Safety of Administering Furosemide During Nuclear Diuretic Renography in Patients With Sulfonamide Allergies.

OBJECTIVE: We reviewed the safety of nuclear diuretic renography with furosemide in patients with sulfonamide allergies. The electronic health record was used to uncover any drug effects reported within 30 days of diuretic renograms performed between January 2009 and December 2015. CONCLUSION: Eighty-three of 1103 (7.5%) diuretic renograms were performed on patients with sulfonamide allergies. Two instances of minor rash occurred. No serious reactions occurred. Furosemide is associated with an extremely low risk of minor reactions in patients with sulfonamide allergies.

Reading the Writing in Radiology: 1923-2013.

The style and tone of the writing in Radiology has changed over the years since its first publication in 1923. Many of the tonal changes have occurred transiently and likely in relation to political and professional issues in play at a particular time. Others represent more consistent trends in the evolution of the professional writing style. In this report, we analyze the tone of the editorial content from 1923 to 2013 in a historical context as well as progressive changes in readability parameters involving both editorial and technical content.

Pediatric brown adipose tissue: detection, epidemiology, and differences from adults.

OBJECTIVES: To evaluate the prevalence and factors affecting the detection of active brown adipose tissue (BAT) in children and adolescents using (18)F-fluorodeoxyglucose positron emission tomography. STUDY DESIGN: A total of 385 positron emission tomography scans performed for various oncologic indications in 172 patients aged 5-21 years were reviewed. BAT activity was detected by visual inspection as present or absent in the neck, thorax, and abdomen based on its well-characterized and typical appearance and then quantified by comparing the (18)F-fluorodeoxyglucose activity in the cervical-supraclavicular depots with that measured in the liver. Clinical indices were recorded. RESULTS: The BAT detection rate was not significantly different between boys and girls (43.3% vs 45.3%). BAT activity was found most often in the cervical-supraclavicular depots. The highest percentage of patients with detectable BAT and the highest BAT/liver activity were in the 13- to 14.99-year age group in both males and females (P = .005). Body mass index percentile correlated inversely with BAT activity (P = .012). BAT activity did not correlate with outdoor temperature or clinical diagnosis. CONCLUSION: Under typical clinical imaging conditions, BAT is detected more frequently in children than in adults. BAT activity increases from childhood into adolescence, when it is detected in almost half of patients, and it correlates inversely with obesity, suggesting that BAT may play a prominent role in pediatric metabolism.

PET and PET/CT in pediatric oncology.

18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and FDG-PET/computed tomography (CT) are becoming increasingly important imaging tools in the noninvasive evaluation and monitoring of children with known or suspected malignant diseases. In this review, we discuss the preparation of children undergoing PET studies and review radiation dosimetry and its implications for family and caregivers. We review the normal distribution of 18F-fluorodeoxyglucose (FDG) in children, common variations of the normal distribution, and various artifacts that may arise. We show that most tumors in children accumulate and retain FDG, allowing high-quality images of their distribution and pathophysiology. We explore the use of FDG-PET in the study of children with the more common malignancies, such as brain neoplasms and lymphomas, and the less-common tumors, including neuroblastomas, bone and soft-tissue sarcomas, Wilms' tumors, and hepatoblastomas. For comparison, other PET tracers are included because they have been applied in pediatric oncology. Multiple multicenter trials are underway that use FDG-PET in the management of children with neoplastic disease; these studies should give us greater insight into the impact FDG-PET can make in their care. PET is emerging as an important diagnostic imaging tool in the evaluation of pediatric cancers. The recent advent of dual-modality PET-computed tomography (PET/CT) imaging systems has added unprecedented diagnostic capability by revealing the precise anatomical localization of metabolic information and metabolic characterization of normal and abnormal structures. The use of CT transmission scanning for attenuation correction has shortened the total acquisition time, which is an especially desirable attribute in pediatric imaging. Moreover, expansion of the regional distribution of the most common PET radiotracer, FDG, and the introduction of mobile PET units have greatly increased access to this powerful diagnostic imaging technology. Here, we review the clinical applications of PET and PET/CT in pediatric oncology. General considerations in patient preparation and radiation dosimetry will be discussed.

