Resolution Magnetic Imaging Research Articles

Paget Disease of the Breast: An Uncommon Case Report

Paget’s breast disease is a rare malignancy with an incidence of 0.7% to 4.3% among all primary breast cancer. It’s characterized by an eczemous and ulcerative lesion of the nipple area. It’s associated up to 90% to an underlying invasive carcinoma or carcinoma in situ. Upon every cutaneous lesion matching the description above in women in their fifth or sixth decade, a punch biopsy should be performed. Imaging investigations rely on mammography, breast ultrasound and most importantly on Magnetic resolution imaging (MRI). Treatment management offers a wide array of options ranging from total mastectomy with sentinel node biopsy to non-surgical and non-invasive therapy. We present the uncommon case of a 49 years old female presented to our facility with Paget breast disease treated by breast conserving surgery.

Bimagnetic Core/Shell Nanoprobes with Tunable Exchange Coupling for High Resolution and Sensitive Magnetic Particle Imaging

Magnetic particle imaging (MPI) has demonstrated versatile applications in biomedicine, including tumor imaging, cell tracking, and image‐guided hyperthermia. Despite these advancements, the prevalent use of clinically approved tracers has posed limitations on MPI's resolution and sensitivity. In this study, we engineered a bimagnetic core/shell nanocrystals (BMCS) tailored for MPI by optimizing the heterostructure and modulating the exchange coupling effect between the two magnetic components. The resulting BMCS exhibited remarkably heightened susceptibility and magnetization while maintaining low coercivity, thereby substantially improved both MPI resolution and sensitivity compared to conventional tracers such as VivoTrax. At an equivalent mass concentration, BMCS demonstrated a notable 5.08‐fold increase in signal intensity and achieved an unprecedentedly high resolution down to 1 mm. The excellent MPI performance contributes to high resolution MPI and the sensitive detection of orthotopic colorectal cancer in mice. The design strategy employed in BMCS, centered on the exchange coupling effect, introduces an efficacious approach for the development of high performance MPI tracers.

Bimagnetic Core/Shell Nanoprobes with Tunable Exchange Coupling for High Resolution and Sensitive Magnetic Particle Imaging.

Magnetic particle imaging (MPI) has demonstrated versatile applications in biomedicine, including tumor imaging, cell tracking, and image-guided hyperthermia. Despite these advancements, the prevalent use of clinically approved tracers has posed limitations on MPI's resolution and sensitivity. In this study, we engineered a bimagnetic core/shell nanocrystals (BMCS) tailored for MPI by optimizing the heterostructure and modulating the exchange coupling effect between the two magnetic components. The resulting BMCS exhibited remarkably heightened susceptibility and magnetization while maintaining low coercivity, thereby substantially improved both MPI resolution and sensitivity compared to conventional tracers such as VivoTrax. At an equivalent mass concentration, BMCS demonstrated a notable 5.08-fold increase in signal intensity and achieved an unprecedentedly high resolution down to 1 mm. The excellent MPI performance contributes to high resolution MPI and the sensitive detection of orthotopic colorectal cancer in mice. The design strategy employed in BMCS, centered on the exchange coupling effect, introduces an efficacious approach for the development of high performance MPI tracers.

Automatic Segmentation Model for Parkinson’s Images Based on SA-U2-Net

To effectively solve the problem of a small proportion of substantia nigra and midbrain regions in Magnetic Resolution Imaging (MRI) images of Parkinson’s disease (PD) patients, unclear boundaries with surrounding tissues, and difficulty in accurately delineating boundaries, an improved U2-Net algorithm for Parkinson’s substantia nigra midbrain image segmentation was proposed. This algorithm first improves the Residual U-blocks (RSU) and RSU-4F modules using the Shuffle Attention (SA) module, enhancing the network’s attention to Parkinson’s substantia nigra and midbrain blurry regions in the encoding and decoding layers. Next, replace some ordinary convolutions in RSU-4F with DynamicConv (DyConv), capture local features through dynamic convolution kernels, and improve the segmentation performance of Parkinson’s images. The experimental data used clinical data, and the improved algorithm achieved Dice, Precision, Recall, and mIou of 80.27%, 89.99%, 88.88%, and 82.38% in substantia nigra segmentation, respectively. The experimental results show that this algorithm can achieve more precise segmentation of Parkinson’s images.

