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Research paper thumbnail of What constitutes the M1 segment of the middle cerebral artery?

Journal of NeuroInterventional Surgery, 2016

Intravenous tissue plasminogen activator has limited efficacy in fibrinolysis of large proximal i... more Intravenous tissue plasminogen activator has limited efficacy in fibrinolysis of large proximal intracranial thrombi. Thus, recent endovascular acute stroke trials restricted their selection criteria to patients with proximal occlusions in the anterior circulation. Although the terminal internal carotid artery occlusion is relatively easy to identify, there is often a debate as to what constitutes a proximal (involving the M1 segment) versus a distal (involving the M2 segment and beyond) middle cerebral artery occlusion. In light of overwhelming evidence demonstrating superiority of endovascular treatment in patients with proximal occlusion, this distinction has significant practical implications in patient selection. Here we present a brief review of the proximal (M1) segment of the middle cerebral artery anatomy and provide practical methods to recognize and separate the M1 and M2 segments. In keeping with the belief that CT angiography (CTA) (preferably multiphase CTA) is the ideal screening test for patients with emergent large vessel occlusion, we have provided tips for expeditious and accurate vascular imaging interpretation.

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Research paper thumbnail of Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke

Radiology, Jan 29, 2015

Purpose To describe the use of an imaging selection tool, multiphase computed tomographic (CT) an... more Purpose To describe the use of an imaging selection tool, multiphase computed tomographic (CT) angiography, in patients with acute ischemic stroke (AIS) and to demonstrate its interrater reliability and ability to help determine clinical outcome. Materials and Methods The local ethics board approved this study. Data are from the pilot phase of PRoveIT, a prospective observational study analyzing utility of multimodal imaging in the triage of patients with AIS. Patients underwent baseline unenhanced CT, single-phase CT angiography of the head and neck, multiphase CT angiography, and perfusion CT. Multiphase CT angiography generates time-resolved images of pial arteries. Pial arterial filling was scored on a six-point ordinal scale, and interrater reliability was tested. Clinical outcomes included a 50% or greater decrease in National Institutes of Health Stroke Scale (NIHSS) over 24 hours and 90-day modified Rankin Scale (mRS) score of 0-2. The ability to predict clinical outcomes was compared between single-phase CT angiography, multiphase CT angiography, and perfusion CT by using receiver operating curve analysis, Akaike information criterion (AIC), and Bayesian information criterion (BIC). Results A total of 147 patients were included. Interrater reliability for multiphase CT angiography is excellent (n = 30, κ = 0.81, P < .001). At receiver operating characteristic curve analysis, the ability to predict clinical outcome is modest (C statistic = 0.56, 95% confidence interval [CI]: 0.52, 0.63 for ≥50% decrease in NIHSS over 24 hours; C statistic = 0.6, 95% CI: 0.53, 0.68 for 90-day mRS score of 0-2) but better than that of models using single-phase CT angiography and perfusion CT (P < .05 overall). With AIC and BIC, models that use multiphase CT angiography are better than models that use single-phase CT angiography and perfusion CT for a decrease of 50% or more in NIHSS over 24 hours (AIC = 166, BIC = 171.7; values were lowest for multiphase CT angiography) and a 90-day mRS score of 0-2 (AIC = 132.1, BIC = 137.4; values were lowest for multiphase CT angiography). Conclusion Multiphase CT angiography is a reliable tool for imaging selection in patients with AIS. (©) RSNA, 2015 Online supplemental material is available for this article.

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Research paper thumbnail of Thrombus Characteristics Are Related to Collaterals and Angioarchitecture in Acute Stroke

The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques

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Research paper thumbnail of Optimizing Acute Stroke Imaging for Maximizing Information and Minimizing Acquisition, Post Processing and Interpretation Times: Analysis of Data From PROVE-IT, a Prospective Imaging Cohort Study

Stroke

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Research paper thumbnail of Thrombus Characteristics Are Related to Collaterals and Angioarchitecture in Acute Stroke

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques, 2015

BackgroundWe have theorized that clots with stasis are longer. We therefore explored the relation... more BackgroundWe have theorized that clots with stasis are longer. We therefore explored the relationship between thrombus imaging characteristics on noncontrast computed tomography (NCCT) and magnetic resonance imaging (MRI) with clot length and pial collaterals on baseline computed tomography angiography (CTA).MethodsProspective study of acute ischemic stroke patients (2005-2009) from Keimyung University. Patients with known stroke symptom onset time, baseline CTA, MRI, and with M1-Middle Cerebral Artery (MCA)±intracranial internal carotid artery (ICA) occlusions were included. Clot length and pial collaterals were measured on baseline CTA.ResultsA total of 104 patients (mean age 65.1±12.28 years, 56.7% male, median baseline National Institutes of Health Stroke Scale 13) with intracranial ICA + MCA (n=50) or isolated M1-MCA (n=54) occlusions were included. Hyperdense sign on NCCT had a median clot length of 42.3 mm versus 29.5 mm when hyperdense negative (p=0.02). Clots showing bloomi...

