Accelerated multi-contrast high isotropic resolution 3D intracranial vessel wall MRI using a tailored k-space undersampling and partially parallel reconstruction strategy

ABSTRACT Intracranial vessel wall imaging plays an increasing role in diagnosing intracranial vascular diseases. With the growing demand and subsequent increased use of this technique in clinical practice, radiologists and neurologists should be aware of the choices in imaging parameters and how they affect image quality, clinical indications, methods of assessment, and limitations in the interpretation of these images. Due to the improvement of the MRI techniques, the possibility of accurate and direct evaluation of the abnormalities in the arterial vascular wall (vessel wall imaging) has evolved, adding substantial data to diagnosis when compared to the indirect evaluation based on conventional flow analyses. Herein, the authors proposed a comprehensive approach of this technique reinforcing appropriated clinical settings to better use intracranial vessel wall imaging.

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Complex wall modeling for hemodynamic simulations of intracranial aneurysms based on histologic images

International Journal of Computer Assisted Radiology and Surgery ◽

10.1007/s11548-021-02334-z ◽

2021 ◽

Vol 16 (4) ◽

pp. 597-607

Author(s):

Annika Niemann ◽

Samuel Voß ◽

Riikka Tulamo ◽

Simon Weigand ◽

Bernhard Preim ◽

...

Keyword(s):

Wall Thickness ◽

Vessel Wall ◽

Intracranial Aneurysms ◽

Geometric Model ◽

Image Data ◽

Outer Wall ◽

3D Models ◽

Patient Specific ◽

Intracranial Vessel ◽

Hemodynamic Simulations

Abstract Purpose For the evaluation and rupture risk assessment of intracranial aneurysms, clinical, morphological and hemodynamic parameters are analyzed. The reliability of intracranial hemodynamic simulations strongly depends on the underlying models. Due to the missing information about the intracranial vessel wall, the patient-specific wall thickness is often neglected as well as the specific physiological and pathological properties of the vessel wall. Methods In this work, we present a model for structural simulations with patient-specific wall thickness including different tissue types based on postmortem histologic image data. Images of histologic 2D slices from intracranial aneurysms were manually segmented in nine tissue classes. After virtual inflation, they were combined into 3D models. This approach yields multiple 3D models of the inner and outer wall and different tissue parts as a prerequisite for subsequent simulations. Result We presented a pipeline to generate 3D models of aneurysms with respect to the different tissue textures occurring in the wall. First experiments show that including the variance of the tissue in the structural simulation affect the simulation result. Especially at the interfaces between neighboring tissue classes, the larger influence of stiffer components on the stability equilibrium became obvious. Conclusion The presented approach enables the creation of a geometric model with differentiated wall tissue. This information can be used for different applications, like hemodynamic simulations, to increase the modeling accuracy.

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Abstract WMP55: Vessel Wall Characteristics using High Resolution Magnetic Resonance Imaging in Reversible Cerebral Vasoconstriction Syndrome and Central Nervous System Vasculitis

Stroke ◽

10.1161/str.44.suppl_1.awmp55 ◽

2013 ◽

Vol 44 (suppl_1) ◽

Author(s):

Russell Cerejo ◽

Seby John ◽

Tariq Hammad ◽

Emmanuel C. Obusez ◽

Rula Hajj-ali ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Central Nervous System ◽

Vessel Wall ◽

Clinical Presentation ◽

Wall Thickening ◽

Resonance Imaging ◽

Cns Vasculitis ◽

Cerebral Vasoconstriction ◽

Intracranial Vessel ◽

Vessel Stenosis

Introduction: Reversible cerebral vasoconstriction syndrome (RCVS) and central nervous system (CNS) vasculitis often have similar initial clinical presentation, laboratory findings and imaging features creating a diagnostic dilemma. High-resolution-3-Tesla Magnetic Resonance Imaging with Gadolinium contrast (HR-MRI) is a non-invasive method to look at intracranial vessel wall characteristics. Methods: A retrospective analysis of all patients with a diagnosis of RCVS or CNS vasculitis that underwent HR-MRI at our institution was performed. Inclusion criteria for RCVS were clinical presentation, no aneurysmal subarachnoid hemorrhage, normal cerebrospinal fluid and reversible multifocal intracranial vessel stenosis whereas criteria for CNS vasculitis were cases with positive brain biopsy or typical clinical presentation, course and laboratory markers with rheumatology and stroke neurology agreement in diagnosis. Demographics, clinical presentation, laboratory testing, imaging studies and outcomes were collected. Results: Eleven patients with RCVS [10 (90.9%) females, mean age 45.2] and 8 with CNS vasculitis [6 primary CNS vasculitis, 6 (75%) males, mean age 43.5] were included in the study. No abnormal vessel wall enhancement or thickening was seen in any of the RCVS patients in areas of vessel stenosis. Six (75%) of CNS vasculitis patients had vessel wall thickening or enhancement (p=0.001 for comparison to RCVS) and the remaining 2 patients had HR-MRI performed 6 and 10 years after diagnosis and chronic treatment. All RCVS patients who had follow up HR-MRI demonstrated resolution of the multifocal stenosis. Two out of 4 CNS vasculitis patients with subsequent HR-MRI imaging had decrease in vessel wall thickening and enhancement after immunosuppressive therapy. Conclusion: In acute stages of presentation, HR-MRI may be useful in differentiating RCVS from CNS vasculitis. It may also be useful in following the disease course to look for resolution of intracranial vessel stenosis in RCVS or treatment response in vasculitis. Further studies are needed to confirm the utility of HR-MRI in diagnosis and disease progression in RCVS and vasculitis.

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