Rate of head ultrasound abnormalities at one month in very premature and extremely premature infants with normal initial screening ultrasound.

BACKGROUND: Premature infants are at risk for multiple types of intracranial injury with potentially significant long-term neurological impact. The number of screening head ultrasounds needed to detect such injuries remains controversial. OBJECTIVE: To determine the rate of abnormal findings on routine follow-up head ultrasound (US) performed in infants born at ≤ 32 weeks' gestational age (GA) after initial normal screening US. MATERIALS AND METHODS: A retrospective study was performed on infants born at ≤ 32 weeks' GA with a head US at 3-5 weeks following a normal US at 3-10 days at a tertiary care pediatric hospital from 2014 to 2020. Exclusion criteria included significant congenital anomalies, such as congenital cardiac defects necessitating surgery, congenital diaphragmatic hernia or spinal dysraphism, and clinical indications for US other than routine screening, such as sepsis, other risk factors for intracranial injury besides prematurity, or clinical neurological abnormalities. Ultrasounds were classified as normal or abnormal based on original radiology reports. Images from initial examinations with abnormal follow-up were reviewed. RESULTS: Thirty-three (14.2%) of 233 infants had 34 total abnormal findings on follow-up head US after normal initial US. Twenty-seven infants had grade 1 germinal matrix hemorrhage, and four had grade 2 intraventricular hemorrhage. Two had periventricular echogenicity and one had a focus of cerebellar echogenicity that resolved and was determined to be artifactual. CONCLUSION: When initial screening head ultrasounds in premature infants are normal, follow-up screening ultrasounds are typically also normal. Abnormal findings are usually limited to grade 1 germinal matrix hemorrhage.

Improved diagnostic confidence and accuracy of pediatric elbow fractures with digital tomosynthesis.

BACKGROUND: Pediatric elbow fractures are common but remain challenging to accurately diagnose. Digital tomosynthesis is a technique that has shown promise in difficult adult fracture patterns but has not been formally studied in the pediatric population. OBJECTIVE: To assess the added value of digital tomosynthesis on the detection and diagnostic confidence of pediatric elbow fractures. MATERIALS AND METHODS: A retrospective study was performed between January 2016 and December 2017 in pediatric patients (≤18 years) to assess the ability of conventional elbow radiographs and digital tomosynthesis to detect elbow fractures. One hundred twenty-one pediatric patients with concern for pediatric elbow trauma (64 males, 57 females; mean age: 8.1 years, range: 1 year to 17 years) were imaged with both conventional elbow radiographs and digital tomosynthesis. Two blinded pediatric radiologists identified fractures and indicated their diagnostic confidence. Observer agreement was assessed with Cohen's Kappa coefficient and a nonparametric Wilcoxon rank sum test was used to compare the degree of diagnostic confidence between standard radiographs alone and standard radiographs with digital tomosynthesis. McNemar's test was used to assess the difference in the rate of fracture detection between the two methods and sensitivity, specificity, precision, accuracy and diagnostic odds ratios were calculated. RESULTS: Compared with standard radiographs alone, standard radiographs with digital tomosynthesis improved inter-rater agreement, sensitivity, specificity, accuracy, precision and the diagnostic odds ratio for fracture detection and increased diagnostic confidence (Rater 1: P=0.01, Rater 2: P=0.003). CONCLUSION: The addition of digital tomosynthesis with conventional elbow radiographs improves diagnostic confidence and performance for the detection of pediatric elbow fractures.

Congenital Oral Masses: An Anatomic Approach to Diagnosis.

Although congenital oral masses are rare, they are readily detectable during fetal US screening. Most congenital oral masses are benign, but some may cause mechanical airway obstruction, resulting in poor outcomes at delivery. The radiologist's ability to describe these abnormalities and their physiologic sequelae accurately can have a substantial effect on perinatal treatment. Furthermore, despite being rare, congenital oral lesions encountered at screening and at follow up fetal MRI provide the opportunity to make a specific diagnosis by following a simple anatomic approach. This article describes an anatomic algorithm as the framework for accurate diagnosis of congenital oral lesions. The imaging appearance of the most common congenital oral cavity neoplasms is outlined, including vascular anomalies, epulides, choristomas, congenital lingual thyroid anomalies, lingual hamartomas, and epignathi, and other conditions that mimic these at US. Also reviewed are perinatal management of masses that affect the fetal airway and the imaging features key to optimizing delivery outcomes. Online supplemental material is available for this article. ©RSNA, 2019.