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Research paper thumbnail of Occult anterograde flow in acute ishemic stroke: An under-recognized but crucial predictor of early recanalization with IV TPA using standard ct perfusion T0 maps

International Journal of Stroke

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Research paper thumbnail of Aneurysmal subarachnoid hemorrhage affects the younger age groups in a Saudi academic center

Annals of Saudi medicine

The epidemiology, clinical characteristics, and risk factors of aneurysmal subarachnoid hemorrhag... more The epidemiology, clinical characteristics, and risk factors of aneurysmal subarachnoid hemorrhage (aSAH) in Saudi Arabia are still largely unknown. This retrospective cohort study was aimed to determine these features of the disease. A retrospective cohort review was performed on all patients with aSAH who were treated and followed at King Abdulaziz University Hospital between July 2000 and December 2013. A quantitative methodology was used and data were collected on patients' age, gender, nationality, time to hospital presentation, clinical presentation, aneurysm characteristics, treatment, complications, and outcome. A total of 41 patients with aSAH were included with a mean age of 43.2 (11.5) years; and males comprised 34.1%. Smoking and hypertension were the most common risk factors. Eight patients had known risk factors for aSAH, and were diagnosed using CT scans. An unfavorable outcome was associated with the pres.ence of vasospasm (P < .001), cerebral edema (P=.001), ...

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Research paper thumbnail of Figure - med res

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Research paper thumbnail of Figure 2

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Research paper thumbnail of Predictors of poor leptomeningeal collateral status in acute ischemic strokes: analysis of data from the Keimyung stroke registry

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Research paper thumbnail of Role of biological markers in predicting findings of multimodal thrombus imaging: implications for aetiology and recanalization

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Research paper thumbnail of Predictors of new lesions on diffusion weighted imaging post carotid stenting a prospective study using procedural trans cranial doppler monitoring

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Research paper thumbnail of Predictors of readmission within the first year following carotid revascularization

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Research paper thumbnail of Imaging-to-Stent deployment Time Interval Is Shorter during Daytime Hours' Vs. Evening Times in Endovascular Therapy for Acute Ischemic Stroke

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Research paper thumbnail of Not All Successful Reperfusion PatiNot All Successful Reperfusion Patients Are Equal: The Need for a TICI2c Scoreents Are Equal: The Need for a TICI2c Score

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Research paper thumbnail of FLAIR Hyperintense Vessel Sign on MRI brain (HVS) Does Not Predict Any Intracranial Hemorrhage or Symptomatic Hemorrhage (sICH) in Acute Strokes with Proximal Vessel Occlusions Treated with Intravenous or Intra-Arterial Lytic/Mechanical Therapy

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Research paper thumbnail of The Study of Hyperintense Flair Vessel (HVS) Sign Reversal On FLAIR MRI In Acute Strokes with Proximal Vessel Occlusions, Does It Make Us Any Wise?

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Research paper thumbnail of Dural Arteriovenous Fistula Treated by Combined Surgical/Endovascular Approach

ABSTRACT Dural arteriovenous fistulas (dAVFs) are unusual vascular lesions that may form because ... more ABSTRACT Dural arteriovenous fistulas (dAVFs) are unusual vascular lesions that may form because of trauma or sinus thrombosis, but are idiopathic in most cases [1]. Connections between the dural artery and the cortical veins result in the veins being exposed to high pressures, leading to venous hypertension and subarachnoid hemorrhage [2]. Patients may present with pulsatile tinnitus (or pulse-synchronous cephalic bruit), non-specific headaches, vision loss or mental status change [3]. One or several major arteries can supply a dAVF, including the vertebral, basilar, and external (ECA) or internal carotid arteries (ICA) through their dural branches [2]. Given the high risk of bleeding in dAVFs with cortical venous hypertension, treatment of such lesions is indicated. This can be achieved via endovascular occlusion of the fistulous pouch or via open microsurgical disconnection.

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Research paper thumbnail of Do arch and carotid characteristics on CT angiography predict delay in puncture to device deployment time in acute ischemic strokes?

