Impact of a fast free-breathing 3-T abdominal MRI protocol on improving scan time and image quality for pediatric patients with tuberous sclerosis complex.

BACKGROUND: Magnetic resonance imaging (MRI) of the abdomen can be especially challenging in pediatric patients because of image quality degradation from respiratory motion. Abdominal MR protocols tailored for free-breathing children can potentially improve diagnostic image quality and reduce scan time. OBJECTIVE: To evaluate the performance of a free-breathing 3-T MRI protocol for renal evaluation in pediatric patients with tuberous sclerosis complex (TSC). MATERIALS AND METHODS: A single institution, Institutional Review Board-approved, retrospective database query identified pediatric TSC patients who underwent a free-breathing 3-T MR abdominal protocol including radial and respiratory-triggered pulse sequences and who also had a prior abdominal MRI on the same scanner using a traditional MR protocol utilizing signal averaging and Cartesian k-space sampling. Scan times and use of sedation were recorded. MR image quality was compared between the two protocols using a semiquantitative score for overall image quality and sharpness. RESULTS: Forty abdominal MRI studies in 20 patients were evaluated. The mean scan time of the fast free-breathing protocol was significantly lower (mean: 42.5±9.8 min) compared with the traditional protocol (58.7±11.7 min; P=<0.001). Image sharpness was significantly improved for radial T2-weighted and T1-weighted triggered Dixon and radial T1-weighted fat-suppressed post-contrast images in the free-breathing protocol, while image quality was significantly higher on radial and Dixon T1-weighted sequences. CONCLUSION: A free-breathing abdominal MR protocol in pediatric TSC patients decreases scan time and improves image quality and should be considered more widely for abdominal MRI in children.

Artificial intelligence-assisted interpretation of bone age radiographs improves accuracy and decreases variability.

OBJECTIVE: Radiographic bone age assessment (BAA) is used in the evaluation of pediatric endocrine and metabolic disorders. We previously developed an automated artificial intelligence (AI) deep learning algorithm to perform BAA using convolutional neural networks. We compared the BAA performance of a cohort of pediatric radiologists with and without AI assistance. MATERIALS AND METHODS: Six board-certified, subspecialty trained pediatric radiologists interpreted 280 age- and gender-matched bone age radiographs ranging from 5 to 18 years. Three of those radiologists then performed BAA with AI assistance. Bone age accuracy and root mean squared error (RMSE) were used as measures of accuracy. Intraclass correlation coefficient evaluated inter-rater variation. RESULTS: AI BAA accuracy was 68.2% overall and 98.6% within 1 year, and the mean six-reader cohort accuracy was 63.6 and 97.4% within 1 year. AI RMSE was 0.601 years, while mean single-reader RMSE was 0.661 years. Pooled RMSE decreased from 0.661 to 0.508 years, all individually decreasing with AI assistance. ICC without AI was 0.9914 and with AI was 0.9951. CONCLUSIONS: AI improves radiologist's bone age assessment by increasing accuracy and decreasing variability and RMSE. The utilization of AI by radiologists improves performance compared to AI alone, a radiologist alone, or a pooled cohort of experts. This suggests that AI may optimally be utilized as an adjunct to radiologist interpretation of imaging studies to improve performance.

Comparison of CT enterography and MR enterography imaging features of active Crohn disease in children and adolescents.

BACKGROUND: Assessment for active Crohn disease by CT enterography and MR enterography relies on identifying mural and perienteric imaging features. OBJECTIVE: To evaluate the performance of established imaging features of active Crohn disease in children and adolescents on CT and MR enterography compared with histological reference. MATERIALS AND METHODS: We included patients ages 18 years and younger who underwent either CT or MR enterography from 2007 to 2014 and had endoscopic biopsy within 28 days of imaging. Two pediatric radiologists blinded to the histological results reviewed imaging studies and scored the bowel for the presence or absence of mural features (wall thickening >3 mm, mural hyperenhancement) and perienteric features (mesenteric hypervascularity, edema, fibrofatty proliferation and lymphadenopathy) of active disease. We performed univariate analysis and multivariate logistic regression to compare imaging features with histological reference. RESULTS: We evaluated 452 bowel segments (135 from CT enterography, 317 from MR enterography) from 84 patients. Mural imaging features had the highest association with active inflammation both for MR enterography (wall thickening had 80% accuracy, 69% sensitivity and 91% specificity; mural hyperenhancement had 78%, 53% and 96%, respectively) and CT enterography (wall thickening had 84% accuracy, 72% sensitivity and 91% specificity; mural hyperenhancement had 76%, 51% and 91%, respectively), with perienteric imaging features performing significantly worse on MR enterography relative to CT enterography (P < 0.001). CONCLUSION: Mural features are predictors of active inflammation for both CT and MR enterography, while perienteric features can be distinguished better on CT enterography compared with MR enterography. This likely reflects the increased conspicuity of the mesentery on CT enterography and suggests that mural features are the most reliable imaging features of active Crohn disease in children and adolescents.

