Abstract P509: Signal Intensity in the Middle Cerebral Artery as a Practical and Feasible Index of Hemodynamic Insufficiency Due to Carotid Artery Stenosis

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Takahisa Mori ◽  
Kazuhiro Yoshioka ◽  
Yuichi Miyazaki

Introduction: Intracranial hemorrhage occasionally occurs after carotid revascularization in presents with hemodynamic insufficiency. Positron emission tomography is unavailable in most facilities, and a feasible index is required to identify high-risk patients. Reduced signal intensity (SI) of the middle cerebral artery (MCA) on magnetic resonance angiography (MRA) is associated with postoperative hyperperfusion. Hypothesis: Reduced signal intensity (SI) of the MCA on MRA is associated with decreased regional cerebral blood flow (rCBF) on single-photon emission CT (SPECT) and increased blood-sampling whole-brain oxygen extraction fraction (wb-OEF). Methods: We included patients who: 1) were admitted from 2015 to 2019 for carotid artery stenting (CAS), 2) MRA, and SPECT before CAS, and 3) examined the wb-OEF immediately before CAS. We measured bilateral MCA SI on MRA and defined the MCA relative SI as (SI in the affected MCA)/ (SI in the contralateral MCA). We defined the rCBF% as rCBF in the affected MCA territory against the ipsilateral cerebellum. Before CAS, we sampled blood, measured the arterial oxygen and the venous oxygen content in the dominant-sided jugular vein, and calculated the wb-OEF. We evaluated the correlation between the MCA relative SI, the MCA slow flow, the rCBF%, and the wb-OEF. We estimated the upper limits of the MCA relative SI for the rCBF% < 80% or wb-OEF ≥ 0.40 using the area under the curve (AUC) values derived from the receiver operating characteristic (ROC) curves. Results: During the study period, 150 patients met our inclusion criteria. The MCA relative SI was positively correlated with rCBF% and negatively with the wb-OEF. The ROC curve for the rCBF% < 80% showed that the upper limit of the relative SI was 0.77 (the sensitivity of 53.9%, the specificity of 83.9%, AUC of 0.723). The ROC curve for the wb-OEF ≥ 0.40 showed that the upper limit of the relative SI was 0.95 (the sensitivity of 67.7%, the specificity of 55.2%, AUC of 0.625). Conclusion: Reduced MCA SI on MRA ≤ 0.77 is a practical and feasible index of hemodynamic insufficiency, indicating the decreased rCBF and increased wb-OEF.

2019 ◽  
Vol 80 (06) ◽  
pp. 441-453
Author(s):  
Hiroyuki Katano ◽  
Hiroshi Yamada ◽  
Yusuke Nishikawa ◽  
Kazuo Yamada ◽  
Shigenori Miyachi ◽  
...  

Abstract Objective To investigate the difference in treatment outcomes according to the method used to select the recipient artery in superficial temporal artery–middle cerebral artery (STA-MCA) anastomoses. Methods We retrospectively analyzed the cases of 35 patients who underwent an STA-MCA anastomosis for internal carotid artery/MCA occlusion or stenosis. Patients were divided into two groups based on whether the recipient artery was precisely targeted by single-photon emission computed tomography (SPECT group) or less precisely targeted by visual assessment (Visual group). Then the bypass results in both groups were evaluated postoperatively based on changes in the regional cerebral blood flow (rCBF) and clinical outcomes. Results The delineated recipient artery in magnetic resonance angiography (MRA) matched the intraoperatively selected artery in 87.6% of the SPECT group cases and 83.3% of the Visual group cases. The SPECT group's digital subtraction angiography (DSA) findings coincided with the intraoperative selection in 76.9% of cases, and the MRA findings corresponded with the DSA findings in 92.3%. The postoperative areas with increased rCBF matched the perfused areas of intraoperatively selected arteries in 80.0% of the SPECT group cases and 77.8% of the Visual group cases. Postoperatively increased rCBF areas matching totally or partially with preoperative low-perfusion areas were observed in all cases. Conclusions The present results revealed no significant differences in the change in rCBF in the low-perfusion area between the patients whose recipient arteries were selected by SPECT or visual assessment.


