Abstract 158: Magnetic Resonance Angiography Signal Intensity as a Marker of Hemodynamic Impairment in Intracranial Arterial Stenosis

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Xinyi Leng ◽  
Ka Sing Wong ◽  
Yannie Soo ◽  
Thomas Leung ◽  
Xinying Zou ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Signal Intensity ◽  
Infarct Volume ◽  
Arterial Stenosis ◽  
Intracranial Arterial Stenosis ◽  
Anterior Circulation ◽  
Diffusion Weighted Images ◽  
Acute Infarct

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.

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

2019 ◽  
Vol 47 (1-2) ◽  
pp. 8-14 ◽  
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.

Decrease in Secondary Neck Vessels in Multiple Sclerosis: A 5-year Longitudinal Magnetic Resonance Angiography Study

2019 ◽  
Vol 16 (3) ◽  
pp. 215-223 ◽  
Author(s):  
Dejan Jakimovski ◽  
Matthew Topolski ◽  
Kana Kimura ◽  
Virja Pandya ◽  
Bianca Weinstock-Guttman ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Longitudinal Change ◽  
Repeated Measure ◽  
Cross Sectional ◽  
False Discovery ◽  
The Common ◽  
Neck Vessels

Background: Studies have previously shown greater arterial and venous extracranial vascular changes in persons with multiple sclerosis (PwMS) when compared to healthy controls (HCs). Objectives: To determine the change in the number and size of secondary neck vessels in PwMS and HCs over a 5-year follow-up period. Methods: Both at baseline and follow-up, 83 PwMS and 25 HCs underwent magnetic resonance angiography (MRA) imaging and analysis. The number and cross-sectional area (CSA) of all secondary neck vessels (excluding the common/internal carotid, vertebral artery, and internal jugular vein) measured at levels from C2-T1 were determined by semi-automated edge detection/ contouring software. The longitudinal change in the number and CSA of the secondary neck vessels from the PwMS and HCs were analyzed by non-parametric Wilcoxon repeated measure. Benjamini-Hochberg procedure adjusted for false discovery rate (FDR). Results: For over 5 years, PwMS demonstrated a consistent longitudinal decrease in both the number of secondary neck vessels (Z-change between -3.3 and -5.4, q=0.001) and their CSA (Zchange between -2.9 and -5.2, q=0.004). On the contrary, the HCs did not demonstrate a significant longitudinal change in secondary neck vessels over the follow-up period. Due to the longitudinal decrease, the PwMS showed a lower number of secondary neck vessels when compared to HCs measured at follow-up (p<0.029, except for C4 with trending p=0.071). The PwMS changes were also corroborated within each MS phenotype. Conclusion: PwMS demonstrate a significant mid-term decrease in the number and the size of the secondary neck vessels. The clinical relevance of these findings and the effect on intracranial blood flow are currently unknown.

Black blood magnetic resonance angiography with Dy-DTPA polymer: Effect on arterial intraluminal signal intensity, lumen diameter, and wall thickness

1998 ◽  
Vol 8 (5) ◽  
pp. 1051-1059 ◽  
Author(s):  
William B. Eubank ◽  
Udo P. Schmiedl ◽  
Chun Yuan ◽  
Christopher D. V. Black ◽  
Kenneth E. Kellar ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Wall Thickness ◽  
Signal Intensity ◽  
Lumen Diameter ◽  
Black Blood

Lipoma in olecranon bursa: A case report

2021 ◽  
Vol 3 ◽  
pp. 67-69
Author(s):  
Shalini Agarwal ◽  
Jyoti Siwach ◽  
Ramneet Wadi ◽  
Nipun Gupta
Keyword(s):  
Magnetic Resonance Imaging ◽  
Case Report ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Local Anesthesia ◽  
Signal Intensity ◽  
Ultrasound Examination ◽  
Fat Cells ◽  
Resonance Imaging ◽  
Diffusion Weighted Images

We report a case of a 55-year-old male patient who presented with swelling over his right elbow of 5-year duration. An ultrasound examination revealed an echogenic mass within the olecranon bursa. On magnetic resonance imaging, the mass revealed the signal intensity of fat, and it was attached to the bursal lining by means of a pedicle. There was no restriction on diffusion-weighted images and no significant contrast enhancement. Excision was performed under local anesthesia. The excised specimen revealed mature fat cells on histopathology.

scholarly journals Effect of Stellate Ganglion Block on the Cerebrovascular System

2010 ◽  
Vol 113 (4) ◽  
pp. 936-944 ◽  
Author(s):  
Chang-Ki Kang ◽  
Seung-Taek Oh ◽  
Rack Kyung Chung ◽  
Hyon Lee ◽  
Chan-A Park ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Carotid Artery ◽  
Signal Intensity ◽  
Ophthalmic Artery ◽  
Stellate Ganglion ◽  
Stellate Ganglion Block ◽  
External Carotid Artery ◽  
External Carotid ◽  
Ganglion Block

Background Several studies have shown that stellate ganglion block (SGB) is an effective treatment for certain cerebrovascular related diseases; however, the direct effect of SGB on the cerebral vasculature is still unknown. The present study investigated the effect of SGB on the cerebral vascular system using magnetic resonance angiography. Methods Time-of-flight magnetic resonance angiography images of 19 healthy female volunteers (mean ages of 46.4 ± 8.9 yr) were obtained before and after SGB with 1.5-T magnetic resonance imaging. The authors determined successful interruption of sympathetic innervation to the head with the appearance of Horner syndrome and conjunctival injection. We measured changes in the average signal intensity and diameter of the major intracranial and extracranial arteries and their branches, which were presented with mean (±SE). Results The signal intensity changes were observed mainly in the ipsilateral extracranial vessels; the external carotid artery (11.2%, P &lt; 0.001) and its downstream branches, such as the occipital artery (9.5%, P &lt; 0.001) and superficial temporal artery (14.1%, P &lt; 0.001). In contrast, the intensities of the intracranial arteries did not change with the exception of the ipsilateral ophthalmic artery, which increased significantly (10.0%, P = 0.008). After SGB, only the diameter of the ipsilateral external carotid artery was significantly increased (26.5%, P &lt; 0.001). Conclusions We were able to observe significant changes in the extracranial vessels, whereas the intracranial vessels were relatively unaffected (except for the ophthalmic artery), demonstrating that both perivascular nerve control and sympathetic nerve control mechanisms may contribute to the control of intracranial and extracranial blood vessels, respectively, after SGB.

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