White matter hyperintensity (WMH) shape has been associated with the severity of the underlying brain pathology, suggesting it is a potential neuroimaging marker of WMH impact on brain function.In... Show moreWhite matter hyperintensity (WMH) shape has been associated with the severity of the underlying brain pathology, suggesting it is a potential neuroimaging marker of WMH impact on brain function.In 563 patients with vascular disease (58 +/- 10 years), we examined the relationship between WMH volume, shape, and cognitive functioning. WMH volume and shape were automatically determined on 1.5T brain MRI data. Standardized linear regression analyses estimated the association between WMH volume and shape (concavity index, solidity, convexity, fractal dimension, and eccentricity) and memory and executive functioning, adjusted for age, sex, educational level, and reading ability.Larger WMH volumes were associated with lower executive functioning Z-scores ( b (95%-CI):-0.09 (-0.17;-0.01)). Increased shape complexity of periventricular/confluent WMH associated with lower exec-utive functioning (concavity index + 1SD:-0.13 (-0.20;-0.06); solidity-1SD:-0.09 (-0.17;-0.02)) and lower memory function (fractal dimension + 1SD:-0.10 (-0.18;-0.02)). Of note, the association between concav-ity index and executive functioning was independent of WMH volume (-0.12 (-0.19;-0.04)). Our results suggest that WMH shape contains additional information about WMH burden, not other-wise captured by WMH volume.(c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) Show less
Roemer, F.W.; Jansen, M.; Marijnissen, A.C.A.; Guermazi, A.; Heiss, R.; Maschek, S.; ... ; Wirth, W. 2022
Background: The IMI-APPROACH cohort is an exploratory, 5-centre, 2-year prospective follow-up study of knee osteoarthritis (OA). Aim was to describe baseline multi-tissue semiquantitative MRI... Show moreBackground: The IMI-APPROACH cohort is an exploratory, 5-centre, 2-year prospective follow-up study of knee osteoarthritis (OA). Aim was to describe baseline multi-tissue semiquantitative MRI evaluation of index knees and to describe change for different MRI features based on number of subregion-approaches and change in maximum grades over a 24-month period.Methods: MRIs were acquired using 1.5 T or 3 T MRI systems and assessed using the semi-quantitative MRI OA Knee Scoring (MOAKS) system. MRIs were read at baseline and 24-months for cartilage damage, bone marrow lesions (BML), osteophytes, meniscal damage and extrusion, and Hoffa- and effusion-synovitis. In descriptive fashion, the frequencies of MRI features at baseline and change in these imaging biomarkers over time are presented for the entire sample in a subregional and maximum score approach for most features. Differences between knees without and with structural radiographic (R) OA are analyzed in addition.Results: Two hundred eighty-nine participants had readable baseline MRI examinations. Mean age was 66.6 +/- 7.1 years and participants had a mean BMI of 28.1 +/- 5.3 kg/m(2). The majority (55.3%) of included knees had radiographic OA. Any change in total cartilage MOAKS score was observed in 53.1% considering full-grade changes only, and in 73.9% including full-grade and within-grade changes. Any medial cartilage progression was seen in 23.9% and any lateral progression on 22.1%. While for the medial and lateral compartments numbers of subregions with improvement and worsening of BMLs were very similar, for the PFJ more improvement was observed compared to worsening (15.5% vs. 9.0%). Including within grade changes, the number of knees showing BML worsening increased from 42.2% to 55.6%. While for some features 24-months change was rare, frequency of change was much more common in knees with vs. without ROA (e.g. worsening of total MOAKS score cartilage in 68.4% of ROA knees vs. 36.7% of no-ROA knees, and 60.7% vs. 21.8% for an increase in maximum BML score per knee).Conclusions: A wide range of MRI-detected structural pathologies was present in the IMI-APPROACH cohort. Baseline prevalence and change of features was substantially more common in the ROA subgroup compared to the knees without ROA. Show less
Setroikromo, S.N.W.; Werff, S.J.A. van der; Smit, A.S.; Vermetten, E.; Wee, N.J.A. van der 2022
