Air intussusception reduction: "the winds of change".

AIR is an excellent example of the application of the scientific process to the treatment of pediatric disease. For more than 40 years, pediatric radiologists in North America were comfortable with hydrostatic enemas for the diagnosis and treatment of intussusception. Initial clinical trials in the 1980s suggested the efficacy of AIR. Subsequent clinical studies demonstrated that fluoroscopy time and radiation are less, accurate pressure measurements are possible, and reduction rates are higher with AIR than with hydrostatic techniques. Questions regarding safety and types of perforation were answered in the laboratory with an animal model. Moreover, this experimental work clarified issues regarding maximum pressures and the importance of the Valsalva maneuver during AIR. Experimental data has been transferred to the radiological treatment of childhood intussusception. The "winds of change", generated by clinical and basic research, have now swept across North America. More and more radiologists are performing AIR. Many of the pediatric radiologists who still doubt the efficacy of AIR have had no experience with the technique. Air insufflation is safe and effective for the diagnosis and treatment of intussusception in infants and children. It is replacing the hydrostatic enema in an ever-increasing number of institutions. AIR is quicker, safer, and more effective than hydrostatic enemas. If you are using AIR, I hope this overview will further improve the radiological care of your pediatric patients. If you are not using AIR, I hope that these personal observations will stimulate your interest. "Try it; you'll like it!"

Clinical proton MR spectroscopy of neurodegenerative disease in childhood.

PURPOSE: To determine the contribution of MR spectroscopy in the assessment of childhood neurodegenerative disease. METHODS: Fifty-one subjects (7 weeks to 17 years of age), 22 with either hereditary (n = 16) or acquired (n = 6) neurodegenerative disorders and 29 age-matched control subjects, were studied with combined proton MR spectroscopy and MR imaging. Single-voxel (2.0-8.0 cc) MR spectra were acquired at 1.5 T, with either short-echo-stimulated echoes and/or long-echo spin echoes. RESULTS: MR spectra exhibited signals from n-acetyl-, creatine-, and choline-containing compounds, neurotransmitters (glutamate), intracellular mediators (inositols), and glycolytic products (lactate). Abnormal MR spectra in neurodegenerative disorders reflected: demyelination, neuronal loss, and gliosis (increased mobile lipid presence and reduction of n-acetylaspartate to choline); metabolic acidosis (lactate accumulation); and neurotransmitter neurotoxicity (increased glutamate, glutamine, and inositols). CONCLUSION: Proton MR spectroscopy may complement MR imaging in diagnostic assessment and therapeutic monitoring of neurodegenerative disorders.

Childhood adrenoleukodystrophy: assessment with proton MR spectroscopy.

PURPOSE: Image-guided, single-voxel, localized proton magnetic resonance (MR) spectroscopy was performed to assess white matter in childhood adrenoleukodystrophy (ALD). MATERIALS AND METHODS: Eleven X-linked ALD subjects, seven with neurologic symptoms or white matter lesions at MR imaging and four asymptomatic patients, were compared with nine aged-matched, healthy volunteers. RESULTS: Compared with those from normal white matter, MR spectra from white matter lesions (n = 6) showed 65% reduction in the ratio of N-acetyl aspartate (NAA) to total creatine (tCr) (P < .01); 55% increase in the ratio of choline-containing compounds (Cho) to tCr (P < .02); substantial levels of tCr; 94% increase in the ratio of glutamate, glutamine, or inositol to tCr (P < .02); and lactate accumulation in four patients. Patients without brain lesions (n = 4) exhibited a 51% increase in Cho-to-tCr ratio (P < .01) and 11% nonsignificant increase in NAA-to-tCr ratio. CONCLUSION: Proton MR spectroscopy may prove a valuable technique for noninvasive diagnostic and prognostic assessment of ALD.

Localized proton MR spectroscopy of the brain in children.

Small-voxel (3.0-8.0 cm3), magnetic resonance (MR) imaging-guided proton MR spectroscopy was performed in 54 patients (aged 6 days to 19 years) with intracranial masses (n = 16), neurodegenerative disorders (n = 34), and other neurologic diseases (n = 4) and in 23 age-matched control subjects without brain disease. A combined short TE (18 msec) stimulated-echo acquisition mode (STEAM) and long TE (135 and/or 270 msec) spin-echo point-resolved spatially localized spectroscopy (PRESS) protocol, using designed radio-frequency pulses, was performed at 1.5 T. STEAM spectra revealed short T2 and/or strongly coupled metabolites; prominent resonances were obtained from N-acetyl aspartate (NAA), choline-containing compounds (Cho), and total creatine (tCr). Lactate was well resolved with the long TE PRESS sequence. Intracranial tumors were readily differentiated from cerebrospinal fluid (CSF) collections. All tumors showed low NAA, high Cho, and reduced tCr levels. Neurodegenerative disorders showed low or absent NAA levels and enhanced mobile lipid, glutamate and glutamine, and inositol levels, consistent with neuronal loss, gliosis, demyelination, and amino acid neurotoxicity. Preliminary experience indicates that proton MR spectroscopy can contribute in the evaluation of central nervous system abnormalities of infants and children.