Value of dedicated small-field-of-view sacroiliac versus large-field-of-view pelvic magnetic resonance imaging for evaluating pediatric sacroiliitis.

BACKGROUND: Optimized MRI parameters can be leveraged to improve signal intensity, accelerate imaging acquisition and increase resolution. Higher-resolution imaging with a small field of view (FOV) has been proposed as standard practice for investigating sacroiliac (SI) joints, but the improvement in disease detection and characterization over pelvic imaging with large FOV has not been established. OBJECTIVE: The purpose of this study was to compare dedicated MR images of the SI joints with survey imaging (large-FOV pelvic MRI) for detecting sacroiliitis. MATERIALS AND METHODS: Fifty-eight pediatric patients suspected of having sacroiliitis underwent dedicated sacroiliac joint and survey pelvic imaging at the same imaging session. We independently evaluated the small- and large-FOV image data sets for presence or absence of sacroiliitis, e.g., bone marrow edema, erosions and synovitis. We used nonparametric statistical tests to compare lesion scores for severity of inflammation. We created test characteristics for the survey pelvic images (low-resolution images of the sacroiliac joints) using dedicated sacroiliac images (small-FOV, high-resolution images) as the gold standard. RESULTS: Dedicated sacroiliac small-FOV MRI detected more sacroiliitis compared to survey pelvic imaging with large FOV (χ2=6.125, P=0.013). Readers detected significantly more features of inflammation on small- compared to large-FOV images, e.g., erosions (P=0.039), synovitis (P=0.009), sclerosis (P=0.017) and osteitis (P=0.001). Test characteristics for pelvic large-FOV imaging were sensitivity=0.76, specificity=1.00, positive predictive value = 1.00 and negative predictive value = 0.75. CONCLUSION: This study provides test characteristics for survey pelvic MRI with lower-resolution large-field-of-view images as a screening tool for detecting sacroiliitis. Pelvic screening studies with large FOV have lower sensitivity, and dedicated sacroiliac MRI with small FOV is superior in detecting sacroiliitis when compared to pelvic screening MRI.

Bias in Radiology: The How and Why of Misses and Misinterpretations.

Medical errors are a leading cause of morbidity and mortality in the medical field and are substantial contributors to medical costs. Radiologists play an integral role in the diagnosis and care of patients and, given that those in this field interpret millions of examinations annually, may therefore contribute to diagnostic errors. Errors can be categorized as a "miss" when a primary or critical finding is not observed or as a "misinterpretation" when errors in interpretation lead to an incorrect diagnosis. In this article, the authors describe the cognitive causes of such errors in diagnostic medicine, specifically in radiology. Recognizing the cognitive processes that radiologists use while interpreting images should improve one's awareness of the inherent biases that can impact decision making. The authors review the common biases that impact clinical decisions, as well as strategies to counteract or minimize the potential for misdiagnosis. System-level processes that can be implemented to minimize cognitive errors are reviewed, as well as ways to implement personal changes to minimize cognitive errors in daily practice. ©RSNA, 2017.

Pilot Study of Renal Diffusion Tensor Imaging as a Correlate to Histopathology in Pediatric Renal Allografts.

