Congenital diaphragmatic hernia in neonates: variations in umbilical catheter and enteric tube position

PURPOSE

To evaluate anatomic variations of support apparatus position on radiographs obtained in neonates with congenital diaphragmatic hernia (CDH).

MATERIALS AND METHODS

The authors evaluated radiographs obtained in 71 neonates with CDH to determine whether nasogastric tubes, umbilical venous catheters, and umbilical arterial catheters deviated from their expected anatomic course. The relationship between deviation patterns and hernia contents was evaluated.

RESULTS

Sixty-eight neonates-54 with left-sided CDH and 14 with right-sided CDH-had a nasogastric tube. The tubes in 21 patients with left-sided CDH had a normal anatomic course at radiography. Nineteen of these patients did not have stomach in the hernia. In 13 patients, the tip of the nasogastric tube was lodged at the esophagogastric junction. In 17 patients, the tube was in the left hemithorax. In all 30 of these patients, the stomach was within the CDH. All nasogastric tubes in the 14 patients with right-sided CDH had leftward deviation. Thirty-seven patients-27 with left-sided CDH and 10 with right-sided CDH-had umbilical venous catheters. The catheters in 12 patients with left-sided CDH had apex leftward convexity. The umbilical venous catheter in eight patients with right-sided CDH had rightward shift; all eight patients had liver herniation.

CONCLUSION

The positions of nasogastric tubes and umbilical venous catheters vary in several predictable patterns in neonates with CDH. Knowledge of these variations may be helpful for supporting the diagnosis of CDH in unclear cases and thus avoiding unnecessary apparatus adjustments, and for predicting hernia contents.

Marked acute tissue swelling following percutaneous sclerosis of low-flow vascular malformations: a predictor of both prolonged recovery and therapeutic effect

PURPOSE

To evaluate the significance of marked, acute swelling in patients after percutaneous sclerosis of low-flow vascular malformations, as a predictor of both prolonged recovery and likelihood of therapeutic effect.

MATERIALS AND METHODS

In 22 patients who underwent percutaneous ethanol sclerosis of low-flow vascular malformations, we compared the incidence of prolonged recovery and lasting therapeutic effect between those patients with and without marked soft-tissue swelling following the procedure.

RESULTS

Five patients exhibited marked swelling after sclerosis. Four of these five had causes of prolonged recovery. These four recovered and all five eventually had marked therapeutic effect. Seventeen patients did not meet criteria for severe swelling. Only one of these patients had prolonged recovery. Eighteen of the 22 total patients had therapeutic effect. All 4 of the 22 total patients who had no therapeutic effect were in the group without marked swelling.

CONCLUSIONS

Marked soft-tissue swelling, which occurs after percutaneous sclerosis of vascular malformations, is both a predictor of prolonged recovery and high likelihood of therapeutic effect.

Reduced frequency of sedation of young children with multisection helical CT

PURPOSE

To determine whether the use of multisection helical computed tomography (CT) can decrease the need for sedation compared with single-section helical CT.

MATERIALS AND METHODS

The number of children who required sedation to undergo body CT with a multisection helical scanner was recorded. The authors noted the type of examination and whether contrast material was used. The children were categorized according to age (< or = 17 years, < or = 6 years, < or = 1 year).

RESULTS

In 219 CT examinations, only three children required sedation (1.4%). The sedation rate was 3% (three of 90) for children aged 6 years or younger and 8% (three of 37) for those aged 1 year or younger. Examinations were of the chest, abdomen, and pelvis in 68 patients, of the abdomen and pelvis in 112, and of the chest alone in 39. Contrast material was intravenously administered in 186 (85%) examinations. All scans were of diagnostic quality.

CONCLUSION

The rate of sedation was reduced threefold with multisection helical CT compared with standard helical CT, and the need for sedation was eliminated in some age groups.

