Abstract 3829: Extraluminal Protruding Plaques in Intracranial Arteries. An angiographic and pathological analysis of Circle of Willis specimens from the Nun Study

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
M Fareed K Suri ◽  
Shahram Majidi ◽  
Joyce Meints ◽  
Afshin A Divani ◽  
Adnan I Qureshi

BACKGROUND There is little data about extraluminal protruding plaques in intracranial arteries. Such plaques may not cause luminal stenosis and may be undetectable by standard angiographic modalities. It is important to identify the prevalence of such plaques because these plaques may be a cause of thrombosis and ischemic events in patients with cryptogenic strokes. OBJECTIVE To identify the prevalence of extraluminal protruding plaques in intracranial arteries from autopsy specimens of Nun Study. METHODS A random sample of 54 specimens was selected from Nun Study repository of post-mortem intracranial arteries (Circle of Willis). The Nun Study is a longitudinal study of aging and Alzheimer's disease funded by the National Institute on Aging including 678 participants who are 75 to 106 years of age. Basilar artery and proximal middle cerebral arteries were inspected and arteries with plaques were identified. The specimens were placed in a liquid container and an angiographic catheter was placed in vessel of interest. Using iodinated contrast media and Ziehm Vista C-arm, angiography was obtained in multiple planes. Percentage luminal stenosis was measured using normal proximal or distal segment of the vessel as reference. Using microscopic images, extraluminal protruding plaques was then sequentially measured. Percentage increase in extraluminal wall diameter was calculated as (extraluminal diameter at plaque site - normal diameter)/normal diameter x100. RESULTS Out of 162 samples, plaques were identified in 126 samples. The characteristics of the plaques are tabulated. The percentage increase in extraluminal wall diameter was 10.33 ± 8.13. For vessel with angiographically occult plaques, the percentage increase in extraluminal wall diameter was 9.2±3.2. In extraluminal protruding plaques, the median protrusion was 0.3 mm and maximum protrusion was 0.9 mm. There was no difference between the percentage extraluminal protrusion between the middle cerebral (0.3±0.1) and basilar artery plaques (0.36±0.2), p=0.8. The frequency of extraluminal plaques without angiographic stenosis of any severity was higher than extraluminal plaques with angiographic stenosis (52% and 56% for middle cerebral artery and basilar artery, respectively). CONCLUSIONS There appears to be a high prevalence of extraluminal protruding plaques among elderly persons and most of these plaques are not detected by angiography. Newer, imaging modalities like vessel wall high resolution visusalization by magnetic resonance imaging may help identify the prevalencc and ischemic event risk associated with such plaques.

Neurology ◽  
2012 ◽  
Vol 78 (Meeting Abstracts 1) ◽  
pp. PD2.007-PD2.007
Author(s):  
M. Suri ◽  
S. Majidi ◽  
K. Santa Cruz ◽  
J. Meints ◽  
A. Qureshi

2021 ◽  
Vol 2 (1) ◽  
pp. 37-41
Author(s):  
Prakash Sharma ◽  
Subita Lalchan ◽  
Subhash KC ◽  
Merina Gyawali ◽  
Niraj Kushwaha

Introduction: The circle of Willis (CoW), which is located at the base of the brain is the most important anastomosis between the internal carotid and vertebral system. It is the main distributor of blood to the brain. Methods: CT head and CT angiography were performed using standard scan parameters. Only the tests with normal radiological reports and appropriate technical standards were included in the study. Component of circle of Willis: Anterior cerebral artery (ACA), Middle cerebral artery (MCA), Anterior communicating artery (Acom), Posterior Communicating artery (PCom), Basilar artery (BA) and Posterior cerebral artery (PCA) were identified and their internal diameter were measured. Results: Basilar artery was the artery with largest internal diameter with mean diameter of 2.5 ±0.52 mm. Men had significantly larger arterial sizes than women in all of the intracranial arteries examined except right PCom, Left PCom and right MCA. Right ACA had significantly larger internal diameter in <40 years’ age group. BA, left PCA, Bilateral PCom and MCA showed larger diameter in age group ≥40 years. Conclusion: Men had significantly larger arterial sizes than women in all of the intracranial arteries examined except right PCom, Left PCom and right MCA.


