Use of quantitative magnetic resonance angiography in patients with symptomatic intracranial arterial stenosis who undergo stenting: Presentation of three cases

Background and Purpose:— Intracranial arterial stenosis (ICAS) is the predominant cause of ischemic stroke or transient ischemic attack (TIA) in Asia. Change of signal intensities (SI) across an ICAS on magnetic resonance angiography (MRA) may reflect hemodynamic severity of such lesions. Methods:— In-patients with a symptomatic single ICAS of anterior circulation on 3D time-of-flight MRA were recruited. Baseline and 1-year follow-up data were collected. Signal intensity ratio (SIR) was calculated to represent change of SIs across an ICAS on maximum intensity projections: SIR=(mean post-stenotic SI - mean background SI)/(mean pre-stenotic SI - mean background SI). Acute infarct volume was measured on diffusion-weighted images (DWI). Relationships of SIR and baseline characteristics as well as 1-year outcomes were evaluated. Results:— Thirty-six subjects (86.1% males, mean age 55.0 years) were recruited. Overall, mean SIR was 0.84±0.23. Mean SIR of the 23 (63.9%) anatomically severe stenoses was insignificantly lower than the 13 (36.1%) moderate stenoses (0.80±0.23 versus 0.92±0.21, p=0.126). The median baseline infarct volume for the 28 (77.8%) subjects with lesions on DWI was 2.40 cm 3 (IQR 0.80 to 5.78). SIR and acute infarct volume were significantly, linearly and negatively correlated, Spearman correlation coefficient being -0.471 (p=0.011). Two patients (5.6%) had recurrent ischemic strokes at 1-year follow-up. SIR values or acute infarct volumes were unrelated to 1-year outcomes in this initial study. Conclusion:— Change of signal intensity across ICAS on MRA may reflect hemodynamic and functional severity of the lesion. Future studies are warranted to further verify the relationship between this index and prognosis of stroke patients.

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Using the Region of Interest from Time-of-Flight Magnetic Resonance Angiography to Differentiate Between Intracranial Arterial Dissection and True Atherosclerotic Stenosis

Cerebrovascular Diseases ◽

10.1159/000496505 ◽

2019 ◽

Vol 47 (1-2) ◽

pp. 8-14 ◽

Cited By ~ 2

Author(s):

Jung Won Hwang ◽

Jin-Man Jung ◽

Jae Hyung Cha ◽

Il Eok Jung ◽

Moon Ho Park ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Time Of Flight ◽

Region Of Interest ◽

Arterial Stenosis ◽

Arterial Dissection ◽

Intracranial Arterial Stenosis ◽

Tof Mra ◽

Significant Difference ◽

Focal Stenosis

Background: Noncontrast three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) is commonly used to examine intracranial arterial stenosis, although it can be difficult to identify the etiology of the stenosis. Our aim was to determine the effectiveness of 3D TOF MRA in differentiating an intracranial arterial dissection from atherosclerosis. Methods: During 2015–2017, 356 patients had confirmed intracranial arterial stenosis based on high resolution-magnetic resonance imaging. This study ultimately included 51 patients with severe focal stenosis that was caused by dissection and atherosclerosis. We compared the dissection group with the atherosclerotic narrowing group by measuring the region-of-interest (ROI) values 3 mm proximal and 3 mm distal from sites of severe focal stenosis. Results: A significant difference was observed between the median ROI difference values in the dissection group (n = 18) and the atherosclerosis group (n = 33; 35.6 [20.9–78.4] vs. 165.5 [99.8–328.5]; p < 0.001). A receiver operating characteristic curve was prepared to distinguish between dissection and atherosclerosis using the ROI difference values. The area under the curve was 0.919 (sensitivity 75.8%, specificity 94.4%). The optimal cutoff value for using ROI to distinguish between dissection and atherosclerosis was found to be 99.0 based on the Youden’s index. Conclusion: The ROI difference value from 3D TOF MRA could help distinguish between dissection and atherosclerosis. If the ROI difference value from 3D TOF MRA is small (< 99.0), detailed testing should be performed to identify dissection.

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Evaluation of extracranial–intracranial bypass using quantitative magnetic resonance angiography

Yearbook of Neurology and Neurosurgery ◽

10.1016/s0513-5117(08)79156-7 ◽

2008 ◽

Vol 2008 ◽

pp. 226-227

Author(s):

D.H. Kim

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Quantitative Magnetic Resonance

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Validation of cerebral arteriovenous malformation hemodynamics assessed by DSA using quantitative magnetic resonance angiography: preliminary study

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2017-012991 ◽

2017 ◽

Vol 10 (2) ◽

pp. 156-161 ◽

Cited By ~ 19

Author(s):

Sophia F Shakur ◽

Denise Brunozzi ◽

Ahmed E Hussein ◽

Andreas Linninger ◽

Chih-Yang Hsu ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Transit Time ◽

