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Neulen A, Pantel T, Kosterhon M, Kirschner S, Brockmann MA, Kantelhardt SR, Giese A, Thal SC. A segmentation-based volumetric approach to localize and quantify cerebral vasospasm based on tomographic imaging data. PLoS One 2017; 12:e0172010. [PMID: 28199398 PMCID: PMC5310853 DOI: 10.1371/journal.pone.0172010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 01/30/2017] [Indexed: 12/19/2022] Open
Abstract
Introduction Quantification of cerebral vasospasm after subarachnoid hemorrhage (SAH) is crucial in animal studies as well as clinical routine. We have developed a method for computer-based volumetric assessment of intracranial blood vessels from cross-sectional imaging data. Here we demonstrate the quantification of vasospasm from micro computed tomography (micro-CT) data in a rodent SAH model and the transferability of the volumetric approach to clinical data. Methods We obtained rodent data by performing an ex vivo micro-CT of murine brains after sham surgery or SAH by endovascular filament perforation on day 3 post hemorrhage. Clinical CT angiography (CTA) was performed for diagnostic reasons unrelated to this study. We digitally reconstructed and segmented intracranial vascular trees, followed by calculating volumes of defined vessel segments by standardized protocols using Amira® software. Results SAH animals demonstrated significantly smaller vessel diameters compared with sham (MCA: 134.4±26.9μm vs.165.0±18.7μm, p<0.05). We could highlight this difference by analyzing vessel volumes of a defined MCA-ICA segment (SAH: 0.044±0.017μl vs. sham: 0.07±0.006μl, p<0.001). Analysis of clinical CTA data allowed us to detect and volumetrically quantify vasospasm in a series of 5 SAH patients. Vessel diameters from digital reconstructions correlated well with those measured microscopically (rodent data, correlation coefficient 0.8, p<0.001), or angiographically (clinical data, 0.9, p<0.001). Conclusions Our methodological approach provides accurate anatomical reconstructions of intracranial vessels from cross-sectional imaging data. It allows volumetric assessment of entire vessel segments, hereby highlighting vasospasm-induced changes objectively in a murine SAH model. This method could also be a helpful tool for analysis of clinical CTA.
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Affiliation(s)
- Axel Neulen
- Department of Neurosurgery, University Medical Center of Mainz, Mainz, Germany
- * E-mail: (AN); (SCT)
| | - Tobias Pantel
- Department of Neurosurgery, University Medical Center of Mainz, Mainz, Germany
| | - Michael Kosterhon
- Department of Neurosurgery, University Medical Center of Mainz, Mainz, Germany
| | - Stefanie Kirschner
- Department of Neuroradiology, University Medical Center of Mainz, Mainz, Germany
| | - Marc A. Brockmann
- Department of Neuroradiology, University Medical Center of Mainz, Mainz, Germany
| | - Sven R. Kantelhardt
- Department of Neurosurgery, University Medical Center of Mainz, Mainz, Germany
| | - Alf Giese
- Department of Neurosurgery, University Medical Center of Mainz, Mainz, Germany
| | - Serge C. Thal
- Department of Anesthesiology, University Medical Center of Mainz, Mainz, Germany
- * E-mail: (AN); (SCT)
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Cant J, Palenstijn WJ, Behiels G, Sijbers J. Modeling blurring effects due to continuous gantry rotation: Application to region of interest tomography. Med Phys 2015; 42:2709-17. [DOI: 10.1118/1.4914422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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Keuler A, Taschner C, Brockmann MA, Boll H, Förster K, Lutz L, Herrmann-Frank A, Lelgemann M, Schumacher M. Comparison of high-resolution X-ray and micro-CT for experimental evaluation of intracranial stent prototypes: quality evaluation beyond CE mark. Neuroradiology 2014; 56:315-23. [DOI: 10.1007/s00234-014-1324-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 01/09/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Andreas Keuler
- Department of Neuroradiology, University Medical Center Freiburg, Breisacher Strasse 64, 79106, Freiburg, Germany,
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Comparison of Fenestra LC, ExiTron nano 6000, and ExiTron nano 12000 for micro-CT imaging of liver and spleen in mice. Acad Radiol 2013; 20:1137-43. [PMID: 23931428 DOI: 10.1016/j.acra.2013.06.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/28/2013] [Accepted: 06/03/2013] [Indexed: 12/30/2022]
Abstract
RATIONALE AND OBJECTIVES The purpose of this study was to compare different contrast agents for longitudinal liver and spleen imaging in a mouse model of liver metastasis. MATERIALS AND METHODS Mice developing liver metastases underwent longitudinal micro-computed tomography imaging after injection of Fenestra LC, ExiTron nano 6000, or ExiTron nano 12000. Elimination times and contrast enhancement of liver and spleen were compared. RESULTS For all contrast agents, liver contrast peaked at approximately 4 hours and spleen contrast at 48 hours postinjection. A single dose of 100 μL of ExiTron nano 6000 or 12000 resulted in longstanding enhancement of liver and spleen tissue for longer than 3 weeks, whereas repeated injections of 400 μL of Fenestra LC were required to retain contrast at acceptable levels and allowed imaging of the liver/spleen for up to 2 and 9 days, respectively. CONCLUSION Both ExiTron nano agents provide longer and stronger contrast enhancement of liver and spleen compared to Fenestra LC, and they do so at a 75% lower injection volume in mice.