MRI for detection of abscess in acute osteomyelitis of the pelvis in children.

OBJECTIVE: We analyzed our experience with MRI of pelvic acute hematogenous osteomyelitis (AHO) to address the following questions: What does MRI reveal about bone involvement? How often are fluid collections indicative of abscess shown? Are clinical parameters predictive of the cases in which MRI would be more beneficial? MATERIALS AND METHODS: We retrospectively reviewed the imaging studies and medical records from the past 5 years of 38 children ranging in age from 25 to 211 months who were diagnosed with pelvic osteomyelitis using MRI. Statistical analysis of demographic and clinical variables was compared between patients with an abscess (n = 21) and those without (n = 17) who were identified on MRI. RESULTS: Osteomyelitis involved metaphyseal equivalent sites in every case (n = 38), with single bone involvement in 24 (63%) and contiguous bone involvement in the remaining 14 (37%). Fluid collections indicative of an abscess were seen in 21 cases (55%), and abscess drainage was performed in 10 (26%). Univariate analysis of demographic and clinical variables between patients with and without an abscess indicated no significant differences for any variable except erythrocyte sedimentation rate (ESR) (74 +/- 19 vs 56 +/- 24 mm/h; p< 0.05, Student's t test). CONCLUSION: Childhood pelvic AHO is relatively uncommon and produces variable signs and symptoms that are often attributed to another process. The results of our study show the ability of MRI to provide additional information that affected patient management in cases of pelvic abscess. We therefore advocate the use of MRI as the imaging technique of choice for any child suspected of having pelvic AHO.

MR imaging of congenital/developmental and acquired disorders of the pediatric hip and pelvis.

This article reviews the MR imaging findings of some of the more common congenital and acquired disorders of the pediatric hip and pelvis,with the intent of increasing the awareness of radiologists and facilitating early and accurate diagnosis and treatment. The importance of MR imaging in the pediatric population is underscored by its ability to evaluate these disorders well and without the use of ionizing radiation.

Acute hematogenous osteomyelitis of children: assessment of skeletal scintigraphy-based diagnosis in the era of MRI.

UNLABELLED: The emergence of MRI has challenged the long-standing primacy of skeletal scintigraphy in pediatric cases of suspected acute hematogenous osteomyelitis (AHO) with nondiagnostic radiographs. This study evaluated a strategy in which skeletal scintigraphy is the primary and MRI a supplemental test. METHODS: We reviewed the records of 213 children (age range, 8 mo-18 y; mean age, 67 mo) with musculoskeletal symptoms and nondiagnostic radiographs who were referred for skeletal scintigraphy because of the possibility of AHO. MRI was performed when diagnostic uncertainty persisted after skeletal scintigraphy or when abscess was suspected. RESULTS: Diagnosis was made using skeletal scintigraphy without referral for MRI in 179 (84%) of the children, including 79 (92%) of 86 with a final diagnosis of AHO. In no instance was the diagnosis of AHO indicated only by MRI. Treatment and diagnosis were accomplished without referral for MRI in 146 (69%) of all cases and 46 (53%) of the AHO cases. Abscesses that required drainage were found in 3 (6%) of 48 cases of major-long-bone AHO. Each of these 3 had exhibited a slow therapeutic response before MRI. Drainable abscesses were found in 5 (20%) of 25 cases affecting the pelvis, which was the other preponderant location of AHO. These were found with pelvic foci both when MRI was performed at diagnosis and when MRI was performed during treatment. CONCLUSION: An imaging strategy in which skeletal scintigraphy is the first test used when AHO is suspected but radiographs are negative remains highly effective. This approach can be most strongly advocated when symptoms are poorly localized or are localized to major long bones. MRI should be performed after skeletal scintigraphy shows major-long-bone AHO if treatment response is slow. Skeletal scintigraphy is also an appropriate first test for suspected radiographically occult pelvic AHO. Because of the association of abscesses with pelvic AHO, however, the use of MRI should be strongly considered after pelvic AHO is detected, and MRI might be substituted diagnostically for skeletal scintigraphy when symptoms are well localized to the pelvis.