OBJECTIVE: Fractional anisotropy (FA) is a measure of molecular motion obtained from diffusion tensor imaging (DTI). The objective of this study was to assess the use of FA as a noninvasive correlate of renal allograft histopathology. SUBJECTS AND METHODS: Sixteen pediatric renal allograft recipients were imaged using DTI in a prospective study, between October 2014 and January 2016, before a same-day renal allograft biopsy. The Kendall tau correlation coefficient was used to assess the relationship between cortical and medullary FA values and several clinically important Banff renal allograft histopathology scores. The Mann-Whitney U test was also used to compare cortical and medullary FA values in the region of biopsy in patients whose biopsy results did and in those whose biopsy results did not change clinical management. RESULTS: Medullary FA values had direct inverse correlation with several histopathology scores: tubulitis (designated "t" score in Banff pathologic classification, p < 0.04), interstitial inflammation (i score, p < 0.005), tubular atrophy (ct score, p < 0.002), and interstitial fibrosis (ci score, p < 0.007). Cortical FA values inversely correlated with peritubular capillaritis (ptc score, p < 0.02). Neither medullary nor cortical FA values correlated with glomerulitis (g score). At a b value of 800 s/mm2, medullary FA values of pediatric renal allograft recipients whose renal biopsies prompted a change in clinical management (mean ± SD at a b value of 800 s/mm2 = 0.262 ± 0.07; n = 9) were statistically different compared with the group whose biopsy results did not change clinical management (mean ± SD at a b value of 800 s/mm2 = 0.333 ± 0.06; n = 7) (p < 0.006). CONCLUSION: FA is a noninvasive correlate of several important renal allograft histopathology scores and a potential noninvasive method of assessing renal allograft health in pediatric allograft recipients.

Pediatric renal transplant biopsy with ultrasound guidance: the 'core' essentials.

This review provides a comprehensive and practical approach to pediatric percutaneous renal transplant biopsies, highlighting techniques and strategies to optimize adequate sample yield and ensure patient safety. In children with end-stage renal disease, transplantation is the preferred choice of therapy, providing for overall lower long-term morbidity and mortality compared with dialysis. In the ongoing management of renal transplant patients, core tissue sampling via a percutaneous renal biopsy remains the gold standard when transplant dysfunction is suspected. Indications for renal transplant biopsy and techniques/tools for adequate sample yield are discussed. Strategies for common challenges such as poor visualization and renal transplant mobility are addressed. We discuss the clinical signs, techniques and imaging findings for common complications including hematomas, arteriovenous fistulas and pseudoaneurysms. Although the percutaneous renal transplant biopsy procedure is generally safe with rare complications, care must be taken to ensure major complications are promptly recognized and treated. Adequate tissue samples obtained via renal biopsy are imperative to promptly identify transplant rejection to provide valuable information for patient diagnosis, treatment and outcomes. Radiologist and nephrologist attention to proper ultrasound techniques and optimal biopsy tools are critical to ensure tissue adequacy and minimize complications.

Pediatric chest CT at chest radiograph doses: when is the ultralow-dose chest CT clinically appropriate?

PURPOSE: Computed tomography (CT) use in emergency departments represents a significant contribution to pediatric patients' exposure to ionizing radiation. Here, we evaluate whether ultralow-dose chest CT can be diagnostically adequate for other diagnoses and whether model-based iterative reconstruction (MBIR) can improve diagnostic adequacy compared to adaptive statistical iterative reconstruction (ASIR) at ultralow doses. METHODS: Twenty children underwent chest CTs: 10 standard-dose reconstructed with ASIR and 10 ultralow-dose reconstructed with ASIR and MBIR. Four radiologists assessed images for their adequacy to exclude five hypothetical diagnoses: foreign body, fracture, lung metastasis, pulmonary infection, and interstitial lung disease. Additionally, pairwise comparison for subjective image quality was used to compare ultralow-dose chest CT with ASIR and MBIR. Radiation dose and objective image noise measures were obtained. RESULTS: For exclusion of an airway foreign body, the adequacy of ultralow-dose CT was comparable to standard-dose (p = 0.6). For the remaining diagnoses, ultralow-dose CT was inferior to standard-dose (p = 0.03-<0.001). MBIR partially recovered the adequacy of ultralow-dose CT to exclude pulmonary infection (p = 0.017), but was suboptimal for the other diagnoses. Image noise was significantly lower with MBIR compared to ASIR in ultralow-dose CT (p < 0.001), although subjective preference showed only a slight advantage of MBIR (58 versus 42%). CONCLUSIONS: Ultralow-dose chest CT may be adequate for airway assessment, but suboptimal for the evaluation parenchymal lung disease. Although MBIR improves objective and subjective image quality, it does not completely restore the diagnostic adequacy of ultralow-dose CT when compared to standard-dose CT.

