scholarly journals Semiautomated 3D mapping of aneurysmal wall enhancement with 7T-MRI

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ashrita Raghuram ◽  
Alberto Varon ◽  
Jorge A. Roa ◽  
Daizo Ishii ◽  
Yongjun Lu ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
3D Imaging ◽  
High Resolution Imaging ◽  
Biological Processes ◽  
Automated Method ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Potential Biomarker ◽  
Resolution Imaging ◽  
Objective Tool

AbstractAneurysm wall enhancement (AWE) after the administration of contrast gadolinium is a potential biomarker of unstable intracranial aneurysms. While most studies determine AWE subjectively, this study comprehensively quantified AWE in 3D imaging using a semi-automated method. Thirty patients with 33 unruptured intracranial aneurysms prospectively underwent high-resolution imaging with 7T-MRI. The signal intensity (SI) of the aneurysm wall was mapped and normalized to the pituitary stalk (PS) and corpus callosum (CC). The CC proved to be a more reliable normalizing structure in detecting contrast enhancement (p < 0.0001). 3D-heatmaps and histogram analysis of AWE were used to generate the following metrics: specific aneurysm wall enhancement (SAWE), general aneurysm wall enhancement (GAWE) and focal aneurysm wall enhancement (FAWE). GAWE was more accurate in detecting known morphological determinants of aneurysm instability such as size ≥ 7 mm (p = 0.049), size ratio (p = 0.01) and aspect ratio (p = 0.002). SAWE and FAWE were aneurysm specific metrics used to characterize enhancement patterns within the aneurysm wall and the distribution of enhancement along the aneurysm. Blebs were easily identified on 3D-heatmaps and were more enhancing than aneurysm sacs (p = 0.0017). 3D-AWE mapping may be a powerful objective tool in characterizing different biological processes of the aneurysm wall.

Role of apoptosis in intracranial aneurysm rupture

2004 ◽  
Vol 101 (6) ◽  
pp. 1018-1025 ◽  
Author(s):  
Luigi Pentimalli ◽  
Andrea Modesti ◽  
Andrea Vignati ◽  
Enrico Marchese ◽  
Alessio Albanese ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Superficial Temporal Artery ◽  
Aneurysm Rupture ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Content Type ◽  
Unruptured Aneurysms ◽  
Ruptured Aneurysms ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Fine Print

Object. Mechanisms involved in the rupture of intracranial aneurysms remain unclear, and the literature on apoptosis in these lesions is extremely limited. The hypothesis that apoptosis may reduce aneurysm wall resistance, thus contributing to its rupture, warrants investigation. The authors in this study focused on the comparative evaluation of apoptosis in ruptured and unruptured intracranial aneurysms. Peripheral arteries in patients harboring the aneurysms and in a group of controls were also analyzed. Methods. Between September 1999 and February 2002, specimens from 27 intracranial aneurysms were studied. In 13 of these patients apoptosis was also evaluated in specimens of the middle meningeal artery (MMA) and the superficial temporal artery (STA). The terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling technique was used to study apoptosis via optical microscopy; electron microscopy evaluation was performed as well. Apoptotic cell levels were related to patient age and sex, aneurysm volume and shape, and surgical timing. Significant differences in apoptosis were observed when comparing ruptured and unruptured aneurysms. High levels of apoptosis were found in 88% of ruptured aneurysms and in only 10% of unruptured lesions (p < 0.001). Elevated apoptosis levels were also detected in all MMA and STA specimens obtained in patients harboring ruptured aneurysms, whereas absent or very low apoptosis levels were observed in MMA and STA specimens from patients with unruptured aneurysms. A significant correlation between aneurysm shape and apoptosis was found. Conclusions. In this series, aneurysm rupture appeared to be more related to elevated apoptosis levels than to the volume of the aneurysm sac. Data in this study could open the field to investigations clarifying the causes of aneurysm enlargement and rupture.

scholarly journals Vessel wall magnetic resonance imaging in intracranial aneurysms: Principles and emerging clinical applications

2019 ◽  
Vol 26 (2) ◽  
pp. 135-146 ◽  
Author(s):  
Corrado Santarosa ◽  
Branden Cord ◽  
Andrew Koo ◽  
Pervinder Bhogal ◽  
Ajay Malhotra ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Vessel Wall ◽  
Intracranial Aneurysms ◽  
High Volume ◽  
Resonance Imaging ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Technical Principles