2009 ◽  
Vol 15 (1) ◽  
pp. 81-86 ◽  
Author(s):  
A.S. Puri ◽  
E. Erdem

We describe a case of unusual Enterprise stent navigation through the Circle of Willis in a patient with a basilar tip aneurysm, left internal carotid artery (ICA) occlusion and previous right ICA stenting. Basilar tip aneurysms are known for their therapeutic challenges, especially when the posterior cerebral arteries (PCAs) are incorporated in the aneurysm neck. This becomes more technically demanding if the vertebral artery does not offer a route for stent navigation. We undertook stent-assisted coiling using the horizontal stenting of posterior cerebral arteries via both the posterior and anterior communicating artery navigation. This was necessary because the vertebral arteries were very tortuous, hence not suitable for stent navigation due to their small size and stenosis at their origin. Another compounding factor was the anatomy of the aneurysm neck in relation to the T-shaped origin of both P1 PCAs from the basilar artery. The right ICA was stented previously and the whole navigation was done through this stented artery as the opposite left ICA was occluded at the bifurcation. In addition, there was no visualized posterior communicating artery (PCOM) on the right side, so following navigation through the anterior communicating artery (ACOM) the left PCOM artery was catheterized to reach the PCAs. After horizontal placement of stent, coiling was performed for the residual aneurysm. The outcome of this intervention revealed successful placement of the Enterprise stent in bilateral posterior cerebral arteries covering the aneurysm. Further coiling of the basilar artery aneurysm was done with a good result. No complication was seen in the angiography suite or later in the course of action. Horizontal stent placement in wide-necked basilar aneurysms can be performed via the PCOM and ACOM arteries.


2018 ◽  
Vol 46 (1) ◽  
Author(s):  
Herson Da Silva Costa ◽  
Hélio Norberto De Araújo Júnior ◽  
Ferdinando Vinícius Fernandes Bezerra ◽  
Carlos Eduardo Vale Rebouças ◽  
Danilo José Ayres De Menezes ◽  
...  

 Background: The Rhea americana americana is a wild bird belonging to the group of Ratites, and is important from the scientific point of view given their adaptability to captivity. Considering that information about its morphology is important for the viability of domesticating the species, the aim of this study was to macroscopically identify the brain regions, as well as the cerebral arteries and the cerebral arterial circuit in order to establish the cerebral vascular pattern and systematization.Materials, Methods & Results: Twenty one brains from young and adult Greater Rheas of both sexes were used from animals that had died due to natural causes and were then kept in a freezer. The specimens were thawed and incised in the cervical region to allow exposure of the left common carotid artery, which was cannulated. The vascular system was rinsed with 0.9% saline solution, then perfused with latex Neoprene 650 stained with red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 72 h, and then they were dissected by removing the bones from the skull cap. The brains were analyzed, and the structures were identified, photographed, schematized and denominated. Morphometric measurements were performed on the basilar and cerebellar ventral caudal arteries, recording the values of length and width in millimeters with the aid of a digital caliper. The brain was divided into: telencephalon, diencephalon, brainstem and cerebellum; while externally, the observed structures are: olfactory bulbs, optical lobes, optic nerves, optic chiasm, pituitary and pineal glands. Vascularization was performed by the following arteries: ventral spinal artery, basilar artery, ventricular cerebellar arteries, medium ventricular cerebellar arteries, caudal branches of the carotid arteries of the brain, ventral mesencephalic artery, cerebral caudal arteries, rostral branches of the carotid arteries of the brain, middle cerebral arteries, cerebroethmoidal arteries, rostral intercerebral anastomosis, rostral cerebral arteries, ethmoidal arteries, internal ophthalmic arteries, inter-hemispheric artery, pituitary arteries, dorsal mesencephalic tectal arteries, dorsal cerebellar arteries, occipital, pineal and dorsal hemispherical branches. The cerebral arterial circuit was both caudally and rostrally closed in 100.0% of the samples, being composed of the arteries: basilar artery, caudal branches of the carotid brain, rostral branches of the brain carotid, cerebroethmoidal arteries and rostral intercerebral anastomosis.Discussion: Encephalon classification regarding the presence or absence of gyri is a characteristic associated to evolution­ary aspects among vertebrates, being respectively considered as lisencephalon or girencecephalus when it presents or does not present convolutions. In Greater Rheas, the telencephalon was quite developed, with a relatively rounded shape and the absence of sulci and convolutions in the cortex, which allowed it to be classified as a lisencephalon. Such findings resemble those described for the ostrich and in a comparative study involving kiwis, emus, owls and pigeons, although different sizes and forms of telencephalon development were observed in the latter. Regarding the cerebral arterial circuit, this structure in Rheas was complete and both caudally and rostrally closed in 100.0% of the specimens. Our findings differ from those ob­served for ostriches, in which a rostrally open behavior has been described, while it is caudally closed in 20.0% of cases and opened in 80.0%. Regarding the vascular type of the brain, in the Rhea it was observed that there was only contribution of the carotid system, similar to that found for birds such as ostriches and turkeys which confer a type I encephalic vascularization.Keywords: arteries, brain, arterial circuit, morphometry, ratites.


1991 ◽  
Vol 11 (3) ◽  
pp. 371-379 ◽  
Author(s):  
Chiharu Tanoi ◽  
Yoshio Suzuki ◽  
Masato Shibuya ◽  
Kenichiro Sugita ◽  
Kaoru Masuzawa ◽  
...  

