Veränderungen zerebrovaskulärer Perfusionsindices nach Karotis-Thrombendarterektomie

VASA ◽  
1999 ◽  
Vol 28 (4) ◽  
pp. 279-282 ◽  
Author(s):  
Müller ◽  
Behnke ◽  
Walter

Background: To study the pattern of cerebral blood flow velocity and cerebral resistance changes after carotid endarterectomy. Patients and methods: In 81 patients (mean age ± SD, 64 ± 8 years) with unilateral carotid endarterectomy (CEA) the systolic, diastolic and mean blood velocities, and the pulsatility index (PI) were recorded in both middle cerebral arteries preoperatively and repetitively postoperatively with the use of transcranial Doppler ultrasound (TCD). Results: In the middle cerebral artery ipsilateral to CEA mean blood velocity was increased 6 hours (64 ± 25 cm/sec; p < 0.005) and 7 days (54 ± 15 cm/sec; p < 0.05) after CEA and had returned to the preoperative level (49 ± 11 cm/sec) after 3 months. Compared to preoperatively (0.86 ±. 22), the PI was significantly increased at 6 hours examination (1.03 ±. 23, p < 0.005), and remained increased thereafter. A pathologically increased mean blood velocity (> 83 cm/sec) 6 hours after CEA occurred in 11 patients, two of them developed a slight hyperperfusion syndrome. In the contralateral middle cerebral artery, only the diastolic blood velocity showed significant changes (preoperatively, 35 ± 12 cm/sec; 3 months after CEA, 33 ± 8 cm/sec; p < 0.05). Conclusions: Using TCD, hemodynamic changes occur predominantly in the middle cerebral arteries ipsilateral to CEA. Early postoperative TCD studies may be of help to identify patients at risk to develop a hyperperfusion syndrome.

2007 ◽  
Vol 106 (1) ◽  
pp. 56-64 ◽  
Author(s):  
Timothy J. McCulloch ◽  
Christopher L. Thompson ◽  
Martin J. Turner

Background Intravenous and inhalational anesthetic agents have differing effects on cerebral hemodynamics: Sevoflurane causes some vasodilation, whereas propofol does not. The authors hypothesized that these differences affect internal carotid artery pressure (ICAP) and the apparent zero flow pressure (critical closing pressure) during carotid endarterectomy. Vasodilation is expected to increase blood flow, reduce ICAP, and reduce apparent zero flow pressure. Methods In a randomized crossover study, the gradient between systemic arterial pressure and ICAP during carotid clamping was measured while changing between sevoflurane and propofol in 32 patients. Middle cerebral artery blood velocity, recorded by transcranial Doppler, and ICAP waveforms were analyzed to determine the apparent zero flow pressure. Results ICAP increased when changing from sevoflurane to propofol, causing the mean gradient between arterial pressure and ICAP to decrease by 10 mmHg (95% confidence interval, 6-14 mmHg; P&lt;0.0001). Changing from propofol to sevoflurane had the opposite effect: The pressure gradient increased by 5 mmHg (95% confidence interval, 2-7 mmHg; P=0.002). Ipsilateral middle cerebral artery blood velocity decreased when changing from sevoflurane to propofol. Cerebral steal was detected in one patient after changing from propofol to sevoflurane. The apparent zero flow pressure (mean+/-SD) was 22+/-10 mmHg with sevoflurane and 30+/-14 mmHg with propofol (P&lt;0.01). There was incomplete drug crossover due to the limited duration of carotid clamping. Conclusions Compared with sevoflurane, ipsilateral ICAP and apparent zero flow pressure are both higher with propofol. Vasodilatation associated with sevoflurane can cause cerebral steal.


1996 ◽  
Vol 85 (1) ◽  
pp. 82-90 ◽  
Author(s):  
Robert M. Bryan ◽  
M. Y. Eichler ◽  
M. W. G. Swafford ◽  
T. D. Johnson ◽  
M. S. Suresh ◽  
...  