Intracranial high-resolution vessel wall magnetic resonance imaging is an imaging paradigm that complements conventional imaging modalities used in the evaluation of neurovascular pathology. This review focuses on the emerging utility of vessel wall magnetic resonance imaging in the characterization of intracranial aneurysms. We first discuss the technical principles of vessel wall magnetic resonance imaging highlighting methods to determine aneurysm wall enhancement and how to avoid common interpretive pitfalls. We then review its clinical application in the characterization of ruptured and unruptured intracranial aneurysms, in particular, the emergence of aneurysm wall enhancement as a biomarker of aneurysm instability. We offer our perspective from a high-volume neurovascular center where vessel wall magnetic resonance imaging is in routine clinical use.

scholarly journals Computational fluid dynamics of cerebral aneurysm coiling using high-resolution and high-energy synchrotron X-ray microtomography: comparison with the homogeneous porous medium approach

2016 ◽  
Vol 9 (8) ◽  
pp. 00.1-00 ◽  
Author(s):  
Michael R Levitt ◽  
Michael C Barbour ◽  
Sabine Rolland du Roscoat ◽  
Christian Geindreau ◽  
Venkat K Chivukula ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Porous Medium ◽  
High Resolution ◽  
Computational Modeling ◽  
Intracranial Aneurysms ◽  
High Resolution Imaging ◽  
X Ray ◽  
Hemodynamic Variables ◽  
Homogeneous Porous Medium ◽  
Resolution Imaging

BackgroundComputational modeling of intracranial aneurysms provides insights into the influence of hemodynamics on aneurysm growth, rupture, and treatment outcome. Standard modeling of coiled aneurysms simplifies the complex geometry of the coil mass into a homogeneous porous medium that fills the aneurysmal sac. We compare hemodynamics of coiled aneurysms modeled from high-resolution imaging with those from the same aneurysms modeled following the standard technique, in an effort to characterize sources of error from the simplified model.MaterialsPhysical models of two unruptured aneurysms were created using three-dimensional printing. The models were treated with coil embolization using the same coils as those used in actual patient treatment and then scanned by synchrotron X-ray microtomography to obtain high-resolution imaging of the coil mass. Computational modeling of each aneurysm was performed using patient-specific boundary conditions. The coils were modeled using the simplified porous medium or by incorporating the X-ray imaged coil surface, and the differences in hemodynamic variables were assessed.ResultsX-ray microtomographic imaging of coils and incorporation into computational models were successful for both aneurysms. Porous medium calculations of coiled aneurysm hemodynamics overestimated intra-aneurysmal flow, underestimated oscillatory shear index and viscous dissipation, and over- or underpredicted wall shear stress (WSS) and WSS gradient compared with X-ray-based coiled computational fluid dynamics models.ConclusionsComputational modeling of coiled intracranial aneurysms using the porous medium approach may inaccurately estimate key hemodynamic variables compared with models incorporating high-resolution synchrotron X-ray microtomographic imaging of complex aneurysm coil geometry.

Determinants of Gadolinium-Enhancement of the Aneurysm Wall in Unruptured Intracranial Aneurysms

Neurosurgery ◽  
2017 ◽  
Vol 83 (4) ◽  
pp. 719-725 ◽  
Author(s):  
Daan Backes ◽  
Jeroen Hendrikse ◽  
Irene van der Schaaf ◽  
Ale Algra ◽  
Antti E Lindgren ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Gadolinium Enhancement ◽  
Adjusted Risk ◽  
Aneurysm Size ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Aneurysm Growth ◽  
Risk Ratios ◽  
Aneurysm Shape ◽  
Wall Imaging

