Vessel wall imaging with advanced flow suppression in the characterization of intracranial aneurysms following flow diversion with Pipeline embolization device

BackgroundHigh-resolution vessel wall MRI (VWI) is increasingly used to characterize intramural disorders of the intracranial vasculature unseen by conventional arteriography.ObjectiveTo evaluate the use of VWI for surveillance of flow diverter (FD) treated aneurysms.Materials and methodsRetrospective study of 28 aneurysms (in 21 patients) treated with a FD (mean 57 years; 14 female). All examinations included VWI and a contemporaneously obtained digital subtraction angiogram. Multiplanar pre- and post-gadolinium 3D, variable flip-angle T1 black-blood VWI was obtained using delay alternating nutation for tailored excitation (DANTE) at 3T. 3D time-of-flight MR angiography (MRA) was also carried out. Images were assessed for in-stent stenosis, aneurysm occlusion, presence and pattern/distribution of aneurysmal or parent vessel gadolinium enhancement.ResultsThe VWI-MRI was performed on average at 361±259 days after the intervention. Follow-up DSA was performed at 338±254 days postintervention. Good or excellent black-blood angiographic quality was recorded in 22/28 (79%) pre-contrast and 21/28 (75%) post-contrast VWI, with no cases excluded for image quality. Aneurysm enhancement was noted in 24/28 (85.7%) aneurysms, including in 79% of angiographically occluded aneurysms and 100% of angiographically non-occluded aneurysms. Enhancement of the stented parent-vessel wall occurred significantly more often when aneurysm enhancement was present (92% vs 33%, p=0.049).ConclusionAdvanced VWI produces excellent depiction of FD-treated aneurysms, with robust evaluation of the parent vessel and aneurysm wall to an extent not achievable with conventional MRI/MRA. Gadolinium enhancement may, however, continue even after enduring catheter angiographic occlusion, confounding interpretation, and requiring cognizance of this potentially prolonged effect in such patients.

Deep Learning for Accurate Segmentation of Venous Thrombus from Black-Blood Magnetic Resonance Images: A Multicenter Study

Objective. Deep vein thrombosis (DVT) is the third-largest cardiovascular disease, and accurate segmentation of venous thrombus from the black-blood magnetic resonance (MR) images can provide additional information for personalized DVT treatment planning. Therefore, a deep learning network is proposed to automatically segment venous thrombus with high accuracy and reliability. Methods. In order to train, test, and external test the developed network, total images of 110 subjects are obtained from three different centers with two different black-blood MR techniques (i.e., DANTE-SPACE and DANTE-FLASH). Two experienced radiologists manually contoured each venous thrombus, followed by reediting, to create the ground truth. 5-fold cross-validation strategy is applied for training and testing. The segmentation performance is measured on pixel and vessel segment levels. For the pixel level, the dice similarity coefficient (DSC), average Hausdorff distance (AHD), and absolute volume difference (AVD) of segmented thrombus are calculated. For the vessel segment level, the sensitivity (SE), specificity (SP), accuracy (ACC), and positive and negative predictive values (PPV and NPV) are used. Results. The proposed network generates segmentation results in good agreement with the ground truth. Based on the pixel level, the proposed network achieves excellent results on testing and the other two external testing sets, DSC are 0.76, 0.76, and 0.73, AHD (mm) are 4.11, 6.45, and 6.49, and AVD are 0.16, 0.18, and 0.22. On the vessel segment level, SE are 0.95, 0.93, and 0.81, SP are 0.97, 0.92, and 0.97, ACC are 0.96, 0.94, and 0.95, PPV are 0.97, 0.82, and 0.96, and NPV are 0.97, 0.96, and 0.94. Conclusions. The proposed deep learning network is effective and stable for fully automatic segmentation of venous thrombus on black blood MR images.

