveys in suspected child abuse.

OBJECTIVE: The purpose of this study was to assess the additional yield of a repeat skeletal survey in identifying and dating skeletal injury for cases in which child abuse was strongly suspected. MATERIALS AND METHODS: Twenty-three infants and toddlers strongly suspected of being physically abused on the basis of findings on the initial skeletal survey, other imaging studies, history, or physical examination underwent a follow-up examination approximately 2 weeks after the initial examination. The high-detail imaging system included a single-emulsion, single-screen combination with a low-absorption carbon-fiber cassette. The skeletal survey protocol entailed tightly collimated anteroposterior views of the appendicular skeleton and anteroposterior and lateral views of the axial skeleton. Between the two studies, all children were in Department of Social Services custody or living in a safe home. RESULTS: The follow-up skeletal survey yielded additional information regarding skeletal injury in 14 (61%) of 23 cases. Follow-up study increased the number of definite fractures detected from 70 to 89 (27%) (p = .005). Most of these additional injuries were classic metaphyseal lesions or rib fractures. In 13 of the 70 fractures previously detected, the follow-up skeletal survey also provided important information about the age of those injuries. CONCLUSION: When child abuse is strongly suspected on the basis of the findings on the initial skeletal survey, other imaging studies, history, or physical examination, a follow-up skeletal survey is recommended to provide a through and accurate assessment of osseous injuries.

Rib fractures in 31 abused infants: postmortem radiologic-histopathologic study.

PURPOSE: To examine the morphologic alterations of fractures of the lateral and anterior rib arcs and costochondral junction (CCJ) to better understand the factors that influence radiographic visualization and to gain insight into the mechanism of injury in rib fractures of abused infants. MATERIALS AND METHODS: Thirty-one infants (average age, 3 months) who died with inflicted skeletal injuries were studied with high-detail, pre- or postmortem skeletal surveys, or both, and radiography of specimens, with histologic analysis. The distribution and number of fractures were determined for each technique, and dating was performed on the basis of radiographic and histologic criteria. The radiologic features were correlated with the pathologic findings in comparable histologic sections. RESULTS: Of 165 fractures, 84 (51%) involved the ribs. Only 30 rib fractures (36%) were visible with skeletal survey examination. Lateral and anterior arc fractures tended to impact along the inner cortex of the rib. CCJ fractures tended to involve the inner aspect of the osteochondral interface with an associated osseous fragment. CONCLUSION: Acute and healing rib fractures are common in infants who died with inflicted injury; detection is technique-dependent. Use of high-detail skeletal radiography to identify these injuries in live and deceased infants appears justified.

The tailored low dose fluoroscopic voiding cystogram for familial reflux screening.

PURPOSE: Radionuclide voiding cystography is generally advocated as a screening study to detect familial reflux. We assessed the efficacy of tailored low dose fluoroscopic voiding cystography for this purpose. MATERIALS AND METHODS: We evaluated 10 boys and 10 girls 9 months to 10 years old (mean age 5 years) who were siblings of patients known to have reflux. The technique used a low dose fluoroscopic system. A tailored voiding cystographic protocol was designed to minimize gonadal radiation dose. RESULTS: Absence of reflux was confirmed in 10 patients. Mean fluoroscopy time was 19 seconds (range 14 to 22), resulting in mean gonadal radiation exposure of less than 1.5 mrad., which is comparable to the lowest reported doses with the radionuclide technique. After reflux was demonstrated in 10 patients the study was immediately converted to a standard fluoroscopic imaging technique to define lower tract anatomy and quantitate reflux, avoiding a second study. CONCLUSIONS: Tailored low dose fluoroscopic voiding cystography appears to be a practical approach for the assessment of familial reflux.

Localized pneumothorax with lobar collapse and diffuse obstructive airway disease.

Localized pneumothorax adjacent to a collapsed lobe has been reported in children with bronchial obstruction. We present our findings in seven children with a similar phenomenon occurring in association with diffuse obstructive airway disease. The children, aged from 3 weeks to 17 years, were admitted for diffuse obstructive airway disease and, subsequently, developed lobar collapse with adjacent localized pneumothorax. In five of the seven patients there was a paradoxical shift of the mediastinum toward the side of the pneumothorax. In six cases, the pneumothorax resolved spontaneously with lobar reexpansion. A conservative treatment approach to patients with this constellation of radiographic findings appears justified.

Distal humeral physeal injuries in child abuse: MR imaging and ultrasonography findings.

Distal humeral physeal injuries, in particular, fracture-separation of the distal humeral epiphysis, can be seen in abused infants. Detection of physeal injury in an infant or toddler may indicate the possibility of unsuspected abuse, particularly when an appropriate history explaining the circumstance of the fracture is lacking. In addition, the extent of injury can be difficult to characterize on plain radiographs. Ultrasonography (US) and MR imaging (MRI) may be of value in diagnosis and may obviate the need for intraoperative arthrography. We present MRI findings in three abused children with distal humeral physeal injuries. Sonographic correlation is also presented in one case.

MR imaging of benign fatty tumors in children: report of four cases and review of the literature.