Abstract BACKGROUND Recent studies suggest that gadolinium-enhancement of the aneurysm wall may reflect aneurysm wall inflammation, which might increase the risk of aneurysm growth or rupture. OBJECTIVE To determine the prevalence of gadolinium-enhancement and its determinants in patients with predominantly small (&lt;7 mm) unruptured intracranial aneurysms. METHODS We performed 3 T MRI aneurysm wall imaging in patients with ≥1 unruptured aneurysm. With Poisson regression analysis, we calculated crude and adjusted risk ratios (RRs) with 95% confidence intervals (CI) to assess determinants of gadolinium-enhancement. RESULTS Gadolinium-enhancement was observed in 25/79 patients (32%; 95% CI: 21%-42%) and 26/89 aneurysms (29%; 95% CI: 20%-39%). With aneurysms 1.0-2.9 mm as reference, RRs were 4.6 (95% CI: 0.6-36.5) for 3.0 to 4.9 mm, 9.4 (95% CI: 1.3-67.2) for 5.0 to 6.9 mm, and 14.8 (95% CI: 2.1-104.6) for ≥7.0 mm. With internal carotid artery as reference, RRs adjusted for aneurysm size were 3.6 (95% CI: 1.1-11.4) for posterior communicating artery and 3.0 (95% CI: 1.0-8.6) for middle cerebral artery. RRs were 0.8 (95% CI: 0.4-1.8) for acetylsalicylic acid use, 0.9 (95% CI: 0.5-1.8) for statin use, 1.4 (95% CI: 0.7-2.8) for hypertension, 0.9 (95% CI: 0.4-1.8) for previous smoking, 0.9 (95% CI: 0.3-2.6) for never smoking, and 1.4 (95% CI: 0.7-2.7) for irregular aneurysm shape. CONCLUSION Approximately one-third of patients had gadolinium-enhancement. Because aneurysm size is the strongest determinant of gadolinium-enhancement and also an established predictor for aneurysm growth and rupture, prospective studies with serial imaging need to investigate if gadolinium-enhancement predicts aneurysm growth and rupture.

scholarly journals Associated intracranial lesions: meningioma and anterior communicating aneurysm

2016 ◽  
Vol 30 (3) ◽  
pp. 360-364
Author(s):  
A. Chiriac ◽  
Georgiana Ion ◽  
Z. Faiyad ◽  
I. Poeata
Keyword(s):  
High Resolution ◽  
Brain Tumors ◽  
Intracranial Aneurysms ◽  
High Resolution Imaging ◽  
Intracranial Lesion ◽  
Good Outcome ◽  
Intracranial Lesions ◽  
Resolution Imaging ◽  
Anterior Communicating Aneurysm ◽  
Rare Situation

Abstract Asymptomatic associated intracranial lesions are more frequently diagnosed with the utilization of high-resolution imaging. The occurrence of brain tumors together with intracranial aneurysms are a very rare situation. This coexistence is still a diagnostic and therapeutic challenge as no consensus concerning imaging that may cover both type of intracranial lesion was established. We report a case of a 62 years old patient with a meningioma and aneurysm treated in one session with good outcome.

Segmentation of aneurysm wall enhancement in evolving unruptured intracranial aneurysms

2021 ◽  
pp. 1-7
Author(s):  
Yukishige Hashimoto ◽  
Toshinori Matsushige ◽  
Reo Kawano ◽  
Koji Shimonaga ◽  
Michitsura Yoshiyama ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Morphological Changes ◽  
Growth Patterns ◽  
Maximum Diameter ◽  
Aneurysm Formation ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Aneurysm Growth ◽  
Wall Imaging

OBJECTIVE Morphological changes in unruptured intracranial aneurysms (UIAs) are an imaging marker of aneurysm instability. Recent studies have indicated the ability of MR vessel wall imaging (VWI) to stratify unstable UIAs based on a correlation with histopathological aneurysm wall inflammation. In the present study the authors investigated the relationships between aneurysm growth patterns and the segmentation of aneurysm wall enhancement (AWE) in VWI. METHODS A total of 120 aneurysms with serial angiography from a follow-up period of at least 2 years (mean 65 months, range 24–215 months) were assessed by VWI. Two readers independently evaluated the patterns of morphological changes (stable, whole sac expansion, and secondary aneurysm formation) and the segmentation of AWE (no, focal, and circumferential AWE). The contrast enhancement ratio of the aneurysm wall versus the pituitary stalk (CRstalk) was calculated for the quantitative assessment of AWE. Statistical analyses were performed to investigate the relationships between AWE patterns and patient baseline profiles, aneurysm characteristics, and morphological modifications. RESULTS Forty-one of 120 UIAs (34%) exhibited aneurysm growth (whole sac expansion in 19 and secondary aneurysm formation in 22). AWE was detected in 35 of 120 UIAs (focal AWE in 25 and circumferential AWE in 10). The maximum diameter of, irregularities in, and morphological modifications in aneurysms were associated with the segmentation of AWE. Focal AWE correlated with secondary aneurysm formation, and circumferential AWE correlated with whole sac expansion. In focal AWE, CRstalk was significantly higher in secondary aneurysm formation than in stable UIAs. UIAs without AWE (categorized as no AWE) correlated with aneurysm stability. CONCLUSIONS The segmentation of AWE was associated with aneurysm growth scenarios and may provide a novel insight into the evaluation of unstable UIAs.