Novel techniques for MR imaging of pulmonary airspaces

Hyperpolarized gas- and molecular oxygen-enhanced MR imaging are two new techniques for high-resolution MR imaging of pulmonary airspaces. Both techniques produce excellent images in a safe, reproducible, and technically feasible manner. Because morphologic and functional information is obtained, and radiation is not used, these techniques may prove ideal for serially evaluating patients with a variety of lung diseases that affect pulmonary ventilation, such as cystic fibrosis, emphysema, asthma, or bronchiolitis obliterans syndrome in lung transplant recipients. At present, the greatest clinical experience is with hyperpolarized He-3-enhanced MR imaging. This technique is limited, however, by the limited availability of He-3, by its polarization requirements, and by the need to tune the MR system to the resonant frequency of the gas. There is less clinical experience with oxygen-enhanced MR imaging. Although this technique produces images with more inherent noise than hyperpolarized He-3 imaging, this problem can be overcome by signal averaging. Oxygen-enhanced imaging has the major advantages of lower cost and ready availability. For oxygen-enhanced imaging, the MR imaging system does not need to be readjusted; imaging is performed at the conventional hydrogen proton frequency.

Imaging of congenital vascular and lymphatic anomalies of the head and neck

Congenital lymphatic and vascular malformations and infantile hemangiomas can be combined under the heading of endothelial malformations. Based on their biologic behavior, endothelial malformations can be divided into two groups: infantile hemangiomas and vascular malformations. Vascular malformations can be subdivided into lymphatic, capillary, venous, and arteriovenous malformations. Often frightening for the patient and the patient's family, some endothelial malformations, however, will resolve; yet others can lead to long-term disfigurement and even can be fatal-due to airway obstruction, secondary infection, or exsanguination. When recognized early, however, the appropriate therapy, or watchful waiting, can be initiated, and the long-term physical and psychological consequences of these malformations can be minimized.

MR imaging of mediastinal masses

Although ongoing developments in MR imaging have resulted in improved image quality and decreased acquisition time, MR imaging is largely used as an adjunct to CT scanning in the evaluation of mediastinal abnormalities. In this role, MR imaging often provides additional information about the nature, location, and extent of disease. MR imaging is useful in confirming the cystic nature of mediastinal lesions that appear solid on CT and, by revealing small amounts of intralesional fat, can suggest the diagnosis of hemangioma, teratoma, or extramedullary hematopoesis. MR imaging is the preferred modality for imaging neurogenic tumors, because its multiplanar capability and high contrast resolution can best demonstrate the number and nature of the lesions (differentiating cysts from neoplasms), intraspinal extension, and craniocaudad extent. MR imaging is also especially useful for evaluating the mediastinum of patients for whom the administration of iodinated contrast material is contraindicated.

Thrombocytopenia and absent radii (TAR) syndrome associated with horseshoe kidney

The TAR syndrome is an inherited disorder characterized by limb abnormalities, especially absent radii, and hypomegakaryocytic thrombocytopenia. Previous reports have included two infants with genitourinary abnormalities. We report a newborn with bilaterally absent radii and foreshortened ulnae, hypoplastic humeri, a left clubfoot, a ventricular septum defect, and persistent thrombocytopenia. This constellation of abnormalities is consistent with the TAR syndrome. In addition, he had a horseshoe kidney with parenchyma of normal appearance. This is the first report of horseshoe kidney in association with the TAR syndrome.

Abnormalities of the chest wall in pediatric patients

A variety of focal processes and diffuse abnormalities are found predominantly in children. In addition, thoracic manifestations of trauma differ in children because of increased chest wall compliance. Familiarity with both these abnormalities as well as the common normal variations provides optimal imaging evaluation.

Correlation between findings on chest radiography and survival in neonates with congenital diaphragmatic hernia

OBJECTIVE

Predictors of survival are helpful when deciding on aggressiveness of care of neonates with congenital diaphragmatic hernia and respiratory failure. We evaluated findings on chest radiography as potential predictors of survival in these patients.

MATERIALS AND METHODS

Findings on chest radiographs of neonates less than 24 hr old with congenital diaphragmatic hernia were evaluated. Radiographic findings analyzed included percentage of aerated ipsilateral lung, percentage of aerated contralateral lung, mediastinal shift, and hernia contents. Each finding was compared with survival (equated with hospital discharge) using a Mantel-Haenszel chi-square test. Survival was also determined using the total number of poor prognostic findings present in any one patient.