Preoperative visualization of the greater occipital nerve with magnetic resonance imaging in candidates for occipital nerve decompression for headaches

Occipital nerve decompression is effective in reducing headache symptoms in select patients with migraine and occipital neuralgia. Eligibility for surgery relies on subjective symptoms and responses to nerve blocks and Onabotulinum toxin A (Botox) injections. No validated objective method exists for detecting occipital headache pathologies. The purpose of the study is to explore the potential of high-resolution Magnetic Resolution Imaging (MRI) in identifying greater occipital nerve (GON) pathologies in chronic headache patients. The MRI protocol included three sequences targeting fat-suppressed fluid-sensitive T2-weighted signals. Visualization of the GON involved generating 2-D image slices with sequential rotation to track the nerve course. Twelve patients underwent pre-surgical MRI assessment. MRI identified four main pathologies that were validated against intra-operative examination: GON entanglement by the occipital artery, increased nerve thickness and hyperintensity suggesting inflammation compared to the non-symptomatic contralateral side, early GON branching with rejoining at a distal point, and a connection between the GON and the lesser occipital nerve. MRI possesses the ability to visualize the GON and identify suspected trigger points associated with headache symptoms. This case series highlights MRI's potential to provide objective evidence of nerve pathology. Further research is warranted to establish MRI as a gold standard for diagnosing extracranial contributors in headaches.

High resolution magnetic field imaging probe with two rows of TMR sensors for small defects inspection

It is still a challenging problem to detect small defects for eddy current array probes, which requires the probes to possess excellent sensitivity, as well as high spatial resolution. This paper presents a novel high-resolution magnetic field imaging probe with two rows of tunneling magnetoresistance (TMR) array sensors. The bare die sensors are integrated on a printed circuit board by golden wire bonding technology. The two rows of sensors are placed staggered with each other. The data of the two arrays are merged into a matrix, in which way the image pixel pitch is increased to 0.25 mm. The probe employs a differential scheme to suppress the noise, so as to detect the weak signal of small defects. To highlight the weak defect indications, feature extraction and segmentation algorithms are developed. The experimental results confirm that the proposed method can inspect a small defect with dimensions 1 mm (length) × 0.1 mm (width) × 0.1 mm (depth) on a stainless-steel sample.

Research Status and Development Trend of EEG Technology for Deep Learning in Emotion Recognition

EEG technology has made significant progress as people's attention to their emotions increases. This has also led to significant progress in various brain sciences, as well as their correlation with emotions. Nevertheless, based on the development of contemporary brain science, it is not possible to provide detailed cause analysis or draw accurate conclusions based on EEG information for a certain symptom or representation. The brain, as a complex organ of multiple entities, processes complex information by connecting multiple brain regions and clarifying the division of labor for each region. This creates a significant obstacle for the research method of brain computer interface, which uses computer algorithms to read information in the brain. Recently, many solutions and research methods have emerged to address this issue, such as electroencephalography (EEG), Positive Positron Emission Computed Tomography (PET) and Functional Magnetic Resolution Imaging (fMRI), etc. However, with such a large number of technologies, a method that can provide precise data from both temporal and spatial angles has not yet been derived. So in-depth research in biology, continuous exploration of computer algorithms can make outstanding contributions to the refinement of brain computer data. In summary, this article aims to provide an overview of the relationship between emotions and EEG analysis, as well as the principles of machine recognition and other applied technologies.

