3T Magnetic Resonance Imaging Research Articles

Automated magnetic resonance imaging-based grading of the lumbar intervertebral disc and facet joints.

Degeneration of both intervertebral discs (IVDs) and facet joints in the lumbar spine has been associated with low back pain, but whether and how IVD/joint degeneration contributes to pain remains an open question. Joint degeneration can be identified by pairing T1 and T2 magnetic resonance imaging (MRI) with analysis techniques such as Pfirrmann grades (IVD degeneration) and Fujiwara scores (facet degeneration). However, these grades are subjective, prompting the need to develop an automated technique to enhance inter-rater reliability. This study introduces an automated convolutional neural network (CNN) technique trained on clinical MRI images of IVD and facet joints obtained from public-access Lumbar Spine MRI Dataset. The primary goal of the automated system is to classify health of lumbar discs and facet joints according to Pfirrmann and Fujiwara grading systems and to enhance inter-rater reliability associated with these grading systems. Performance of the CNN on both the Pfirrmann and Fujiwara scales was measured by comparing the percent agreement, Pearson's correlation and Fleiss kappa value for results from the classifier to the grades assigned by an expert grader. The CNN demonstrates comparable performance to human graders for both Pfirrmann and Fujiwara grading systems, but with larger errors in Fujiwara grading. The CNN improves the reliability of the Pfirrmann system, aligning with previous findings for IVD assessment. The study highlights the potential of using deep learning in classifying the IVD and facet joint health, and due to the high variability in the Fujiwara scoring system, highlights the need for improved imaging and scoring techniques to evaluate facet joint health. All codes required to use the automatic grading routines described herein are available in the Data Repository for University of Minnesota (DRUM).

Deep Learning Assisted Classification of T1ρ-MR Based Intervertebral Disc Degeneration Phases.

According to the T1ρ value of nucleus pulposus, our previous study has found that intervertebral disc degeneration (IDD) can be divided into three phases based on T1ρ-MR, which is helpful for the selection of biomaterial treatment timing. However, the routine MR sequences for patients with IDD are T1- and T2-MR, T1ρ-MR is not commonly used due to long scanning time and extra expenses, which limits the application of T1ρ-MR based IDD phases. To build a deep learning model to achieve the classification of T1ρ-MR based IDD phases from routine T1-MR images. Retrospective. Sixty (M/F: 35/25) patients with low back pain or lower limb radiculopathy are randomly divided into training (N = 50) and test (N = 10) sets. 1.5 T MR scanner; T1-, T2-, and T1ρ-MR sequence (spin echo). The T1ρ values of the nucleus pulposus in intervertebral discs (IVDs) were measured. IVDs were divided into three phases based on the mean T1ρ value: pre-degeneration phase (mean T1ρ value >110 msec), rapid degeneration phase (mean T1ρ value: 80-110 msec), and late degeneration phase (mean T1ρ value <80 msec). After measurement, the T1ρ values, phases, and levels of IVDs were input into the model as labels. Intraclass correlation coefficient, area under the receiver operating characteristic curve (AUC), F1-score, accuracy, precision, and recall (P < 0.05 was considered significant). In the test dataset, the model achieved a mean average precision of 0.996 for detecting IVD levels. The diagnostic accuracy of the T1ρ-MR based IDD phases was 0.840 and the AUC was 0.871, the average AUC of 5-folds cross validation was 0.843. The proposed deep learning model achieved the classification of T1ρ-MR based IDD phases from routine T1-MR images, which may provide a method to facilitate the application of T1ρ-MR in IDD. 4 TECHNICAL EFFICACY: Stage 2.

Bimodal MRI/Fluorescence Nanoparticle Imaging Contrast Agent Targeting Prostate Cancer.