Image quality and dose optimisation for infant CT using a paediatric phantom.

OBJECTIVE: To optimise image quality and reduce radiation exposure for infant body CT imaging. METHODS: An image quality CT phantom was created to model the infant body habitus. Image noise, spatial resolution, low contrast detectability and tube current modulation (TCM) were measured after adjusting CT protocol parameters. Reconstruction method (FBP, hybrid iterative and model-based iterative), image quality reference parameter, helical pitch and beam collimation were systematically investigated for their influence on image quality and radiation output. RESULTS: Both spatial and low contrast resolution were significantly improved with model-based iterative reconstruction (p < 0.05). A change in the helical pitch from 0.969 to 1.375 resulted in a 23% reduction in total TCM, while a change in collimation from 20 to 40 mm resulted in a 46% TCM reduction. Image noise and radiation output were both unaffected by changes in collimation, while an increase in pitch enabled a dose length product reduction of ~6% at equivalent noise. An optimised protocol with ~30% dose reduction was identified using model-based iterative reconstruction. CONCLUSIONS: CT technology continues to evolve and require protocol redesign. This work provides an example of how an infant-specific phantom is essential for leveraging this technology to maintain image quality while reducing radiation exposure. KEY POINTS: • A size-specific phantom is critical in protocol development for infant CT. • New reconstruction technology enables ~30% dose reduction at equivalent image quality. • A consistent performance is observed for this scanner system across protocol changes. • A tradeoff exists between reducing exposure time and enabling tube current modulation.

Pairwise comparison versus Likert scale for biomedical image assessment.

OBJECTIVE: Biomedical imaging research relies heavily on the subjective and semi-quantitative reader analysis of images. Current methods are limited by interreader variability and fixed upper and lower limits. The purpose of this study was to compare the performance of two assessment methods, pairwise comparison and Likert scale, for improved analysis of biomedical images. MATERIALS AND METHODS: A set of 10 images with varying degrees of image sharpness was created by digitally blurring a normal clinical chest radiograph. Readers assessed the degree of image sharpness using two different methods: pairwise comparison and a 10-point Likert scale. Reader agreement with actual chest radiograph sharpness was calculated for each method by use of the Lin concordance correlation coefficient (CCC). RESULTS: Reader accuracy was highest for pairwise comparison (CCC, 1.0) and ranked Likert (CCC, 0.99) scores and lowest for nonranked Likert scores (CCC, 0.83). Accuracy improved slightly when readers repeated their assessments (CCC, 0.87) or had reference images available (CCC, 0.91). CONCLUSION: Pairwise comparison and ranked Likert scores yield more accurate reader assessments than nonranked Likert scores.

Computed tomography depiction of small pediatric vessels with model-based iterative reconstruction.

BACKGROUND: Computed tomography (CT) is extremely important in characterizing blood vessel anatomy and vascular lesions in children. Recent advances in CT reconstruction technology hold promise for improved image quality and also reductions in radiation dose. This report evaluates potential improvements in image quality for the depiction of small pediatric vessels with model-based iterative reconstruction (Veo™), a technique developed to improve image quality and reduce noise. OBJECTIVE: To evaluate Veo™ as an improved method when compared to adaptive statistical iterative reconstruction (ASIR™) for the depiction of small vessels on pediatric CT. MATERIALS AND METHODS: Seventeen patients (mean age: 3.4 years, range: 2 days to 10.0 years; 6 girls, 11 boys) underwent contrast-enhanced CT examinations of the chest and abdomen in this HIPAA compliant and institutional review board approved study. Raw data were reconstructed into separate image datasets using Veo™ and ASIR™ algorithms (GE Medical Systems, Milwaukee, WI). Four blinded radiologists subjectively evaluated image quality. The pulmonary, hepatic, splenic and renal arteries were evaluated for the length and number of branches depicted. Datasets were compared with parametric and non-parametric statistical tests. RESULTS: Readers stated a preference for Veo™ over ASIR™ images when subjectively evaluating image quality criteria for vessel definition, image noise and resolution of small anatomical structures. The mean image noise in the aorta and fat was significantly less for Veo™ vs. ASIR™ reconstructed images. Quantitative measurements of mean vessel lengths and number of branches vessels delineated were significantly different for Veo™ and ASIR™ images. Veo™ consistently showed more of the vessel anatomy: longer vessel length and more branching vessels. CONCLUSION: When compared to the more established adaptive statistical iterative reconstruction algorithm, model-based iterative reconstruction appears to produce superior images for depiction of small pediatric vessels on computed tomography.