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Research paper thumbnail of CT perfusion thresholds to separate acute infarct core from penumbra using optimized imaging and advanced postprocessing

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Research paper thumbnail of What constitutes the M1 segment of the middle cerebral artery?

Journal of NeuroInterventional Surgery, 2016

Intravenous tissue plasminogen activator has limited efficacy in fibrinolysis of large proximal i... more Intravenous tissue plasminogen activator has limited efficacy in fibrinolysis of large proximal intracranial thrombi. Thus, recent endovascular acute stroke trials restricted their selection criteria to patients with proximal occlusions in the anterior circulation. Although the terminal internal carotid artery occlusion is relatively easy to identify, there is often a debate as to what constitutes a proximal (involving the M1 segment) versus a distal (involving the M2 segment and beyond) middle cerebral artery occlusion. In light of overwhelming evidence demonstrating superiority of endovascular treatment in patients with proximal occlusion, this distinction has significant practical implications in patient selection. Here we present a brief review of the proximal (M1) segment of the middle cerebral artery anatomy and provide practical methods to recognize and separate the M1 and M2 segments. In keeping with the belief that CT angiography (CTA) (preferably multiphase CTA) is the ideal screening test for patients with emergent large vessel occlusion, we have provided tips for expeditious and accurate vascular imaging interpretation.

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Research paper thumbnail of Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke

Radiology, Jan 29, 2015

Purpose To describe the use of an imaging selection tool, multiphase computed tomographic (CT) an... more Purpose To describe the use of an imaging selection tool, multiphase computed tomographic (CT) angiography, in patients with acute ischemic stroke (AIS) and to demonstrate its interrater reliability and ability to help determine clinical outcome. Materials and Methods The local ethics board approved this study. Data are from the pilot phase of PRoveIT, a prospective observational study analyzing utility of multimodal imaging in the triage of patients with AIS. Patients underwent baseline unenhanced CT, single-phase CT angiography of the head and neck, multiphase CT angiography, and perfusion CT. Multiphase CT angiography generates time-resolved images of pial arteries. Pial arterial filling was scored on a six-point ordinal scale, and interrater reliability was tested. Clinical outcomes included a 50% or greater decrease in National Institutes of Health Stroke Scale (NIHSS) over 24 hours and 90-day modified Rankin Scale (mRS) score of 0-2. The ability to predict clinical outcomes was compared between single-phase CT angiography, multiphase CT angiography, and perfusion CT by using receiver operating curve analysis, Akaike information criterion (AIC), and Bayesian information criterion (BIC). Results A total of 147 patients were included. Interrater reliability for multiphase CT angiography is excellent (n = 30, κ = 0.81, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). At receiver operating characteristic curve analysis, the ability to predict clinical outcome is modest (C statistic = 0.56, 95% confidence interval [CI]: 0.52, 0.63 for ≥50% decrease in NIHSS over 24 hours; C statistic = 0.6, 95% CI: 0.53, 0.68 for 90-day mRS score of 0-2) but better than that of models using single-phase CT angiography and perfusion CT (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .05 overall). With AIC and BIC, models that use multiphase CT angiography are better than models that use single-phase CT angiography and perfusion CT for a decrease of 50% or more in NIHSS over 24 hours (AIC = 166, BIC = 171.7; values were lowest for multiphase CT angiography) and a 90-day mRS score of 0-2 (AIC = 132.1, BIC = 137.4; values were lowest for multiphase CT angiography). Conclusion Multiphase CT angiography is a reliable tool for imaging selection in patients with AIS. (©) RSNA, 2015 Online supplemental material is available for this article.

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Research paper thumbnail of Thrombus Characteristics Are Related to Collaterals and Angioarchitecture in Acute Stroke

The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques

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Research paper thumbnail of Optimizing Acute Stroke Imaging for Maximizing Information and Minimizing Acquisition, Post Processing and Interpretation Times: Analysis of Data From PROVE-IT, a Prospective Imaging Cohort Study

Stroke

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Research paper thumbnail of Thrombus Characteristics Are Related to Collaterals and Angioarchitecture in Acute Stroke

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques, 2015

BackgroundWe have theorized that clots with stasis are longer. We therefore explored the relation... more BackgroundWe have theorized that clots with stasis are longer. We therefore explored the relationship between thrombus imaging characteristics on noncontrast computed tomography (NCCT) and magnetic resonance imaging (MRI) with clot length and pial collaterals on baseline computed tomography angiography (CTA).MethodsProspective study of acute ischemic stroke patients (2005-2009) from Keimyung University. Patients with known stroke symptom onset time, baseline CTA, MRI, and with M1-Middle Cerebral Artery (MCA)±intracranial internal carotid artery (ICA) occlusions were included. Clot length and pial collaterals were measured on baseline CTA.ResultsA total of 104 patients (mean age 65.1±12.28 years, 56.7% male, median baseline National Institutes of Health Stroke Scale 13) with intracranial ICA + MCA (n=50) or isolated M1-MCA (n=54) occlusions were included. Hyperdense sign on NCCT had a median clot length of 42.3 mm versus 29.5 mm when hyperdense negative (p=0.02). Clots showing bloomi...