We developed a novel site-specific bimodal MRI/fluorescence nanoparticle contrast agent targeting gastrin-releasing peptide receptors (GRPrs), which are overexpressed in aggressive prostate cancers. Biocompatible ultra-small superparamagnetic iron oxide (USPIO) nanoparticles were synthesized using glucose and casein coatings, followed by conjugation with a Cy7.5-K-8AOC-BBN [7-14] peptide conjugate. The resulting USPIO(Cy7.5)-BBN nanoparticles were purified by 100 kDa membrane dialysis and fully characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, and magnetic resonance imaging (MRI) relaxivity, as well as evaluated for in vitro and in vivo binding specificity and imaging efficacy in PC-3 prostate cancer cells and xenografted tumor-bearing mice. The USPIO(Cy7.5)-BBN nanoparticles had a core diameter of 4.93 ± 0.31 nm and a hydrodynamic diameter of 35.56 ± 0.58 nm. The r2 relaxivity was measured to be 70.2 ± 2.5 s-1 mM-1 at 7T MRI. The Cy7.5-K-8AOC-BBN [7-14] peptide-to-nanoparticle ratio was determined to be 21:1. The in vitro GRPr inhibitory binding (IC50) value was 2.5 ± 0.7 nM, indicating a very high binding affinity of USPIO(Cy7.5)-BBN to the GRPr on PC-3 cells. In vivo MRI showed significant tumor-to-muscle contrast enhancement in the uptake group at 4 h (31.1 ± 3.4%) and 24 h (25.7 ± 2.1%) post-injection compared to the blocking group (4 h: 15.3 ± 2.0% and 24 h: -2.8 ± 6.8%; p < 0.005). In vivo and ex vivo near-infrared fluorescence (NIRF) imaging revealed significantly increased fluorescence in tumors in the uptake group compared to the blocking group. These findings demonstrate the high specificity of bimodal USPIO(Cy7.5)-BBN nanoparticles towards GRPr-expressing PC-3 cells, suggesting their potential for targeted imaging in aggressive prostate cancer.

MicroRNA and renal fibrosis in autosomal dominant polycystic kidney disease: a longitudinal study.

Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary kidney disorder that may progress to kidney failure, accounting for 5-10% of all patients with end-stage kidney disease (ESKD). Clinical data, as well as molecular genetics and advanced imaging techniques have provided surrogate prognostic biomarkers to predict rapid decline in kidney function, nonetheless enhanced tools for assessing prognosis for ADPKD are stillneeded. The aim of this study was to analyze specific microRNAs involved in the pathogenesis of ADPKD and in the development of renal fibrosis, evaluating their potential role as predictors of renal function loss. We evaluated kidney function by estimated glomerular filtration rate (eGFR) in 32 ADPKD patients in different stages of kidney disease at T0 and after a 24-month follow up (T1). Patients were divided into two groups: Rapid disease progression ([RP], n 15) and Non-rapid disease progression ([NRP], n 17), according to the Mayo Clinic classification criteria. At T0, ADPKD patients underwent plasma sampling for quantitative analysis of h-miR-17-5p, h-miR-21-5p and h-miR-199a-5p microRNA expression, using the quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) method and a 3T magnetic resonance imaging (MRI), using an advanced MRI imaging protocol, for the quantification of total kidney volume (TKV), total perfusion volume (TPV) and total fibrotic volume (TFV). The expression of h-miR17-5p was higher (p < 0.05) in ADPKD patients with rapid disease progression. h-miR-17-5p, h-miR-21-5p and h-mir-199-5p showed a positive and significant correlation with the eGFR slope (mL/min/1.73 m2/year) (p < 0.05) but not with the eGFR at both T0 and T1. Both total fibrotic volume (cm3) and height-adjusted total fibrotic volume (cm3/m) were positively and significantly correlated to h-miR 21-5p and h-miR 199-5p (p < 0.05), but not to total kidney volume (cm3) and height-adjusted total kidney volume (cm3/m). The microRNAs we studied were associated with fibrosis and renal damage, suggesting their possible role as biomarkers able to identify ADPKD patients at high risk of disease progression regardless of the degree of kidney function, and therefore suitable for medical therapy, and may help uncovering new molecular mechanisms underlying cystogenesis.

Cross-sectional study on the impact of cardiac and hepatic iron overload, as measured by MRI T2*, on the quality of life in children with severe beta-thalassemia major.

A cross-sectional study to explore the correlation between cardiac and hepatic iron overload and its impact on the quality of life in children diagnosed with severe beta-thalassemia major (β-TM). A cohort of 55 pediatric patients with β-TM, diagnosed via genetic testing at the Affiliated Hospital of Guangdong Medical University from January 2015 to January 2022, was included in this study. The assessment of cardiac and hepatic iron overload was conducted using the magnetic resonance imaging T2* technique. The Chinese version of the Pediatric Quality of Life Inventory (PedsQL) 4.0. Pearson correlation analysis was utilized to assess the relationships between the cardiac and hepatic T2* values and between these T2* values and the total scores of PedsQL 4.0. Analysis showed no significant correlation between cardiac and hepatic T2* values. However, a significant relationship was observed between cardiac T2* values and PedsQL 4.0 total scores (r = 0.313, P < .05), indicating that cardiac, but not hepatic, iron overload is associated with the quality of life. This study highlights the absence of correlation between cardiac and hepatic iron overload levels and demonstrates a significant impact of cardiac iron overload on the quality of life in children with β-TM. These findings suggest the need for a focused approach to cardiac health in managing β-TM.

