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Evaluation of Ischemic Penumbra in Stroke Patients Based on Deep Learning and Multimodal CT. JOURNAL OF HEALTHCARE ENGINEERING 2021. [DOI: 10.1155/2021/3215107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In order to investigate the value of multimodal CT for quantitative assessment of collateral circulation, ischemic semidark zone, core infarct volume in patients with acute ischemic stroke (AIS), and prognosis assessment in intravenous thrombolytic therapy, segmentation model which is based on the self-attention mechanism is prone to generate attention coefficient maps with incorrect regions of interest. Moreover, the stroke lesion is not clearly characterized, and lesion boundary is poorly differentiated from normal brain tissue, thus affecting the segmentation performance. To address this problem, a primary and secondary path attention compensation network structure is proposed, which is based on the improved global attention upsampling U-Net model. The main path network is responsible for performing accurate lesion segmentation and outputting segmentation results. Likewise, the auxiliary path network generates loose auxiliary attention compensation coefficients, which compensate for possible attention coefficient errors in the main path network. Two hybrid loss functions are proposed to realize the respective functions of main and auxiliary path networks. It is experimentally demonstrated that both the improved global attention upsampling U-Net and the proposed primary and secondary path attention compensation networks show significant improvement in segmentation performance. Moreover, patients with good collateral circulation have a small final infarct area volume and a good clinical prognosis after intravenous thrombolysis. Quantitative assessment of collateral circulation and ischemic semidark zone by multimodal CT can better predict the clinical prognosis of intravenous thrombolysis.
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Statement of ESMINT and ESNR regarding recent trials evaluating the endovascular treatment at the acute stage of ischemic stroke. Neuroradiology 2014; 55:1313-8. [PMID: 23959060 DOI: 10.1007/s00234-013-1249-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 07/17/2013] [Indexed: 01/19/2023]
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Grossman AW, Broderick JP. Advances and challenges in treatment and prevention of ischemic stroke. Ann Neurol 2013; 74:363-72. [PMID: 23929628 DOI: 10.1002/ana.23993] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/07/2013] [Accepted: 07/29/2013] [Indexed: 11/05/2022]
Abstract
We review recent advances in the treatment and prevention of acute ischemic stroke, including the current state of endovascular therapy, in light of 5 randomized controlled trials published this past year. Although no benefit of endovascular therapy over intravenous (IV) recombinant tissue plasminogen activator (rt-PA) has been demonstrated, endovascular therapy is an appropriate treatment for acute ischemic stroke patients within the t-PA window who are ineligible for IV t-PA but have a large vascular occlusion. These trials reveal promises and current limitations of endovascular therapy, and comparison of reperfusion therapies remains an important area of research. One common theme is the strong association between a faster time to reperfusion, improved outcome, and reduced mortality. Primary and secondary stroke prevention trials emphasize the importance of aggressive management of medical risk factors as part of any preventative strategy. New oral anticoagulants, for example, offer cost-effective risk reduction in patients with atrial fibrillation, and may represent an opportunity for those with cryptogenic stroke. We highlight areas of unmet need and promising research in stroke, including the need to deliver proven therapies to more patients, and the need to recruit patients into clinical trials that better define the role of endovascular and other stroke therapies. Finally, improvement in strategies to recover speech, cognition, and motor function has the potential to benefit far more stroke patients than any acute stroke therapy, and represents the greatest opportunity for research in the coming century.