2004 ◽  
Vol 100 (1) ◽  
pp. 128-132 ◽  
Author(s):  
Kazuhide Furuya ◽  
Nobutaka Kawahara ◽  
Akio Morita ◽  
Toshimitsu Momose ◽  
Shigeki Aoki ◽  
...  

✓ Superficial temporal artery—middle cerebral artery (STA—MCA) anastomosis is a standard surgical therapeutic option in patients with moyamoya disease. Most patients experience improvement in their clinical symptoms immediately after surgery. The authors report on the case of a 39-year-old man with moyamoya disease who suffered from temporary and frequent neurological deterioration after undergoing a left STA—MCA anastomosis. Hemodilution and hypervolemia therapies did not improve his course. Technetium-99m hexamethylpropyleneamine oxime single-photon emission tomography scans demonstrated focal intense accumulation of the tracer in the frontal operculum on the side of the surgery. Although diffusion-weighted magnetic resonance (MR) imaging demonstrated no abnormalities except for the postoperative change, perfusion-weighted MR images and MR digital subtraction angiography revealed focal hyperperfusion in the left frontal operculum where the cerebral perfusion reserve was severely disturbed preoperatively. This evidence strongly supports the notion that focal hyperperfusion observed after STA—MCA anastomosis could occur in the poor perfusion reserve area preoperatively and could cause temporary neurological deterioration.


Author(s):  
Takahisa Mori ◽  
Kazuhiro Yoshioka ◽  
Yuhei Tanno ◽  
Shigen Kasakura ◽  
Yuichi Miyazaki

Abstract Objectives Angiographic “slow flow” in the middle cerebral artery (MCA), caused by carotid stenosis, may be associated with high oxygen extraction fraction (OEF). If the MCA slow flow is associated with a reduced relative signal intensity (rSI) of the MCA on MR angiography, the reduced rSI may be associated with a high OEF. We investigated whether the MCA slow flow ipsilateral to carotid stenosis was associated with a high OEF and aimed to create a practical index to estimate the high OEF. Methods We included patients who underwent digital subtraction angiography (DSA) and MRA between 2015 and 2019 to evaluate carotid stenosis. MCA slow flow by image count using DSA, MCA rSI, minimal luminal diameter (MLD) of the carotid artery, carotid artery stenosis rate (CASr), and whole-brain OEF (wb-OEF) was evaluated. When MCA slow flow was associated with a high wb-OEF, the determinants of MCA slow flow were identified, and their association with high wb-OEF was evaluated. Results One hundred and twenty-seven patients met our inclusion criteria. Angiographic MCA slow flow was associated with high wb-OEF. We identified MCA rSI and MLD as determinants of angiographic MCA slow flow. The upper limits of MCA rSI and MLD for angiographic MCA slow flow were 0.89 and 1.06 mm, respectively. The wb-OEF was higher in patients with an MCA rSI ≤ 0.89 and ipsilateral MLD ≤ 1.06 mm than patients without this combination. Conclusions The combination of reduced MCA rSI and ipsilateral narrow MLD is a straightforward index of high wb-OEF. Key Points • The whole-brain OEF in patients with angiographic slow flow in the MCA ipsilateral to high-grade carotid stenosis was higher than in patients without it. • Independent determinants of MCA slow flow were MCA relative signal intensity (rSI) on MRA or minimal luminal diameter (MLD) of the carotid stenosis. • The wb-OEF was higher in patients with an MCA rSI ≤ 0.89 and ipsilateral MLD ≤ 1.06 mm than patients without this combination.


2000 ◽  
Vol 20 (9) ◽  
pp. 1372-1379 ◽  
Author(s):  
Christina Kruuse ◽  
Torsten B. Jacobsen ◽  
Lisbeth H. Lassen ◽  
Lars L. Thomsen ◽  
Steen G. Hasselbalch ◽  
...  