This study correlates the magnetic resonance imaging characteristics with the pathologic findings in rare benign fatty soft tissue tumors in four children. A review of the literature is presented. Two cases of infiltrating lipoma displayed bright signal on both T1- and T2-weighted images, similar to that observed in subcutaneous fat. Histological study revealed extensive muscle infiltration by mature fat, with some areas of total fatty replacement. The case of facial lipomatosis revealed an extensive process of fatty invasion of adjacent soft tissue and osseous deformity by mass effect of the tumor. This lesion was bright on T1- and T2-weighted images. Histopathologic examination showed widespread invasion of squamous mucosa and skeletal muscle. The single case of lipoblastoma involved the presacral region and right buttock. This lesion, although bright on both T1 and T2 weighting, was relatively hypointense to subcutaneous fat on T1. Microscopic examination revealed a well-encapsulated fatty mass made up of cells ranging from lipoblasts to mature lipocytes. In childhood, when fatty lesions are almost always benign, a morphologic characterization by magnetic resonance may be sufficient basis on which to make critical therapeutic judgements.

Left-sided esophageal indentation in right aortic arch with aberrant left subclavian artery.

PURPOSE: To determine the structures responsible for the left-sided indentation in right aortic arch (RAA) with aberrant left subclavian artery (ALSA). MATERIALS AND METHODS: Magnetic resonance (MR) imaging was performed in five patients with RAA with ALSA in whom barium esophagography demonstrated a left-sided defect at the level of the aortic arch. RESULTS: In four patients, the aortic diverticulum (dorsal aortic root remnant) extended to the left of the esophagus, explaining the left-sided indentation. In one of those four patients, the ALSA contributed to this defect. In only one patient was no patent vascular structure identified to the left of the esophagus, and it was assumed that the ligamentum arteriosum alone produced this defect. CONCLUSION: The aortic diverticulum appears to be an important factor in the production of the left-sided esophageal defect in patients with RAA with ALSA.

Tailored low-dose fluoroscopic voiding cystourethrography for the reevaluation of vesicoureteral reflux in girls.

OBJECTIVE: Radionuclide voiding cystography is generally advocated for the reevaluation of proved vesicoureteral reflux. The purpose of this study was to assess the efficacy of tailored low-dose fluoroscopic voiding cystourethrography for this purpose. SUBJECTS AND METHODS: Forty-five girls (2 years 9 months to 19 years 7 months old; mean, 7.4 years) who had proved reflux were examined with tailored low-dose voiding cystourethrography. The technique used a low-dose fluoroscopic system and a computer-based video frame grabber that produced frame-averaged digital video fluoroscopic hard copies. A tailored voiding cystourethrographic protocol was designed to minimize ovarian radiation dose. Digital images were compared with standard 105-mm spot films in a similar group of 25 children. RESULTS: The tailored low-dose fluoroscopic technique produced diagnostically adequate images in all patients that were comparable in quality to standard spot films. The ovarian dose was 1.7-5.2 mrad (0.017-0.052 mGy) with a mean of 2.9 mrad (0.029 mGy). This compared favorably with the lowest reported doses with the radionuclide technique. CONCLUSION: Tailored low-dose fluoroscopic voiding cystourethrography is an attractive and practical alternative to the radionuclide technique in girls with proved vesicoureteral reflux.

Adrenal hemorrhage in abused children: imaging and postmortem findings.

OBJECTIVE: Adrenal hemorrhage associated with child abuse has received little attention in published reports. We review imaging studies or pathologic findings of adrenal hemorrhage in five cases of proved child abuse. SUBJECTS AND METHODS: The imaging findings in three children with adrenal hemorrhage were analyzed retrospectively. All three had abdominal CT scans and skeletal radiographs. One also had abdominal sonograms and MR images. The pathologic findings in two other abused children with adrenal hemorrhage who died of head injuries were also studied. In all five cases, a history of trauma was not initially known; child abuse was later confirmed. RESULTS: Unilateral hemorrhage in the right adrenal gland was found in all patients. Enhanced CT scans of the abdomen showed a low-attenuation, oval mass separating the limbs of the adrenal gland. Sonograms in one case showed a small, heterogeneous mass in the right adrenal gland. MR images obtained 3 weeks later showed an area of high signal intensity within the right adrenal gland on both T1- and T2-weighted images, consistent with subacute hemorrhage. In both deceased children, autopsy showed hemorrhage in the right adrenal gland, mainly within the medulla with some extension beyond the capsule in one case. All five children had associated abdominal visceral injuries or rib fractures or both, on the same side as the hemorrhage. CONCLUSION: Imaging findings of adrenal hemorrhage are similar to those previously described in patients with accidental trauma. Pathologic sections of the gland reveal predominantly medullary involvement with hemorrhage. The presence of adrenal hemorrhage in a child should prompt a search for other associated injuries and raise the possibility of unsuspected trauma.

Devices for transcatheter closure of intracardiac defects.

Transcatheter closure of intracardiac defects is an investigational procedure that is in use at a number of centers in North America and Europe. A radiologist should be able to recognize these devices on a chest radiograph, understand their actual physical appearance, and be able to recognize their expected location. This essay summarizes the indications for, technical aspects of, and radiologic appearance of these devices.

Urolithiasis in a children's hospital: 1985-1990.

We performed a retrospective study of patients who had urinary tract stones and were seen at our hospital from 1985-1990. The study was intended to determine the prevalence of urolithiasis and optimal approaches to imaging. Clinical data and imaging studies of 87 patients were reviewed. The mean age was 15.7 years with a range of 3 months to 44 years. Fifty-four percent of patients were male. Most patients had a known predisposing cause for urolithiasis; patients with myelodysplasia and structural urologic problems predominated. Plain films were performed in 77 patients; 57% showed stones. Ultrasonograms were performed in 71 patients; 77% showed stones. Excretory urograms (EU) were performed in 49 patients; 84% showed either stones or their effect on the urinary tract. Computed tomographic (CT) scan was performed in 25 patients; all showed stones.