Main Cerebral Arteries Research Articles

Clinical and neuroradiological aspects of Sneddon's syndrome and primary antiphospholipid antibody syndrome. A follow-up study.

We performed a study to investigate differences and similarities between patients with Sneddon's syndrome and those with primary antiphospholipid syndrome (PAS), by clinical follow-up, magnetic resonance imaging (MRI) and angiography. Nine patients with Sneddon's syndrome and 11 patients with PAS were assessed at diagnosis and followed for a mean of 6 years. The clinical and MRI findings indicated that Sneddon's syndrome and PAS are distinct entities. Patients with Sneddon's syndrome had a progressive clinical course with increasing disability and cognitive deterioration; patients with PAS had a more benign course. Infarcts in territories of the main cerebral arteries were frequent in PAS, while leukoaraiosis and small lacunar infarcts were more common in Sneddon's syndrome. In 3 of 7 women initially diagnosed with PAS, the diagnosis was changed to systemic lupus erythematosus during follow-up. Differential diagnosis of Sneddon's syndrome and PAS is important, as early therapy is effective for the latter, more benign, condition.

Role of Ca(2+) channels in NE-induced increase in [Ca(2+)](i) and tension in fetal and adult cerebral arteries.

In vascular smooth muscle, elevation of agonist-induced intracellular Ca(2+) concentration ([Ca(2+)](i)) occurs via both Ca(2+) release from intracellular stores and Ca(2+) influx across the plasma membrane. In the cerebral vasculature of the fetus and adult the relative roles of these mechanisms have not been defined. To test the hypothesis that plasma membrane L-type and receptor-operated Ca(2+) channels play a key role in NE-induced vasoconstriction via alterations in plasma membrane Ca(2+) flux and that this may change with developmental age, we performed the following study. In main branch middle cerebral arteries (MCA) from near-term fetal ( approximately 140 days) and nonpregnant adult sheep, we quantified NE-induced responses of vascular tension and [Ca(2+)](i) (by use of fura 2) under standard conditions in response to several Ca(2+) channel blockers and in response to zero extracellular Ca(2+). In fetal and adult MCA, maximal NE-induced tensions (g) were 0.91 +/- 0.12 (n = 10) and 1.61 +/- 0.13 (n = 12), respectively. The pD(2) values for NE-induced tension were both 6.0 +/- 0.1, whereas the fetal and adult maximum responses (%K(max)) were 107 +/- 16 and 119 +/- 7, respectively. The fetal and adult pD(2) values for NE-induced increase of [Ca(2+)](i) were 6.2 +/- 0.1 and 6.4 +/- 0.1, respectively, whereas maximum [Ca(2+)](i) responses were 81 +/- 9 and 103 +/- 15% of K(max), respectively. After 10(-5) M NE-induced contraction, nifedipine resulted in dose-dependent decrease in vessel tone and [Ca(2+)](i) with pIC(50) values for fetal and adult tensions of 7.3 +/- 0.1 and 6.6 +/- 0.1, respectively (P < 0.01; n = 4 each), whereas pIC(50) for [Ca(2+)](i) responses were 7.2 +/- 0.1 and 6.9 +/- 0.1, respectively. The pIC(50) values for tension for diltiazem and verapamil were somewhat lower but showed a similar relationship. The receptor-operated Ca(2+) channel blocker 2-nitro-4 carboxyphenyl-N,N-diphenyl carbamate showed little effect on NE-induced vessel contractility or [Ca(2+)](i). In the absence of extracellular Ca(2+) for 2 min, 10(-5) M NE resulted in markedly attenuated responses of adult MCA tension and [Ca(2+)](i) to 39 +/- 7 and 73 +/- 8% of control values (n = 4). For fetal MCA, exposure to extracellular Ca(2+) concentration resulted in essentially no contractile or [Ca(2+)](i) response (n = 4). Similar blunting of NE-induced tension and [Ca(2+)](i) was seen in response to 10(-3) M lanthanum ion. These findings provide evidence to suggest that especially in fetal, but also in adult, ovine MCA, Ca(2+) flux via L-type calcium channels plays a key role in NE-induced contraction. In contrast, Ca(2+) flux via receptor-operated Ca(2+) channels is of less importance. This developmental difference in the role of cerebrovascular plasma membrane Ca(2+) channels may be an important association with increased Ca(2+) sensitivity of the fetal vessels.