Imaging investigation of cervicocranial artery dissection by using high resolution magnetic resonance VWI and MRA: qualitative and quantitative analysis at different stages

BackgroundTo explore the value of magnetic resonance angiography (MRA) and high resolution magnetic resonance vessel wall imaging (HRMR-VWI) in cervicocranial artery dissection (CCAD) for the disease diagnosis, course staging and treatment. On the basis of qualitative evaluation, this study also extract the changes of different stages in vessel wall in different vessel segments to identify imaging indicators for the quantitative evaluation of CCAD.MethodsWe retrospectively enrolled 34 patients with CCAD (38branches) with conventional MRA and HRMR-VWI examinations. Two radiologists independently analyzed imaging features of vessel wall and lumen in the different stages, and the typical sign detection of artery dissection were compared between MRA and HRMR-VWI. Then the parameters of vessel wall was quantitatively evaluated by the post-processing software (Vesselmass, Leiden University Medical Center, Leiden, The Netherlands.ResultsHRMR-VWI revealed typical sign detection of artery dissection in all patients in the acute and subacute stage. Among them, the intimal flap/double lumen sign ditection were more common than the MRA, there was significant difference (P = 0.012). MRA revealed typical sign detection of artery dissection in more than half the patients, and the detection was no significant difference at the chronic stage between MRA and HRMR-VWI (P = 1.000/1.000/0.761). In the acute and subacute stage, the typical sign detection of intramural hematoma and Grade II enhancement revealed by HR-MRI was higher than the observations in the chronic stage (P = 0.000/0.000/0.016), while there was no significant difference by MRA (P = 0.902). The values of wall thickness, relative signal intensity of vessel wall enhancement, relative signal intensity of intramural hematoma (IMH), and percentage of stenosis in CCAD decreased from acute to subacute and then to chronic stages. Each quantitative parameter in patients with CCAD in the early stages (i.e., acute and subacute stages) was significantly different from that in patients with CCAD in the recovered group at chronic stage (P < 0.05). Wall thickness and relative signal intensity of vessel wall enhancement in patients with CCAD in the early stages were not significantly different from those in patients with CCAD in the incompletely recovered group at chronic stage (P > 0.05).ConclusionsAs the only noninvasive imaging technology, HRMR-VWI displays the structure of the vessel wall in vivo, showing not only excellent performance in the early diagnosis of CCAD, but also describing the changes of different stages in the qualitative and quantitative characteristics of vessel wall. It also helps to guide the diseasediagnosis, course staging and treatment of CCAD. Although the diagnostic efficacy of MRA was not as good as HRMR-VWI, it should be the first choice of method for routine examination in evaluating CCAD, especially at the chronic stage of CCAD.

Intravesical Contrast-Enhanced MRI: A Potential Tool for Bladder Cancer Surveillance and Staging.

This review article gives an overview of the current state of the art of bladder cancer imaging and then discusses in depth the scientific and technical merit of a novel imaging approach, tracing its evolution from murine cancer models to cancer patients. While the poor resolution of soft tissue obtained by widely available imaging options such as abdominal sonography and radiation-based CT leaves them only suitable for measuring the gross tumor volume and bladder wall thickening, dynamic contrast-enhanced magnetic resolution imaging (DCE MRI) is demonstrably superior in resolving muscle invasion. However, major barriers still exist in its adoption. Instead of injection for DCE-MRI, intravesical contrast-enhanced MRI (ICE-MRI) instills Gadolinium chelate (Gadobutrol) together with trace amounts of superparamagnetic agents for measurement of tumor volume, depth, and aggressiveness. ICE-MRI leverages leaky tight junctions to accelerate passive paracellular diffusion of Gadobutrol (604.71 Daltons) by treading the paracellular ingress pathway of fluorescein sodium and of mitomycin (<400 Daltons) into bladder tumor. The soaring cost of diagnosis and care of bladder cancer could be mitigated by reducing the use of expensive operating room resources with a potential non-surgical imaging option for cancer surveillance, thereby reducing over-diagnosis and over-treatment and increasing organ preservation.

