Susceptibility-weighted Imaging Research Articles

Calcifications in Cerebral Infarcts: Report of Two Cases

Calcification in cerebral infarcts has been reported as an uncommon finding. CT hyperdensity in an infarct can also be due to hemorrhagic transformation and in MRI can be mimicked by cortical laminar necrosis seen as gyriform T1 hyper and T2 hypointensities. Susceptibility-weighted imaging (SWI) with phase image has been reported to differentiate calcification and hemorrhage. We report 2 cases of cerebral infarcts with a review of the literature. The first patient showed early gyriform calcification 10 days after the onset and showed partial resolution of the calcification on follow-up. The second patient showed plaque-like calcification within perisylvian infarct that was confirmed by SWI phase imaging.

Altered Brain Glymphatic Flow at Diffusion-Tensor MRI in Rapid Eye Movement Sleep Behavior Disorder.

Background Brain glymphatic dysfunction may contribute to the development of α-synucleinopathies. Yet, noninvasive imaging and quantification remain lacking. Purpose To examine glymphatic function of the brain in isolated rapid eye movement sleep behavior disorder (RBD) and its relevance to phenoconversion with use of diffusion-tensor imaging (DTI) analysis along the perivascular space (ALPS). Materials and Methods This prospective study included consecutive participants diagnosed with RBD, age- and sex-matched control participants, and participants with Parkinson disease (PD) who were enrolled and examined between May 2017 and April 2020. All study participants underwent 3.0-T brain MRI including DTI, susceptibility-weighted and susceptibility map-weighted imaging, and/or dopamine transporter imaging using iodine 123-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane SPECT at the time of participation. Phenoconversion status to α-synucleinopathies was unknown at the time of MRI. Participants were regularly followed up and monitored for any signs of α-synucleinopathies. The ALPS index reflecting glymphatic activity was calculated by a ratio of the diffusivities along the x-axis in the projection and association neural fibers to the diffusivities perpendicular to them and compared according to the groups with use of the Kruskal-Wallis and Mann-Whitney U tests. The phenoconversion risk in participants with RBD was evaluated according to the ALPS index with use of a Cox proportional hazards model. Results Twenty participants diagnosed with RBD (12 men; median age, 73 years [IQR, 66-76 years]), 20 control participants, and 20 participants with PD were included. The median ALPS index was lower in the group with RBD versus controls (1.53 vs 1.72; P = .001) but showed no evidence of a difference compared with the group with PD (1.49; P = .68). The conversion risk decreased with an increasing ALPS index (hazard ratio, 0.57 per 0.1 increase in the ALPS index [95% CI: 0.35, 0.93]; P = .03). Conclusion DTI-ALPS in RBD demonstrated a more severe reduction of glymphatic activity in individuals with phenoconversion to α-synucleinopathies. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Filippi and Balestrino in this issue.

Interobserver Agreement on Intracranial Hemorrhage on Magnetic Resonance Imaging in Patients With Ischemic Stroke.

The Heidelberg Bleeding Classification, developed for computed tomography, is also frequently used to classify intracranial hemorrhage (ICH) on magnetic resonance imaging. Additionally, the presence of any ICH is frequently used as (safety) outcome measure in clinical stroke trials that evaluate acute interventions. We assessed the interobserver agreement on the presence of any ICH and the type of ICH according to the Heidelberg Bleeding Classification on magnetic resonance imaging in patients treated with reperfusion therapy. We used 300 magnetic resonance imaging scans including susceptibility-weighted imaging or T2*-weighted gradient echo imaging of ischemic stroke patients within 1 week after reperfusion therapy. Six observers, blinded to clinical characteristics except for suspected location of the infarction, independently rated ICH according to the Heidelberg Bleeding Classification in random pairs. Percent agreement and Cohen's kappa (κ) were estimated for the presence of any ICH (yes/no), and for agreement on the Heidelberg Bleeding Classification class 1 and 2. For the Heidelberg Bleeding Classification class 1 and 2, weighted κ was estimated to take the degree of disagreement into account. In 297 of 300 scans, the quality of scans was sufficient to score ICH. Observers agreed on the presence or absence of any ICH in 264 of 297 scans (88.9%; κ 0.78 [95% CI, 0.71-0.85]). There was agreement on the Heidelberg Bleeding Classification class 1 and 2 and no ICH in class 1 and 2 in 226 of 297 scans (76.1%; κ 0.63 [95% CI, 0.56-0.69]; weighted κ 0.90 [95% CI, 0.87-0.93]). The presence of any ICH can be reliably scored on magnetic resonance imaging and can, therefore, be used as (safety) outcome measure in clinical stroke trials that evaluate acute interventions. Agreement of ICH types according to the Heidelberg Bleeding Classification is substantial and disagreements are small.