3D Gadolinium-Enhanced and 3D TOF MRA of the Brain

We prospectively compared 3D Gadolinium-enhanced and 3D-TOF MR angiographic acquisition techniques on the main cerebral arteries and cortical branches.

STA-proximal MCA bypassの効果

We investigated cerebral blood flow (CBF) and metabolism in patients with hemodynamic ischemia by positron emission tomography (PET) and thermal diffusion flow meter. We also studied neuropsychological functions to evaluate the effects of surgical revascuralization.Bypass surgery of the superficial temporal artery to the proximal middle cerebral artery was performed on 26 patients satisfying the following categories: 1) stenosis or occlusive lesion in main cerebral arteries; 2) no marked focus of infarction on CT or MRI. PET was performed before and 1 month after the operation, and CBF, the cerebral metabolic rate of oxygen (CMRO2) and oxygen extraction fraction (OEF) were analyzed. Cerebrovascular reserve capacity (CVRC) was also calculated after acetazolamide challenge. CBF during the operation was continuously measured with a thermal diffusion flow meter. CO2 response of CBF was analyzed before and after anastomosis. Neuropsychological functions were evaluated by Hasegawa dementia scale revised (HDS-R), minimental state examination (MMSE) and Wechsler adult intelligence scale revised (WAIS-R).Before the operation, increase in OEF accorded with the decrease in CBF, and a significant relationship between both CBF and CVRC, and OEF and CVRC was found. A decrease in CVRC was noted prior to a decrease in CBF and elevation of OEF. CVRC caused by acetazolamide might reflect CO2 reactivity. Significant improvement of CBF and CVRC, and normalization of OEF were observed after the operation. Also, significant improvement of neuropsychological function was observed by HDS-R and WAIS-R. Disturbance in neuropsychological function might reflect elevation of OEF.

Proximal aneurysms in association with arteriovenous malformations: do they resolve following obliteration of the malformation with stereotactic radiosurgery?

One-hundred consecutive patients were identified who had arteriovenous malformations (AVMs) treated by stereotactic radiosurgery (STRS) which were totally obliterated as shown by follow-up angiography. Of these cases, seven had intracerebral aneurysms at initial angiography, two of which were multiple. Five patients had saccular aneurysms at commonly recognized sites on the circle of Willis or main proximal cerebral arteries, while two patients had aneurysms on distal AVM feeder arteries in atypical sites (one saccular, one fusiform). Saccular aneurysms at typical sites were found to be unchanged in size following AVM obliteration. The significance of this finding in the management of patients who present with subarachnoid haemorrhage and who have both aneurysms and AVMs is discussed.

P-3-288 - Influence of ethanol on blood flow velocity in main cerebral arteries: Experimental transcranial doppler study in humans

P-3-288 - Influence of ethanol on blood flow velocity in main cerebral arteries: Experimental transcranial doppler study in humans

An in vitro anatomic model of the human cerebral arteries with saccular arterial aneurysms

An in vitro model of the main human cerebral arteries with or without saccular arterial aneurysms is presented. A cast of the cerebral arteries was obtained in a human specimen. Three aneurysms were simulated and added to the cast. Wax copies of the cast were produced, and embedded with liquid resin solidifying into solid blocks. After evacuation of the wax, a model consisting of a hollow reproduction of the cast within the resin block was obtained. The model is reproducible and anatomically accurate. Since it is transparent to visible light, and compatible with x-ray, magnetic resonance and transcranial doppler techniques, it should prove useful for a wide range of haemodynamic and radiologic investigations. The reported technique may be adapted to any structure with a hollow configuration, allowing for the preparation of arterial and venous models from other vascular areas, as well as models from other anatomic systems, such as the biliary or urinary tracts.

High altitude-induced changes in alpha1-adrenergic receptors and Ins(1,4,5)P3 responses in cerebral arteries.