Effective detection of Alzheimer's disease by optimizing fuzzy K-nearest neighbors based on salp swarm algorithm

Alzheimer's disease (AD) is a typical senile degenerative disease that has received increasing attention worldwide. Many artificial intelligence methods have been used in the diagnosis of AD. In this paper, a fuzzy k-nearest neighbor method based on the improved binary salp swarm algorithm (IBSSA-FKNN) is proposed for the early diagnosis of AD, so as to distinguish between patients with mild cognitive impairment (MCI), Alzheimer's disease (AD) and normal controls (NC). First, the performance and feature selection accuracy of the method are validated on 5 different benchmark datasets. Secondly, the paper uses the Structural Magnetic Resolution Imaging (sMRI) dataset, in terms of classification accuracy, sensitivity, specificity, etc., the effectiveness of the method on the AD dataset is verified. The simulation results show that the classification accuracy of this method for AD and MCI, AD and NC, MCI and NC are 95.37%, 100%, and 93.95%, respectively. These accuracies are better than the other five comparison methods. The method proposed in this paper can learn better feature subsets from serial multimodal features, so as to improve the performance of early AD diagnosis. It has a good application prospect and will bring great convenience for clinicians to make better decisions in clinical diagnosis.

Abstract WP101: Vessel Wall Enhancement Is Associated With Symptomatic Adult Moyamoya Disease And Syndrome In An American Population

Introduction: Moyamoya Disease (MMD) and Moyamoya Syndrome (MMS) are chronic progressive cerebrovascular disease characterized by bilateral or unilateral stenotic arteries around the circle of Willis with subsequent development of collateral blood vessels. MMS is associated with conditions such as Down Syndrome (DS) or sickle cell disease (SCD). The presence of vessel wall enhancement (VWE) on high resolution magnetic resonance vessel wall imaging (HR MR VWI) in MMD or MMS is controversial. Recent studies suggest VWE is associated with recent ischemic or hemorrhagic stroke. The significance of VWE in MMD or MMS in non-Asian population has not been well established. Our study aimed to investigate the prevalence of VWE in adult MMD/MMS in the United States and identify its predictive value for stenosis progression. Methods: We retrospectively reviewed patients with MMD or MMS admitted to Clements University Hospital and Parkland Memorial Hospital affiliated with University of Texas Southwestern Medical Center from January 2014 to March 2022. Patients were included if HR MR VWI was performed during workup. Patients were excluded if intracranial atherosclerosis was the suspected stroke etiology from cardiovascular risk factors. The presence of the VWE on HR MR VWI and stenosis grading were evaluated by blinded neuroradiologists and vascular neurologists. Symptomatic disease was defined as ischemic stroke, hemorrhagic stroke or transient ischemic attack within 24 months before HR MR VWI was obtained. Results: A total of 32 patients were included, of which 28 had MMD, 3 had MMS from SCD and 1 had MMS from DS. Mean age at diagnosis was 34 ± 10 years old, and 29 (90.6%) were female. VWE was seen in 22 (68.8%) patients. VWE is more common in symptomatic disease than asymptomatic disease (95% vs 20%). 24 patients had follow up MR angiogram with average time from HR MR VWI of 25.8 ± 16.7 months. Among 12 patients with 16 non-occlusive arteries, stenosis progression was seen in 67% of arteries with VWE compared to 25% of arteries without VWE. Conclusions: In a North American population with MMD or MMS, VWE on HR MR VWI was more common in symptomatic disease. The presence of VWE was associated with increased risk of stenosis progression. More studies are needed to confirm these findings.

Hardware Trojan Detection Using Unsupervised Deep Learning on Quantum Diamond Microscope Magnetic Field Images

This article presents a method for hardware trojan detection in integrated circuits. Unsupervised deep learning is used to classify wide field-of-view (4 × 4 mm 2 ), high spatial resolution magnetic field images taken using a Quantum Diamond Microscope (QDM). QDM magnetic imaging is enhanced using quantum control techniques and improved diamond material to increase magnetic field sensitivity by a factor of 4 and measurement speed by a factor of 16 over previous demonstrations. These upgrades facilitate the first demonstration of QDM magnetic field measurement for hardware trojan detection. Unsupervised convolutional neural networks and clustering are used to infer trojan presence from unlabeled data sets of 600 × 600 pixel magnetic field images without human bias. This analysis is shown to be more accurate than principal component analysis for distinguishing between field programmable gate arrays configured with trojan-free and trojan-inserted logic. This framework is tested on a set of scalable trojans that we developed and measured with the QDM. Scalable and TrustHub trojans are detectable down to a minimum trojan trigger size of 0.5% of the total logic. The trojan detection framework can be used for golden-chip-free detection, since knowledge of the chips’ identities is only used to evaluate detection accuracy.