Meniscus morphology: Does tear type matter? A narrative review with focus on relevance for osteoarthritis research.

OBJECTIVE: To give a narrative overview of meniscal tears with a radiologic emphasis on the morphologic type, technical considerations, and on the relevance of the type of meniscal tear in the context of osteoarthritis (OA) research. DESIGN: Total 20 years of the PubMed database were searched for epidemiological, radiological, arthroscopic and biomechanical reports, and review articles focusing on meniscal tears in middle-aged and older individuals, in the setting of OA. Case reports, publications on meniscal tears in young active individuals, and publications not in English were excluded. RESULTS: Meniscal intra-substance signal abnormalities are associated with an increased risk of a degenerative meniscal tear in the same segment. Posterior radial tears of the medial meniscus appear to be a highly relevant event in OA of the knee, with associated cartilage loss and meniscal extrusion. Radial tears are more commonly missed on MRI than other types, and should be carefully looked for on coronal and axial images. While medial meniscus posterior root tears are of "radial" morphology, there is growing interest in looking at them as a separate entity, mainly because they require a different therapeutic approach. CONCLUSION: There is a lack of data on the relevance of different morphologic types of meniscal tears to the natural history of knee OA, both cross-sectionally and-especially-longitudinally. Further epidemiologic studies should focus on specific meniscal tears based on their morphology to better understand their relevance in the genesis and progression of knee OA.

Continuous aspiration prior to intracranial vascular embolectomy (CAPTIVE): a technique which improves outcomes.

BACKGROUND: Modern stent retriever-based embolectomy for patients with emergent large vessel occlusion improves outcomes. Techniques aimed at achieving higher rates of complete recanalization would benefit patients. OBJECTIVE: To evaluate the clinical impact of an embolectomy technique focused on continuous aspiration prior to intracranial vascular embolectomy (CAPTIVE). METHODS: A retrospective review was performed of 95 consecutive patients with intracranial internal carotid artery or M1 segment middle cerebral artery occlusion treated with stent retriever-based thrombectomy over an 11-month period. Patients were divided into a conventional local aspiration group (traditional group) and those treated with a novel continuous aspiration technique (CAPTIVE group). We compared both early neurologic recovery (based on changes in National Institute of Health Stroke Scale (NIHSS) score), independence at 90 days (modified Rankin score 0-2), and angiographic results using the modified Thrombolysis in Cerebral Ischemia (TICI) scale including the TICI 2c category. RESULTS: There were 56 patients in the traditional group and 39 in the CAPTIVE group. Median age and admission NIHSS scores were 78 years and 19 in the traditional group and 77 years and 19 in the CAPTIVE group. Median times from groin puncture to recanalization in the traditional and CAPTIVE groups were 31 min and 14 min, respectively (p<0.0001). While rates of TICI 2b/2c/3 recanalization were similar (81% traditional vs 100% CAPTIVE), CAPTIVE offered higher rates of TICI 2c/3 recanalization (79.5% vs 40%, p<0.001). Median discharge NIHSS score was 10 in the traditional group and 3 in the CAPTIVE group; this difference was significant. There was also an increased independence at 90 days (25% traditional vs 49% CAPTIVE). CONCLUSIONS: The CAPTIVE embolectomy technique may result in higher recanalization rates and better clinical outcomes.

Abdominal ultrasonography of the pediatric gastrointestinal tract.

Ultrasound is an invaluable imaging modality in the evaluation of pediatric gastrointestinal pathology; it can provide real-time evaluation of the bowel without the need for sedation or intravenous contrast. Recent improvements in ultrasound technique can be utilized to improve detection of bowel pathology in children: Higher resolution probes, color Doppler, harmonic and panoramic imaging are excellent tools in this setting. Graded compression and cine clips provide dynamic information and oral and intravenous contrast agents aid in detection of bowel wall pathology. Ultrasound of the bowel in children is typically a targeted exam; common indications include evaluation for appendicitis, pyloric stenosis and intussusception. Bowel abnormalities that are detected prenatally can be evaluated after birth with ultrasound. Likewise, acquired conditions such as bowel hematoma, bowel infections and hernias can be detected with ultrasound. Rare bowel neoplasms, vascular disorders and foreign bodies may first be detected with sonography, as well. At some centers, comprehensive exams of the gastrointestinal tract are performed on children with inflammatory bowel disease and celiac disease to evaluate for disease activity or to confirm the diagnosis. The goal of this article is to review up-to-date imaging techniques, normal sonographic anatomy, and characteristic sonographic features of common and uncommon disorders affecting the gastrointestinal tract in children.