Background Because alpha 2 adrenoceptor agonists are used as adjuncts to anesthetics, their effects on the cerebrovascular circulation are of prime importance. We studied changes in the diameter of rat middle cerebral arteries after stimulation of alpha 2 adrenoceptors with UK14,304. Methods Rat middle cerebral arteries were isolated, cannulated at each end with a glass micropipette, and pressurized to 85 mmHg. The middle cerebral arteries were immersed in a bath (37 degrees C) containing physiologic saline solution, and luminally perfused with physiologic saline solution (100 microliters/ min). Changes in vessel diameter were measured after magnification with a microscope. Results Resting diameter of the middle cerebral arteries was 239 +/- 13 microns (n = 8) for the first study. A dose-dependent dilation was produced by addition of UK14,304 to the extraluminal bath; a 10-15% increase in diameter occurred at a concentration of 10(-4)M. The dilations produced by UK14,304 were blocked with selective alpha 2-antagonists, idazoxan and rauwolscine, but not by the selective alpha 1-antagonist, prazosin. The dilations could be blocked by removal of the endothelium, or the nitric oxide synthase inhibitor, N-nitro-L-arginine methyl ester (10(-5) M). The inhibitory effects of N-nitro-L-arginine methyl ester were reversed with the addition of 10(-3) M L-arginine, but not 10(-3) M D-arginine. Furthermore the dilation produced by UK14,304 was completely abolished with pertussis toxin (100 ng/ml). Conclusions It was concluded that the stimulation of alpha 2 adrenoceptors with UK14,304 produced a dilation in the rat middle cerebral artery that (1) was dependent on intact endothelium, (2) involved nitric oxide, and (3) acted via a pertussis toxin-sensitive G protein.


Ultrasound ◽  
2017 ◽  
Vol 25 (2) ◽  
pp. 107-114 ◽  
Author(s):  
GP Anzola ◽  
R Brighenti ◽  
M Cobelli ◽  
A Giossi ◽  
S Mazzucco ◽  
...  

Aim Prospective study on 900 consecutive puerperae to assess normal values and range of the blood flow velocity in the middle cerebral artery in both hemispheres. Material and method M1 and M2 segments of both middle cerebral arteries were assessed in all subjects within 96 hours of delivery. Mean flow velocity was recorded after adjusting for insonation angle. Lindegaard index (LI = middle cerebral artery–Internal Carotid Artery mean flow velocity ratio) was calculated whenever the mean flow velocity exceeded 100 cm/second. Asymmetry indexes were calculated inter hemispherically for M1 and M2 segments separately. Results Mean flow velocities were 74 ± 17 and 72 ± 17 in right and 73 ± 17 and 72 ± 17 cm/second in the left M1 and M2, respectively. A total of 136 subjects (12.1%) exceeded the threshold of 100 cm/second, but LI was consistently <3 in all of them. Mean flow velocity was inversely and independently correlated to haemoglobin levels and to parity. Mean asymmetry indexes were 0.25 ± 23 in M1 and 0.45 ± 25 in M2. Conclusion Mean flow velocity in the middle cerebral artery of healthy subjects in early puerperium is higher than in age-matched non-puerperal women and may exceed the threshold of 100 cm/second with no evidence of intracranial spasm, because of blood loss during delivery. Mean flow velocity is independently correlated with parity. Right-to-left mean flow velocity asymmetry may reach 50% as a consequence of a transient imbalance in vascular tone regulation.


2021 ◽  
Vol 42 (4) ◽  
pp. 174-185
Author(s):  
Gyeong-muk Kim ◽  
Woo-Sang Jung ◽  
Seungwon Kwon ◽  
Chul Jin ◽  
Seung-Yeon Cho ◽  
...  