In response to high-altitude long-term hypoxemia, the cerebral arteries of fetal and adult sheep show decreased contractile responses to norepinephrine (NE) and other agonists. To test the hypothesis that hypoxia-induced developmental and vessel specific cerebral artery contractility changes are mediated, in part, by changes in alpha1-adrenergic receptor (alpha1-AR) density and/or NE-induced inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] responses, we performed the following study. In common carotid (Com) and main branch cerebral (MBC) arteries from normoxic adult ewes and near-term fetuses and those acclimatized to high altitude (3,820 m), we quantified alpha1-AR density (maximal binding in fmol/mg protein) and affinity (dissociation constant in nM) with the alpha1-AR antagonist [3H]prazosin. In addition, we quantified NE-induced Ins(1,4,5)P3 responses in these arteries. With long-term hypoxemia, alpha1-AR density in fetal and adult Com decreased 75% (from 113 +/- 18 to 28 +/- 5 fmol/mg protein) and 66% (from 54 +/- 3 to 18 +/- 4 fmol/mg protein), respectively, from normoxic control values. alpha1-AR density of the fetal and adult MBC decreased 76% (from 47 +/- 4 to 11 +/- 1 fmol/mg protein) and 61% (from 23 +/- 3 to 9 +/- 3 fmol/mg protein), respectively, from controls. In hypoxemic adult Com, the NE-induced Ins(1,4,5)P3 response decreased 51% (from 309 +/- 38 to 151 +/- 24%) from the control value. In fetal and adult MBC, long-term hypoxemia was associated with decreases of 35% (from 345 +/- 40 to 225 +/- 30%) and 44% (from 355 +/- 55 to 199 +/- 16%), respectively, from control values. We conclude that in the adult Com and MBC vessels, acclimatization to high-altitude, long-term hypoxemia was associated with significant decreases in both alpha1-AR density values and Ins(1,4,5)P3 responses to NE. Similarly, in the fetal MBC arteries, high-altitude hypoxemia was associated with marked attenuation of both alpha1-AR density and NE-induced Ins(1,4,5)P3 responses. The magnitude of decreases in NE-induced Ins(1,4,5)P3 responses in these vessels correlated fairly well with the decreases in alpha1-AR density. These findings suggest that changes in noradrenergic receptor-second messenger coupling may play a role in altered cerebrovascular tone in association with high-altitude acclimatization and other forms of long-term hypoxia in both fetus and adult.

Moyamoya disease in Yugoslavia: angiographic study.

The angiographic findings in 31 Yugoslav moyamoya patients, 16 males and 15 females, including four children, were studied by conventional or digital subtraction angiography. The angiographic findings were reviewed for stenoocclusive lesions, form of the main cerebral arteries, transdural anastomoses, and basal vascular networks. There were 27 patients with bilaterally symmetrical or asymmetrical lesions and four with unilateral lesions. In two of these latter four patients, follow-up studies showed progression of the disease to the opposite side. Of 58 sides investigated, stenoocclusive lesions were localized above the origin of the anterior choroidal artery in 33 internal carotid arteries. Occlusions of the anterior and middle cerebral arteries were noted more frequently than stenoses: 89 vs. 27. The majority of the nests of abnormally dilated vessels (73 of 102) were localized in the ethmoidal region and basal ganglia. Analysis of distribution of the transdural collateral pathways to the brain discovered predominant participation of the middle meningeal and occipital arteries (43 of 55). Moyamoya disease in Yugoslavia predominantly affects the adult population, males and females equally, with the slowly progressive course typical for adults, and is mainly confined to the carotid fork and rarely extends to the posterior circulation.

Developmental changes in alpha 1-adrenergic receptors, IP3 responses, and NE-induced contraction in cerebral arteries.