Role of contrast-enhanced flair sequence in magnetic resonance imaging for evaluating intracranial pathologies

Background: Magnetic resolution imaging (MRI) has superior soft tissue contrast for characterization and diagnosing various intracranial lesions. Various MRI techniques are used for characterizing intracranial lesions. Post contrast T1 imaging is the traditional technique used for assessing lesion contrast enhancement. This study intends to assess the use of post contrast Fluid Attenuated Inversion Recovery (FLAIR) imaging for assessing lesion contrast enhancement. Results: The participants were analyzed by age, gender, number of lesions observed for each participant, signal intensity pattern for all intracranial lesions on both post contrast sequences, comparison of degree of contrast enhancement of all intracranial lesions on both post contrast sequences, comparison between various intra-axial & extra-axial intracranial lesions on both post contrast sequences, comparison between various intracranial lesions based on their etiology on both post contrast sequences and comparison of each intracranial lesion on both post contrast sequences. Conclusion: The study suggests that the overall degree of contrast enhancement is superior for contrast enhanced T1 sequences for the majority of the lesions, however complete lesion pathology cannot be assessed on this sequence alone. Although post contrast FLAIR sequence has shown greater degree of contrast enhancement in infectious meningitis, hemangioblastoma and toxoplasmosis, this was not statistically significant (p value >0.05) possibly owing to less sample size. Hence, further studies with more sample size should be assessed to establish the significance. Therefore, contrast enhanced FLAIR sequence is an important adjunct for imaging of the various intracranial pathologies and should be incorporated for evaluating various intracranial pathologies.

Postpartum Recurrent Mastitis Despite Resolution of Prior Prolactinoma

We present a 35-year-old woman with history of a prolactinoma who presented 11 weeks postpartum with recurrent mastitis. Per the patient, in the past she took cabergoline but stopped about 5 years previously. Despite attempts to wean, postpartum, she continued to express an excessive amount of breast milk. Magnetic resolution imaging revealed a slightly heterogeneous appearance of the pituitary gland, and she was started on dopaminergic agents. This case demonstrates that significant lactotroph hyperplasia can occur after breastfeeding ends despite the resolution of a prior prolactin-secreting microadenoma.

Late Metastatic Renal Cell Carcinoma Recurrence Presenting as a Maxillary Sinus Mass 12 Years after Nephrectomy: Case Report and Literature Review

Metastasis to the sinonasal cavity is rare. Late recurrence, such as metastasis developing 10 years or more after nephrectomy, is even more rare. We present a rare case of late metastatic renal cell carcinoma (RCC) in the maxillary sinus after nephrectomy and discuss reported sinonasal metastatic RCC cases. A 64-year-old man presented with left nasal obstruction for the previous one year. He had undergone right nephrectomy to treat RCC 12 years prior. Paranasal sinus computed tomography and magnetic resolution imaging revealed a 4.6-cm-diameter mass exhibiting delayed contrast enhancement that filled the left maxillary sinus and the nasal cavity. Histologically, clear cell RCC was diagnosed. We resected the maxillary sinus tumor to resolve the nasal obstruction for palliative symptom relief. There has been no evidence of recurrence to date, 3 years postoperatively. When a patient with a history of RCC presents with a hypervascular paranasal sinus mass, metastatic RCC should be considered, despite history of nephrectomy. It is important to make an appropriate treatment plan depending on extent of metastases and location of the metastatic tumor.

Neurolymphomatosis: a single-center experience of neuromuscular manifestations, treatments, and outcomes.

