Postnatal growth restriction and deficits in fat-free mass are associated with impaired neurodevelopment. The optimal body composition to support normal brain growth and development remains unclear. ...This study investigated the association between body composition and brain size in preterm infants. We included 118 infants born <28 weeks of gestation between 2017-2021, who underwent body composition (fat-free mass (FFM) and fat mass (FM)) and cerebral magnetic resonance imaging to quantify brain size (cerebral biparietal diameter (cBPD), bone biparietal diameter (bBPD), interhemispheric distance (IHD), transverse cerebellar diameter (tCD)) at term-equivalent age. FFM Z-Score significantly correlated with higher cBPD Z-Score (rs = 0.69;
< 0.001), bBPD Z-Score (rs = 0.48;
< 0.001) and tCD Z-Score (rs = 0.30;
= 0.002); FM Z-Score significantly correlated with lower brain size (cBPD Z-Score (rs = -0.32;
< 0.001) and bBPD Z-Score (rs = -0.42;
< 0.001). In contrast weight (rs = 0.08), length (rs = -0.01) and head circumference Z-Score (rs = 0.14) did not. Linear regression model adjusted for important neonatal variables revealed that FFM Z-Score was independently and significantly associated with higher cBPD Z-Score (median 0.50, 95% CI: 0.59, 0.43;
< 0.001) and bBPD Z-Score (median 0.31, 95% CI: 0.42, 0.19;
< 0.001); FM Z-Score was independently and significantly associated with lower cBPD Z-Score (median -0.27, 95% CI: -0.42, -0.11;
< 0.001) and bBPD Z-Score (median -0.32, 95% CI: -0.45, -0.18;
< 0.001). Higher FFM Z-Score and lower FM Z-scores were significantly associated with larger brain size at term-equivalent age. These results indicate that early body composition might be a useful tool to evaluate and eventually optimize brain growth and neurodevelopment.
Epilepsy surgery is the recommended treatment option for patients with drug-resistant temporal lobe epilepsy (TLE). This method offers a good chance of seizure freedom but carries a considerable risk ...of postoperative language impairment. The extremely variable neurocognitive profiles in surgical epilepsy patients cannot be fully explained by extent of resection, fiber integrity, or current task-based functional MRI (fMRI). In this study, the authors aimed to investigate pathology- and surgery-triggered language organization in TLE by using fMRI activation and network analysis as well as considering structural and neuropsychological measures.
Twenty-eight patients with unilateral TLE (16 right, 12 left) underwent T1-weighted imaging, diffusion tensor imaging, and task-based language fMRI pre- and postoperatively (n = 15 anterior temporal lobectomy, n = 11 selective amygdalohippocampectomy, n = 2 focal resection). Twenty-two healthy subjects served as the control cohort. Functional connectivity, activation maps, and laterality indices for language dominance were analyzed from fMRI data. Postoperative fractional anisotropy values of 7 major tracts were calculated. Naming, semantic, and phonematic verbal fluency scores before and after surgery were correlated with imaging parameters.
fMRI network analysis revealed widespread, bihemispheric alterations in language architecture that were not captured by activation analysis. These network changes were found preoperatively and proceeded after surgery with characteristic patterns in the left and right TLEs. Ipsilesional fronto-temporal connectivity decreased in both left and right TLE. In left TLE specifically, preoperative atypical language dominance predicted better postoperative verbal fluency and naming function. In right TLE, left frontal language dominance correlated with good semantic verbal fluency before and after surgery, and left fronto-temporal language laterality predicted good naming outcome. Ongoing seizures after surgery (Engel classes ID-IV) were associated with naming deterioration irrespective of seizure side. Functional findings were not explained by the extent of resection or integrity of major white matter tracts.
Functional connectivity analysis contributes unique insight into bihemispheric remodeling processes of language networks after epilepsy surgery, with characteristic findings in left and right TLE. Presurgical contralateral language recruitment is associated with better postsurgical language outcome in left and right TLE.
Background and Aims
Despite vaccination recommendations, hepatitis B (HBV) and D (HDV) coinfections are common in HIV+individuals.
Methods
HBV immunization status (anti‐HBs) as well as HBV ...(HBsAg/HBV‐DNA) and HDV (anti‐HDV) coinfection rates were assessed in 1870 HIV+individuals at HIV diagnosis (baseline, BL) and last follow‐up (FU).