BackgroundInsights into the neurobiological basis of resilience can have important implications for the prevention and treatment of stress-related disorders, especially in populations that are... Show moreBackgroundInsights into the neurobiological basis of resilience can have important implications for the prevention and treatment of stress-related disorders, especially in populations that are subjected to high-stress environments. Evaluating large-scale resting-state networks (RSNs) can provide information regarding resilient specific brain function which may be useful in understanding resilience. This study aimed to explore functional connectivity patterns specific for (high) resilience in Dutch policemen after exposure to multiple work-related traumatic events. We investigated resting-state functional connectivity (RSFC) of the salience network (SN), limbic network, and the default-mode network (DMN). MethodsResting-state functional MRI scans were obtained from trauma-exposed executive personnel of the Dutch police force and non-trauma-exposed recruits from the police academy. Participants were divided into three groups: a resilient group (n = 31; trauma exposure; no psychopathology), a vulnerable group (n = 32; trauma exposure, psychopathology), and a control group (n = 19; no trauma exposure, no psychopathology). RSFC of the three networks of interest was compared between these groups, using an independent component analysis and a dual regression approach. ResultsWe found decreased resilience-specific positive RSFC of the salience network with several prefrontal regions. The DMN and limbic network RFSC did not show resilience-specific patterns. ConclusionThis study shows a differential RSFC specific for resilient police officers. This differential RSFC may be related to a greater capacity for internal-focused thought and interoceptive awareness, allowing more effective higher-order responses to stress in highly resilient individuals. Show less
Outeiral, R.R.; Bos, P.; Hulst, H.J. van der; Al-Mamgani, A.; Jasperse, B.; Simoes, R.; Heide, U.A. van der 2022
Background and purpose: Contouring oropharyngeal primary tumors in radiotherapy is currently done manually which is time-consuming. Autocontouring techniques based on deep learning methods are a... Show moreBackground and purpose: Contouring oropharyngeal primary tumors in radiotherapy is currently done manually which is time-consuming. Autocontouring techniques based on deep learning methods are a desirable alternative, but these methods can render suboptimal results when the structure to segment is considerably smaller than the rest of the image. The purpose of this work was to investigate different strategies to tackle the class imbalance problem in this tumor site.Materials and methods: A cohort of 230 oropharyngeal cancer patients treated between 2010 and 2018 was retrospectively collected. The following magnetic resonance imaging (MRI) sequences were available: T1 -weighted, T2-weighted, 3D T1-weighted after gadolinium injection. Two strategies to tackle the class imbal-ance problem were studied: training with different loss functions (namely: Dice loss, Generalized Dice loss, Focal Tversky loss and Unified Focal loss) and implementing a two-stage approach (i.e. splitting the task in detection and segmentation). Segmentation performance was measured with Sorensen-Dice coefficient (Dice), 95th Hausdorff distance (HD) and Mean Surface Distance (MSD). Results: The network trained with the Generalized Dice Loss yielded a median Dice of 0.54, median 95th HD of 10.6 mm and median MSD of 2.4 mm but no significant differences were observed among the different loss functions (p-value > 0.7). The two-stage approach resulted in a median Dice of 0.64, median HD of 8.7 mm and median MSD of 2.1 mm, significantly outperforming the end-to-end 3D U-Net (p-value < 0.05).Conclusion: No significant differences were observed when training with different loss functions. The two-stage approach outperformed the end-to-end 3D U-Net. Show less