scholarly journals Noninvasive intravital high-resolution imaging of pancreatic neuroendocrine tumours

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mirela Balan ◽  
Marta Trusohamn ◽  
Frank Chenfei Ning ◽  
Stefan Jacob ◽  
Kristian Pietras ◽  
...  
Keyword(s):  
High Resolution ◽  
Real Time ◽  
3D Imaging ◽  
Tumour Growth ◽  
Neuroendocrine Tumours ◽  
Laser Scanning Microscopy ◽  
High Resolution Imaging ◽  
Tumour Angiogenesis ◽  
Pancreatic Neuroendocrine Tumours ◽  
Resolution Imaging

Abstract Preclinical trials of cancer drugs in animal models are important for drug development. The Rip1Tag2 (RT2) transgenic mouse, a model of pancreatic neuroendocrine tumours (PNET), has provided immense knowledge about PNET biology, although tumour progression occurs in a location inaccessible for real-time monitoring. To overcome this hurdle we have developed a novel platform for intravital 3D imaging of RT2 tumours to facilitate real-time studies of cancer progression. Pre-oncogenic islets retrieved from RT2 mice were implanted into the anterior chamber of the eye (ACE) of host mice, where they engrafted on the iris, recruited blood vessels and showed continuous growth. Noninvasive confocal and two-photon laser-scanning microscopy through the transparent cornea facilitated high-resolution imaging of tumour growth and angiogenesis. RT2 tumours in the ACE expanded up to 8-fold in size and shared hallmarks with tumours developing in situ in the pancreas. Genetically encoded fluorescent reporters enabled high-resolution imaging of stromal cells and tumour cell migration. Sunitinib treatment impaired RT2 tumour angiogenesis and growth, while overexpression of the vascular endothelial growth factor (VEGF)-B increased tumour angiogenesis though tumour growth was impaired. In conclusion, we present a novel platform for intravital high-resolution and 3D imaging of PNET biology and cancer drug assessment.

scholarly journals Statin treatment for unruptured intracranial aneurysms study: a study protocol for a double-blind, placebo-controlled trial

2020 ◽  
Vol 5 (4) ◽  
pp. 410-415 ◽  
Author(s):  
Wenqiang Li ◽  
Yisen Zhang ◽  
Zhongbin Tian ◽  
Wei Zhu ◽  
Jian Liu ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Controlled Trial ◽  
Statin Treatment ◽  
Phase Iii ◽  
Related Factors ◽  
Double Blind ◽  
Aneurysm Wall ◽  
Unruptured Intracranial Aneurysms ◽  
Risk Of Rupture ◽  
Be The Change

Background and purposeA large proportion of patients with unruptured intracranial aneurysm (IA) are not suitable for surgical clipping and endovascular treatment. For these patients, anti-inflammatory medications are worth exploring due to inflammation of aneurysmal wall being a major factor in higher risk of rupture. Statin has been proven to reduce inflammation of atherosclerosis and maybe a suitable candidate. This study aimed to evaluate whether atorvastatin will reduce inflammatory of the aneurysm wall measured by the signal index of aneurysm wall enhancement.Methods and analysisThe Statin Treatment for UnruptureD Intracranial anEurysms Study is a single-centre, phase 2, randomised, controlled, double-blind clinical trial. 60 patients with unruptured IAs with aneurysm wall enhancement will be enrolled in Beijing Tiantan Hospital. The patients will be randomised to receive atorvastatin 20 mg or placebo orally per day for 12 months. The primary outcome will be the change in aneurysm wall enhancement measured by the signal index during the 12 months treatment with atorvastatin. The secondary study outcomes will be the change in aneurysm wall enhancement measured by the signal index at 3 months, the changes in aneurysmal morphology and inflammation-related factors (C reactive protein, tumour necrosis factor-α, interleukin-1β and interleukin-6) at 3 and 12 months. This study is the first to explore the role of atorvastatin in reducing inflammation in unruptured IA, which could lay the groundwork for future phase III trial.Ethics and disseminationBeijing Tiantan Hospital’s Ethics committee approved the research and written informed consents would be obtained from all participant or representative included in this study.Trial registration numberNCT04149483

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