Determination of Occupational Disease in Worker with Liver Cirrhosis That Exposed by Vinyl Chloride Superimposed with Hepatitis B Infection

Background: Liver cirrhosis is the final pathological result of various chronic liver diseases that characterized by the formation of regenerative nodules and fibrotic tissue. The etiology of liver cirrhosis are hepatitis C, hepatitis B, alcohol, nonalcoholic fatty liver disease, and can also be caused by chemicals in the workplace. The occupational diagnosis of Liver Cirrhosis that exposed by vinyl chloride superimposed with hepatitis B infection with was performed by using The Seven Steps of Occupational Diagnosis, a method that issued by PERDOKI (Indonesian Occupational Medicine Association-IOMA). The aim of this case report is to determine whether liver cirrhosis in this patient is an occupational disease or not.Case Presentation: Fifty years old man came to Emergency Room with complaints of vomiting black blood since 4 hours. Vomiting blood as much as 5 times with a volume of about 200 cc each time. One day before, patient admitted that his defecation is black, watery, and smell bloody. Volume of defecation was unknown. Three months before, patient complainted that the stomach often felt bloated, enlarged, and got full quickly. There was no icteric in eyes and body.This complaints (vomiting black blood and black stools) were often occured since 2017. In 2017, 2018 and 2020, this patient was hospitalized once while in 2019, the patient was hospitalized twice for this complaint. In 2017, when the complaint first appeared, the patient was declared to have hepatitis B and in 2019, the patient underwent an endoscopy and was said to have enlarged blood vessels in the esophagus, and an abdominal ultrasound was performed and was said to be suspected of liver cirrhosis.This patient works as a family owned chemical industry. The chemical produced is called zamitex, a mixture for paints. These chemicals contain formaldehyde, Vinyl Chloride, and CMC (Carboxymethyl Cellulose). This patient had worked in this field for 21 years, and was exposed to these chemicals. In addition, there are also dangers of heat, awkward positions, and psychosocial.Conclusion: Based on The Seven Steps of Occupational Diagnosis, Liver cirrhosis in this patient can be categorized as an occupational disease superimposed with hepatitis B infection. Liver cirrhosis in this patient can be caused by prolonged exposure to Vinyl Chloride. Vinyl Chloride is known to cause damage to the liver, especially to cause carcinoma of the liver. There is a synergistic effect between exposure to Vinyl Chloride and hepatitis B infection, exacerbating the condition of liver damage. However, because the exposure to Vinyl Chloride has been going on for a longer time, compared to hepatitis B infection, the condition of liver cirrhosis in this patient is still categorized as an occupational disease.

Anatomic Variation of the Lateral Sinus in Patients With Idiopathic Intracranial Hypertension: Delineation With Black-Blood Contrast-Enhanced MRI

Objectives: The purpose of this study was to describe the peculiar anatomic variations in the lateral sinus and analyze the patterns of cerebrospinal fluid (CSF) drainage by using high-resolution (HR) black-blood (BB) contrast-enhanced magnetic resonance imaging (MRI) in patients with idiopathic intracranial hypertension (IIH).Methods: Total 33 IIH patients who were found cerebral venous sinus stenosis (CVSS) by MR venography (MRV) were enrolled in this study. HR-BB contrast-enhanced MRI was used to assess the features of anatomical variations in transverse sinus and sigmoid sinus. The development of bilateral sinuses was firstly evaluated, including unilateral hypoplasia with contralateral dominance or bilateral balanced development. Then, four kinds of anatomical variations were eventually recorded, including circumscribed stenosis, arachnoid granulation (AG), fibrous septum (FS), and brain herniation (BH) into dural venous sinus (DVS).Results: Bilateral venous drainage dysfunction was found in 30(90.9%) patients, whereas only 3(9.1%) patients presented unilateral venous drainage dysfunction. There was no difference in clinical symptoms between the two groups. The most common case is hypoplasia in unilateral sinus combined with anatomic variation in the contralateral dominant transverse sinus such as AG and BH into DVS. Total of 52 anatomic variations were finally found in bilateral sinuses in 33 enrolled patients, including 19(36.5%)AGs, 12(23.1%)FS, 7(13.5%) BH into DVS and 14(26.9%) circumscribed stenoses. Moreover, 41(62.1%) lateral sinuses showed enhancement in T1-weight-enhanced MRI.Conclusions: Patients with CVSS almost had CSF outflow disorders, whatever bilateral equalization or unilateral hypoplasia with contralateral dominance. Four types of main anatomic variations, including circumscribed stenosis, AG, FS, and BH into DVS, caused venous reflux obstruction by elevating the intracranial press (ICP).