Background: Histotype specific neoadjuvant therapy response data is scarce in soft tissue sarcomas. This study aimed to assess the impact of a moderate radiotherapy (RT) dose on resectability and... Show moreBackground: Histotype specific neoadjuvant therapy response data is scarce in soft tissue sarcomas. This study aimed to assess the impact of a moderate radiotherapy (RT) dose on resectability and to correlate MRI parameters to pathological treatment response in Myxoid Liposarcoma (MLS).Methods: This prospective, multicenter, single-arm, phase 2 trial assessed the radiological effects of 36 Gy of preoperative radiotherapy in primary non-metastatic MLS (n=34). Distance of the tumor to the neurovascular bundle, tumor dimensions, fat fraction, enhancing fraction were determined on MRI scans at baseline, after 8 and 16 fractions, and preoperatively. Pathological response was established by central pathology review.Results: Preoperative radiotherapy resulted in a median increase of 2 mm (IQR 0 to 6) of the distance of the tumor to the neurovascular bundle. As compared to baseline, the median change of the tumor volume, craniocaudal diameter and axial diameter at preoperative MRI were -60% (IQR -74 to -41), -19% (IQR -23 to -7) and -20% (IQR -29 to -12), respectively. The median fat fraction of 0.1 (IQR 0.0-0.1) and enhancing fraction of 0.8 (IQR 0.6 to 0.9) at baseline, changed to 0.2 (IQR 0.1 to 0.5) and to 0.5(IQR 0.4 to 0.9) preoperatively, respectively. Radiological signs of response in terms of volume, enhancing fraction and fat fraction were correlated with specific pathological signs of response like hyalinization, necrosis and fatty maturation.Conclusions: A moderate dose of preoperative radiotherapy may improve resectability in MLS and could facilitate achievement of clear margins and function preservation. MRI features which were predictive for expressions of pathological response, can play a role in further personalization of neoadjuvant treatment strategies in order to improve outcome in MLS. (C) 2021 Elsevier Ltd, BASO - The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved. Show less
Rogier, C.; Wouters, F.; Boheemen, L. van; Schaardenburg, D. van; Jong, P.H.P. de; Helm-van Mil, A.H.M. van der 2021
Objectives According to guidelines, clinical arthritis is mandatory for diagnosing RA. However, in the absence of clinical synovitis, imaging-detected subclinical synovitis is increasingly used... Show moreObjectives According to guidelines, clinical arthritis is mandatory for diagnosing RA. However, in the absence of clinical synovitis, imaging-detected subclinical synovitis is increasingly used instead and is considered as a starting point for DMARD therapy. To search for evidence we studied the natural course of arthralgia patients with subclinical synovitis from three longitudinal cohorts and determined the frequencies of non-progression to clinically apparent inflammatory arthritis (IA) (i.e. 'false positives'). Methods Subclinical synovitis in the hands or feet of arthralgia patients was visualized with US (two cohorts; definition: greyscale >= 2 and/or power Doppler >= 1) or MRI (one cohort; definition: synovitis score >= 1 by two readers). Patients were followed for 1 year on for IA development; two cohorts also had 3 year data. Analyses were stratified for ACPA. Results Subclinical synovitis at presentation was present in 36%, 41% and 31% in the three cohorts. Of the ACPA-positive arthralgia patients with subclinical synovitis, 54%, 44% and 68%, respectively, did not develop IA. These percentages were even higher in the ACPA-negative arthralgia patients: 66%, 85% and 89%, respectively. Similar results were seen after 3 years of follow-up. Conclusion Replacing clinical arthritis with subclinical synovitis to identify RA introduces a high false-positive rate (44-89%). These data suggest an overestimation regarding the value of ACPA positivity in combination with the presence of subclinical synovitis in patients with arthralgia, which harbours the risk of overtreatment if DMARDs are initiated in the absence of clinical arthritis. Show less
Objectives: To compare reliabilities of assessing synovitis in hand osteoarthritis (OA) using Magnetic Resonance Imaging (MRI) with/without gadolinium (Gd). Methods: Three readers scored synovitis... Show moreObjectives: To compare reliabilities of assessing synovitis in hand osteoarthritis (OA) using Magnetic Resonance Imaging (MRI) with/without gadolinium (Gd). Methods: Three readers scored synovitis on non-enhanced two-dimensional (2D) proton density (PD)weighted MRI and Gd-enhanced (3D) MRI of hand joints in 20 patients. Inter-reader reliabilities were examined. Results: Reliability was good for Gd-enhanced MRI, but poor for non-enhanced PD-weighted MRI (intraclass correlation coefficient 0.83 and 0.21, respectively). Agreement between the two sequences was poor (weighted kappa 0.18). Conclusion: Gd-enhanced MRI was more reliable than PD-weighted MRI for assessing synovitis. Gd-enhancement, but also resolution and tissue contrast, might have contributed to this. (c) 2021 Elsevier Inc. All rights reserved. Show less