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Affiliation(s)
- Aaron W Grossman
- Department of Neurology, University of Cincinnati Neuroscience Institute, University of Cincinnati Academic Health Center, Cincinnati, OH
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Simon S, Grey CP, Massenzo T, Simpson DG, Longest PW. Exploring the efficacy of cyclic vs static aspiration in a cerebral thrombectomy model: an initial proof of concept study. J Neurointerv Surg 2013; 6:677-83. [PMID: 24235098 DOI: 10.1136/neurintsurg-2013-010941] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND PURPOSE Current technology for endovascular thrombectomy in ischemic stroke utilizes static loading and is successful in approximately 85% of cases. Existing technology uses either static suction (applied via a continuous pump or syringe) or flow arrest with a proximal balloon. In this paper we evaluate the potential of cyclic loading in aspiration thrombectomy. METHODS In order to evaluate the efficacy of cyclic aspiration, a model was created using a Penumbra aspiration system, three-way valve and Penumbra 5Max catheter. Synthetic clots were aspirated at different frequencies and using different aspiration mediums. Success or failure of clot removal and time were recorded. All statistical analyses were based on either a one-way or two-way analysis of variance, Holm-Sidak pairwise multiple comparison procedure (α=0.05). RESULTS Cyclic aspiration outperformed static aspiration in overall clot removal and removal speed (p<0.001). Within cyclic aspiration, Max Hz frequencies (∼6.3 Hz) cleared clots faster than 1 Hz (p<0.001) and 2 Hz (p=0.024). Loading cycle dynamics (specific pressure waveforms) affected speed and overall clearance (p<0.001). Water as the aspiration medium was more effective at clearing clots than air (p=0.019). CONCLUSIONS Cyclic aspiration significantly outperformed static aspiration in speed and overall clearance of synthetic clots in our experimental model. Within cyclic aspiration, efficacy is improved by increasing cycle frequency, utilizing specific pressure cycle waveforms and using water rather than air as the aspiration medium. These findings provide a starting point for altering existing thrombectomy technology or perhaps the development of new technologies with higher recanalization rates.
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Affiliation(s)
- Scott Simon
- Department of Neurosurgery, Pennsylvania State University, Hershey, Pennsylvania, USA
| | - Casey Paul Grey
- Department of Neurosurgery, Pennsylvania State University, Hershey, Pennsylvania, USA
| | - Trisha Massenzo
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
| | - David G Simpson
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
| | - P Worth Longest
- Department of Mechanical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA Department of Pharmaceutics, Virginia Commonwealth University, Richmond, Virginia, USA
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Eesa M, Burns PA, Almekhlafi MA, Menon BK, Wong JH, Mitha A, Morrish W, Demchuk AM, Goyal M. Mechanical thrombectomy with the Solitaire stent: is there a learning curve in achieving rapid recanalization times? J Neurointerv Surg 2013; 6:649-51. [PMID: 24151114 DOI: 10.1136/neurintsurg-2013-010906] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
METHODS In acute ischemic stroke, good outcome following successful recanalization is time dependent. In patients undergoing endovascular therapy at our institution, recanalization times with the Solitaire stent were retrospectively evaluated to assess for the presence of a learning curve in achieving rapid recanalization. METHODS We reviewed patients who presented to our stroke center and achieved successful recanalization with the Solitaire stent exclusively. Time intervals were calculated (CT to angiography arrival, angiography arrival to groin puncture, groin puncture to first deployment, and deployment to recanalization) from time stamped images and angiography records. Patients were divided into three sequential groups, with overall CT to recanalization time and subdivided time intervals compared. RESULTS 83 patients were treated with the Solitaire stent from May 2009 to February 2012. Recanalization (Thrombolyis in Cerebral Infarction score 2A) occurred in 75 (90.4%) patients. CT to recanalization demonstrated significant improvement over time, which was greatest between the first 25 and the most recent 25 cases (161-94 min; p<0.01). The maximal contribution to this was from improvements in first stent deployment to recanalization time (p=0.001 between the first and third groups), with modest contributions from moving patients from CT to the angiography suite faster (p=0.02 between the first and third groups) and from groin puncture to first stent deployment (p=0.02 between the first and third groups). CONCLUSIONS There is a learning curve involved in the efficient use of the Solitaire stent in endovascular acute stroke therapy. Along with improvements in patient transfer to angiography and improved efficiency with intracranial access, mastering this device contributed significantly towards reducing recanalization times.
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Affiliation(s)
- M Eesa
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - P A Burns
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - M A Almekhlafi
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada Department of Internal Medicine, King Abdulaziz University, Jeddah, Western, Saudi Arabia
| | - B K Menon
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - J H Wong
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - A Mitha
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - W Morrish
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - A M Demchuk
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - M Goyal
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
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