Abstract 1122‐000183: Assessing Meningeal Lymphatic MRI Biomarkers in Acute Large Vessel Occlusion Stroke Treated with Thrombectomy

Introduction : Until recently, there was very little known about the brain’s waste removal system. Unlike the peripheral organ systems, the CNS lacked a clearly defined lymphatic vasculature and waste clearance mechanism. However, in 2015, the meningeal lymphatic system (MLS) was first visualized in the dura of humans (1). Since then, a number of studies have investigated the MLS’s potential impact on various neurological diseases, including Alzheimer’s, Parkinson’s, Multiple Sclerosis, hydrocephalus, and epilepsy (2‐6). Other studies have also demonstrated the MLS’s profound influence on stroke (7‐10). However, there is little research that characterizes MLS imaging biomarkers in relation to stroke. Our study evaluates currently proposed MLS MRI biomarkers in large vessel occlusion stroke treated with thrombectomy. Methods : Participants: We recruited twenty patients who had an acute ischemic stroke treated with mechanical thrombectomy (MT) in a large intracranial artery (middle cerebral artery, internal carotid artery, basilar and/or vertebral). The mean age of our population was 69.9 ± 15.5 years. 12 (60%) of our patients had been treated with a combined approach stentriever + aspiration catheter, 4 (20%) with stentriever only, and 4 (20%) with contact aspiration only. Study Design: Basic demographic data, clinical comorbidities, information related to the stroke, technical details about the MT and outcome were collected from electronic medical records. We implemented High Resolution MR Vessel Wall Imaging (HR‐VWI) with a black blood T1‐weighted sequence to characterize changes in the enhancing vessels around the superior sagittal sinus that have been described as potential markers for meningeal lymphatic vessels (1). Within 24 hours after the MT procedure, patients underwent a 45‐minute 3T‐ brain MRI with contrast using a 20‐channel head coil (MAGNETOM Skyra, Siemens) with a sagittal isotropic black blood sequence included with the standard protocol. Our field of view included the superior sagittal sinus. Coronal reconstructed pre‐and post‐contrast back blood T1 sequences were qualitatively evaluated by a board certified Neuroradiologist with 8 years of academic experience evaluating the cerebrovasculature for the presence of purported meningeal lymphatic prominence or asymmetry. Results : There was no significant prominence or asymmetric difference seen in the purported meningeal lymphatics based on 3D high‐resolution T1 black blood MRI sequences in acute stroke large vessel occlusion post‐MT subjects. Conclusions : While in our study no observable differences were seen in the purported meningeal lymphatics based on current MR techniques, it marks an important initial step in development of a useful biomarker for the CNS lymphatic system. Future studies are needed to evaluate alternative meningeal lymphatic quantitative biomarkers. Our study also highlights the need for improved standardization of biomarkers for the meningeal lymphatics. By continuing to evaluate imaging biomarkers, we can further understand the MLS’s potentially profound role in complex neurological diseases.

Correlation of Black Blood MRI with Image- Based Blood Flow Simulations in Intracranial Aneurysms

Intracranial aneurysms (IA) is not-uncommon pathology of cerebral vessels. Vessel wall magnetic resonance imaging can visualize the vascular walls of IAs. In some aneurysms, the wall-adjacent and a luminal hyperintense signal was detected. The signal was attributed to the inflammation and specific hemodynamic features of aneurysms. But, up to now, the studies investigating luminal enhancement combined with flow analysis are limited. Therefore, in this study, investigation of the luminal enhancement is further carried out by comparison to computational fluid dynamics. The latter provides the possibility of calculating hemodynamic parameters, which can give information such as velocity, pressure, and shear stress fields throughout a heart cycle. The data of the IAs is specific to each patient and builds the basis for the enhancement analysis and simulations. Specific hemodynamic parameters like kinetic energy and vortex formation evaluated in the simulations show a dependency to signal suppression recorded with vessel wall magnetic resonance imaging

Primary phlebitis of central nervous system revealed by black-blood magnetic resonance imaging

Primary phlebitis of the central nervous system (PPCNS) is a rare condition that might be a subset of primary angiitis of the CNS. In this case report, the patient was a 39-year-old man with a 2-week history of anterograde amnesia and abnormal behaviours. Black-blood MRI (BB-MRI) showed contrast enhancement of the left basilar vein and cerebral superficial veins. Angiography showed unremarkable change in arteries. After a thorough differential diagnosis, we diagnosed PPCNS and then administered methylprednisolone pulse and cyclophosphamide pulse. The neuropsychological symptoms and MRI findings gradually improved, and after 2 months, the dose of prednisolone was gradually reduced to 20 mg. No recurrence was observed. This case shows that BB-MRI may be useful for diagnosing PPCNS.