White matter microstructural changes during the first three years of healthy brain development are characterized using two different models developed for limited clinical diffusion data: White Matter ...Tract Integrity (WMTI) metrics from Diffusional Kurtosis Imaging (DKI) and Neurite Orientation Dispersion and Density Imaging (NODDI). Both models reveal a non-linear increase in intra-axonal water fraction and in tortuosity of the extra-axonal space as a function of age, in the genu and splenium of the corpus callosum and the posterior limb of the internal capsule. The changes are consistent with expected behavior related to myelination and asynchrony of fiber development. The intra- and extracellular axial diffusivities as estimated with WMTI do not change appreciably in normal brain development. The quantitative differences in parameter estimates between models are examined and explained in the light of each model's assumptions and consequent biases, as highlighted in simulations. Finally, we discuss the feasibility of a model with fewer assumptions.
In this article, the authors discuss the development and current curriculum of the Art in Medicine course at the University of Colorado School of Medicine (CUSOM), developed in collaboration with the ...Centre for Bioethics and Humanities, and the Denver Art Museum. Examples of art museum-based techniques implemented with medical students are discussed with objectives, methods, and pedagogy highlighted. Translational skillsets for medical professionals, including empathy, tolerance of ambiguity, perspective taking, bias, and communication are emphasised through practice in engagement in visual arts with facilitation by medical faculty and art museum educators. Following the discussion of classroom based activities, two of the co-authors, physician-educators from the CUSOM Departments of Medicine and Radiology, discuss the direct applications and importance of these skillsets in the context of the exam room and the reading room respectively.
Neuroimaging of the preterm infant is a common assessment performed in the NICU. Timely and focused studies can be used for diagnostic, therapeutic, and prognostic information. However, significant ...variability exists among neonatal units as to which modalities are used and when imaging studies are obtained. Appropriate timing and selection of neuroimaging studies can help identify neonates with brain injury who may require therapeutic intervention or who may be at risk for neurodevelopmental impairment. This clinical report reviews the different modalities of imaging broadly available to the clinician. Evidence-based indications for each modality, optimal timing of examinations, and prognostic value are discussed.
Congenital limb length discrepancy disorders are frequently associated with a variety of vascular anomalies and have unique genetic and phenotypic features. Many of these syndromes have been linked ...to sporadic somatic mosaicism involving mutations of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, which has an important role in tissue growth and angiogenesis. Radiologists who are aware of congenital limb length discrepancies can make specific diagnoses based on imaging findings. Although genetic confirmation is necessary for a definitive diagnosis, the radiologist serves as a central figure in the identification and treatment of these disorders. The clinical presentations, diagnostic and imaging workups, and treatment options available for patients with Klippel-Trenaunay syndrome, CLOVES (congenital lipomatous overgrowth, vascular anomalies, epidermal nevi, and scoliosis/spinal deformities) syndrome, fibroadipose vascular anomaly, phosphatase and tensin homolog mutation spectrum, Parkes-Weber syndrome, and Proteus syndrome are reviewed.
RSNA, 2019.
The rate of anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) in ovarian teratomas is unknown. We aim to identify the prevalence of NMDARE as well as volumetric and histopathologic ...characteristics of ovarian teratomas in patients with versus without.
We performed a retrospective cohort study to identify patients with confirmed ovarian teratomas and the characteristics of teratomas in NMDARE compared with non-NMDARE patients. Patients aged between 0 and 21 years with confirmed histopathological diagnosis of ovarian teratoma after resection were included. The rate of NMDARE in ovarian teratomas was identified. Moreover, volumes of ovarian teratomas and the frequency of neuronal glial elements on histopathology in NMDARE versus non-NMDARE patients were assessed.
Five out of one-hundred-and-sixty-three (3.07%) patients with histopathology confirmed ovarian teratomas were diagnosed with NMDARE. Age was not different between the NMDARE (mean: 13.8 years, standard deviation: 3.9) and non-NMDARE groups (median: 14, interquartile range IQR: 5). Teratoma volumes from NMDARE patients were smaller than those of non-NMDARE patients (median 28.3 cm
with IQR of 431.2 and median 182.8 with IQR of 635.0, respectively). Both age and NMDARE diagnosis were statistically significant variables in the analysis of variance on a multiple linear regression model. Age (
= 0.013) had a positive correlation with teratoma size, whereas presence of NMDARE had a negative correlation (
= 0.008).
The rate of NMDARE in ovarian teratomas is low and NMDARE patients have smaller teratomas than non-NMDARE. Further studies are needed to understand the timing of anti-NMDA receptor antibodies in teratomas and the development of NMDARE.
Background
Artificial intelligence models have been successful in analyzing ordinary photographic images. One type of artificial intelligence model is object detection, where a labeled bounding box ...is drawn around an area of interest. Object detection can be applied to medical imaging tasks.
Objective
To demonstrate object detection in identifying rickets and normal wrists on pediatric wrist radiographs using a small dataset, simple software and modest computer hardware.
Materials and methods
The institutional review board at Children’s Healthcare of Atlanta approved this study. The radiology information system was searched for radiographic examinations of the wrist for the evaluation of rickets from 2007 to 2018 in children younger than 7 years of age. Inclusion criteria were an exam type of “Rickets Survey” or “Joint Survey 1 View” with reports containing the words “rickets” or “rachitic.” Exclusion criteria were reports containing the words “renal,” “kidney” or “transplant.” Two pediatric radiologists reviewed the images and categorized them as either rickets or normal. Images were annotated by drawing a labeled bounding box around the distal radial and ulnar metaphases. The training dataset was created from images acquired from Jan. 1, 2007, to Dec. 31, 2017. This included 104 wrists with rickets and 264 normal wrists. This training dataset was used to create the object detection model. The testing dataset consisted of images acquired during the 2018 calendar year. This included 20 wrists with rickets and 37 normal wrists. Model sensitivity, specificity and accuracy were measured.
Results
Of the 20 wrists with rickets in the testing set, 16 were correctly identified as rickets, 2 were incorrectly identified as normal and 2 had no prediction. Of the 37 normal wrists, 33 were correctly identified as normal, 2 were incorrectly identified as rickets and 2 had no prediction. This yielded a sensitivity and specificity of 80% and 95% for wrists with rickets and 89% and 90% for normal wrists. Overall model accuracy was 86%.
Conclusion
Object detection can identify rickets on pediatric wrist radiographs. Object detection models can be developed with a small dataset, simple software tools and modest computing power.
This article describes the development and assessment of a neuroimaging curriculum for neonatology fellows. The curriculum is focused on topics that are relevant to the practice of neonatology and ...employs contemporary teaching methods, such as flipped classroom, learner engagement, and spaced repetition. Since its implementation 2018 the curriculum has been appreciated by our trainees and demonstrated improvements in trainee knowledge.
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