The deltoid ligament complex is reliably visualised as four fascicles in two layers with 3D volumetric MRI in the ankles of 20 asymptomatic volunteers.

The anatomy of the deltoid ligament is complex. There is agreement on the presence of superficial and deep layers but the number and frequency of fascicles remains controversial. Identifying injuries to specific components of the deltoid ligament may inform decision-making on their management. The anatomy was reviewed to establish the number and dimension of fascicles visible with three-dimensional (3D) volumetric magnetic resonance images (MRI). Twenty ankles from asymptomatic healthy volunteers were imaged with 3D volumetric MRI. The presence of individual fascicles was recorded and measured in 3D. The median age of participants was 26 years (range: 20-37) of which 13 (65%) were female. All 20 ankles had a deltoid ligament formed of four fascicles in two layers: three fascicles in the superficial layer; tibionavicular (mean dimensions 22.5 × 10.0 × 2.4 mm), tibiospring (16.6 × 6.7 × 1.9 mm) and tibiocalcaneal (23.8 × 4.6 × 1.8 mm) and a deep layer consisting of the tibiotalar fascicle, which could be divided into two parts: anterior tibiotalar (mean dimensions 10 × 5.6 × 4.1 mm) and the significantly larger posterior tibiotalar (14.2 × 13.8 × 17.5 mm, p < 0.01). There were no additional fascicles observed. The deltoid ligament complex was consistently visualised as four fascicles (tibionavicular, tibiospring, tibiocalcaneal, tibiotalar) in two layers (superficial and deep) in all 20 ankles. The posterior part of the tibiotalar fascicle was the thickest of all the fascicles in the deltoid ligament. It is, therefore, possible to accurately identify the components of the deltoid ligament, and 3T MRI can be used to assess fascicle-specific injury, which will guide treatment and rehabilitation. Level III.

Electric field and SAR reduction in high-impedance RF arrays by using high permittivity materials for 7T MR imaging.

In the field of ultra-high field MR imaging, the challenges associated with higher frequencies and shorter wavelengths necessitate rigorous attention to multichannel array design. While the need for such arrays remains, and efforts to increase channel counts continue, a persistent impediment-inter-element coupling-constantly hinders development. This coupling degrades current and field distribution, introduces noise correlation between channels, and alters the frequency of array elements, affecting image quality and overall performance. The goal of optimizing ultra-high field MRI goes beyond resolving inter-element coupling and includes significant safety considerations related to the design changes required to achieve high-impedance coils. Although these coils provide excellent isolation, the higher impedance needs special design changes. However, such changes pose a significant safety risk in the form of strong electric fields across low-capacitance lumped components. This process may raise Specific Absorption Rate (SAR) values in the imaging subject, increasing power deposition and, as a result, the risk of tissue heating-related injury. To balance the requirement of inter-element decoupling with the critical need for safety, we suggest a new solution. Our method uses high-dielectric materials to efficiently reduce electric fields and SAR values in the imaging sample. This intervention tries to maintain B1 efficiency and inter-element decoupling within the existing array design, which includes high-impedance coils. Our method aims to promote the full potential of ultra-high field MRI by alleviating this critical safety concern with minimal changes to the existing array setup.

Automatic segmentation of the spinal cord nerve rootlets

Abstract Precise identification of spinal nerve rootlets is relevant to delineate spinal levels for the study of functional activity in the spinal cord. The goal of this study was to develop an automatic method for the semantic segmentation of spinal nerve rootlets from T2-weighted magnetic resonance imaging (MRI) scans. Images from two open-access 3T MRI datasets were used to train a 3D multi-class convolutional neural network using an active learning approach to segment C2-C8 dorsal nerve rootlets. Each output class corresponds to a spinal level. The method was tested on 3T T2-weighted images from three datasets unseen during training to assess inter-site, inter-session, and inter-resolution variability. The test Dice score was 0.67 ± 0.16 (mean ± standard deviation across testing images and rootlets levels), suggesting a good performance. The method also demonstrated low inter-vendor and inter-site variability (coefficient of variation ≤ 1.41%), as well as low inter-session variability (coefficient of variation ≤ 1.30%), indicating stable predictions across different MRI vendors, sites, and sessions. The proposed methodology is open-source and readily available in the Spinal Cord Toolbox (SCT) v6.2 and higher.