John Caffey Award. Colonic perforation by air and liquid enemas: comparison study in young pigs.

OBJECTIVE: Hydrostatic enema reduction of intussusception in children has been replaced by pneumatic reduction in a number of institutions. Colonic perforation occurs in as many as 2.8% of enema reductions, and questions persist about the relative safety of enemas performed with air vs fluid. The objectives of this study were to investigate and compare the pathologic patterns of in vivo colonic perforation and fecal spillage in young pigs given air and hydrostatic enemas, with and without the Valsalva maneuver. MATERIALS AND METHODS: Colonic perforations were induced in 135 juvenile pigs. The pigs were divided into five groups, and enemas with air, barium, and water-soluble contrast material were given with and without the Valsalva maneuver to induce the perforations. During the enemas, the Valsalva maneuver was observed when the animals strained. In each animal, the enema was continued and pressure increased until a perforation was detected with fluoroscopy. Radiographic, gross, and histologic examinations of each animal were performed after perforations occurred. Differences in fecal spillage were noted, and the morphologic variations of the perforations and the surrounding tissue were determined. RESULTS: Perforations with hydrostatic (barium, water-soluble) enemas occurred at approximately 120 mm Hg of pressure (average bag height, 57 in. [143 cm]). No significant variations were found between the type of material used for contrast or the use of the Valsalva maneuver. With air enemas, perforations occurred at a mean pressure of 108 mm Hg without the Valsalva maneuver and at 145 mm Hg with the Valsalva maneuver. Perforations during air enemas did not occur during the Valsalva maneuver (pressures as high as 270 mm Hg), but rather between Valsalva maneuvers. Hydrostatic enemas produced full-thickness tears that were larger than those induced by air enemas in all cases. Air enemas with and without the Valsalva maneuver produced partial-thickness tears in 45% and 10%, respectively, of the pigs. Fecal spillage was diffuse in all hydrostatic perforations. In air enemas, spillage was focal in 55% and 90%, respectively, and absent in 45% and 10%, respectively, of perforations produced with and without the Valsalva maneuver. CONCLUSION: Our results suggest that air enemas are safer than liquid enemas. Perforations that occurred during air enemas were smaller and associated with less fecal spillage and peritoneal contamination. The Valsalva maneuver appears to prevent colonic perforation during air enemas.

Cerebral perfusion in children: detection with dynamic contrast-enhanced T2*-weighted MR images.

Cerebral perfusion dynamics were assessed with dynamic contrast material-enhanced T2*-weighted magnetic resonance (MR) imaging in 33 subjects aged 3-20 years. Group A (n = 20) had sickle cell anemia without clinical evidence of cerebrovascular disease. Group B (n = 13) consisted of 12 patients with cerebrovascular disease and homozygous sickle cell anemia and one patient without that anemia. All subjects underwent conventional MR imaging and a dynamic study in which a spoiled gradient-echo pulse sequence was used to generate images (acquisition time, 2.5 seconds) during injection of a compact bolus of gadopentetate dimeglumine (0.1 mmol/kg). For qualitative analysis, the dynamic images were displayed in cine mode. Group A demonstrated symmetric sequential region patterns of loss of signal intensity within 10 seconds of injection. Group B exhibited signal loss asymmetries that corresponded to cerebrovascular lesions on conventional MR images. Quantitative analysis enabled estimation of hemodynamic parameters, including relative cerebral blood volume, relative cerebral blood flow, and mean transit time. This method of assessment of cerebral perfusion dynamics complements conventional MR imaging.

Multicystic dysplastic kidney in children: US follow-up.

Eighty-one cases of multicystic dysplastic kidney (MCDK) in children were diagnosed over the past 11 years at the authors' institution: 25 children had their kidneys surgically removed, eight with bilateral total involvement died, and 48 underwent serial follow-up ultrasonography (US) of their kidneys. Follow-up included 193 serial ultrasound (US) studies (mean, four per patient) for a total of 1,468 months (mean, 30.5 months). In the 48 patients followed up, 32 (67%) kidneys showed a decrease in size, nine (19%) showed no change, and five (10%) increased in size, and in two (4%), a change in size could not be determined. In seven of the 48 (15%) children, the MCDKs decreased in size, and, at follow-up US, no renal tissue could be found. In those patients in whom MCDKs decreased in size. Serial US characteristics changed from predominantly an enlarged cystic structure to a small dysplastic or absent kidney. Two of the five kidneys that increased in size were surgically removed, and MCDK was pathologically confirmed. A nonsurgical approach to the treatment of patients with MCDK is supported by this study.

Evaluation of the craniocervical junction in Down syndrome: correlation of measurements obtained with radiography and MR imaging.