Internal Carotid ◽

Flow Measurements ◽

Quantitative Magnetic Resonance ◽

Transit Times ◽

Before And After ◽

Preliminary Study ◽

The Difference

BackgroundThe hemodynamic evaluation of cerebral arteriovenous malformations (AVMs) using DSA has not been validated against true flow measurements.ObjectiveTo validate AVM hemodynamics assessed by DSA using quantitative magnetic resonance angiography (QMRA).Materials and methodsPatients seen at our institution between 2007 and 2016 with a supratentorial AVM and DSA and QMRA obtained before any treatment were retrospectively reviewed. DSA assessment of AVM flow comprised AVM arterial-to-venous time (A-Vt) and iFlow transit time. A-Vt was defined as the difference between peak contrast intensity in the cavernous internal carotid artery and peak contrast intensity in the draining vein. iFlow transit times were determined using syngo iFlow software. A-Vt and iFlow transit times were correlated with total AVM flow measured using QMRA and AVM angioarchitectural and clinical features.Results33 patients (mean age 33 years) were included. Nine patients presented with hemorrhage. Mean AVM volume was 9.8 mL (range 0.3–57.7 mL). Both A-Vt (r=−0.47, p=0.01) and iFlow (r=−0.44, p=0.01) correlated significantly with total AVM flow. iFlow transit time was significantly shorter in patients who presented with seizure but A-Vt and iFlow did not vary with other AVM angioarchitectural features such as venous stenosis or hemorrhagic presentation.ConclusionsA-Vt and iFlow transit times on DSA correlate with cerebral AVM flow measured using QMRA. Thus, these parameters may be used to indirectly estimate AVM flow before and after embolization during angiography in real time.

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Leptomeningeal Collateral Volume Flow Assessed by Quantitative Magnetic Resonance Angiography in Large-Vessel Cerebrovascular Disease

Journal of Neuroimaging ◽

10.1111/j.1552-6569.2008.00249.x ◽

2009 ◽

Vol 19 (1) ◽

pp. 27-30 ◽

Cited By ~ 23

Author(s):

Sean Ruland ◽

Aiesha Ahmed ◽

Kurian Thomas ◽

Meide Zhao ◽

Sepideh Amin-Hanjani ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Cerebrovascular Disease ◽

Volume Flow ◽

Large Vessel ◽

Quantitative Magnetic Resonance

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High-resolution Magnetic Resonance Vessel Wall Imaging for Intracranial Arterial Stenosis

Chinese Medical Journal ◽

10.4103/0366-6999.182826 ◽

2016 ◽

Vol 129 (11) ◽

pp. 1363-1370 ◽

Cited By ~ 18

Author(s):

Xian-Jin Zhu ◽

Wu Wang ◽

Zun-Jing Liu

Keyword(s):

Magnetic Resonance ◽

High Resolution ◽

Vessel Wall ◽

Vessel Wall Imaging ◽

Arterial Stenosis ◽

Intracranial Arterial Stenosis ◽

Wall Imaging

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Combined Direct and Indirect Bypass for Moyamoya

Neurosurgery ◽

10.1227/neu.0000000000000139 ◽

2013 ◽

Vol 73 (6) ◽

pp. 962-968 ◽

Cited By ~ 42

Author(s):

Sepideh Amin-Hanjani ◽

Amritha Singh ◽

Hashem Rifai ◽

Keith R. Thulborn ◽

Ali Alaraj ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Superficial Temporal Artery ◽

Temporal Artery ◽

Reciprocal Relationship ◽

Bypass Flow ◽

Similar Time ◽

Quantitative Magnetic Resonance ◽

Small Cohort ◽

Direct Bypass

Abstract BACKGROUND: The optimal revascularization strategy for symptomatic adult moyamoya remains controversial. Whereas direct bypass offers immediate revascularization, indirect bypass can effectively induce collaterals over time. OBJECTIVE: Using angiography and quantitative magnetic resonance angiography, we examined the relative contributions of direct and indirect bypass in moyamoya patients after combined direct superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass and indirect encephaloduroarteriosynangiosis (EDAS). METHODS: A retrospective review of moyamoya patients undergoing combined STA-MCA bypass and EDAS was conducted, excluding pediatric patients and hemorrhagic presentation. Patients with quantitative magnetic resonance angiography measurements of the direct bypass immediately and > 6 months postoperatively were included. Angiographic follow-up, when available, was used to assess EDAS collaterals at similar time intervals. RESULTS: Of 16 hemispheres in 13 patients, 11 (69%) demonstrated a significant (> 50%) decline in direct bypass flow at > 6 months compared with baseline, averaging a drop from 99 ± 35 to12 ± 7 mL/min. Conversely, angiography in these hemispheres demonstrated prominent indirect collaterals, in concert with shrinkage of the STA graft. Decline in flow was apparent at a median of 9 months but was evident as early as 2 to 3 months. CONCLUSION: In this small cohort, a reciprocal relationship between direct STA bypass flow and indirect EDAS collaterals frequently occurred. This substantiates the notion that combined direct/indirect bypass can provide temporally complementary revascularization.

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