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Won SY, Schlunk F, Dinkel J, Karatas H, Leung W, Hayakawa K, Lauer A, Steinmetz H, Lo EH, Foerch C, Gupta R. Imaging of contrast medium extravasation in anticoagulation-associated intracerebral hemorrhage with dual-energy computed tomography. Stroke 2013; 44:2883-90. [PMID: 23920016 DOI: 10.1161/strokeaha.113.001224] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Contrast medium extravasation (CE) in intracerebral hemorrhage (ICH) is a marker of ongoing bleeding and a predictor of hematoma expansion. The aims of the study were to establish an ICH model in which CE can be quantified, characterized in ICH during warfarin and dabigatran anticoagulation, and to evaluate effects of prothrombin complex concentrates on CE in warfarin-associated ICH. METHODS CD1-mice were pretreated orally with warfarin, dabigatran, or vehicle. Prothrombin complex concentrates were administered in a subgroup of warfarin-treated mice. ICH was induced by stereotactic injection of collagenase VIIs into the right striatum. Contrast agent (350 μL Isovue 370 mg/mL) was injected intravenously after ICH induction (2-3.5 hours). Thirty minutes later, mice were euthanized, and CE was measured by quantifying the iodine content in the hematoma using dual-energy computed tomography. RESULTS The optimal time point for contrast injection was found to be 3 hours after ICH induction, allowing detection of both an increase and a decrease of CE using dual-energy computed tomography. CE was higher in the warfarin group compared with the controls (P=0.002). There was no significant difference in CE between dabigatran-treated mice and controls. CE was higher in the sham-treated warfarin group than in the prothrombin complex concentrates-treated warfarin group (P<0.001). CONCLUSIONS Dual-energy computed tomography allows quantifying CE, as a marker of ongoing bleeding, in a model of anticoagulation-associated ICH. Dabigatran induces less CE in ICH than warfarin and consequently reduces risks of hematoma expansion. This constitutes a potential safety advantage of dabigatran over warfarin. Nevertheless, in case of warfarin anticoagulation, prothrombin complex concentrates reduce this side effect.
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Affiliation(s)
- Sae-Yeon Won
- From the Department of Neurology, Goethe-University, Frankfurt am Main, Germany (S.-Y.W., F.S., A.L., H.S., C.F.); Neuroprotection Research Laboratory, Massachusetts General Hospital, Charlestown (S.-Y.W., F.S., H.K., W.L., K.H., E.L.); and Department of Radiology, Massachusetts General Hospital, Boston (J.D., R.G.)