Intra-abdominal inverted umblical cord in gastroschisis: a unique ultrasound finding.

A relatively new surgical technique allows for sutureless closure of a gastroschisis defect. Immediately after birth, a long umbilical cord stump is temporarily inverted into the abdominal cavity and later retracted and used to close the abdominal wall defect. Knowledge of this entity is important since the inverted umbilical cord simulates an intra-abdominal mass on cross-sectional imaging. While this procedure is well described in the surgical literature, the imaging features of inverted umbilical cord have yet to be reported. The case presented here highlights the sonographic imaging findings of the umbilical cord during the intestinal decompression phase of sutureless repair of gastroschisis.

The prevalence and patterns of intraluminal air in acute appendicitis at CT.

The purpose of this study is to investigate if the presence and distribution of intraluminal air in the appendix contributes to the computed tomography (CT) diagnosis of appendicitis. We identified 100 consecutive patients (57 men and 43 women; mean age, 38) with CT prior to appendectomy for acute appendicitis over a 5-year period and a control group of 100 consecutive patients (29 men and 71 women; mean age, 39) who underwent CT for acute abdominal pain without appendicitis. Patients were scanned using multidetector row CT scanners at 1.25 or 5-mm slice thickness, peak tube voltage of 120 kVp, and milliamperse automatically adjusted to attain a noise index of 12. Ninety-two of 100 study patients and 95 of 100 controls received 150 mL intravenous contrast. Two independent readers noted the presence and distribution pattern of intraluminal air in the appendix, appendiceal diameter, wall hyperemia, wall thickening (>3 mm), and wall stratification and presence of any secondary signs of appendicitis including fat stranding and free fluid. Data were compared between groups using Fisher's exact test and Student's t test. Intraluminal air in the appendix was more common in control patients versus patients with appendicitis (66 of 100 versus 27 of 100, p < 0.001). No significant differences in the patterns of intraluminal air were found between cases and controls. Among appendicitis cases, there was no significant difference in mean appendiceal diameter (12.8 versus 12.0, p = 0.20) or number of CT signs of appendicitis (1.93 versus 1.86, p = 0.78) in cases with intraluminal air versus without. No case of appendicitis demonstrated intraluminal air without secondary signs of appendicitis. Although intraluminal air is sometimes assumed to exclude a diagnosis of appendicitis, it is actually a common finding seen in up to 27 % of cases at CT. The pattern of intraluminal air was not helpful in differentiating a normal appendix from appendicitis.

Imaging of müllerian duct anomalies.

The müllerian ducts are paired embryologic structures that undergo fusion and resorption in utero to give rise to the uterus, fallopian tubes, cervix, and upper two-thirds of the vagina. Interruption of normal development of the müllerian ducts can result in formation of müllerian duct anomalies (MDAs). MDAs are a broad and complex spectrum of abnormalities that are often associated with primary amenorrhea, infertility, obstetric complications, and endometriosis. MDAs are commonly associated with renal and other anomalies; thus, identification of both kidneys is important. However, MDAs are not associated with ovarian anomalies. Hysterosalpingography (HSG) is routinely used in evaluation of infertility. Because a key component of MDA characterization is the external uterine fundal contour, HSG is limited for this purpose. Patients suspected of having an MDA are often initially referred for pelvic ultrasonography (US). Magnetic resonance (MR) imaging is typically reserved for complex or indeterminate cases. MR imaging is the imaging standard of reference because it is noninvasive, does not involve ionizing radiation, has multiplanar capability, allows excellent soft-tissue characterization, and permits a greater field of interrogation than does US. Use of MR imaging for evaluation of MDAs reduces the number of invasive procedures and related costs by guiding management decisions.