The purpose of this study was to directly assess (patho)physiology of intraventricular hemodynamic interplay between fourdimensional flow cardiovascular magnetic resonance imaging (4D Flow MRI)... Show moreThe purpose of this study was to directly assess (patho)physiology of intraventricular hemodynamic interplay between fourdimensional flow cardiovascular magnetic resonance imaging (4D Flow MRI)-derived vorticity with kinetic energy (KE) and viscous energy loss (EL) over the cardiac cycle and their association to ejection fraction (EF) and stroke volume (SV). Fifteen healthy subjects and thirty Fontan patients underwent whole heart 4D Flow MRI. Ventricular vorticity, KE, and EL were computed over systole (vorticity_volavg systole, KEavg systole, and ELavg systole) and diastole (vorticity_volavg diastole, KEavg diastole, and ELavg diastole). The association between vorticity_vol and KE and EL was tested by Spearman correlation. Fontan patients were grouped to normal and impaired EF groups. A significant correlation was found between SV and vorticity in healthy subjects (systolic: r = 0.84, P < 0.001; diastolic: r = 0.81, P < 0.001) and in Fontan patients (systolic: r = 0.61, P < 0.001; diastolic: r = 0.54, P = 0.002). Healthy subjects showed positive correlation between vorticity_vol versus KE (systole: r = 0.96, P < 0.001; diastole: r = 0.90, P < 0.001) and EL (systole: r = 0.85, P < 0.001; diastole: r = 0.84, P < 0.001). Fontan patients showed significantly elevated vorticity_vol compared with healthy subjects (vorticity_volavg systole: 3.1 [2.3-3.9] vs. 1.7 [1.3-2.4] L/s, P < 0.001; vorticity_volavg diastole: 3.1 [2.03.7] vs. 2.1 [1.6-2.8] L/s, P = 0.002). This elevated vorticity in Fontan patients showed strong association with KE (systole: r = 0.91, P < 0.001; diastole: r = 0.85, P < 0.001) and EL (systole: r = 0.82, P < 0.001; diastole: r = 0.89, P < 0.001). Fontan patients with normal EF showed significantly higher vorticity_volavg systole and ELavg systole, but significantly decreased KE avg diastole, in the presence of normal SV, compared with healthy subjects. Healthy subjects show strong physiological hemodynamic interplay between vorticity with KE and EL. Fontan patients demonstrate a pathophysiological hemodynamic interplay characterized by correlation of elevated vorticity with KE and EL in the presence of maintained normal stroke volume. Altered vorticity and energetic hemodynamics are found in the presence of normal EF in Fontan patients.NEW & NOTEWORTHY Physiologic intraventricular hemodynamic interplay/coupling is present in the healthy left ventricle between vorticity versus viscous energy loss and kinetic energy from four-dimensional flow cardiovascular magnetic resonance imaging (4D Flow MRI). Conversely, Fontan patients present compensatory pathophysiologic hemodynamic coupling by an increase in intraventricular vorticity that positively correlates to viscous energy loss and kinetic energy levels in the presence of maintained normal stroke volume. Altered vorticity and energetics are found in the presence of normal ejection fraction in Fontan patients. Show less
Purpose Non-Cartesian imaging sequences involve sampling during rapid variation of the encoding field gradients. The quality of the reconstructed images often suffers from insufficient knowledge of... Show morePurpose Non-Cartesian imaging sequences involve sampling during rapid variation of the encoding field gradients. The quality of the reconstructed images often suffers from insufficient knowledge of the exact dynamics of the actual fields applied during sampling.Methods We propose determination of the accurate field dynamics by measuring the currents at the gradient amplifier outputs using the amplifiers' internal sensors concurrently with imaging. The actual dynamic field evolution is then determined by convolution with the measured current-to-field impulse response function of the gradient coil. Integration of the gradient field evolution allows derivation of the k-space trajectory for reconstruction.Results The current-based approach is investigated in spiral and ultrashort TE phantom imaging. In comparison with the model-based product reconstruction as well as a correction approach based on the conventional input waveform-to-field impulse response function, it provides slightly improved image quality. The improvement is ascribed to a better representation of eddy current and amplifier nonlinearity effects.Conclusion Trajectory calculation based on measured amplifier output currents offers a robust, purely measurement-based alternative to conventional model-based approaches. The implementation can mitigate gradient amplifier imperfections with no or little additional hardware effort. Show less