Deep cerebral venous abnormalities in premature babies with GMH-IVH: a single-centre retrospective study

PurposeGerminal matrix haemorrhage/intraventricular haemorrhage (GMH-IVH) is a multifactorial injury with both anatomic and haemodynamic involvement. Normal variants in preterm deep cerebral venous anatomy associated with GMH-IVH have been previously described...

5T magnetic resonance imaging: radio frequency hardware and initial brain imaging.

We aimed to demonstrate the feasibility of generating high-resolution human brain magnetic resonance imaging (MRI) at 5 Tesla (T) using a quadrature birdcage transmit/48-channel receiver coil assembly. A quadrature birdcage transmit/48-channel receiver coil assembly was designed for human brain imaging at 5T. The radio frequency (RF) coil assembly was validated by electromagnetic (EM) simulations and phantom imaging experimental studies. The simulated B1+ field inside a human head phantom and inside a human head model generated by the birdcage coils driven in circularly polarized (CP) mode at 3T, 5T and 7T was compared. Signal-to-noise ratio (SNR) maps, the inverse g-factor maps for evaluation of parallel imaging performance, anatomic images, angiography images, vessel wall images and susceptibility weighted images (SWI) were acquired using the RF coil assembly at 5T and compared to those acquired using a 32-channel head coil on a 3T MRI scanner. For the EM simulations, 5T MRI provided less RF inhomogeneity compared to that of 7T. In the phantom imaging study, the distributions of the measured B1+ field were consistent with the distributions of the simulated B1+ field. In the human brain imaging study, the average SNR value of the brain in the transversal plane at 5T was 1.6 times of that at 3T. The 48-channel head coil at 5T had higher parallel acceleration capability than the 32-channel head coil at 3T. The anatomic images at 5T also showed higher SNR than those at 3T. Improved delineation of the hippocampus, lenticulostriate arteries, and basilar arteries was observed at 5T compared to 3T. SWI with a higher resolution of 0.3 mm ×0.3 mm ×1.2 mm could be acquired at 5T, which enabled better visualization of small blood vessels compared to that at 3T. 5T MRI can provide significant SNR improvement compared to that of 3T with less RF inhomogeneity than that of 7T. The ability to obtain high quality in vivo human brain images at 5T using the quadrature birdcage transmit/48-channel receiver coil assembly has significant in clinical and scientific research applications.

Single Cerebral Metastasis Mimicking Pyogenic Abscess in a Patient with Lung Adenocarcinoma.