Results
Sixty‐eight (3.6%) HIV patients were never tested for HBV. At BL, 89/1802 (4.9%) HIV patients were HBV coinfected. Four hundred and fifteen (23.0%) showed virological HBV clearance HBsAg(‐)/anti‐HBc(+)/anti‐HBs(+) and 210 (11.7%) presented with anti‐HBc(+) only. Seven hundred and ten (39.4%) were HBV naïve HBsAg(‐)/anti‐HBs(‐)/anti‐HBc(‐)/HBV‐DNA(‐), but only 378 (21.0%) received vaccinations with detectable anti‐HBs(+) titres. Among the 89 HBV/HIV‐coinfected patients, only 52 (58.4%) were tested for HDV: 11/49 (22.4%) had anti‐HDV(+) and 3/12 (25.0%) showed HDV‐RNA viraemia. During a median FU of 6.5 (IQR 7.2) years, 44 (4.6%) of the 953 retested BL HBV‐negative patients acquired new HBV infection (including 15/304, 4.9% of vaccinated patients). Of the 89 patients, 22 (24.7%) patients cleared their HBsAg, resulting in 60/1625 (3.7%) HIV/HBV individuals at FU: 34 (56.7%) showed HBV‐DNA suppression and 15 (25.0%) were HBV viraemic, while 12/89 (13.5%) remained without a FU test. Vaccinations induced anti‐HBs(+) in 137 of the retested 649 (21.1%) BL HBV‐naïve patients.
Conclusion
HBV testing is well established among Viennese HIV+patients with HBV coinfection rates around 4%‐5%. HBV vaccinations are insufficiently implemented since anti‐HBs titres were detected in only 21.1% of HBV‐naive HIV(+) patients and new HBV infections occurred in previously vaccinated patients. HDV testing is not systematically performed despite up to 25% of HIV/HBV patients may show HDV coinfection.
Impairment of cognitive functions is commonly observed in temporal lobe epilepsy (TLE). The aim of this study was to assess visuospatial memory functions and memory-related networks using an adapted ...version of Roland's Hometown Walking (RHWT) functional MRI (fMRI) task in patients with TLE.
We used fMRI to study activation patterns based on a visuospatial memory paradigm in 32 TLE patients (9 right; 23 left) and also within subgroups of lesional and non-lesional TLE. To test for performance, a correlational analysis of fMRI activation patterns and out-of-scanner neuropsychological visuospatial memory testing was performed. Additionally, we assessed memory-related networks using functional connectivity (FC).
Greater contralateral than ipsilateral mesiotemporal (parahippocampal gyrus/hippocampus) activation was observed in left (n = 23)/right (n = 9) TLE. In lesional left TLE (n = 17), significant activations were seen in right more than left mesiotemporal areas (parahippocampal gyrus), while non-lesional left TLE patients (n = 6) showed significant bilateral (left>right) activations in mesiotemporal structures (parahippocampal gyrus). In left TLE, visuospatial cognitive testing correlated with fMRI activations in left (parahippocampal gyrus) and right mesiotemporal structures (hippocampus), characterized by greater fMRI activation being associated with better memory scores. In right TLE, higher scores in visuospatial memory testing were associated with greater fMRI activations in left and right insular regions. FC patterns of memory-related networks differ in right and left TLE.
While TLE in general leads to asymmetrical mesiotemporal activation, lesion-induced and non-lesional TLE patients reveal different memory fMRI activation patterns. In right TLE, insular regions try to compensate for impaired right mesiotemporal structures during the performance of visuospatial tasks. Underlying functional visuospatial memory networks differ in right and left TLE.
Advanced MR imaging of brain tumors is still mainly based on qualitative imaging. PET imaging offers additive metabolic information, and MR fingerprinting (MRF) offers a novel approach to ...quantitative data acquisition. The purpose of this study was to evaluate the ability of MRF to predict tumor regions and grading in combination with PET.
Seventeen patients with histologically verified infiltrating gliomas and available amino-acid PET data were enrolled. ROIs for solid tumor parts (SPo), perifocal edema (ED1), and normal-appearing white matter (NAWM) were selected on conventional MRI sequences and aligned to the MRF and PET images. The predictability of gliomas by region and grading as well as intermodal correlations were assessed.