Targeted MRI contrast agents for pediatric hepatobiliary disease.

New options are available for the magnetic resonance imaging (MRI) assessment of pediatric hepatobiliary disease. This article describes the potential utility for MRI with contrast agents tailored for hepatobiliary imaging. MRI contrast agents that preferentially target the liver may be helpful in characterizing liver masses and bile duct abnormalities in select children. The imaging approach is noninvasive and relatively rapid to perform. It also provides anatomic and functional information and is a radiation-free alternative to other imaging strategies. This relatively new imaging procedure is placed in the context of more established imaging modalities. The pharmacokinetics, technical considerations, and potential applications of these hepatobiliary-specific contrast agents also are discussed.

Ureteral injury following anterior thoracolumbar spinal instrumented fusion for adolescent idiopathic scoliosis: a case report with CT angiography analysis of surgically relevant anatomy.

PURPOSE: To report a rare ureteral injury following anterior spinal fusion for adolescent idiopathic scoliosis (AIS) that resulted in complete nephrectomy and to delineate the anatomical relationship between the proximal ureter and the anterior lumbar spine based on CT angiography (CTA). METHODS: Thoracolumbar spine CTAs of children with AIS were reviewed. We measured the following relationships to the ureters: lateral-most aspect of vertebral body, anterior psoas at intervertebral disc/vertebral body levels, and lateral psoas at vertebral body level. Spine level at which the renal arteries originated from the aorta was identified. Distance from origin to corresponding vertebral body/intervertebral disc also was measured. RESULTS: Forty-one girls and seven boys (mean age 12 years, range 7-18) were analyzed. Scoliosis lumbar convexity was left 94% and right 6%. From L1 to L4, ureter was identified within 1-2 cm of vertebral body. Distance between ureter and vertebral body and ureter and anterior psoas at intervertebral disc/vertebral body levels was less on left vs. right from L1 to L4 (p < 0.0001). Distance between ureter and lateral psoas was less on left vs. right from L1 to L2 (p = 0.0205; p = 0.0132) and greater on left vs. right from L3 to L4 (p = 0.0022; p = 0.0076). Renal artery originated at L1/L2 in > 50%. There was no difference in distance from renal artery origin to vertebral body/intervertebral disc (p = 0.4764). CONCLUSION: Ureteral injury is a potentially morbid complication of anterior spine surgery. Injury can occur secondary to disrupted blood supply and mechanical tissue damage. Surgeons must clearly understand the juxta-spinal anatomy to limit dissection and modify retraction to reduce risk. LEVEL OF EVIDENCE: Level IV.

How Much Does Lead Shielding during Fluoroscopy Reduce Radiation Dose to Out-of-Field Body Parts?

BACKGROUND: Fluoroscopy technologists routinely place a lead shield between the x-ray table and the patient's gonads, even if the gonads are not directly in the x-ray field. Internal scatter radiation is the greatest source of radiation to out-of-field body parts, but a shield placed between the patient and the x-ray source will not block internal scatter. Prior nonfluoroscopy research has shown that there is a small reduction in radiation dose when shielding the leakage radiation that penetrates through the collimator shutters. The goal of this in vitro study was to determine if there was any radiation dose reduction when shielding leakage radiation during fluoroscopy. METHODS: This was an in vitro comparison study of radiation doses using different collimation and shielding strategies during fluoroscopy. Ionization chamber measurements were obtained during fluoroscopy of an acrylic block with and without collimation and shielding. Ionization chamber readings were taken in-field at 0 cm and out-of-field at 7.5, 10, and 12.5 cm from beam center. RESULTS: Collimation reduced 87% of the out-of-field radiation dose, and the remaining measurable dose was because of internal scatter. The radiation dose contribution from leakage radiation was negligible, as there was not any measurable radiation dose difference when shielding leakage radiation, with P value of .48. CONCLUSION: These results call into question the clinical utility of routinely shielding out-of-field body parts during fluoroscopy.