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Research paper thumbnail of Occult anterograde flow in acute ishemic stroke: An under-recognized but crucial predictor of early recanalization with IV TPA using standard ct perfusion T0 maps

International Journal of Stroke

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Research paper thumbnail of Aneurysmal subarachnoid hemorrhage affects the younger age groups in a Saudi academic center

Annals of Saudi medicine

The epidemiology, clinical characteristics, and risk factors of aneurysmal subarachnoid hemorrhag... more The epidemiology, clinical characteristics, and risk factors of aneurysmal subarachnoid hemorrhage (aSAH) in Saudi Arabia are still largely unknown. This retrospective cohort study was aimed to determine these features of the disease. A retrospective cohort review was performed on all patients with aSAH who were treated and followed at King Abdulaziz University Hospital between July 2000 and December 2013. A quantitative methodology was used and data were collected on patients' age, gender, nationality, time to hospital presentation, clinical presentation, aneurysm characteristics, treatment, complications, and outcome. A total of 41 patients with aSAH were included with a mean age of 43.2 (11.5) years; and males comprised 34.1%. Smoking and hypertension were the most common risk factors. Eight patients had known risk factors for aSAH, and were diagnosed using CT scans. An unfavorable outcome was associated with the pres.ence of vasospasm (P < .001), cerebral edema (P=.001), ...

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Research paper thumbnail of Figure - med res

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Research paper thumbnail of Figure 2

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Research paper thumbnail of Predictors of poor leptomeningeal collateral status in acute ischemic strokes: analysis of data from the Keimyung stroke registry

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Role of biological markers in predicting findings of multimodal thrombus imaging: implications for aetiology and recanalization

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Predictors of new lesions on diffusion weighted imaging post carotid stenting a prospective study using procedural trans cranial doppler monitoring

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Predictors of readmission within the first year following carotid revascularization

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Imaging-to-Stent deployment Time Interval Is Shorter during Daytime Hours' Vs. Evening Times in Endovascular Therapy for Acute Ischemic Stroke

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Not All Successful Reperfusion PatiNot All Successful Reperfusion Patients Are Equal: The Need for a TICI2c Scoreents Are Equal: The Need for a TICI2c Score

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Research paper thumbnail of FLAIR Hyperintense Vessel Sign on MRI brain (HVS) Does Not Predict Any Intracranial Hemorrhage or Symptomatic Hemorrhage (sICH) in Acute Strokes with Proximal Vessel Occlusions Treated with Intravenous or Intra-Arterial Lytic/Mechanical Therapy

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Research paper thumbnail of The Study of Hyperintense Flair Vessel (HVS) Sign Reversal On FLAIR MRI In Acute Strokes with Proximal Vessel Occlusions, Does It Make Us Any Wise?

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Research paper thumbnail of Dural Arteriovenous Fistula Treated by Combined Surgical/Endovascular Approach

ABSTRACT Dural arteriovenous fistulas (dAVFs) are unusual vascular lesions that may form because ... more ABSTRACT Dural arteriovenous fistulas (dAVFs) are unusual vascular lesions that may form because of trauma or sinus thrombosis, but are idiopathic in most cases [1]. Connections between the dural artery and the cortical veins result in the veins being exposed to high pressures, leading to venous hypertension and subarachnoid hemorrhage [2]. Patients may present with pulsatile tinnitus (or pulse-synchronous cephalic bruit), non-specific headaches, vision loss or mental status change [3]. One or several major arteries can supply a dAVF, including the vertebral, basilar, and external (ECA) or internal carotid arteries (ICA) through their dural branches [2]. Given the high risk of bleeding in dAVFs with cortical venous hypertension, treatment of such lesions is indicated. This can be achieved via endovascular occlusion of the fistulous pouch or via open microsurgical disconnection.

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Research paper thumbnail of Do arch and carotid characteristics on CT angiography predict delay in puncture to device deployment time in acute ischemic strokes?

Bookmarks Related papers MentionsView impact

Research paper thumbnail of CT perfusion thresholds to separate acute infarct core from penumbra using optimized imaging and advanced postprocessing

Bookmarks Related papers MentionsView impact