RESULTS

In the 73 neonates with congenital diaphragmatic hernia in our study, the overall survival rate was 55%. There were statistically significant relationships between survival rate and percentage of ipsilateral aeration (p = 0.001), percentage of contralateral aeration (p = 0.016), and mediastinal shift (p = 0.026). The survival rate for multiple poor prognostic factors was 0% with four of four factors and 20% with three of four factors (p = 0.001). Survival rate was not influenced by prematurity (p = 0.102), sex (p = 0.104), or side of hernia (p = 0.895).

CONCLUSION

Findings on initial chest radiography are helpful in predicting survival in neonates with congenital diaphragmatic hernia.

Thoracic manifestations of neurofibromatosis-I

The intrathoracic manifestations of neurofibromatosis-I are protean and can, on occasion, mimic those of malignancy. Many of the intrathoracic findings are characteristic of the disease and can be expected to be present. Knowledge of the full spectrum of radiologic findings can thus be useful in preventing diagnostic error. Furthermore, an unexpected finding, such as rapid growth of a neural tumor, should be recognized as an atypical feature (suspicious for malignant degeneration) and result in further evaluation.

A pattern-oriented approach to splenic imaging in infants and children

The spleen in infants and children is commonly involved in a variety of pathologic processes. Some of these processes cause isolated splenic disease, whereas others involve the spleen as part of a systemic illness. To facilitate differential diagnosis of splenic abnormalities, a pattern-oriented approach to the imaging evaluation of the pediatric spleen was developed. With this approach, splenic anomalies are categorized as anomalies of splenic shape (clefts, notches, lobules), location (eg, wandering spleen), number (polysplenia, asplenia), or size (splenomegaly, splenic atrophy); solitary lesions (eg, cysts, lymphangiomas, hemangiomas, hamartomas); multiple focal lesions (eg, trauma, infection and inflammation, neoplasms, storage disorders); and diffuse disease without focal lesions (eg, infarction, heavy metal deposition, hemangioendotheliomas, peliosis). A variety of imaging modalities can be used in splenic assessment, including computed tomography, magnetic resonance imaging, ultrasound, and technetium-99m scintigraphy. The imaging appearance of the pediatric spleen depends on the patient's age and the modality used; however, familiarity with the spectrum of radiologic patterns of splenic involvement will facilitate correct diagnosis and prompt treatment.

Intense contrast enhancement of the adrenal glands: another abdominal CT finding associated with hypoperfusion complex in children

OBJECTIVE

A constellation of CT findings has been associated with posttraumatic shock in children. Findings include fluid-filled, dilated bowel; intense enhancement of bowel wall, mesentery, pancreas, kidneys, aorta, and inferior vena cava; and small caliber of aorta and inferior vena cava. The objective of this study is to describe an additional CT finding in the hypoperfusion complex: symmetric, intense contrast enhancement of the adrenal glands.

CONCLUSION

Intense enhancement (as great as that of adjacent vascular structures) of normal-shaped adrenal glands occurs in association with hemodynamic instability in children. The presence of intense adrenal enhancement may provide additional evidence of hemodynamic instability and help differentiate it from direct bowel injury.

Hyperpolarized 3He-enhanced MR imaging of lung transplant recipients: preliminary results

OBJECTIVE

Bronchiolitis obliterans syndrome is the major cause of long-term graft failure in lung transplant recipients and may be partially reversible if diagnosed early and treated. Diagnosis is difficult because findings of transbronchial biopsy are often negative in patients with early disease. We are investigating a novel MR ventilation agent, hyperpolarized 3He, for evaluating ventilatory abnormalities in lung transplant recipients with suspected bronchiolitis obliterans syndrome.

CONCLUSION

In this preliminary study, the extent of ventilatory defects revealed on 3He-enhanced MR images correlated with severity of bronchiolitis obliterans syndrome using an established clinical grading system. This new technique may hold potential for diagnosing bronchiolitis obliterans syndrome in lung transplant recipients.

Gastric retention of zinc-based pennies: radiographic appearance and hazards

PURPOSE

To determine the radiographic appearance and features of corrosion in U.S. coins exposed to gastric acid.