Brain 3T magnetic resonance imaging in neonates: features and incidental findings from a research cohort enriched for preterm birth

Background and objectivesThe survival rate and patterns of brain injury after very preterm birth are evolving with changes in clinical practices. Additionally, incidental findings can present legal, ethical and practical...

Poster 271: Improving Non-Invasive Diagnosis and Grading of Cartilage Defects in the Knee - Accuracy of Ultra High Field 7-Tesla MRI as Compared with Arthroscopy

Objectives: Osteoarthritis (OA) is a joint disease characterized by degradation of articular cartilage and subchondral bone. Cartilage injury plays an important role in the pathogenesis of osteoarthritis, and disease modifying treatments aiming to preserve and possibly regenerate cartilage are an area of active interest. Early diagnosis is crucial, as the disease may be more responsive to treatment at an early stage, and there is a critical unmet need for improved non-invasive morphologic cartilage imaging techniques. Standard clinical MRI is performed on a 1.5T or 3T machine. Ultra-high field (UHF) 7-Tesla (7T) magnetic resonance imaging (MRI) is a new technology that offers 2.3x improved signal-to noise ratio (SNR) compared to 3T MRI and 2.8x SNR compared to 1.5T MRI. The purpose of this study was to estimate the accuracy of 7T MRI for the detection and grading of cartilage lesions in the knee. The hypothesis was that 7T images would offer better detection and more accurate grading of chondral lesions than standard clinical grade MRI scans. Methods: In this prospective, paired, blinded study, patients who had undergone a 1.5 or 3T standard of care (SOC) MRI and were scheduled for knee arthroscopy were enrolled (10/2019 to 08/2021) and a study intervention 7T MRI was performed prior to surgery. The study was approved by our institutional review board, and it was funded by the Methodist-Siemens Collaboration. Exclusion criteria included contraindication to MRI (e.g., pacemaker), weight less than 30 kg, and pregnancy. Scans were reviewed by three independent fellowship-trained radiologists who were blinded to clinical and arthroscopic data. Scans were reviewed over 5 days, with a 4 week “washout” period between review of SOC and 7T scans to limit recall bias. Readers were blinded to clinical and arthroscopic data and graded all six articular surfaces of the knee (patella, trochlea, lateral condyle, medial condyle, lateral tibia, medial tibia) using a modified Outerbridge classification system. At the time of arthroscopy, each articular surface was graded by the operating surgeon according to a modified Outerbridge system similar to above, with the exception that Grade 1 = softening of the articular cartilage. The surgeon was blinded to 7T images at the time of arthroscopy, although they had access to the SOC MRI, which was necessary for patient care. Using arthroscopy as the gold standard, we calculated sensitivity and specificity of SOC MRI and 7T MRI. An Outerbridge grade of 0 was classified as negative, while a grade of 1-4 was classified as positive. A secondary analysis of sensitivity and specificity was performed on a per articular surface basis, with 6 articular surfaces per patient after correction for within subject clustered data. A Mann-Whitney U test was used to compare diagnostic scores and ratings between instruments (SOC vs. 7T). Coefficients of variation between observers within each instrument were compared for each variable using a paired sample t-test. Type-I error was set at alpha=0.05 Results: A total of 100 patients (age: 43 ± 14, 54 female, 46 male) were enrolled. 7T MRI resulted in improved sharpness (defined by visibility of nerve fascicles) and shading (based on artifacts) compared to SOC MRI (Figure 1, p &lt; 0.001 for both). There was improved contrast between fluid and cartilage with 7T MRI (using confidence rating at axial mid-patella, p = 0.003). 7T MRI had a higher sensitivity in detecting cartilage lesions for five of the six articular surfaces when using the arthroscopic gold standard, but with lower specificity for all surfaces (Figure 2). Finally, there was improved inter-observer reliability in detecting and grading cartilage defects with 7T compared to SOC MRI (p &lt; 0.05). Conclusion: Based on our findings thus far, 7T MRI appears to result in improved measurement ratings, sensitivity, and inter-observer reliability compared to SOC in detecting cartilage lesions in the knee. Further work is needed to evaluate cost effectiveness of 7T MRI.

Hirayama Disease: Neutral and Flexion Magnetic Resonance Imaging Manifestations and Single Tertiary Care Center Analysis on 3T Scanner.