Detection of bowel inflammation with fused DWI/T2 images versus contrast-enhanced images in pediatric MR enterography with histopathologic correlation.

PURPOSE: To evaluate the fused, colorized diffusion weighted imaging (DWI) and anatomic T2 images compared to routine contrast-enhanced T1 images at pediatric magnetic resonance enterography (MRE). METHODS: Fused, colorized DWI/T2 images were created from patients with magnetic resonance enterography (MRE) and colonoscopy/biopsy. Radiologists noted inflammation in five bowel segments (terminal ileum-rectosigmoid colon) on postcontrast images and DWI/T2 images. Test characteristics and agreement were calculated. RESULTS: For 20 patients, sensitivity/specificity/positive predictive value (PPV)/negative predictive value (NPV) were 0.53/0.90/0.77/0.76 for DWI/T2 and 0.45/0.90/0.72/0.73 for postcontrast images. Intraobserver agreement was Ò¡=0.45-0.73. Interobserver agreement was Ò¡=0.53 for DWI/T2 and Ò¡=0.63 for postcontrast images. CONCLUSION: DWI/T2 images are similar in sensitivity/specificity to contrast-enhanced images and with moderate intra/interobserver reliability.

Magnetic resonance imaging findings in juvenile spondyloarthropathy and effects of treatment observed on subsequent imaging.

BACKGROUND: Magnetic resonance imaging (MRI) is often used to diagnose and monitor treatment effects of juvenile spondyloarthropathy (SpA). Our objective was to describe MRI findings in juvenile SpA and determine predictors of active sacroiliitis and response to treatment. METHODS: Children who had MRI of the sacroiliac (SI) joints and were referred to the pediatric rheumatology clinic from 2009 to 2012 were retrospectively studied. The clinical parameters, laboratory studies and findings on MRI were collected and a composite score ratio (CR) was calculated for both SI joints on each MRI study based on a semi-quantitative scale that included evaluation of bone marrow edema (BME), synovial enhancement (SE), and erosions (ER). The findings on MRI were correlated with clinical and laboratory values. RESULTS: 50 subjects who underwent 76 MRI for suspected or known SpA were included in the study. Sacroiliitis was seen in 48 MRIs in 32 subjects. Of the subjects with sacroiliitis, mean age ± standard deviation was 13.7 ± 2.6 years, 71% were male and 41% were HLA B27 positive. SE without BME was seen in 31% cases of sacroiliitis. In subjects with sacroiliitis, 79% also had hip arthritis and 41% had enthesitis of the pelvic region on MRI. In 38% of subjects with sacroiliitis, physical exam was not indicative of sacroiliitis or hip arthritis. Longitudinal data were available for 13 subjects. Sacroiliitis on MRI improved in 9 subjects with the greatest improvement in MRI composite score ratio after initiation of etanercept therapy. CR improvement was due to improvement of BME and SE components, while the ER score remained the same or worsened in all but 1 subject. CONCLUSION: History, physical exam or laboratory data may not predict sacroiliitis in children. Magnetic resonance imaging plays a valuable role in the initial evaluation and later treatment monitoring of children with spondyloarthropathy. Synovial enhancement is significantly reduced after treatment, and unlike adults, synovial enhancement may be detected without accompanying bone marrow edema, which suggests gadolinium contrast may be an important component in the assessment of children with spondyloarthropathy.

Disodium gadoxetate uptake in progressive familial intrahepatic cholestasis type I: Enhancing our understanding of the cholestatic disease.

Hepatocyte-specific magnetic resonance imaging (MRI) contrast agents are commonly used to depict anatomic hepatobiliary lesions and are also useful in characterizing the kinetics of hepatocyte uptake and excretion. We report a case of a 13-year old female with progressive familial intrahepatic cholestasis (PFIC) type 1 who demonstrated decreased uptake and excretion of gadoxetate disodium contrast material. This case illustrates the challenge of imaging children with cholestasis using hepatobiliary-specific contrast agents; we propose an alternative explanation for the delayed excretion that may be related to the underlying genetic defect of this child.