Cerebral arteries show significant developmental and artery-specific changes in noradrenergic-mediated contraction. To test the hypothesis that these changes result from differences in the density of alpha 1-adrenergic receptors (alpha 1-ARs) and/or norepinephrine (NE)-induced inositol 1,4,5-trisphosphate [Ins(1,4,5)P3,IP3] synthesis, we quantified these variables and the NE-induced contraction in the common carotid artery (Com) and main branch cerebral arteries (MBC) from term fetal (approximately 140 gestational day) and newborn (2- to 5-day) sheep and compared them with adult values. In fetal and newborn Com, maximal contractions to NE (percent K+ maximum response) were 132 +/- 14 and 118 +/- 9%, respectively (adult = 92 +/- 7%). For fetal and newborn middle cerebral artery, these values were 34 +/- 10 and 43 +/- 7%, respectively (adult = 24 +/- 7%). alpha 1-AR density values in Com of fetal and newborn sheep were 113 +/- 18 and 106 +/- 4 fmol/mg protein, respectively (adult = 54 +/- 3 fmol/mg protein). For the MBC, density values were 47 +/- 2 and 24 +/- 3 fmol/mg protein, respectively (adult = 23 +/- 3 fmol/protein). In term fetal and newborn MBC, NE produced dose-dependent increases in Ins(1,4,5)P3, the maximal increases above basal values being 245 +/- 40 and 189 +/- 16%, respectively (adult = 254 +/- 35%). Neither fetus nor newborn Com showed significant Ins(1,4,5)P3 responses to NE. We concluded that in fetal and newborn Com and MBC, alpha 1-AR density and NE-induced Ins(1,4,5)P3 response varied as a function of developmental age and specific vessel. However, these variations did not correlate with NE-induced maximum contraction. Thus we reject the hypothesis that age-dependent and vessel-specific differences of cerebral artery adrenergic-mediated contraction are a function of alpha 1-AR density or Ins(1,4,5)P3 response. Rather, the differences would appear to result from other factors such as non-Ins(1,4,5)P3-mediated calcium activation and/or sensitivity to Ins(1,4,5)P3. The studies also suggest considerable potential for maturational modulation of pharmacomechanical coupling and homeostatic regulation of cerebrovascular tone.

Perivascular coating with fibrin glue of cerebral arteries in patients with aneurysmal subarachnoid hemorrhage; incidence of chronic hydrocephalus.

The incidence of chronic hydrocephalus was studied in 39 patients with subarachnoid hemorrhage, who underwent perivascular coating with fibrin glue of cerebral arteries after clipping of aneurysm. A use was made of this procedure in order to prevent vasospasm by keeping the main cerebral arteries away from direct contact with subarachnoid clots. Most cases in this series belonged to group 3 of Fisher's CT grade (33/39, 84.6%). As a result, despite the high CT grade, the incidence of chronic hydrocephalus was as low as 17.9% (7/39), almost in agreement with those of the previous literature. In conclusion, (1) coating with fibrin glue did not increase the incidence of chronic hydrocephalus and (2) intrathecal application of fibrin glue is a promising method in the field of clinical neurosurgery.

Cerebral circulation assessed by transcephalic electrical impedance during the first day of life--a potential predictor of outcome?

Pulsatile changes in intracranial blood volume (transcephalic electrical impedance, delta Z), arterial blood pressure (aBP) and respiration were studied during the first day after birth in 42 neonates with a birth weight of 1040-3850 g and gestational age of 26-36 weeks. The neurological outcome was assessed at 1 year of age to study the predictive ability of delta Z. delta Z, ECG, respirogram and direct aBP were recorded at 8-h intervals. Outcome was adverse in seven infants of whom two died from severe peri-intraventricular haemorrhage. PCO2 was higher (6.2 kPa) in the infants with adverse outcome than in those infants with favourable outcome (5.0 kPa) (P = 0.004). Blood glucose (4.5 vs. 3.3 mmol/l, P = 0.030) and first day administration of fluid (80 vs. 63 ml/kg/day, P = 0.003) behaved, respectively. Of the infants receiving dopamine therapy, 60% had adverse outcome while only 11% of those not receiving dopamine had adverse outcome (P = 0.016). Of the infants with high diastolic blood pressure levels, 32% had adverse outcome, while none with low diastolic blood pressure levels had adverse outcome (P = 0.031). Spectral analysis was used to examine signal variabilities in the frequency domain. During the first 24 h of life, the variabilities of aBP and respiration were equal in all the infants. The high-frequency delta Z signal variability (1.50-4.00 Hz, heart rate level) was found to be lower in the infants with adverse outcome (330 units) than in the infants with favourable outcome (1280 units, P = 0.017). The low delta Z variability allowed us to assume that there is a decrease of pulsatile cerebral blood flow (CBF) in the infants with adverse outcome. We speculate that this may result from the 'no reflow phenomenon', increased tissue pressure due to ischaemia and/or PIVH, the 'brain sparing effect' or constriction of main cerebral arteries due to increased pressure support or metabolic factors (PCO2, glucose). We believe that transcephalic impedance provides a potential cot-side method for monitoring cerebral circulation in the neonatal period with an ability to predict outcome.