Hirayama disease (HD) is a rare benign type of cervical cord myelopathy occurring commonly in young males as unilateral or bilateral asymmetrical amyotrophy of the hand and forearm muscles in C8-T1 distribution. Magnetic resonance imaging (MRI) is the best technique for the evaluation and imaging of this entity. This is a retrospective review of cervical magnetic resonance images of patients that were taken for clinically suspected and diagnosed HD on 3T MRI in postcontrast neutral and flexion (30°-40°) positions from July 2019 to January 2024 at Shri Ram Murti Smarak Institute of Medical Sciences, Bareilly. Fourteen patients included in the study were males less than 34 years of age. MRI findings of cord atrophy in the lower cervical region/cervico-dorsal junction, abnormal cervical curvature, loss of attachment of the dorsal dural sac and subjacent laminae with anterior displacement, and a prominent intense enhancing posterior epidural space were observed in all 14 patients. The minimum anteroposterior cord diameters in the neutral and flexion positions were 2.9 and 2.8 mm, respectively (mean thickness of laminodural space on flexion - 5.2 mm). Other MRI findings showed variable representations. Flexion-position MRI has emerged as the gold standard for establishing and validating the diagnosis of HD in clinically suspected cases and should be an essential part of the protocol for the screening of clinically suspected cases of HD to aid in early treatment and therapeutic intervention. Complimentary newer sequences such as the Three-dimensional (3D)-Constructive interference in Steady State (CISS)/Fast Imaging Employing Steady-state Acquisition Cycled Phases (FIESTA-C) may reinforce better appreciation of epidural flow voids.

Association of nutritional intake with clinical and imaging activity in pediatric multiple sclerosis

Background: Understanding nutrition’s role in multiple sclerosis (MS) can guide recommendations and intervention-based studies. Objective: Evaluate the association between nutrition and pediatric-onset MS outcomes. Methods: Prospective longitudinal multicenter study conducted as part of the US Network of Pediatric MS centers. Predictors were collected using a food screener estimating intake of various dietary food groups (e.g. dairy and fruits) and additional calculated indices (e.g. Healthy Eating Index (HEI)). Outcomes included time-from-enrollment to clinical relapse, new magnetic resonance imaging (MRI) T2 lesions, and Expanded Disability Status Scale (EDSS) increase. Results: 353 children with MS were enrolled (mean ± SD age 15.4 ± 2.9, follow-up 3.9 ± 2.6 years). Multivariable analysis demonstrated that increased dairy by 50% of recommended intake was associated with increased relapse risk by 41% (adjusted hazard ratio (HR) 1.41, 95% CI 1.07–1.86), and risk of T2 progression by 40% (1.40, 1.12–1.74). Increased intake of fruit or vegetable above recommended, and every five-point HEI increase decreased relapse risk by 25% (0.75, 0.60–0.95), 45% (0.55, 0.32–0.96), and 15% (0.84, 0.74–0.96), respectively. No associations were found with EDSS. Conclusion: This work supports the influence of dietary intake on MS course, particularly with dairy intake. Future prospective study is required to establish causation.

A Reproducible Pipeline for Parcellation of the Anterior Limb of the Internal Capsule

BackgroundThe anterior limb of the internal capsule (ALIC) is a white matter structure that connects the prefrontal cortex (PFC) to the brainstem, thalamus, and subthalamic nucleus. It is a target for deep brain stimulation for obsessive-compulsive disorder. There is strong interest in improving deep brain stimulation targeting by using diffusion tractography to reconstruct and target specific ALIC fiber pathways, but this methodology is susceptible to errors and lacks validation. To address these limitations, we developed a novel diffusion tractography pipeline that generates reliable and biologically validated ALIC white matter reconstructions. MethodsFollowing algorithm development and refinement, we analyzed 43 control participants, each with 2 sets of 3T magnetic resonance imaging data and a subset of 5 control participants with 7T data from the Human Connectome Project. We generated 22 segmented ALIC fiber bundles (11 per hemisphere) based on PFC regions of interest, and we analyzed the relationships among bundles. ResultsWe successfully reproduced the topographies established by previous anatomical work using images acquired at both 3T and 7T. Quantitative assessment demonstrated significantly smaller intraparticipant variability than interparticipant variability for both test and retest groups across all but one PFC region. We examined the overlap between fibers from different PFC regions and a response tract for obsessive-compulsive disorder deep brain stimulation, and we reconstructed the PFC hyperdirect pathway using a modified version of our pipeline. ConclusionsOur diffusion magnetic resonance imaging algorithm reliably generates biologically validated ALIC white matter reconstructions, thereby allowing for more precise modeling of fibers for neuromodulation therapies.