MATERIALS AND METHODS

Six U.S. copper-based pre-1982 pennies, 12 zinc-based post-1982 pennies, a quarter, a nickel, and a dime were exposed to postprandial concentrations of gastric acid (0.15N HCl) for 7 days, and radiographs were obtained daily. Half the zinc-based coins were scraped to disrupt their copper coating. Coins were weighed at the start and completion of the study.

RESULTS

Post-1982 zinc-based pennies developed radiolucent corrosive changes within 24 hours. Erosions on the coins became more apparent over time. Frank holes were present on day 2. The weights of these coins decreased 5%-8% during the study. Pre-1982 copper pennies and "silver-colored" coins showed no change on radiographs over 7 days.

CONCLUSION

Unexpected radiolucent corrosions may develop in post-1982 zinc alloy pennies when retained in the stomach. Coins have long been considered innocuous foreign bodies in the gastrointestinal tracts of children. However, because of the potential for ulceration and zinc-related morbidity, closer clinical and radiographic observation is warranted. Coins with scalloped edges or holes should be endoscopically removed, as they have likely been retained longer than 1 or 2 days.

Purulent pericarditis presenting as acute abdomen in children: abdominal imaging findings

Purulent pericarditis is rapidly fatal if untreated [1,2]. With increased development of bacterial resistance to antibiotics, severe bacterial infections in children are becoming more frequent [3,4]. We report two children with purulent pericarditis who presented in a 1-month period for evaluation of acute abdominal distention and signs of sepsis. In both, one evaluated with computed tomography (CT) and one with ultrasound, abdominal findings included periportal edema, gallbladder wall thickening, and ascites secondary to right heart failure from cardiac tamponade. Radiologists should be aware that children with purulent pericarditis may have a normal heart size on radiographs, present with acute abdominal symptoms, and demonstrate findings of right sided heart failure on abdominal imaging.

Imaging of pediatric mesenteric abnormalities

The relative paucity of mesenteric fat seen in the pediatric population can make detection and localization of processes in the mesentery difficult. This pictorial essay reviews pediatric mesenteric disorders and presents criteria that help localize processes to the mesentery. Disorders are categorized by specific patterns of involvement, which can readily be identified by imaging: developmental abnormalities of mesenteric rotation, diffuse mesenteric processes, focal mesenteric masses, and multifocal mesenteric masses.

Cystic fibrosis: combined hyperpolarized 3He-enhanced and conventional proton MR imaging in the lung--preliminary observations

Four patients with cystic fibrosis (CF) were examined with combined hyperpolarized helium 3-enhanced and conventional proton magnetic resonance (MR) imaging. After inhalation of the polarized 3He gas, single breath-hold, gradient-echo images (resonant frequency of 3He) were obtained to depict lung ventilation. Conventional T2-weighted fast spin-echo (hydrogen) images were also obtained to depict morphologic abnormalities. 3He images were successfully and reproducibly generated that showed both morphologic abnormalities and, often more extensive, ventilation abnormalities. 3He MR imaging may provide a method for evaluating progression of pulmonary disease in patients with CF.

Anterior chest wall: frequency of anatomic variations in children

PURPOSE

To evaluate the frequency of anterior chest wall variations in children.

MATERIALS AND METHODS

The computed tomographic (CT) images of 200 consecutive infants and children (114 boys and 86 girls; mean age, 10.5 years; age range, 3 months to 19 years) who underwent chest CT during a 20-month period were evaluated for chest wall variations. Children who had undergone chest wall surgery or were suspected of having a chest wall abnormality were excluded. The frequency of chest wall anomalies was compared with age and sex (Fisher exact test).

RESULTS

The CT scans of 65 children (33%) depicted one or more variations in the anterior chest wall: titled sternum (n = 29), prominent convexity of anterior rib or costal cartilage (n = 19), prominent asymmetric costal cartilage (n = 20), well-defined paracostal subcutaneous nodule (n = 4), mild pectus excavatum (n = 4), or mild pectus carinatum (n = 4). The frequency of these findings did not vary significantly with age (P = .96) or sex (P = .36).

CONCLUSION

Variations in the anterior chest wall are common, occurring in one-third of children, and should be considered normal. These asymptomatic variations should not be considered alarming when palpated at physical examination.