Christensen, C.E.; Younis, S.; Lindberg, U.; Koning, P. de; Tolnai, D.; Paulson, O.B.; ... ; Ashina, M. 2021
The middle meningeal artery is a proposed surrogate marker for activation of trigeminal nociceptors during migraine. Previous studies focused on the extracranial part of the artery; hence,... Show moreThe middle meningeal artery is a proposed surrogate marker for activation of trigeminal nociceptors during migraine. Previous studies focused on the extracranial part of the artery; hence, vasoreactivity in the intradural arteries during migraine is unknown. Thirty-four patients with migraine without aura were given sildenafil on one day and calcitonin gene-related peptide on another in double-blind crossover fashion. Patients were scanned with 3.0 T MR angiography before drug administration and again 6 hours later during induced attacks of migraine. We measured circumference of the intradural segment of the middle meningeal artery before and during induced migraine attacks. The middle cerebral and superficial temporal arteries were also examined. Fourteen patients had attacks during the second scan after both study drugs and 11 had a migraine after either one or the other, resulting in a total of 39 attacks included in the final analysis. Mean circumference of the intradural middle meningeal artery at baseline was 3.18 mm with an increase of 0.11 mm during attacks (P = 0.005), corresponding to a relative dilation of 3.6% [95% CI: 1.4%-5.7%]. Middle cerebral artery dilated by 9.4% [95% CI: 7.1%-11.7%] and superficial temporal artery by 2.3% [95% CI: 0.2%-4.4%]. Our study shows that the intradural middle meningeal artery and the middle cerebral artery are dilated during migraine induced by calcitonin gene-related peptide as well as sildenafil. We propose that intradural vasculature is affected by migraine-driven activation of trigeminal afferents during migraine attacks. Show less
Alegria, G.C.; Voirin-Hertz, M.; Garrigues, F.; Herbette, M.; Deloire, L.; Simon, A.; ... ; Saraux, A. 2020
Objective. Lumbosacral transitional vertebras (LSTVs) are common in the general population, but their potential impact on the sacroiliac joints is unclear. We aimed to determine the prevalence of... Show moreObjective. Lumbosacral transitional vertebras (LSTVs) are common in the general population, but their potential impact on the sacroiliac joints is unclear. We aimed to determine the prevalence of LSTVs and to assess their associations with sacroiliitis by standard radiography and MRI in a population with suspected axial spondyloarthritis.Methods. The data were from the DESIR cohort of 688 patients aged 18-50 years with inflammatory low back pain for 3 months but <3 years suggesting axial spondyloarthritis. The baseline pelvic radiographs were read by two blinded readers for the presence and type (Castellvi classification) of LSTVs. Associations between LSTVs and other variables collected at baseline and at the diagnosis were assessed using the chi(2) test (or Fisher's exact test) or the Mann-Whitney test.Results. LSTV was found in 200/688 (29.1%) patients. Castellvi type was Ia in 54 (7.8%), Ib in 76 (11.0%), IIa in 20 (2.9%), IIb in 12 (1.7%), IIIa in 7 (1.0%), IIIb in 21 (3.0%) and IV in 10 (1.4%) patients. Compared with the group without LSTVs, the group with LSTVs had higher proportions of patients meeting modified New York criteria for radiographic sacroiliitis (19% vs 27%, respectively; P = 0.013) and Assessment of SpondyloArthritis international Society MRI criteria for sacroiliitis (29% vs 39%, respectively; P = 0.019).Conclusion. In patients with inflammatory back pain suggesting axial spondyloarthritis, LSTVs are associated with both radiographic and MRI sacroiliitis. Show less