HomeRadiology: Imaging CancerVol. 5, No. 3 Images in CancerFree AccessSingle Cerebral Metastasis Mimicking Pyogenic Abscess in a Patient with Lung AdenocarcinomaVíctor Pérez-Riverola , Olalla Vázquez Muiños, Mario Prenafeta Moreno, Roser Monmany Badia, Khalid El-Hamshari Rebollo, Esther Granell MorenoVíctor Pérez-Riverola , Olalla Vázquez Muiños, Mario Prenafeta Moreno, Roser Monmany Badia, Khalid El-Hamshari Rebollo, Esther Granell MorenoAuthor AffiliationsFrom the Department of Neuroradiology, UDIAT-CD, Hospital Universitari Parc Taulí, Parc del Taulí 1, 08208 Sabadell, Spain.Address correspondence to V.P.R. (email: [email protected]).Víctor Pérez-Riverola Olalla Vázquez MuiñosMario Prenafeta MorenoRoser Monmany BadiaKhalid El-Hamshari RebolloEsther Granell MorenoPublished Online:Apr 7 2023https://doi.org/10.1148/rycan.230004MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In As clinical signs of infection are often absent in patients with pyogenic abscesses, differential diagnosis with cerebral metastases is based on MRI findings.However, both entities often manifest as ring-enhancing lesions. Pyogenic brain abscesses usually show restricted diffusion in the lesion core and the dual-rim sign at susceptibility-weighted imaging. The dual-rim sign consists of two concentric rims bordering the lesion: a complete, smooth outer hypointense rim representing the fibrocollagenous capsular wall and an inner hyperintense rim representing a zone of granulation tissue (1). At perfusion imaging, the capsule of a cerebral abscess has a lower relative cerebral blood volume than the necrotic or cystic peripheral wall of a tumor due to microvessel angiogenesis by the tumor (2).Some cerebral metastases also show restricted diffusion, which does not correlate with the histologic type of the primary cancer (3). Proposed mechanisms for restricted diffusion in metastases include intracellular edema in viable tumor cells during transition to complete liquefactive necrosis (4) and a highly viscous mucin concentration (5).Key findings that help distinguish these atypical metastases from pyogenic abscess include high peripheral wall relative cerebral blood volume and absence of the dual-rim sign (Figure).Brain MR images in a 37-year-old male patient, a heavy tobacco and cannabis smoker, after a first seizure. (A) Contrast-enhanced T1-weighted MR image shows a smooth, ring-enhancing nodular right frontal lobe lesion surrounded by abundant vasogenic edema. (B, C) On diffusion-weighted images, the central core shows restricted diffusion. (D) On susceptibility-weighted image, a hypointense smooth ring completely surrounds the lesion, simulating a capsule. (E) The relative cerebral blood volume of the lesion’s peripheral wall (arrows) is high (mean relative cerebral blood volume ratio: 7.61 ± 2.70 [SD]). Chest CT findings (not shown) detected a cavitary pulmonary mass. Tests for tuberculosis and bronchoalveolar lavage fluid analysis were negative. Chest CT findings were initially misinterpreted as an infectious process. Follow-up brain MRI 8 weeks after starting antibiotics showed enlargement of the frontal lobe lesion, new ring-enhancing cerebral and cerebellar lesions, and signs of leptomeningeal carcinomatosis in the posterior fossa. The patient was diagnosed with lung adenocarcinoma following lung lesion biopsy.Download as PowerPointOpen in Image Viewer Disclosures of conflicts of interest: V.P.R. No relevant relationships. O.V.M. No relevant relationships. M.P.M. No relevant relationships. R.M.B. No relevant relationships. K.E.H.R. No relevant relationships. E.G.M. No relevant relationships.Keywords: MRI, MR-Diffusion-weighted Imaging, MR-Perfusion, Metastasis, Neuro-oncology, Lung Adenocarcinoma, Pyogenic AbscessAuthors declared no funding for this work.

The Current State of Susceptibility-Weighted Imaging and Quantitative Susceptibility Mapping in Head Trauma.

Susceptibility-weighted imaging (SWI) is a MR imaging technique suited to detect structural and microstructural abnormalities in traumatic brain injury (TBI). This review article provide an insight in to the physics principles of SWI and its clinical application in unraveling the complex interaction of the biophysical mechanisms of head injury. Literature evidences support SWI as the most ideal sequence in detection of microbleeds, which is the "tip of the iceberg" biomarker of microvascular injuries. The review also detailed the emerging advance techniques of Quantitative susceptibility mapping (QSM) and artificial intelligence offer the ability to detect and follow the evolution of microbleeds in patient with chronic TBI. These new techniques offers a unique insight into the acute and chronic state of TBI.

Papilledema and venous stasis in patients with cerebral venous and sinus thrombosis