Moyamoya disease in childhood: a familial case report

Moyamoya is an obstructive cerebrovascular disease characterized by a cerebral angiographic picture of stenosis or occlusion of main cerebral arteries with an abnormal vascular network at the base of the brain. No definitive cause has been found for this disease and opinion is still divided between a congenital and an acquired etiology. Hemiplegia of sudden onset and epileptic seizures are the prevailing presentation in childhood, while subarachnoid bleeding occurs more frequently in adults. We report a new case of childhood moyamoya with clinical onset of the neurological symptoms within the 3rd year of life; during the child's illness the maternal grandmother presented with moyamoya disease too. Antiaggregating and calcium-antagonist drugs seem effective in preventing further vascular accidents, while a surgical approach is not possible. Computed tomography, single positron emission computed tomography, and magnetic resonance imaging are very useful in the diagnosis of this rare disease.

Plasticity of the sympathetic nervous system innervating the cerebral arteries in rats

In order to investigate the neuroplasticity of the peripheral sympathetic nervous system innervating the cerebral blood vessels, we observed and traced the sprouting nerve fibers originating in the contralateral superior cervical ganglion (SCG) into the previously denervated cerebral arteries following unilateral excision of the SCG and/or decentralization of the contralateral SCG in young rats (4 weeks old). These nerve fibers were labeled anterogradely with wheat germ aggulutinin-horseradish peroxidase or stained immunohistochemically with anti-tyrosine hydroxylase antibody. Eight weeks after the right SCG excision, reinnervating nerve fibers originating in the contralateral ganglion formed a circular pattern of nerve plexus only on the wall of the main cerebral arteries of the circle of Willis in the ganglionectomized side. However, the decentralization of the contralateral SCG, which was performed simultaneously with a unilateral SCG excision, prevented the nerve sprouting into the denervated regions. Unilateral decentralization of SCG itself failed to affect their distribution pattern or their density of nerve fibers originating in the ganglion. It is concluded that in the young rat the outgrowth of the sympathetic nerve fibers into the denervated cerebral arteries was strongly impeded by the disconnection of ganglion cells from the central nervous system, while the decentralization alone could not affect the innervation pattern of the postganglionic fibers which have been already built-up in the cerebral arterial system.

Patterns of reinnervation of denervated cerebral arteries by sympathetic nerve fibers after unilateral ganglionectomy in rats

In order to clarify the manner in which previously denervated cerebral arteries become reinnervated after unilateral excision of the superior cervical ganglion (SCG), we observed directly the reinnervating sympathetic nerve fibers originating in the contralateral SCG by using anterograde labeling with wheat germ aggulutinin-horseradish peroxidase in rats. The nerve fibers sprouted from the nerve fibers in the contralateral anterior cerebral artery and reinnervated the arterial wall of the anterior cerebral artery of the denervated side as early as one week after ganglionectomy. In addition to this sprouting route, three other reinnervating nerve fiber routes were observed in the circle of Willis of the denervated side two weeks after ganglionectomy: the proximal portion of the internal carotid artery, the route passing between bilateral ethmodial arteries, and the posterior communicating artery. Eight weeks after ganglionectomy, these reinnervating nerve fibers formed a fairly dense plexus in a circular pattern in the circle of Willis. However, the reinnervation could not be observed in the arterial branches derived from the circle of Willis (middle cerebral artery and posterior cerebral artery) even 16 weeks after ganglionectomy. The present results clearly demonstrated the time course, distribution pattern and limitation of the reinnervation from the contralateral SCG following unilateral ganglionectomy. The fact that reinnervation could be observed only in the main cerebral arteries of the circle of Willis, in which the nerve plexus appeared to have a circular pattern, suggests a difference between the qualities of sympathetic innervation controlling the cerebral circulation in these arteries and the other arterial branches related to these differences in reinnervation capacity.