Central Vein Sign and Paramagnetic Rim Lesions: Susceptibility Changes in Brain Tissues and Their Implications for the Study of Multiple Sclerosis Pathology.

Multiple sclerosis (MS) is the most common acquired inflammatory and demyelinating disease in adults. The conventional diagnostic of MS and the follow-up of inflammatory activity is based on the detection of hyperintense foci in T2 and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) and lesions with brain-blood barrier (BBB) disruption in the central nervous system (CNS) parenchyma. However, T2/FLAIR hyperintense lesions are not specific to MS and the MS pathology and inflammatory processes go far beyond focal lesions and can be independent of BBB disruption. MRI techniques based on the magnetic susceptibility properties of the tissue, such as T2*, susceptibility-weighted images (SWI), and quantitative susceptibility mapping (QSM) offer tools for advanced MS diagnostic, follow-up, and the assessment of more detailed features of MS dynamic pathology. Susceptibility-weighted techniques are sensitive to the paramagnetic components of biological tissues, such as deoxyhemoglobin. This capability enables the visualization of brain parenchymal veins. Consequently, it presents an opportunity to identify veins within the core of multiple sclerosis (MS) lesions, thereby affirming their venocentric characteristics. This advancement significantly enhances the accuracy of the differential diagnostic process. Another important paramagnetic component in biological tissues is iron. In MS, the dynamic trafficking of iron between different cells, such as oligodendrocytes, astrocytes, and microglia, enables the study of different stages of demyelination and remyelination. Furthermore, the accumulation of iron in activated microglia serves as an indicator of latent inflammatory activity in chronic MS lesions, termed paramagnetic rim lesions (PRLs). PRLs have been correlated with disease progression and degenerative processes, underscoring their significance in MS pathology. This review will elucidate the underlying physical principles of magnetic susceptibility and their implications for the formation and interpretation of T2*, SWI, and QSM sequences. Additionally, it will explore their applications in multiple sclerosis (MS), particularly in detecting the central vein sign (CVS) and PRLs, and assessing iron metabolism. Furthermore, the review will discuss their role in advancing early and precise MS diagnosis and prognostic evaluation, as well as their utility in studying chronic active inflammation and degenerative processes.

Magnetic resonance imaging T1 mapping of the liver, pancreas and spleen in children

PurposeTo characterize T1 relaxation times of the pancreas, liver, and spleen in children with and without abdominal pathology.MethodsThis retrospective study included pediatric patients (< 18-years-old). T1 mapping was performed with a Modified Look-Locker Inversion Recovery sequence. Patients were grouped based on review of imaging reports and electronic medical records. The Kruskal–Wallis test with Dunn’s multiple comparison was used to compare groups.Results220 participants were included (mean age: 11.4 ± 4.2 years (1.5 T); 10.9 ± 4.5 years (3 T)). Pancreas T1 (msec) was significantly different between subgroups at 1.5 T (p < 0.0001). Significant pairwise differences included: normal (median: 583; IQR: 561–654) vs. acute pancreatitis (731; 632–945; p = 0.0024), normal vs. chronic pancreatitis (700; 643–863; p = 0.0013), and normal vs. acute + chronic pancreatitis (1020; 897–1099; p < 0.0001). Pancreas T1 was also significantly different between subgroups at 3 T (p < 0.0001). Significant pairwise differences included: normal (779; 753–851) vs. acute pancreatitis (1087; 910–1259; p = 0.0012), and normal vs. acute + chronic pancreatitis (1226; 1025–1367; p < 0.0001).Liver T1 was significantly different between subgroups only at 3 T (p = 0.0011) with pairwise differences between normal (818, 788–819) vs. steatotic (959; 848–997; p = 0.0017) and normal vs. other liver disease (882; 831–904; p = 0.0455). Liver T1 was weakly correlated with liver fat fraction at 1.5 T (r = 0.39; 0.24–0.52; p < 0.0001) and moderately correlated at 3 T (r = 0.64; 0.49–0.76; p < 0.0001).There were no significant differences in splenic T1 relaxation times between subgroups.ConclusionPancreas T1 relaxation times are higher at 1.5 T and 3 T in children with pancreatitis and liver T1 relaxation times are higher in children with steatotic and non-steatotic chronic liver disease at 3 T.