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Cardiac Micro-PET-CT. CURRENT CARDIOVASCULAR IMAGING REPORTS 2013. [DOI: 10.1007/s12410-012-9188-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Figueiredo G, Brockmann C, Boll H, Heilmann M, Schambach SJ, Fiebig T, Kramer M, Groden C, Brockmann MA. Comparison of digital subtraction angiography, micro-computed tomography angiography and magnetic resonance angiography in the assessment of the cerebrovascular system in live mice. Clin Neuroradiol 2011; 22:21-8. [PMID: 22109696 DOI: 10.1007/s00062-011-0113-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 11/01/2011] [Indexed: 11/28/2022]
Abstract
PURPOSE Mice are often used as small animal models of brain ischemia, venous thrombosis, or vasospasm. This article aimed at providing an overview of the currently available methodologies for in vivo imaging of the murine cerebrovasculature and comparing the capabilities and limitations of the different methods. METHODS Micro-computed tomography angiography (CTA) was performed during intra-arterial and intravenous administration of a contrast agent bolus. Digital subtraction angiography (DSA) was performed during intra-arterial administration of contrast agent using the micro-CT scanner. Time-of-flight (ToF) magnetic resonance (MR) angiography was performed using a small animal scanner (9.4 T) equipped with a cryogenic transceive quadrature coil. Datasets were compared for scan time, contrast-to-noise ratio (CNR), temporal and spatial resolution, radiation dose, contrast agent dose and detailed recognition of cerebrovascular structures. RESULTS Highest spatial resolution was achieved using micro-CTA (16 x 16 x 16 µm) and DSA (14 x 14 µm). Compared to micro-CTA (20-40 s) and ToF-MRA (57 min), DSA provided highest temporal resolutions (30 fps) allowing analyses of the cerebrovascular blood flow. Highest mean CNR was reached using ToF-MRA (50.7 ± 15.0), while CNR of micro-CTA depended on the intra-arterial (19.0 ± 1.0) and intravenous (1.3 ± 0.4) use of agents. The CNR of DSA was 10.0 ± 1.8. CONCLUSIONS The use of dedicated small animal scanners allows cerebrovascular imaging in live animals as small as mice. As each of the methods analyzed has its advantages and limitations, choosing the best suited imaging modality for a defined question is of great importance. By this means the aforementioned methods offer a great potential for future projects in preclinical cerebrovascular research including ischemic stroke or vasospasm.
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Affiliation(s)
- Giovanna Figueiredo
- Department of Neuroradiology, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, Mannheim, Germany
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Boll H, Nittka S, Doyon F, Neumaier M, Marx A, Kramer M, Groden C, Brockmann MA. Micro-CT based experimental liver imaging using a nanoparticulate contrast agent: a longitudinal study in mice. PLoS One 2011; 6:e25692. [PMID: 21984939 PMCID: PMC3184160 DOI: 10.1371/journal.pone.0025692] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 09/08/2011] [Indexed: 11/24/2022] Open
Abstract
Background Micro-CT imaging of liver disease in mice relies on high soft tissue contrast to detect small lesions like liver metastases. Purpose of this study was to characterize the localization and time course of contrast enhancement of a nanoparticular alkaline earth metal-based contrast agent (VISCOVER ExiTron nano) developed for small animal liver CT imaging. Methodology ExiTron nano 6000 and ExiTron nano 12000, formulated for liver/spleen imaging and angiography, respectively, were intravenously injected in C57BL/6J-mice. The distribution and time course of contrast enhancement were analysed by repeated micro-CT up to 6 months. Finally, mice developing liver metastases after intrasplenic injection of colon carcinoma cells underwent longitudinal micro-CT imaging after a single injection of ExiTron nano. Principal Findings After a single injection of ExiTron nano the contrast of liver and spleen peaked after 4–8 hours, lasted up to several months and was tolerated well by all mice. In addition, strong contrast enhancement of abdominal and mediastinal lymph nodes and the adrenal glands was observed. Within the first two hours after injection, particularly ExiTron nano 12000 provided pronounced contrast for imaging of vascular structures. ExiTron nano facilitated detection of liver metastases and provided sufficient contrast for longitudinal observation of tumor development over weeks. Conclusions The nanoparticulate contrast agents ExiTron nano 6000 and 12000 provide strong contrast of the liver, spleen, lymph nodes and adrenal glands up to weeks, hereby allowing longitudinal monitoring of pathological processes of these organs in small animals, with ExiTron nano 12000 being particularly optimized for angiography due to its very high initial vessel contrast.
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Affiliation(s)
- Hanne Boll
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Stefanie Nittka
- Department of Clinical Chemistry, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Fabian Doyon
- Department of Surgery, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Michael Neumaier
- Department of Clinical Chemistry, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Alexander Marx
- Department of Pathology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Martin Kramer
- Small Animal Clinic, Department of Veterinary Clinical Sciences, Justus-Liebig-University, Giessen, Germany
| | - Christoph Groden
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Marc A. Brockmann
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- * E-mail:
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