The correlation between immunological reaction in the arterial wall and the time course of the development of cerebral vasospasm in a primate model

To investigate the role of immunological reactions in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH), the authors studied the correlation between immune/inflammatory reactions in the arterial wall and the time course of vasospasm in primates. Twenty monkeys were divided into four groups of 5 animals each: 1) a control group of sham-operated animals, 2) animals subjected to angiography 3 days after the induction of SAH (3-day SAH), 3) animals subjected to angiography 7 days after SAH (1-week SAH), and 4) animals subjected to angiography 7 and 14 days after SAH (2-week SAH). To induce SAH, the main cerebral arteries on the right were dissected free of the arachnoid, and an autologous blood clot was placed around the arteries. To evaluate vasospasm, all animals underwent a baseline angiogram before SAH; angiography was repeated at different intervals in each group, as outlined above. Histopathological changes and the deposition of the immunoglobulin IgG in the arterial wall were evaluated immunohistochemically in each group. The cerebral arteries on the side of the clot showed evidence of mild vasospasm (-24.6% reduction) on the angiogram performed on Day 3, severe vasospasm (-51.7%) on Day 7, and mild vasospasm (-12.8%) on Day 14. The infiltration of inflammatory cells was most marked in the spastic arterial wall in the 1-week SAH group. In the 2-week SAH group, severe myonecrosis and intimal disruption were observed, even in the vessels that showed only mild vasospasm, and the inflammatory reactions had almost abated.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of the Main Fetal Cerebrovascular Areas by Ultrasound Color‐Coded Doppler

The color flow mapping method makes it possible to identify small vessels presently not detected on B‐mode imaging. The main cerebral arteries of normal human fetuses, anterior, middle, and posterior arteries, were investigated by color‐coded Doppler in 45 normal pregnancies. The Pourcelot index R was calculated at different stages of the pregnancy. The values of R (anterior cerebral artery), R (middle cerebral artery), and R (posterior cerebral artery) were compared in each fetus. No significant differences were found when comparing all of the R (anterior cerebral artery) and R (middle cerebral artery) or the R (anterior cerebral artery) and R (middle cerebral artery) at the same gestational age. On the contrary, for each fetus, at any gestational age, the R (anterior cerebral artery) and the R (middle cerebral artery) indices were significantly different (P &lt; 0.01); the index in the middle cerebral artery was higher than that of the anterior cerebral artery. The same difference was observed when comparing R (posterior cerebral artery) and R (middle cerebral artery). The index of the middle cerebral artery was significantly higher than that of the posterior cerebral artery (P &lt; 0.001). On the other hand, no significant difference was found between R (anterior cerebral artery) and R (posterior cerebral artery) at any gestational age (P = 0.4).

CT appearance of bilateral, acute thrombosis of the main cerebral arteries

Acute thrombosis within the lumen of the intracranial artery may occasionally be demonstrated on precontrast CT. The hyperdensity follows the course of the occluded segment of the vessel and an area of low attenuation in the territory of the involved artery is usually present, consistent with infarction. Usually, a single vessel is involved; occlusion of multiple branches occurs less commonly. This report demonstrates a case of diffuse bilateral thrombosis of the main arteries of the anterior circle of Willis.

Histochemical evaluation of the glycosaminoglycans in vasoconstricted human cerebral arteries after subarachnoid haemorrhage.

Sixteen patients dying after subarachnoid haemorrhage (SAH) were investigated with regard to the presence of angiographic vasoconstriction and of glycosaminoglycans in samples from the main cerebral arteries. All patients had a statistically significant (p less than 0.001) vasoconstriction at angiography performed before death. At morphological examination, the vessels of all patients showed signs of intimal thickening, necrosis of the media and leucocyte infiltration of the adventita. The presence of glycosaminoglycans was determined semiquantitatively and did not differ from the values obtained from presumably normal controls. It is suggested that the angiographically verified vasoconstriction found after SAH as well as the morphological changes of the cerebral arteries are not related to a concentration increase of glycosaminoglycans.

ヒト脳血管における脂質および水分の加齢変動

The contents of water and lipids were studied in human cerebral arteries in relation to the aging. Main cerebral arteries were separated from main portions of Willis's circles and main branches of 295 subjects at various ages. The results showed that the water contents ranged from 72 to 74%, the greatest being observed during the 5th decade. Total lipid, cholesterol-ester and triglyceride contents increased more in older cerebral arteries than younger ones. Significant differences in the cholesterol ester content with aging was obtained during the 6th and 7th decades (p<0.05).