Expected Sonographic Appearance of the Spleen in Children and Young Adults With Sickle Cell Disease: An Update.

OBJECTIVES: To update the imaging literature regarding spleen appearances in young patients with sickle cell disease (SCD). METHODS: We conducted a retrospective study and included 112 patients age 0 to 21 years with SCD who had at least 1 abdominal sonogram at our institution between 1999 and 2011. Radiologic findings were compared between risk groups by χ(2) analysis. Findings were correlated with other imaging modalities when available. RESULTS: In our cohort, 35.7% of patients had autosplenectomy, and 8.0% had undergone surgical splenectomy. Only 5.0% of individuals age 0 to 5 years had autosplenectomy. In those who had not undergone surgical splenectomy or autosplenectomy, 76.2% had echogenic spleens, heterogeneous-appearing spleens, or both, and patients with the homozygous sickle cell anemia (HbSS) genotype were more likely to have an abnormal spleen echo texture. Patients treated with transfusions had echogenic spleens and had a higher frequency of splenic regeneration nodules. Most patients (80%) with splenomegaly did not require surgical splenectomy after 5.7 years of follow-up. CONCLUSIONS: Twenty years ago, children with HbSS SCD were expected to have autosplenectomy by age 5 years. There have been changes in the radiologic appearance of the spleen in patients with SDC, likely due to improved supportive care and the use of acute and chronic transfusion therapy. We found that autosplenectomy is rare by age 5 years, and during childhood and adolescence, the spleen typically appears echogenic, heterogeneous, or both, depending on disease severity.

MR-arthrography and CT-arthrography in sports-related glenolabral injuries: a matched descriptive illustration.

The combination of a large range of motion and insufficient bony stabilization makes the glenohumeral joint susceptible to injuries including dislocation in young athletes. Magnetic resonance arthrography (MR-arthrography) and computed tomography arthrography (CT-arthrography) play an important role in the preoperative workup of labroligametous injuries. This paper illustrates MR-arthrography and CT-arthrography findings acquired at the same time on the same subjects to illustrate common causes and sequelae of shoulder instability. Teaching Points • MR-arthrography and CT-arthrography are equivalent for SLAP and full-thickness rotator cuff tears.• CT-arthrography is superior in evaluating osseous defects and cartilage surface lesions.• MR-arthrography is superior in evaluating intrasubstance and extra-articular tendinous injuries.

Implications of radiologic-pathologic correlation for gallbladder disease in children and young adults with sickle cell disease.

The purpose of this study is to describe gallbladder imaging findings in patients with sickle cell disease, and to determine how they correspond with occurrence of complications, need for cholecystectomy, and surgical pathology. This study is IRB approved and HIPAA compliant. Informed consent requirements were waived. We reviewed records of 77 children with sickle cell disease ages 0-18 years at the time of their first gallbladder imaging study. Demographics, hospital courses, and radiologic and pathologic reports were collected. Two pediatric radiologists independently and retrospectively reviewed the imaging studies. Statistical analysis was performed using kappa statistic, chi-squared test, and ANOVA F-test. Continuous variables were described with mean, median, variance, and range. Patients who underwent cholecystectomy (N = 25) were more likely than the patients who did not undergo cholecystectomy (N = 52) to have gallstones or sludge (100 versus 36.5 %, p = <0.0001) or other gallbladder or biliary abnormality (70.8 versus 1.9 %, p = <0.0001). Patients who did not undergo cholecystectomy more frequently had normal-appearing gallbladders and biliary tracts (63.5 versus 0 %, p = <0.0001). Ninety-two percent of patients with cholecystectomy had chronic cholecystitis on pathology, and 96 % had a complication, including chronic cholecystitis and sequelae of biliary obstruction. Young patients with sickle cell disease, cholelithiasis, and any other biliary imaging abnormality will almost certainly require cholecystectomy, and many will experience complications. The most common surgical pathologic diagnosis in this group is chronic cholecystitis, which has a variable radiologic appearance. Our findings support recommendations to perform elective cholecystectomy for children and young adults with sickle cell disease and cholelithiasis or gallbladder sludge.