Skeletal scintigraphy of young patients with low-back pain and a lumbosacral transitional vertebra.

UNLABELLED: Lumbosacral transitional vertebrae can alter the biomechanics of weight transfer at the affected spinal segment. Low-back pain may result. This study assessed what skeletal scintigraphy reveals about stress associated with a lumbosacral transitional vertebra in young patients with low-back pain. METHODS: The study population included 48 patients (30 male, 18 female; age range, 6-19 y; mean age, 15.7 y) with low-back pain and a lumbosacral transitional vertebra. Skeletal scintigraphy was correlated with plain radiographs in all, CT in 12, and MRI in 11. RESULTS: High uptake was shown at the articulation between the transverse process of a lumbosacral transitional vertebra and the sacrum in 39 (81%) of the patients. In 23 (59%) of the 39 patients with high uptake, this finding was shown only by SPECT. In 13 (81%) of the 16 for which the high uptake was shown by planar imaging, the anterior projection was more valuable than the posterior projection. In 9 (23%) of the 39 patients with high uptake at the transverse-sacral articulation, the lumbosacral transitional vertebra had not been noted in a radiographic report before skeletal scintigraphy but was identified through reevaluation or repetition of radiographs after skeletal scintigraphy. Radiographs showed sclerosis along the transverse-sacral articulation in only 8 (21%) of the 39 patients with high uptake. Findings indicating stress or motion at the joint were shown by CT in 6 (55%) of 11 and by MRI in 5 (63%) of 8 patients with high uptake at the transverse-sacral articulation who underwent these examinations. CONCLUSION: Skeletal scintigraphy often indicates stress at the transverse-sacral articulation of young patients with low-back pain and a lumbosacral transitional vertebra. Showing evidence of stress is best accomplished using SPECT. Changes are usually not radiographically evident, but there is a trend for MRI and CT to show findings that imply stress or motion at the articulation. The unique ability of skeletal scintigraphy to provide this physiologic information supports its use in these patients.

Rib stress fractures.

The ribs are an uncommon site of stress fracture. Typical locations are the first rib anterolaterally, the fourth through ninth ribs laterally and posterolaterally, and the posteromedial upper ribs. Muscular forces are predominantly responsible for these fractures. This article reviews the mechanisms of injury in various activities and illustrates the scintigraphic appearance of rib stress fractures.

Thymic uptake of radiopharmaceuticals.

The thymus, as the site of T-cell differentiation, plays a critical role in the development of the immune system. The gland increases in weight until puberty and then is slowly replaced by fat. Various radiopharmaceuticals can localize to the thymus before it involutes. This pictorial presentation reviews the appearance and proposed mechanisms of thymic uptake of Ga-67 citrate, F-18 fluorodeoxyglucose, radioiodine, and In-111 pentetreotide.

Skeletal scintigraphy in the multimodality assessment of young children with acute skeletal symptoms.

The authors review the scintigraphic manifestations of acute osteomyelitis, septic arthritis, transient synovitis, Legg-Calvé-Perthes disease, fractures of toddlers, and some systemic conditions that cause skeletal symptoms during childhood. They offer suggestions regarding incorporation of skeletal scintigraphy into a multimodality approach for assessing children with skeletal symptoms.

Aneurysmal bone cyst of the sacrum: value of three-phase imaging.

Aneurysmal bone cyst is an uncommon nonneoplastic lesion that occurs predominantly during the first 2 decades of life. Angiographic- and tissue-phase imaging provided more striking evidence of this unexpected lesion than skeletal-phase imaging in a 13-year-old girl with pain in the right buttock and posterior thigh.

Localization of Tc-99m MDP in the rectus abdominis muscle without associated symptoms.