Measurement of the atlas-dens interval is the radiographic standard for identification of patients with Down syndrome at high risk for neurologic injury from spinal cord compression. In 17 pediatric patients with Down syndrome, measurements of the atlas-dens interval, distance between the clivus and posterior odontoid process, and width of the neural canal obtained with plain radiographs were compared to predict the width of the subarachnoid space on magnetic resonance (MR) images. In all patients, cervical radiography and craniocervical MR imaging were prospectively performed during lateral flexion and extension. The width of the subarachnoid space was measured with MR imaging. When the 95% confidence interval for correlation coefficients of regression was used, subarachnoid space width on MR images correlated with neural canal width on radiographs better than with either atlas-dens interval or clivus-posterior odontoid process distance (P = .05). Measurement of neural canal width is a better predictor of potential spinal cord compression than the atlas-dens interval or clivus-posterior odontoid process distance and should be emphasized in screening examinations performed with plain radiography.

Ultrasonography of acute epitrochlear lymphadenitis.

While the clinical symptomatology and radiographic findings of acute suppurative infection of the epitrochlear lymph nodes of the arm have been previously described, ultrasonographic findings have not been reported. This case report demonstrates that sonographic identification of enlarged epitrochlear lymph nodes immediately confirms the diagnosis. We summarize the clinical, radiological, and sonographic findings of acute suppurative infection of the epitrochlear lymph nodes.

Imaging of nephroblastomatosis: an overview.

Nephroblastomatosis is an abnormality of nephrogenesis characterized by incomplete maturation of primitive nephrogenic cells. The resultant individual lesions have variable histologic findings and distribution in the kidney. There is wide acceptance of nephroblastomatosis as a precursor lesion to Wilms tumor. Consequently, the role of imaging in assessing patients for neoplastic transformation of nephroblastomatosis should be emphasized. Computed tomography (CT) has been shown to be superior to ultrasound (US) in this regard. Nonetheless, the low cost and lack of radiation of US make it attractive for serial screening studies. Although magnetic resonance imaging shows promise in assessment of the kidney for nephrogenic rests, experience is limited in its use in evaluating patients for nephroblastomatosis. The authors present protocols for assessing patients identified as being at either high or low risk for the development of Wilms tumor due to nephroblastomatosis. These protocols take into account the advantages of CT and US. Scanning intervals are determined from epidemiologic data on the occurrence of Wilms tumor; the most intense screening occurs during the younger ages of life, when the likelihood of Wilms tumor development is highest.

Fluoroscopic catheter removal of blunt esophageal foreign bodies. A pediatric radiologist's perspective.

Fluoroscopic catheter removal of blunt esophageal foreign bodies is a safe, efficacious, time-effective, and cost-effective technique.

Air enema for diagnosis and reduction of intussusception: clinical experience and pressure correlates.

Air enema was used for exclusion, diagnosis, initial movement, and complete reduction of intussusception in 186 pediatric patients. Average pressure needed for initial movement of intussusception was 56.5 mm Hg; average maximum pressure of 97.8 mm Hg was required for complete reduction. Average fluoroscopy time required for intussusception reduction was 94.8 seconds; an average of 41.8 seconds was required to exclude intussusception. Intussusception was diagnosed in 75 patients, and reduction was accomplished in 65 (87%). Of 100 consecutive patients that underwent hydrostatic reduction of intussusception at the authors' institution, reduction was successful in 55. Compared with hydrostatic enema, air enema involves shorter fluoroscopy time and lower radiation dose to the patient. Air enema is safe and effective for diagnosis and treatment of intussusception in infants and children and has replaced hydrostatic enema for such procedures at the authors' institution.

Esophageal inflammation and stricture: complication of chronic granulomatous disease of childhood.

Esophagitis in children with immunodeficiency is most commonly due to opportunistic infection. The authors describe three patients with chronic granulomatous disease (CGD) of childhood who developed esophageal strictures that were believed to be complications of the primary disease. At radiologic examination, all three patients initially had a focal narrowing of the upper thoracic esophagus. Endoscopy showed no signs of opportunistic infection or Barrett esophagus. Biopsy of the strictures in two patients revealed findings consistent with CGD. In two of the three patients, inflammation extended to involve the middle and distal esophagus. Long-term response to balloon dilation was poor in the first two patients. The third patient was lost to follow-up after a partial clinical and radiographic response to dilation.

Traumatic atlanto-occipital disruption in children.

Ten cases of traumatic atlanto-occipital disruption in pediatric patients are reported. All injuries resulted from motor vehicle accidents, the majority of which were pedestrian/automobile. Three patients survived their injury for a period greater than one year. The importance of recognizing atlanto-occipital disruption is stressed because of its relative frequency in severely traumatized pediatric patients, particularly pedestrian/vehicle incidents, and because of the potential for survival. Diagnosis, in most instances, is based on the lateral cervical spine radiograph. The most applicable diagnostic features in children, as demonstrated on the lateral cervical spine radiograph, are reviewed.