Dipyridamole is used for secondary prophylaxis in ischemic stroke and as a vasodilator agent in myocardial scintigraphy. An important side effect to administering dipyridamole is headache. The aim of the current study was to investigate the effects of dipyridamole on cerebral blood flow, large artery diameter, and headache induction. Twelve healthy subjects were included in this single-blind placebo-controlled study in which placebo (0.9% NaCl) and dipyridamole 0.142 mg/kg·min were administered intravenously over 4 minutes 1 hour apart. Blood flow velocity in the middle cerebral artery (Vmca) was recorded by transcranial Doppler and regional cerebral blood flow in the middle cerebral artery (rCBFmca) was measured using single photon emission computed tomography and 133Xenon-inhalation. Blood pressure, heart rate, and pCO2 were measured repeatedly. Headache response was scored every 10 minutes on a verbal scale from 0 to 10 (10 = worst). Dipyridamole caused a decrease in pCO2 ( P < 0.001). pCO2 corrected rCBFmca was 41.7 ± 6.9 mL/100 g ·min after placebo versus 41.2 ± 6.9 after dipyridamole ( P ≥ 0.05). pCO2 corrected Vmca decreased 8.4% ± 11.7 ( P < 0.001) after dipyridamole, indicating a mean 5.6% ± 6.7 ( P = 0.005) relative increase of the arterial diameter. After dipyridamole the median peak headache score was 2 (range 0 to 7) compared with 0 (range 0 to 3) after placebo ( P = 0.02). Dilatation of the middle cerebral artery outlasted the headache response. In conclusion, dipyridamole causes a modest pCO2 independent dilatation of the MCA, which is time-linked to the onset, but not to the cessation, of headache.


2018 ◽  
Vol 125 (5) ◽  
pp. 1576-1584 ◽  
Author(s):  
Taiki Miyazawa ◽  
Shigeki Shibata ◽  
Kumiko Nagai ◽  
Ai Hirasawa ◽  
Yoshio Kobayashi ◽  
...  

Transcranial Doppler (TCD) ultrasonography is a noninvasive technique allowing continuous recording of cerebral blood flow (CBF) velocity. However, it is unclear whether the CBF estimated by TCD would be reliable for the comparison between individuals. The present study aimed to clarify the relationship between middle cerebral artery blood flow (MCA BF) measured by TCD and regional and total CBF measured by single-photon emission computed tomography (SPECT-CBF) with a quantification software program, a three-dimensional stereotaxic region of interest template. We recruited 91 elderly subjects with and without dementia. MCA blood flow velocity (MCA V) and middle cerebral artery cross-sectional area (AM) were measured by TCD and magnetic resonance angiography, respectively. MCA BF was calculated by the product of MCA V and AM. Diastolic or mean MCA V and MCA BF were significantly correlated with SPECT-CBF in several segments. Interestingly, the correlation coefficient in the temporal segment of SPECT-CBF was higher than those of the other segments. Moreover, correlations between MCA BF and SPECT-CBF were stronger as compared with those between MCA V and SPECT-CBF. These findings suggest that both mean MCA V and MCA BF with TCD ultrasonography would be useful for CBF comparison between individuals especially in the temporal region, although estimated blood flow with arterial area seems to be better than using simple flow velocity. NEW & NOTEWORTHY Correlations between middle cerebral artery blood flow (MCA BF) calculated by the product of MCA blood flow velocity (MCA V) and middle cerebral artery cross-sectional area and regional and total cerebral blood flow (CBF) measured by single-photon emission computed tomography (SPECT-CBF) were stronger as compared with those between MCA V and SPECT-CBF. These findings suggest that both mean MCA V and MCA BF would be useful for CBF comparison between individuals although estimated blood flow with arterial area seems to be better than using simple flow velocity.


2012 ◽  
Vol 18 (2) ◽  
pp. 213-220 ◽  
Author(s):  
A. Abe ◽  
T. Ueda ◽  
M. Ueda ◽  
S. Nogoshi ◽  
Y. Nishiyama ◽  
...  

This study evaluated the recoveries of cerebrovascular reserves (CVR) after applying percutaneous transluminal angioplasty (PTA) to patients with symptomatic middle cerebral artery (MCA) stenosis of varying severity. The patients were submitted to single photon emission computed tomography (SPECT) to obtain their regional cerebral blood flows at resting stage (rCBFrest) and acetazolamide-challenged CBF in five regions of interest (ROIs), including the MCA, on the ipsilateral and contralateral sides of the hemisphere. rCVR values were then calculated from these CBF data to evaluate the CVR recoveries after PTA treatment. When the PTA effects were statistically analyzed of the patients dichotomized into more severe (n=9) and less severe (n=5) groups, distinctly significant ROI-specific PTA effectiveness was observed for CVR rather than CBF values in the patients of the severer group.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tae Jung Kim ◽  
Jae-Myoung Kim ◽  
Soo-Hyun Park ◽  
Jong-Kwan Choi ◽  
Hyeon-Min Bae ◽  
...  