Background and aim: External beam radiotherapy (EBRT) combined with brachytherapy has an essential role in the curative treatment of primary vaginal cancer. EBRT is associated with significant... Show moreBackground and aim: External beam radiotherapy (EBRT) combined with brachytherapy has an essential role in the curative treatment of primary vaginal cancer. EBRT is associated with significant tumour shrinkage, making primary vaginal cancer suitable for image guided adaptive brachytherapy (IGABT). The aim of these recommendations is to introduce an adaptive target volume concept for IGABT of primary vaginal cancer.Methods: In December 2013, a task group was initiated within GYN GEC-ESTRO with the purpose to introduce an IGABT target concept for primary vaginal cancer. All participants have broad experience in IGABT and vaginal cancer brachytherapy. The target concept was elaborated as consensus agreement based on an iterative process including target delineation and dose planning comparison, retrospective analysis of clinical data and expert opinions.Results: Gynaecological examination and MR imaging are the modalities of choice for local tumour assessment. A specific template for standardised documentation with clinical drawings for vaginal cancer was developed. The adaptive target volume concept comprises different response-related target volumes. For EBRT these are related to the primary tumour and the lymph nodes, while for IGABT these are related to the primary tumour and are consisting of the residual gross tumour volume (GTV-Tres) and the high-, and intermediate risk clinical target volumes (CTV-THR, CTV-TIR).Conclusion: This target concept for IGABT of primary vaginal cancer defines adaptive target volumes for volumetric dose prescription and should improve comparability of different radiotherapy schedules of this rare disease. A prospective evaluation of the target volume concept within a multicentre study is planned. (C) 2019 Elsevier B.V. All rights reserved. Show less
Hopmans, E.M.; Heide, A. van der; Chung, P.K.; Brinkman, D.; Feltkamp, M.C.W.; Dijk, J.G. van; ... ; Niks, E.H. 2020
Rotavirus has been associated with neonatal seizures and specific white matter magnetic resonance imaging (MRI) abnormalities. We describe monochorionic twins who not only tested positive for... Show moreRotavirus has been associated with neonatal seizures and specific white matter magnetic resonance imaging (MRI) abnormalities. We describe monochorionic twins who not only tested positive for rotavirus with these white matter MRI abnormalities but who also showed an electroencephalogram (EEG) pattern characteristic of early infantile epileptic encephalopathy (EIEE), which has so far solely been described in epileptic encephalopathies with a poor prognosis. This report suggests that rotavirus infection must be added to the list of causes of EIEE EEG, and that the outcome then is likely more favorable. As MRI and EEG signs of rotavirus encephalopathy were present in one twin with only subtle neurologic symptoms, rotavirus may well cause insidious central nervous system complications more often. We suggest considering rotavirus infection in neonates presenting with seizures, and to add rotavirus infection to the differential diagnosis of EIEE. Show less
Jonkman, L.E.; Galis-de Graaf, Y.; Bulk, M.; Kaaij, E.; Pouwels, P.J.W.; Barkhof, F.; ... ; Berg, W.D.J. van de 2019
Magnetic resonance electrical properties tomography (MR-EPT) is a technique used to estimate the conductivity and permittivity of tissues from MR measurements of the transmit magnetic field.... Show moreMagnetic resonance electrical properties tomography (MR-EPT) is a technique used to estimate the conductivity and permittivity of tissues from MR measurements of the transmit magnetic field. Different reconstruction methods are available; however, all these methods present several limitations, which hamper the clinical applicability. Standard Helmholtz-based MR-EPT methods are severely affected by noise. Iterative reconstruction methods such as contrast source inversion electrical properties tomography (CSI-EPT) are typically time-consuming and are dependent on their initialization. Deep learning (DL) based methods require a large amount of training data before sufficient generalization can be achieved. Here, we investigate the benefits achievable using a hybrid approach, that is, using MR-EPT or DL-EPT as initialization guesses for standard 3D CSI-EPT. Using realistic electromagnetic simulations at 3 and 7 T, the accuracy and precision of hybrid CSI reconstructions are compared with those of standard 3D CSI-EPT reconstructions. Our results indicate that a hybrid method consisting of an initial DL-EPT reconstruction followed by a 3D CSI-EPT reconstruction would be beneficial. DL-EPT combined with standard 3D CSI-EPT exploits the power of data-driven DL-based EPT reconstructions, while the subsequent CSI-EPT facilitates a better generalization by providing data consistency. Show less