BackgroundCerebral venous and sinus thrombosis (CVST) can cause increased intracranial pressure, often leading to papilledema. In this study, we investigated the association between papilledema and venous stasis on susceptibility weighted imaging (SWI) in CVST.MethodsPatients with CVST between 2008 and 2020 were reviewed. Patients without fundoscopic examination or SWI were excluded in this study. Venous stasis was evaluated and scored for each cerebral hemisphere: each hemisphere was divided into 5 regions according to the venous drainage territories (superior sagittal sinus, Sylvian veins, transverse sinus and vein of Labbé, deep cerebral veins, and medullary veins) and 1 point was added if venous prominence was confirmed in one territory on SWI. The venous stasis score on SWI between cerebral hemispheres with and without papilledema was compared.ResultsEight of 19 patients with CVST were excluded because of the absence of fundoscopic examination or SWI. Eleven patients (26.5 ± 2.1 years) were included in this study. Papilledema was identified in 6 patients: bilateral papilledema in 4 patients and unilateral papilledema in 2 patients. The venous stasis score on SWI was significantly higher (P = 0.013) in the hemispheres with papilledema (median, 4.0; 95% CI, 3.038–4.562) than in the hemispheres without papilledema (median, 2.5; 95% CI, 0.695–2.805).ConclusionsThis study shows that higher score of venous stasis on SWI is associated with papilledema. Therefore, the venous stasis on SWI may be an imaging surrogate marker of increased intracranial pressure in patients with CVST.

Comparative effectiveness of dual to single antiplatelet therapy after one year versus seven years in patients with acute ischemic stroke combined with cerebral microbleeds

BackgroundCerebral microbleeds (CMBs) were thought to be associated with stroke. The relationship CMBs, antiplatelet therapy and prognosis is still unclear. Our aim here was to compare the long-term risk of stoke between dual and single antiplatelet therapies in patients of acute ischemic stroke (IS) combined with CMBs. MethodWe conducted a retrospective cohort study of 1017 acute IS patients received susceptibility weighted imaging (SWI) magnetic resonance imaging (MRI) sequences. We constructed a sample of patients received short-term dual antiplatelet therapy (DAPT) (n = 154) and received single antiplatelet therapy (SAPT) (n = 125), followed them for up to 7 years (median 33 months). DAPT was prescribed for at least 3 weeks, followed by using SAPT. The primary endpoint was a composite of all-cause death, recurrence IS or intracerebral hemorrhage (ICH). Secondary endpoints were a composite of recurrent IS or ICH, and the recurrent IS. ResultAt last follow-up, rated of the endpoints were similar in patients treated with SAPT and DAPT (P > 0.05). The IS risk was higher in patients treated with SAPT in the first year after the occurrence of acute IS (P = 0.035). And in 0–1 year or in 1–7 year, the risk of primary endpoint and main secondary endpoint were similar among patients treated with SAPT and DAPT (P > 0.05). ConclusionThe study is limited due to different baseline characteristics. We initially consider that the short-term DAPT may be considered to potentially reduce the rate of recurrent IS in the first year. In patients of IS combined with CMBs, the short-term DAPT may be recommended to reduce the recurrent IS.

Diagnostic Relevance of the Medullary Vein Sign in Neurosarcoidosis (P9-5.003)

<h3>Objective:</h3> To evaluate the diagnostic potential of the medullary vein sign as an imaging marker in neurosarcoidosis. <h3>Background:</h3> Neurosarcoidosis is a rare manifestation of sarcoidosis that can be inferred through the clinical presentation, cerebral spinal fluid (CSF) analysis, and magnetic resonance imaging (MRI) scans. However, its accurate diagnosis remains a significant challenge due to the variability in its diagnostic criteria and the overlapping clinical and imaging features with other conditions. One under-researched finding in these patients is the engorgement of the medullary vein on susceptibility-weighted imaging (SWI), termed as the ‘medullary vein sign’; postulated to be a specific sign for neurosarcoidosis, its reliability has not yet been fully elucidated. <h3>Design/Methods:</h3> A single-center retrospective study was performed between March 31st, 2022, and August 1st, 2022. Two neuroradiologists independently examined MRI images using SWI/gradient echo sequences for medullary vein engorgement. A total of 32 patients were reviewed, and the diagnosis was based on imaging, biopsy, and CSF analysis. Finally, the sensitivity and specificity of the medullary vein sign were calculated. <h3>Results:</h3> Out of 32 patients, seven were diagnosed with definitive neurosarcoidosis; the remaining were classified as possible (n=16), probable (n=5), and other (n=4) causes of infectious meningoencephalitis, including two cases of autoimmune encephalitis. Among these, the medullary vein sign was detected in seven patients: five with confirmed, and two with possible neurosarcoidosis. Overall, the sensitivity was 71.4%, and the specificity was 92.3%. CSF was largely inconclusive, and MRI was not the major diagnostic factor in most cases. <h3>Conclusions:</h3> Our findings confirm the high specificity of the medullary vein sign for neurosarcoidosis and suggest that SWI is an effective tool for early detection, especially compared to conventional MRI and CSF analysis. Incorporating this in the current diagnostic criteria may result in timely intervention, and we encourage radiologists to look for this marker in patients with suspected neurosarcoidosis. <b>Disclosure:</b> Dr. Srivastava has nothing to disclose. Dr. Sharma has nothing to disclose. Dr. Joseph has nothing to disclose. Dr. Feizi has nothing to disclose. Dr. Sriwastava has nothing to disclose.