For MRF, we calculated an overall predictability by region (SPo, ED1, and NAWM) for all of the MRF parameters of 76.5%, 47.1%, and 94.1%, respectively. The overall ability to distinguish low- from high-grade gliomas using MRF was 88.9% for LGG and 75% for HGG, with an accuracy of 82.4%, a ppV of 85.71%, and an npV of 80%. PET positivity was found in 13/17 patients for solid tumor parts, and in 3/17 patients for the edema region. However, there was no significant difference in region-specific MRF values between PET positive and PET negative patients.
MRF and PET provide quantitative measurements of the tumor tissue characteristics of gliomas, with good predictability. Nonetheless, the results are dissimilar, reflecting the different underlying mechanisms of each method.
Purpose
Neonates born at < 28 weeks of gestation are at risk for neurodevelopmental delay. The aim of this study was to identify quantitative MR-based metrics for the prediction of neurodevelopmental ...outcomes in extremely preterm neonates.
Methods
T1-/T2-relaxation times (T1R/T2R), ADC, and fractional anisotropy (FA) of the left/right posterior limb of the internal capsule (PLIC) and the brainstem were determined at term-equivalent ages in a sample of extremely preterm infants (
n
= 33). Scores for cognitive, language, and motor outcomes were collected at one year corrected-age. Pearson’s correlation analyses detected relationships between quantitative measures and outcome data. Stepwise regression procedures identified imaging metrics to estimate neurodevelopmental outcomes.
Results
Cognitive outcomes correlated significantly with T2R (
r
= 0.412;
p
= 0.017) and ADC (
r
= −0.401;
p
= 0.021) (medulla oblongata). Furthermore, there were significant correlations between motor outcomes and T1R (pontine tegmentum (
r
= 0.346;
p
= 0.049), midbrain (
r
= 0.415;
p
= 0.016), right PLIC (
r
= 0.513;
p
= 0.002), and left PLIC (
r
= 0.504;
p
= 0.003)); T2R (right PLIC (
r
= 0.405;
p
= 0.019)); ADC (medulla oblongata (
r
= −0.408;
p
= 0.018) and pontine tegmentum (
r
= −0.414;
p
= 0.017)); and FA (pontine tegmentum (
r
= −0.352;
p
= 0.045)).
T2R/ADC (medulla oblongata) (cognitive outcomes (R
2
= 0.296;
p
= 0.037)) and T1R (right PLIC)/ADC (medulla oblongata) (motor outcomes (R
2
= 0.405;
p
= 0.009)) revealed predictive potential for neurodevelopmental outcomes.
Conclusion
There are relationships between relaxometry‑/DTI-based metrics determined by neuroimaging near term and neurodevelopmental outcomes collected at one year of age. Both modalities bear prognostic potential for the prediction of cognitive and motor outcomes. Thus, quantitative MRI at term-equivalent ages represents a promising approach with which to estimate neurologic development in extremely preterm infants.
Purpose
To investigate the reproducibility of radiomics features extracted from two-dimensional regions of interest (2D ROIs) versus whole lung (3D) ROIs in repeated in-vivo fetal magnetic resonance ...imaging (MRI) acquisitions.
Methods
Thirty fetal MRI scans including two axial T2-weighted acquisitions of the lungs were analysed. 2D (lung at the level of the carina) and 3D (whole lung) ROIs were manually segmented using ITK-Snap. Ninety-five radiomics features were extracted from 2 and 3D ROIs in initial and repeat acquisitions using Pyradiomics. Radiomics feature intra-class correlation coefficients (ICC) were calculated between 2 and 3D ROIs in the initial acquisition, and between 2 and 3D ROIs in repeated acquisitions, respectively.
Results
MRI data of 11 (36.7%) female and 19 (63.3%) male fetuses acquired at a median 25 + 0 gestational weeks plus days (GW) (interquartile range IQR 23 + 4 − 27 + 0 GW) were assessed. Median radiomics feature ICC between 2 and 3D ROIs in the initial MRI acquisition was 0.733 (IQR 0.313–0.814, range 0.018–0.970). ICCs between radiomics features extracted using 3D ROIs in initial and repeat acquisitions (median 0.908 IQR 0.824–0.929, range 0.335–0.996) were significantly higher compared to 2D ROIs (0.771 0.699–0.835, 0.048–0.965) (
p
< 0.001).
Conclusion
Fetal MRI radiomics features extracted from 3D whole lung segmentation masks showed significantly higher reproducibility across repeat acquisitions compared to 2D ROIs. Therefore, fetal MRI whole lung radiomics features are robust diagnostic and potentially prognostic tools in the image-based in-vivo quantitative assessment of lung development.