AbstractInadequate cerebral perfusion is a risk factor for cerebral ischemia in patients with large artery steno-occlusion. We investigated whether prefrontal oxyhemoglobin oscillation (ΔHbO2, 0.6–2 Hz) was associated with decreased vascular reserve in patients with steno-occlusion in the large anterior circulation arteries. Thirty-six patients with steno-occlusion in the anterior circulation arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery) were included and compared to thirty-six control subjects. Patients were categorized into two groups (deteriorated vascular reserve vs. preserved vascular reserve) based on the results of Diamox single- photon emission computed tomography imaging. HbO2 data were collected using functional near-infrared spectroscopy. The slope of ΔHbO2 and the ipsilateral/contralateral slope ratio of ΔHbO2 were analyzed. Among the included patients (n = 36), 25 (69.4%) had deteriorated vascular reserve. Patients with deteriorated vascular reserve had a significantly higher average slope of ΔHbO2 on the ipsilateral side (5.01 ± 2.14) and a higher ipsilateral/contralateral ratio (1.44 ± 0.62) compared to those with preserved vascular reserve (3.17 ± 1.36, P = 0.014; 0.93 ± 0.33, P = 0.016, respectively) or the controls (3.82 ± 1.69, P = 0.019; 0.94 ± 0.29, P = 0.001). The ipsilateral/contralateral ΔHbO2 ratio could be used as a surrogate for vascular reserve in patients with severe steno-occlusion in the anterior circulation arteries.


2021 ◽  
Author(s):  
Kristine Ravina ◽  
Joshua Bakhsheshian ◽  
Joseph N Carey ◽  
Jonathan J Russin

Abstract Cerebral revascularization is the treatment of choice for select complex intracranial aneurysms unamenable to traditional approaches.1 Complex middle cerebral artery (MCA) bifurcation aneurysms can include the origins of 1 or both M2 branches and may benefit from a revascularization strategy.2,3 A novel 3-vessel anastomosis technique combining side-to-side and end-to-side anastomoses, allowing for bihemispheric anterior cerebral artery revascularization, was recently reported.4  This 2-dimensional operative video presents the case of a 73-yr-old woman who presented as a Hunt-Hess grade 4 subarachnoid hemorrhage due to the rupture of a large right MCA bifurcation aneurysm. The aneurysm incorporated the origins of the frontal and temporal M2 branches and was deemed unfavorable for endovascular treatment. A strategy using a high-flow bypass from the external carotid artery to the MCA with a saphenous vein (SV) graft was planned to revascularize both M2 branches simultaneously, followed by clip-trapping of the aneurysm. Intraoperatively, the back walls of both M2 segments distal to the aneurysm were connected with a standard running suture, and the SV graft was then attached to the side-to-side construct in an end-to-side fashion. Catheter angiograms on postoperative days 1 and 6 demonstrated sustained patency of the anastomosis and good filling through the bypass. The patient's clinical course was complicated by vasospasm-related right MCA territory strokes, resulting in left-sided weakness, which significantly improved upon 3-mo follow-up with no new ischemia.  The patient consented for inclusion in a prospective Institutional Review Board (IRB)-approved database from which this IRB-approved retrospective report was created.


2006 ◽  
Vol 105 (1) ◽  
pp. 142-147 ◽  
Author(s):  
Ryoma Morigaki ◽  
Masaaki Uno ◽  
Atsuhiko Suzue ◽  
Shinji Nagahiro

✓ In this paper the authors describe two patients with recurrent hemiparesis and limb shaking that gradually progressed to hemichorea. Cerebral angiography confirmed severe unilateral internal carotid artery stenosis (95%) contra-lateral to the hemichorea. The cerebral blood flow, assessed using N-isopropyl-p-(iodine-123) iodoamphetamine single-photon emission computed tomography (SPECT), disclosed markedly decreased vascular reserves in both patients. After carotid endarterectomy was performed, the hemichorea gradually subsided and SPECT confirmed increased cerebral perfusion. The results in these cases indicate that surgical revascularization is effective for hemichorea due to cerebral ischemia with reduced vascular reserve.


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