Amygdala Grey Matter Volume and Face Activation Compared to Social Network Size

Amygdala volume and face activation activity have been linked to social network size. In the current study, these relationships were examined through analysis of Magnetic Resonance Imaging and survey data of 116 subjects, with a more detailed analysis of a smaller sub-sample of 20 subjects. Amygdalae structural volumes were analyzed using Freesurfer, functional activation was analyzed using Statistical Parametric Mapping, and ultra-high-resolution susceptibility-weighted images were analyzed using in-house MATLAB scripts. Mean amygdala volumes obtained in this experiment are in line with those reported in previous research. Left amygdala volume was correlated with social network scores in males, and both left and right hippocampus volume were correlated with the square root of the size of one’s social network in females. Significant correlations were also observed between left amygdala face activation levels and social network measures in the smaller sub-sample (n = 20).

An ultrafast brain MRI technique for evaluating acute neurologic deficits in the emergency department

Herein we share our preliminary experience with an ultrafast brain MRI technique for use in the ED consisting of axial T1-weighted (40s), axial T2-weighted (62s), axial diffusion-weighted (80s), axial FLAIR (96s), axial T2* (6s), and axial susceptibility-weighted (108s) imaging for a total scan time of 6min and 53s. Utilization of this ultrafast technique yields an efficient assessment of the brain, decreases ED length of stay and inpatient observation admissions, and may obviate the need for vascular imaging with either CTA or MRA in the ED.

A superficial siderosis-related transient focal neurological episode in a patient with Marfan syndrome.

Sagittal computed tomography of lumbal spine showing dural ectasia and Tarlow Cyst (red arrows) (A). Magnetic resonance imaging (MRI) axial slice, susceptibility-weighted imaging (SWI) sequences showing siderosis in cerebellar sulci (red arrows) and in the inset uncharacteristic iron deposition in dental nuclei, more pronounced on the left side (red arrows) (B, inset). MRI, SWI, axial slice, showing numerous foci of superficial siderosis (C).

Utility of balanced steady-state field precession sequence in the evaluation of retinal and subdural hemorrhages in patients with abusive head trauma.

Abusive head trauma is the leading cause of physical child abuse deaths in children under 5years of age in the United States. To evaluate suspected child abuse, radiologic studies are typically the first to identify hallmark findings of abusive head trauma including intracranial hemorrhage, cerebral edema, and ischemic injury. Prompt evaluation and diagnosis are necessary as findings may change rapidly. Current imaging recommendations include brain magnetic resonance imaging with the addition of a susceptibility weighted imaging (SWI) sequence which can detect additional findings that suggest abusive head trauma including cortical venous injury and retinal hemorrhages. However, SWI is limited due to blooming artifacts and artifacts from the adjacent skull vault or retroorbital fat, which can affect the evaluation of retinal, subdural, and subarachnoid hemorrhages. This work explores the utility of the high-resolution, heavily T2 weighted balanced steady-state field precession (bSSFP) sequence to identify and characterize retinal hemorrhage and cerebral cortical venous injury in children with abusive head trauma. The bSSFP sequence provides distinct anatomical images to improve the identification of retinal hemorrhage and cortical venous injury.

Teaching Neuro Images : Susceptibility-weighted MRI

A 61-year-old man with factor V Leiden thrombophilia presented with hemorrhage and transverse sinus thrombosis (figure, A). Four years later, he developed worsening aphasia, new hemorrhage, and hemispheric edema (figure, B). Susceptibility-weighted imaging (SWI) showed bright signal in the straight sinus (figure, C). A dural arteriovenous fistula (DAVF) was diagnosed (figure, D). The brain edema improved (figure, E) and SWI sinus hyperintensity resolved after endovascular disconnection of the fistula (figure, F).