Comparison of Continuous Intracortical and Scalp Electroencephalography in Comatose Patients with Acute Brain Injury.

Depth electroencephalography (dEEG) is a recent invasive monitoring technique used in patients with acute brain injury. This study aimed to describe in detail the clinical manifestations of nonconvulsive seizures (NCSzs) with and without a surface EEG correlate, analyze their long-standing effects, and provide data that contribute to understanding the significance of certain scalp EEG patterns observed in critically ill patients. We prospectively enrolled a cohort of 33 adults with severe acute brain injury admitted to the neurological intensive care unit. All of them underwent multimodal invasive monitoring, including dEEG. All patients were scanned on a 3T magnetic resonance imaging scanner at 6months after hospital discharge, and mesial temporal atrophy (MTA) was calculated using a visual scale. In 21 (65.6%) of 32 study participants, highly epileptiform intracortical patterns were observed. A total of 11 (34.3%) patients had electrographic or electroclinical seizures in the dEEG, of whom 8 had both spontaneous and stimulus-induced (SI) seizures, and 3 patients had only spontaneous intracortical seizures. An unequivocal ictal scalp correlate was observed in only 3 (27.2%) of the 11 study participants. SI-NCSzs occurred during nursing care, medical procedures, and family visits. Subtle clinical manifestations, such as restlessness, purposeless stereotyped movements of the upper limbs, ventilation disturbances, jerks, head movements, hyperextension posturing, chewing, and oroalimentary automatisms, occurred during intracortical electroclinical seizures. MTA was detected in 18 (81.8%) of the 22 patients. There were no statistically significant differences between patients with MTA with and without seizures or status epilepticus. Most NCSzs in critically ill comatose patients remain undetectable on scalp EEG. SI-NCSzs frequently occur during nursing care, medical procedures, and family visits. Semiology of NCSzs included ictal minor signs and subtle symptoms, such as breathing pattern changes manifested as patient-ventilator dyssynchrony.

Brain and cervical spinal cord MRI correlates of sensorimotor impairment in patients with multiple sclerosis.

Cervical spinal cord (cSC) lesions and atrophy contribute to disability in multiple sclerosis (MS), but associations with specific sensorimotor dysfunction require further exploration. To investigate the associations of brain and cSC magnetic resonance imaging (MRI) measures with sensorimotor impairment in MS. One hundred fifty-one MS patients and 69 healthy controls underwent 3T MRI and clinical assessments including Expanded Disability Status Scale (EDSS), 9-hole peg test (9-HPT), finger tapping test (FTT), timed 25-foot walk test (T25FWT), and vibration detection threshold (VDT). Random forest ranked brain (T2-hyperintense lesion volume (T2-LV) and normalized deep gray matter (GM), cortical and white matter (WM) volumes) and cSC (T2-LV and total, GM, and WM cross-sectional areas (CSAs) at C2/C3 level) MRI measures relevance in explaining EDSS milestones (EDSS ⩾3.0, ⩾4.0, and ⩾6.0), VDT, pyramidal and sensory functional systems (P-FS and S-FS ⩾2), and motor tests impairment. Various combinations of brain and cSC MRI measures explained EDSS milestones (area under the curve (AUC) =0.879-0.900), VDT (R2 = 0.194), and impaired P-FS (AUC = 0.820), S-FS (AUC = 0.795), 9-HPT (AUC = 0.793), FTT (AUC = 0.740), and T25FWT (AUC = 0.825). cSC GM CSA was the most informative feature for all outcomes, except 9-HPT. cSC MRI measures, especially GM CSA, explain EDSS and sensorimotor dysfunction better than brain measures in MS.

Iron incorporation in red blood cells of pediatric sickle cell anemia: a stable isotope pilot investigation.