Neurolymphomatosis (NL) is a disease characterized by the infiltration of malignant lymphocytes into the peripheral nervous system. We report clinical features, radiographic findings, modes of treatment, and outcomes of patients with NL. We retrospectively investigated patients with NL. We extracted data, including clinical features, magnetic resolution imaging (MRI), 18F-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scans, cerebrospinal fluid cytology findings, the results of electrodiagnostic studies, as well as patient treatments and outcomes. Ten NL patients were identified. All patients reported pain/paresthesia and weakness in the affected area. The MRI scans were abnormal in eight out of nine patients with an enhancement of the spinal nerve root, plexus, peripheral nerve trunk, and cranial nerve. The FDG PET/CT scans were positive in all patients. Radiculopathy or radiculoplexopathy was the most common electrodiagnostic finding. Neurological improvement was observed in only three patients. The condition of the nine patients who underwent multimodality treatments for cancer eventually deteriorated and the patients died. NL should be considered in the differential diagnosis of any type of neuropathy in patients with lymphoma. Because it could be confused with other neuropathies in lymphoma and various musculoskeletal diseases, a high index of suspicion and familiarity with clinical manifestation of NL are key. FDG PET/CT was the most sensitive diagnostic imaging modality to detect relevant neural invasion. The root within the spinal neural foramen was the most frequently affected neural structure. Early diagnosis of this rare neurologic manifestation of lymphoma may improve treatment outcomes.

Profiles of Cortical Visual Impairment (CVI) Patients Visiting Pediatric Outpatient Department

Cortical visual impairment denotes vision loss from pathology posterior to the lateral geniculate nucleus. The pathology may involve the optic radiations, as well as the occipital cortex. To find out the profiles of cortical visual impairment patients visiting the pediatric outpatient department. The study is a hospital based retrospective study in which all consecutive patients diagnosed with cortical visual impairment were included. A total of 40 patients were collected. Detailed history taking and clinical examination was done. Visual acuity was taken by fixation and follows method. Among 40 patients, only two patients were advised to use glass and the rest did not have significant refractive error. Myopia ranged from (-2D to -5D) and five patients were myopic. Astigmatism ranged from (-0.5 to -2.5 x 108°) and 10 patients had astigmatism. Suspected patients were advised for Computed Tomography/ Magnetic Resolution Imaging (CT/MRI) of the brain. The male: female ratio was 3:2, the age group ranged from 4 months to 8 years old, antenatal checkup history was uneventful in 77.5% cases, history of birth asphyxia was present in 87.5% cases, postnatal checkup history was eventful in 67.5%, associated systemic illness was present in 60%, anterior segment examination was normal in 92.5%, posterior segment examination was normal in 72.5%, CT/MRI findings were abnormal in 57.5% and was not done in 30% of cases. Antenatal history was described as uneventful if there was absence of diabetes mellitus, hypertension, fever and intake of any medicine. Postnatal history was described as uneventful if there was absence of febrile convulsion, meningitis, encephalocele, encephalopathy, epilepsy or hydrocephalus. Birth asphyxia and postnatal infections are the major causes for cortical visual impairment. We can mitigate cortical visual impairment by limiting birth asphyxia and postnatal infections.

Arterial culprit plaque characteristics revealed by magnetic resonance Vessel Wall imaging in patients with single or multiple infarcts

PurposeTo investigate characteristics of intra- and extracranial arterial culprit plaques between patients with single infarct and multiple-infarcts by a head-neck combined high resolution magnetic resonance vessel wall imaging (HR-MRVWI). Materials and methodsForty-three patients with recent ischemic stroke due to large artery atherosclerosis were enrolled. The head-neck combined HR-MRVWI was performed in all patients both pre- and post-contrast administration. Based on diffusion weighted imaging findings, patients were divided into single-infarction and multiple-infarction groups. For patients with anterior circulation ischemic stroke, they were also divided into perforating artery infarction (PAI) and non-PAI groups. Patient demographics, number and location of culprit plaques, artery stenosis percentage, intraplaque hemorrhage, and plaque enhancement were evaluated and compared between single-infarction and multiple-infarction groups, as well as between PAI and non-PAI groups. ResultsA total of 83 culprit plaques were identified. The artery stenosis degree was more severe and plaque enhancement more prominent in multiple-infarction group than in single-infarction group. Patients with multiple infarcts also had more culprit plaques per patient than those with single infarct, which contributed to the occurrence of multiple infarcts. For comparison of PAI and non-PAI groups, a higher artery stenosis percentage was observed in non-PAI group, and patients with non-PAI had more culprit plaques per patient, which contributed to a variety of infarct manifestations. ConclusionA higher stenosis grade and higher number of culprit plaques seem to be associated with a higher number of cerebral infarcts in patients with large artery atherosclerosis.