Key points
Standardised fetal MRI delivers reproducible quantitative whole lung radiomics features.
2D lung ROI radiomics features are not representative of the whole fetal lung.
Whole lung radiomics features are better reproducible than 2D ROI features.
Whole lung radiomics features are more sensitive to subtle differences between normal and pathological fetal lung development compared to 2D lung ROI features.
Fetal MRI whole lung radiomics may improve non-invasive in-vivo lung development assessment.
Purpose
The purpose of this study was to assess the diagnostic accuracy of T1-weighted and T2-weighted contrasts generated by the MR data postprocessing software SyMRI (Synthetic MR AB, Linköping, ...Sweden) for neonatal brain imaging.
Methods
In this study 36 cases of neonatal MRI were retrospectively collected, which included T1-weighted and T2-weighted sequences as well as multi-dynamic multi-echo (MDME) sequences. Of the 36 neonates 32 were included in this study and 4 neuroradiologists independently assessed neonatal brain examinations on the basis of conventional and SyMRI-generated T1-weighted and T2-weighted contrasts, in order to determine the presence or absence of lesions. The sensitivity and specificity of both methods were calculated and compared.
Results
Compared to conventionally acquired T1 and T2-weighted images, SyMRI-generated contrasts showed a lower sensitivity but a higher specificity (SyMRI sensitivity 0.88, confidence interval (CI): 0.72–0.95; specificity 1, CI: 0.89–1/conventional MRI: sensitivity: 0.94, CI: 0.80–0.98; specificity: 0.94, CI: 0.80–0.98).
Conclusion
The T1-weighted and T2-weighted images generated by SyMRI showed a diagnostic accuracy comparable to that of conventionally acquired contrasts. In addition to semiquantitative imaging data, SyMRI provides diagnostic images and leads to a more efficient use of available imaging time in neonatal brain MRI.
Epilepsy is frequently accompanied by severe cognitive side effects. Temporal lobe epilepsy (TLE), and even successful surgical treatment, may affect cognitive function, in particular language as ...well as verbal and visual memory function. Epilepsy arising from the temporal lobe can be controlled surgically in up to 70% of patients. The goals of epilepsy surgery are to remove the brain areas generating the seizures without causing or aggravating neuropsychological deficits. This requires accurate localization of the brain areas generating the seizures (“epileptogenic zone”) and the areas responsible for motor and cognitive functions, such as language and memory (“essential brain regions”) during presurgical evaluation. In the past decades, functional magnetic resonance imaging (fMRI) has been increasingly used to noninvasively lateralize and localize not only primary motor and somatosensory areas, but also brain areas that are involved in everyday language and memory processes. The imaging modality also shows potential for predicting the effects of temporal lobe resection on language and memory function. Together with other MRI modalities, cognitive fMRI is a promising tool to improve surgical strategies tailored to individual patients with regard to functional outcome, by virtue of definition of epileptic cerebral areas that need to be resected and eloquent areas that need to be spared.
The aim of this review is to provide an overview of recent developments and practical recommendations for the clinical use of cognitive fMRI in TLE.
To describe cerebral abnormalities and their risk factors in a contemporary cohort of infants born extremely premature after the introduction of routine cerebral magnetic resonance imaging (cMRI) at ...term-equivalent age.
All cMRI examinations performed during November 2017 and November 2020, based on a standardized neonatal cMRI protocol, were included into analysis. Pathologies were retrospectively classified into 3 categories: intraventricular hemorrhage (IVH), white matter disease, and cerebellar injuries.
A total of 198 cMRI examinations were available for analyses; 93 (47%) showed abnormalities, most frequently IVH (n = 65, 33%), followed by cerebellar injuries (n = 41, 21%), and white matter disease (n = 28, 14%). Severe abnormalities were found in 18% of patients (n = 36). Significant clinical risk factors for abnormalities on cMRI were lower Apgar scores, lower umbilical artery and first neonatal pH, asphyxia, blood culture–proven sepsis (especially late-onset), and prolonged need of respiratory support and supplemental oxygen.
After routine cMRI, without preconfirmed pathology by cranial ultrasonography, low-grade IVH, noncystic white matter disease, and cerebellar injuries were the most frequently found abnormalities. The clinical value and long-term benefit of the detection of these low-grade pathologies have yet to be confirmed.
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