Skeletal tracer localization in the rectus abdominis muscle of a 17-year-old girl whose training regimen included vigorous abdominal exercise but who had no abdominal soreness is described. The case illustrates that bone tracers may localize to skeletal muscle without associated symptoms. This is consistent with bone tracer localization in skeletal muscle reflecting subtle fiber abnormalities rather than necrosis.

Applications of nuclear medicine in pediatric oncology.

Nuclear medicine is important in the diagnosis, staging, and long-term surveillance of a number of pediatric cancers. Skeletal scintigraphy is used to evaluate primary skeletal cancers, such as osteosarcoma and Ewing sarcoma, and nonskeletal cancers such as neuroblastoma, lymphoma, medulloblastoma, rhabdomyosarcoma, and retinoblastoma. Metaiodobenzylguanidine scintigraphy is valuable in examinations of children with neuroblastoma. The therapeutic response of primary bone and brain tumors can be assessed using Tl-201 and Tc-99m MIBI scintigraphy. Imaging strategies for staging and monitoring the therapeutic response of Hodgkin's lymphoma include Ga-67 citrate scintigraphy. Pediatric oncologic applications of positron emission tomography are being investigated extensively.

Young athletes with low back pain: skeletal scintigraphy of conditions other than pars interarticularis stress.

PURPOSE: Skeletal scintigraphy is an important method for showing evidence of stress injuries affecting the partes interarticulares of young athletes with low back pain. Other etiologies of low back pain may also cause uptake abnormalities in these patients. How often do the results of skeletal scintigraphy support diagnoses other than stress injuries to the partes interarticulares and what are these diagnoses? MATERIALS AND METHODS: We retrospectively reviewed the records of 209 young patients (149 females, 60 males; age range: 8-21 years, mean: 15.7 years) with low back pain and no previously treated vertebral condition who were consecutively referred from a sports medicine clinic to skeletal scintigraphy. RESULTS: Sites of high uptake supportive of diagnoses other than pars interarticularis stress were shown in 36 (17%) of the 209 patients. Other diagnoses supported by skeletal scintigraphy included stress at the articulation between a transitional vertebra and the sacrum, injuries to the vertebral body ring apophysis, sacral fracture, spinous process injury, and sacroiliac joint stress. CONCLUSION: Skeletal scintigraphy shows uptake abnormalities supportive of diagnoses other than pars interarticularis stress in a significant number of young patients with low back pain. The uptake abnormalities shown are usually stress-related in this select population.

Ectopic ureteroceles in infants with prenatal hydronephrosis: use of renal cortical scintigraphy.

PURPOSE: This study assesses the contribution of renal cortical scintigraphy in the diagnostic evaluation of infants with ectopic ureteroceles. METHODS: The records of 20 infants (age range, 3 weeks to 4 months) who were referred for renal cortical scintigraphy after an ectopic ureterocele associated with a duplex kidney was found during follow-up of prenatal hydronephrosis were reviewed retrospectively. All infants underwent voiding cystourethrography, ultrasonography, and Tc-99m DMSA scintigraphy. RESULTS: All upper moieties showed absent or depressed Tc-99m DMSA uptake. Upper moiety functional impairment was associated with structural abnormalities shown by ultrasonography. The degree of functional impairment was reflective of ultrasonographically defined cortical thickness relative to pelvic diameter, but this relation varied. Eight of 20 (40%) lower moieties had diffusely depressed relative Tc-99m DMSA uptake. Focal defects were also present in three of these eight (38%) lower moieties. Lower moiety functional impairment was associated with higher degrees of pelvic dilatation and with vesicoureteral reflux. Ultrasonography revealed diffuse parenchymal thinning in four of the eight (50%) lower moieties with depressed uptake. Ultrasonography did not define focal parenchymal loss in any lower moiety. CONCLUSIONS: The degree to which function is impaired in the upper moieties of duplex kidneys with ureters terminating in ectopic ureteroceles is not highly predictable by ultrasonography. Lower moiety functional impairment and cortical defects are frequently present in these kidneys and often occur without ultrasonographic evidence of parenchymal damage. Use of renal cortical scintigraphy in the diagnostic evaluation of infants with ectopic ureteroceles is supported.