Vasoconstrictor effects of endothelin-1 (ET) were investigated in endothelium-denuded strips of cerebral (basilar and posterior cerebral) and mesenteric arteries of the dog. ET produced a concentration-dependent contraction in these arteries. Contractile responses to lower concentrations (below 3 × 10−10 M) of ET were significantly greater in the cerebral arteries than in the mesenteric artery. Inhibition by nifedipine of the contractile responses to ET was greater in the basilar artery than in the mesenteric artery. After the inhibition by 10−7 M nifedipine, the remaining responses to ET were similar in the two arteries. Cerebral arteries, but not the mesenteric artery, relaxed significantly from the resting level when placed in a Ca2+ -free solution containing 0.1 m M EGTA (0-Ca solution). Readdition of Ca2+ to the cerebral arteries placed in the 0-Ca solution caused a biphasic contraction that was sensitive to nifedipine. When 10−9 M ET was introduced before the Ca2+-induced contraction, this peptide produced only a very small contraction, but enhanced the Ca2+-induced contraction. The extent of the enhancement induced by ET was much greater in the cerebral arteries than in the mesenteric artery. These results indicate that the enhanced responses to ET in the cerebral arteries were dependent to a large extent on Ca2+ influx through voltage-dependent Ca2+ channels (VDCs). It is likely that the VDCs in these arteries are more activated in the resting state than those in the mesenteric artery.


Cephalalgia ◽  
2005 ◽  
Vol 25 (5) ◽  
pp. 344-352 ◽  
Author(s):  
LH Lassen ◽  
B Sperling ◽  
AR Andersen ◽  
J Olesen

The aim of this study was to estimate the effect of Nitric Oxide synthase (NOS)-inhibition (L-NMMA) on the diameter of the middle cerebral artery (MCA) and on regional cerebral blood flow (rCBF). Furthermore, to assess the effect of L-NMMA on acetazolamide induced increases in MCA blood velocity (Vmean) and rCBF. In an open crossover design 12 healthy subjects attended the laboratory twice. The first day 6 mg/kg L-LNMMA i.v. over 15 min preceded 1 g acetazolamide iv over 5 min. Eight days later only acetazolamide was given. Vmean in MCA was determined with transcranial Doppler (TCD) and rCBF with Xe-133 inhalation SPECT at baseline, after L-NMMA and 25 and 55 min after acetazolamide infusion. After L-NMMA the decrease in rCBFMCA was 6.8% (± 7.4) ( P < 0.019, n = 12), whereas Vmean was not affected ( P = 0.83, n = 8). The change in MCA diameter was estimated to -1.3% ( P = 0.44, n = 8). L-NMMA did not affect acetazolamide increases in Vmean ( P = 0.67, n = 8) nor rCBF ( P = 0.29, n = 12). The percentage increase of Vmean was 1.5 times that of rCBF ( n = 8). Our data suggest that the basal tone of human cerebral arterioles but not of conduit arteries is NO-dependent. The action of acetazolamide in man is not NO-dependent.


1974 ◽  
Vol 41 (1) ◽  
pp. 107-112
Author(s):  
Shigeaki Hori ◽  
Williamina A. Himwich

✓ A technique for exposing the vessels in the anterior part of the circle of Willis in the dog is described. Some of the physiological and anatomical characteristics of the anterior communicating and the anterior cerebral arteries are discussed.


2010 ◽  
Vol 299 (2) ◽  
pp. R461-R469 ◽  
Author(s):  
Khodadad Namiranian ◽  
Eric E. Lloyd ◽  
Randy F. Crossland ◽  
Sean P. Marrelli ◽  
George E. Taffet ◽  
...  

We tested the hypothesis that TREK-1, a two-pore domain K channel, is involved with dilations in arteries. Because there are no selective activators or inhibitors of TREK-1, we generated a mouse line deficient in TREK-1. Endothelium-mediated dilations were not different in arteries from wild-type (WT) and TREK-1 knockout (KO) mice. This includes dilations of the middle cerebral artery to ATP, dilations of the basilar artery to ACh, and relaxations of the aorta to carbachol, a cholinergic agonist. The nitric oxide (NO) and endothelium-dependent hyperpolarizing factor components of ATP dilations were identical in the middle cerebral arteries of WT and TREK-1 KO mice. Furthermore, the NO and cyclooxygenase-dependent components were identical in the basilar arteries of the different genotypes. Dilations of the basilar artery to α-linolenic acid, an activator of TREK-1, were not affected by the absence of TREK-1. Whole cell currents recorded using patch-clamp techniques were similar in cerebrovascular smooth muscle cells (CVSMCs) from WT and TREK-1 KO mice. α-linolenic acid or arachidonic acid increased whole cell currents in CVSMCs from both WT and TREK-1 KO mice. The selective blockers of large-conductance Ca-activated K channels, penitrem A and iberiotoxin, blocked the increased currents elicited by either α-linolenic or arachidonic acid. In summary, dilations were similar in arteries from WT and TREK-1 KO mice. There was no sign of TREK-1-like currents in CVSMCs from WT mice, and there were no major differences in currents between the genotypes. We conclude that regulation of arterial diameter is not altered in mice lacking TREK-1.


Sign in / Sign up

Export Citation Format

Share Document