Practical value of three-dimensional high resolution magnetic resonance Vessel Wall imaging in identifying suspicious intracranial vertebrobasilar dissecting aneurysms

BackgroundDirect evidence of intimal flaps, double lumen and intramural haematomas (IMH) is difficult to detect on conventional angiography in most intracranial vertebrobasilar dissecting aneurysms (VBDAs). Our purpose was to assess the value of three-dimensional high-resolution magnetic resonance vessel wall imaging (3D HRMR VWI) for identifying VBDAs.MethodsBetween August 2013 and January 2016, consecutive patients with suspicious VBDAs were prospectively enrolled to undergo catheter angiography and VWI (pre- and post-contrast). The lesion was diagnosed as definite VBDA when presenting direct signs of dissection; as possible when only presenting indirect signs; and as segmental ectasia when there was local dilation and wall thickness similar to adjacent normal artery’s without mural thrombosis.ResultsTwenty-one patients with 27 lesions suspicious for VBDAs were finally included. Based on findings of VWI and catheter angiography, definite VBDA was diagnosed in 25 and 7 lesions (92.6%, vs 25.9%, p < 0.001), respectively; possible VBDA in 0 and 20 (0 vs 74.1%), respectively; and segmental ectasia in 2 and 0 (7.4% vs 0%), respectively. On VWI and catheter angiography, intimal flap was detected in 21 and 7 lesions (77.8% vs 25.9%, p = 0.001), respectively; double lumen sign in 18 and 7 (66.7% vs 25.9%, p = 0.003), respectively; and IMH sign in 14 and 0 (51.9% vs 0), respectively.Conclusions3D HRMR VWI could detect direct dissection signs more frequently than catheter angiography. This may help obtain definite diagnosis of intracranial VBDAs, and allow accurate differentiation between dissecting aneurysm and segmental ectasia as well. Further prospective study with larger sample was required to investigate the superiority of HRMR VWI for definite diagnosis of intracranial VBDAs than catheter angiography.

Application value of preoperative high-resolution magnetic resonance vessel wall imaging evaluation on symptomatic middle cerebral artery stenosis stenting

Objective To investigate the value of preoperative high-resolution magnetic resonance vessel wall imaging (HRMR-VWI) in stenosis stenting for symptomatic middle cerebral artery. Methods The clinical data of 35 patients with atherosclerotic stenosis in middle cerebral artery (MCA) M1 segment who were treated with stenting therapy (stenting angioplasty) at Department of Neurosurgery, Tianjin Huanhu Hospital from August 2011 to May 2019 were analyzed retrospectively. HRMR-VWI results were used to evaluate the location, composition and stability of plaques before operation. The mortality and morbidity at 30 days post operation were determined by clinical follow-up. The ischemic stroke and restenosis rates at 12 months post operation were confirmed by imaging follow-up. Results The preoperative HRMR-VWI of 35 patients showed that the plaques in 15 cases were located on the ventral vessel wall, those in 12 on the inferior, and those in 8 on the upper vessel wall. Seven patients had unstable plaques in the M1 segment of MCA. The stents were successfully placed in 35 patients and well adhered with smooth blood flow. Technical complications occurred in 2 (5.7%) patients. One patient (2.8%) died of cerebral hernia due to reperfusion hemorrhage in 30 days after surgery, although decompressive craniectomy and hematoma clearing were performed. One patient (2.8%) had residual neurological dysfunction. Twelve months after the operation, no ischemic stroke occurred in 34 patients, and no restenosis occurred in the 5 patients who were followed up by imaging. Conclusion HRMR-VWI has a high diagnostic value for the location and stability of plaques in stenotic sites of MCA, which could improve the safety and effectiveness of stenting of MCA M1 segment stenosis. Key words: Middle cerebral artery; Endovascular procedures; Stents; Atherosclerotic stenosis; High resolution magnetic resonance vessel wall imaging