Uveal melanoma (UM), the most common primary intraocular tumour, is often complicated by exudative retinal detachment (RD). Sometimes. this exudative RD is mistaken for a rhegmatogenous detachment... Show moreUveal melanoma (UM), the most common primary intraocular tumour, is often complicated by exudative retinal detachment (RD). Sometimes. this exudative RD is mistaken for a rhegmatogenous detachment and is subsequently treated with vitrectomy with silicone oil (SiOil) tamponade. As SiOil prevents ultrasound imaging, the diagnosis, treatment planning and/or follow-up of UM underlying the detachment are often severely hindered by the SiOil. We aim to develop and evaluate new MRI methods to image UM patients with a SiOil tamponade and evaluate this in vivo. A dedicated MRI protocol for 3 and 7 T was developed and subsequently evaluated in three patients. The MRI protocol developed was evaluated in three patients. In the first patient, SiOil hindered follow-up and therefore MRI was indicated. No tumour recurrence was found after two follow-up scans. The second and third patient underwent vitrectomy with SiOil for assumed rhegmatogenous RD in another hospital, during which a mass was found. In these cases, MRI was used to determine whether the lesion was UM and perform measurements to plan brachytherapy treatment. In general, the proposed workflow is more complicated on 7 T than on 3 T as the off-resonance effects scale linearly with field strength. For example, the shimming procedure needed modifications at 7 T, whereas at 3 T, the automatic shimming sufficed. However, at 7 T, higher resolution images were obtained compared with 3 T (0.6 vs. 0.8 mm(3)). A dedicated MRI protocol enables high-resolution imaging of vitrectomized eyes with SiOil tamponade, enabling treatment planning or follow-up in UM patients. Copyright (C) 2019 The Author(s). Published by Wolters Kluwer Health, Inc. Show less
Matthijssen, X.M.E.; Wouters, F.; Boeters, D.M.; Boer, A.C.; Dakkak, Y.J.; Niemantsverdriet, E.; Helm-van Mil, A.H.M. van der 2019
Background. HIV-associated cardiovascular disease (CVD) risk in combination antiretroviral therapy (cART)-treated perinatally HIV-infected patients (PHIV+) remains unknown due to the young age of... Show moreBackground. HIV-associated cardiovascular disease (CVD) risk in combination antiretroviral therapy (cART)-treated perinatally HIV-infected patients (PHIV+) remains unknown due to the young age of this population. Lipoprotein(a) (Lp(a)) has been established as an independent causal risk factor for CVD in the general population but has not been well established in the population of PHIV+.Methods. We cross-sectionally compared lipid profiles, including nonfasting Lp(a), together with total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides between 35 cART-treated PHIV+ children aged 8-18 years and 37 controls who were matched for age, sex, ethnicity, and socioeconomic status. We explored associations between Lp(a) and disease- and treatment-related factors (inflammation, monocyte activation, and vascular), biomarkers, and neuroimaging outcomes using linear regression models.Results. PHIV+ children had significantly higher levels of Lp(a) compared with controls (median, 43.6 [21.6-82.4] vs 21.8 [16.8-46.6] mg/dL; P = .033). Other lipid levels were comparable between groups. Additional assessment of apolipoprotein B, apolipoprotein CIII, apolipoprotein E, and APOE genotype revealed no significant differences. Higher Lp(a) levels were associated with higher plasma apoB levels and with lower monocyte chemoattractant protein-1 and TG levels in PHIV+ children. Lp(a) was not associated with HIV- or cART-related variables or with neuroimaging outcomes.Conclusions. cART-treated PHIV+ children appear to have higher levels of Lp(a) compared with ethnicity-matched controls, which may implicate higher CVD risk in this population. Future research should focus on the association between Lp(a) and (sub) clinical CVD measurements in cART-treated PHIV+ patients. Show less