Dorsolateral Nigral Hyperintensity on 1.5 T Versus 3 T Susceptibility-Weighted Magnetic Resonance Imaging in Neurodegenerative Parkinsonism.

An absent dorsolateral nigral hyperintensity (DNH) is a common finding in patients with neurodegenerative parkinsonism at high or ultra-high field susceptibility-weighted magnetic resonance imaging (SWI). Despite increasing use of high field magnetic resonance imaging (MRI) in specialized centers, these scanners are still frequently unavailable in primary care or outpatient facilities and underdeveloped or emerging countries. Therefore, the aim of the present study was to evaluate the diagnostic utility of DNH assessment at 1.5 versus 3 T MRI to distinguish patients with neurodegenerative parkinsonism, including Parkinson's disease (PD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP), from healthy controls (HC). Absence of DNH was assessed on visual inspection of anonymized 1.5 T and 3.0 T SWI scans in a case-control study including 86 patients with neurodegenerative parkinsonism and 33 healthy controls (HC). All study participants were consecutively recruited to undergo 1.5 and 3 T MRI. Overall correct classification was 81.7% (95% CI, 72.6-88.4%) for 1.5 T and 95.7% (95% CI, 89.1-98.7%) for 3 T MRI in discriminating neurodegenerative parkinsonism from controls. However, while DNH was bilaterally present in all but one of the HC at 3 T MRI, it was rated as abnormal (at least unilateral absence) in 15 of 22 HC at 1.5 T MRI, resulting in a specificity of 31.8%. The results of the present study demonstrate an insufficient specificity of visual assessment of DNH at 1.5 T MRI for the diagnosis of neurodegenerative parkinsonism.

Visualizing Cerebral Small Vessel Degeneration During Aging and Diseases Using Magnetic Resonance Imaging.

Cerebral small vessel disease is a major contributor to brain disorders in older adults. It is associated with a much higher risk of stroke and dementia. Due to a lack of clinical and fluid biomarkers, diagnosing and grading small vessel disease are highly dependent on magnetic resonance imaging. In the past, researchers mostly used brain parenchymal imaging markers to represent small vessel damage, but the relationships between these surrogate markers and small vessel pathologies are complex. Recent progress in high-resolution magnetic resonance imaging methods, including time-of-flight MR angiography, phase-contrast MR angiography, black blood vessel wall imaging, susceptibility-weighted imaging, and contrast-enhanced methods, allow for direct visualization of cerebral small vessel structures. They could be powerful tools for understanding aging-related small vessel degeneration and improving disease diagnosis and treatment. This article will review progress in these imaging techniques and their application in aging and disease studies. Some challenges and future directions are also discussed. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: 3.

Lesion-level correspondence and longitudinal properties of paramagnetic rim and slowly expanding lesions in multiple sclerosis

Background: Paramagnetic rim lesions (PRLs) and slowly expanding lesions (SELs) have been posited as markers of chronic active lesions (CALs). Objective: To assess the lesion-level concordance of PRLs and SELs in MS and to characterize changes in brain tissue integrity in CALs over time. Methods: MRIs were analyzed from a substudy of AFFINITY [NCT03222973], a phase 2 trial of opicinumab in relapsing MS. Assessments included (1) identification of SELs based on longitudinal MRIs over 72 weeks, and identification of PRLs on susceptibility-weighted imaging (SWI) filtered phase images at week 72; (2) evaluation of subject-level correlation of SEL and PRL counts, volumes, and degree of lesion-level overlap between SELs and PRLs; and (3) characterization of tissue integrity over time in overlapping and non-overlapping SELs and PRLs. Results: In 41 subjects, 119 chronic PRLs and 267 SELs were detected. Of 119 (39.5%) chronic PRLs, 47 co-localized with a SEL; 46/267 (17.2%) SELs co-localized with a PRL. PRLs co-localized with SELs showed expansion and worsening microstructural damage over time. SELs with and without co-localization with PRLs showed ongoing tissue damage. Conclusions: Chronic MS lesions identified as both PRL and SEL were associated with the most severe accumulation of tissue damage. Trial Registration: AFFINITY [NCT03222973].