Sickle cell anemia (SCA) is marked by hypoxia, inflammation, and secondary iron overload (IO), which potentially modulate hepcidin, the pivotal hormone governing iron homeostasis. The aim was to evaluate the iron incorporation in red blood cells (RBC) in SCA pediatric patients, considering the presence or absence of IO. SCA children (n = 12; SCAtotal) ingested an oral stable iron isotope (57Fe) and iron incorporation in RBC was measured after 14 days. Patients with ≥1000 ng/mL serum ferritin were considered to present IO (SCAio+; n = 4) while the others were classified as being without IO (SCAio-; n = 8). Liver iron concentration (LIC) was determined by Magnetic Resonance Imaging (MRI) T2* method. The SCAio+ group had lower iron incorporation (mean ± SD: 0.166 ± 0.04 mg; 3.33 ± 0.757%) than SCAio- patients (0.746 ± 0.303 mg; 14.9 ± 6.05%) (p = 0.024). Hepcidin was not different between groups. Iron incorporation was inversely associated with serum ferritin level (SCAtotal group: r = -0.775, p = 0.041; SCAio- group: r = -0.982; p = 0.018) and sickle hemoglobin (HbS) presented positive correlation with iron incorporation (r = 0.991; p = 0.009) in SCAio- group. LIC was positively associated with ferritin (SCAtotal: r = 0.921; p = 0.026) and C reactive protein (SCAio+: r = 0.999; p = 0.020). SCAio+ group had lower iron incorporation in RBC than SCAio- group, suggesting that they may not need to reduce their intake of iron-rich food, as usually recommended. Conversely, a high percentage of HbS may indirectly exacerbate hypoxia and seems to increase iron incorporation in RBC. This trial was registered at www.ensaiosclinicos.gov.br . Identifier RBR-4b7v8pt.

Comparison of a Whole-Brain Contrast-Enhanced 3D TSE T1WI versus Orbits Contrast-Enhanced 2D Coronal T1WI at 3T MRI for the Detection of Optic Nerve Enhancement in Patients with Acute Loss of Visual Acuity.

MR imaging is the technique of choice for patients presenting with acute loss of visual acuity with no obvious ophthalmologic cause. The goal of our study was to compare orbits contrast-enhanced 2D coronal T1WI with a whole-brain contrast-enhanced 3D (WBCE-3D) TSE T1WI at 3T for the detection of optic nerve enhancement. This institutional review board-approved retrospective single-center study included patients presenting with acute loss of vision who underwent 3T MR imaging from November 2014 to February 2020. Two radiologists, blinded to all data, individually assessed the presence of enhancement of the optic nerve on orbits contrast-enhanced 2D T1WI and WBCE-3D T1WI separately and in random order. A McNemar test and a Cohen κ method were used for comparing the 2 MR imaging sequences. One thousand twenty-three patients (638 women and 385 men; mean age, 42 [SD, 18.3] years) were included. There was a strong concordance between WBCE-3D T1WI and orbits contrast-enhanced 2D T1WI when detecting enhancement of the optic nerve: κ = 0.87 (95% CI, 0.84-0.90). WBCE-3D T1WI was significantly more likely to detect canalicular enhancement compared with orbits contrast-enhanced 2D T1WI: 178/1023 (17.4%) versus 138/1023 (13.5%) (P < .001) and 108/1023 (10.6%) versus 90/1023 (8.8%) (P = .04), respectively. The WBCE-3D T1WI sequence detected 27/1023 (3%) instances of optic disc enhancement versus 0/1023 (0%) on orbits contrast-enhanced 2D T1WI. There were significantly fewer severe artifacts on WBCE-3D T1WI compared with orbits contrast-enhanced 2D T1WI: 68/1023 (6.6%) versus 101/1023 (9.8%) (P < .001). The median reader-reported confidence was significantly higher with coronal T1WI compared with 3D TSE T1WI: 5 (95% CI, 4-5) versus 3 (95% CI, 1-4; P < .001). Our study showed that there was a strong concordance between WBCE-3D T1WI and orbits contrast-enhanced 2D T1WI when detecting enhancement of the optic nerve in patients with acute loss of visual acuity with no obvious ophthalmologic cause. WBCE-3D T1WI demonstrated higher sensitivity and specificity in diagnosing optic neuritis, particularly in cases involving the canalicular segments.

NURS-12. NEURO-RADIOLOGY 101 FOR RNS AND APPS

Abstract BACKGROUND Magnetic Resonance Imaging (MRI) brain are the gold standard of diagnosing pediatric brain tumors. In pediatrics, MRI’s are often presented at new diagnosis or recurrence at tumor boards, which includes APP and RN’s in a multidisciplinary approach. By providing basic understanding of MRI imaging and sequencing, APP’s and RN’s will be able to participate and understand patient treatment discussions. METHODS During the presentation, we will review the 3 common planes used in MRIs: axial, coronal, and sagittal. We will then discuss the common MRI sequences, including T1, T2, FLAIR, DWI, and post-contrast imaging and discuss which common brain tumors and anatomy are best seen on said sequences. RESULTS NA. CONCLUSIONS By the end of this presentation, pediatric RNs and APPs will have the basic understanding of MRI images and feel more confident to participate in multidisciplinary tumor board discussions.