Objectives: The LI11 (Quchi) acupuncture point has always been included in the Seven acupoints for stroke; however, additional LI11 acupuncture research is needed. In this study, the effect of LI11 acupuncture on cerebral blood flow of the anterior cerebral arteries (ACA) and middle cerebral arteries (MCA) was investigated.Method: This study included 10 healthy young male subjects. Cerebral blood flow velocity and cerebrovascular reactivity were measured using transcranial Doppler sonography. Changes in hyperventilation-induced carbon dioxide (CO2) reactivity and modified ACA and MCA blood flow velocity at 40 mmHg (CV40), blood pressure, and heart rate were observed before and after LI11 acupuncture treatment.Results: A statistically significant increase in contralateral anterior cerebral artery CO2 reactivity (p=0.036) and decrease in contralateral middle cerebral artery CV40 (p=0.047) were observed. No significant difference in mean blood pressure was shown. A statistically significant increase in heart rate occurred after LI11 acupuncture; however, it was not clinically significant as there were negligible changes in the heart rhythm.Conclusions: LI11 acupuncture treatment could improve cerebral blood flow velocity. These results might be explained by regulating endothelium-dependent vessel dilation in the anterior cerebral artery region.Trial registration: This trial has been registered with Clinical Research Information Service, a service of the Korea Centers for Disease Control and Prevention: KCT0004494 (retrospectively registered). https://cris.nih.go.kr/cris/search/search_result_st01.jsp?seq=15359


Neurosurgery ◽  
2011 ◽  
Vol 70 (6) ◽  
pp. 1472-1480 ◽  
Author(s):  
Byung-Sun Seo ◽  
Yoon-Soo Lee ◽  
Hyuk-Gee Lee ◽  
Jeong-Ho Lee ◽  
Kee-Young Ryu ◽  
...  

Abstract BACKGROUND: An aplastic or twiglike middle cerebral artery (Ap/T-MCA) is an extremely rare congenital anomaly related to interference in the normal embryonic development of the MCA. OBJECTIVE: To evaluate the clinical and radiological features of patients with an Ap/T-MCA. METHODS: A total of 1749 conventional cerebral angiography procedures were performed in 1282 patients from January 2005 to July 2011 at Daegu Fatima Hospital. The images were evaluated for cerebral arterial anomalies. The radiological features of an Ap/T-MCA, coexisting anomalies, and clinical manifestations were recorded. These prospectively maintained databases were analyzed retrospectively. RESULTS: Ap/T-MCAs were found in 15 patients (1.17% angiographic incidence). The anomalies were confined to unilateral M1 segment, and no stenoses were seen in the adjacent major arteries. Of 15 patients, 6 (40%) had hemorrhagic strokes, 5 (33.3%) had ischemic strokes, and 4 (26.7%) had no symptoms. Aneurysms were found in 5 patients (33.3%). Coexisting cerebral arterial anomalies were seen in 12 patients (80%). Ten patients underwent conservative treatments, and the remaining 5 underwent surgical treatments, such as hematoma aspiration, indirect revascularization, and clipping or coiling of aneurysms. CONCLUSION: An Ap/T-MCA is a rare anomaly and should be differentiated from moyamoya conditions and degenerative steno-occlusive diseases of the middle cerebral artery. Coexisting anomalies of the anterior or middle cerebral arteries are frequent. This anomaly is vulnerable to both hemorrhagic and ischemic strokes.


2004 ◽  
Vol 24 (5) ◽  
pp. 526-530 ◽  
Author(s):  
Iris Seitz ◽  
Ulrich Dirnagl ◽  
Ute Lindauer

Cortical spreading depression (CSD) is accompanied by hyperemia followed by long-lasting hypoperfusion and impaired cerebrovascular reactivity. The authors show that vasodilation to extraluminal acidosis (pH 7.0) and increased concentrations of extraluminal potassium (12, 20, 40 mmol/L) was significantly reduced in isolated rat middle cerebral arteries after CSD in vivo before the artery was isolated, compared with sham-operated controls. Application of 80-mmol/L potassium induced vasoconstriction after CSD. Therefore, the impairment of vascular reactivity after CSD in vivo occurs, at least in part, at the vascular level itself.


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