Value of susceptibility-weighted imaging in differentiating benign from malignant portal vein thrombosis.

Many diseases are accompanied by portal vein thrombosis (PVT), and its nature is closely related to its prognosis and treatment. It is important to evaluate magnetic resonance imaging (MRI) parameters, including susceptibility-weighted imaging (SWI) and qualitative diffusion-weighted imaging (DWI), in the differentiation between benign and malignant PVT. In this retrospective study, we collected clinical imaging data from 140 patients with PVTs characterized as benign or malignant based on enhanced MRI between January 2011 and April 2016 and retrospectively analyzed PVTs using SWI and DWI. There were 37 benign and 103 malignant PVTs. Image review was performed by 2 radiologists blinded to clinical information. The signal intensity (SI) of PVTs was recorded on SWI. The apparent diffusion coefficient (ADC) and the ratio of signal intensity (SIR) on SWI (SIRSWI) and ADC (SIRADC) between the PVTs and the spinal cord were calculated. Finally, we generated receiver operating characteristic (ROC) curves to evaluate the efficacy of SIRSWI and SIRADC for distinguishing benign and malignant PVTs. On SWI and DWI, 100.0% (36/36) and 80.5% (29/36) of benign PVTs were hypointense, respectively. For malignant PVTs on SWI and DWI, 99.0% (103/104) and 89.4% (93/104) were hyperintense, respectively. The SIRSWI values of benign and malignant PVTs were 0.58±0.13 and 0.88±0.06, respectively, representing a significant difference (P<0.001). The SIRADC values of benign and malignant PVTs were 0.72±0.32 and 0.62±0.17, respectively, representing a significant difference (P=0.034). The area under the ROC curve (AUROC) for SIRSWI [0.990; 95% confidence interval (CI): 0.971-1.000] was significantly higher than that for SIRADC (0.619; 95% CI: 0.500-0.737; P<0.001). The SIRSWI had a sensitivity of 100.0% and a specificity of 97.3% with a cutoff value of 0.749, while the SIRADC had a sensitivity of 45.9% and specificity of 83.3% with a cutoff value of 0.791. The diagnostic performance of SWI is superior to that of DWI in the differentiation of benign and malignant PVTs.

Exploration of the correlation between superficial cerebral veins identified using susceptibility-weighted imaging findings and cognitive differences between sexes based on deep learning: a preliminary study.

This study aimed to investigate the association of superficial cerebral veins (SCVs) with sex-related cognitive differences and the possible hemodynamic mechanisms underlying these associations. This investigation was a prospective case-control study. A total of 344 healthy volunteers were recruited. In all, 200 volunteers were included to establish the deep learning model, and 144 volunteers were used for the research, including 72 males (50%) and 72 females (50%). No significant differences in age (P=0.358) or education (P=0.779) were observed between the sexes. Cognitive functioning was evaluated using neuropsychological tests, including the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment-Basic (MOCA-B). Susceptibility-weighted imaging scans were acquired with a 3.0 T magnetic resonance imaging system using a 32-channel high-resolution phased array coil. Minimum intensity projection images were obtained by reconstructing susceptibility-weighted imaging data. A deep learning model was trained on the minimum intensity projection images to quantify the diameter, tortuosity index, length, and the number of SCVs in the bilateral cerebral hemispheres. Finally, the association between cognitive differences between males and females and the properties of the SCVs was analyzed. The MMSE and MOCA-B scores of males were significantly higher than those of females (P<0.05). Males had more SCVs in the bilateral cerebral hemispheres than did females (right hemisphere: P<0.01; left hemisphere: P<0.05). The number of SCVs in the right cerebral hemisphere was significantly and positively correlated with the MMSE and MOCA-B scores (correlation coefficients: 0.246 and 0.201, respectively; P<0.05). The number of SCVs in the left cerebral hemisphere was positively correlated with the MMSE scores (correlation coefficient: 0.196; P<0.05) and the MOCA-B scores. In this study, no significant correlations were observed between cognition and the diameter, length, or tortuosity index of the SCVs in the bilateral cerebral hemispheres. The cognitive function of males was better than that of females, and the different numbers of SCVs may be one of the explanations for this phenomenon of sex-based differences in cognition.