scholarly journals Characterization of endothelium-dependent and -independent processes in occipital artery of the rat: Relevance to control of blood flow to nodose sensory cells

2021 ◽  
Author(s):  
Tristan H.J. Lewis ◽  
Paulina M. Getsy ◽  
John F. Peroni ◽  
Rita M. Ryan ◽  
Michael W. Jenkins ◽  
...  
Keyword(s):  
Blood Flow ◽  
Soluble Guanylate Cyclase ◽  
External Carotid Artery ◽  
Vagal Afferents ◽  
External Carotid ◽  
Sensory Cells ◽  
Occipital Artery ◽  
No Donor ◽  
Nodose Ganglia ◽  
Endothelial Denudation

Circulating factors access cell bodies of vagal afferents in nodose ganglia (NG) via the occipital artery (OA). Constrictor responses of OA segments closer in origin from the external carotid artery (ECA) differ from segments closer to NG. Our objective was to determine the role of endothelium in this differential vasoreactivity in rat OA segments. Vasoreactivity of OA segments (proximal segments closer to ECA, distal segments closer to NG) were examined in wire myographs. We evaluated (a) vasoconstrictor effects of 5-hydroxytryptamine (5-HT) in intact and endothelium-denuded OA segments in absence/presence of soluble guanylate cyclase (SGC) inhibitor ODQ, (b) vasodilator responses elicited by NO-donor MAHMA NONOate in intact or endothelium-denuded OA segments in absence/presence of ODQ, and (c) vasodilator responses elicited by endothelium-dependent vasodilator, acetylcholine (ACh), in intact OA segments in absence/presence of ODQ. Intact distal OA responded more to 5-HT than intact proximal OA. Endothelium denudation increased 5-HT potency in both OA segments, especially proximal OA. ODQ increased maximal responses of 5HT in both segments, particularly proximal OA. ACh similarly relaxed both OA segments, effects abolished by endothelial denudation and attenuated by ODQ. MAHMA NONOate elicited transient vasodilation in both segments. Effects of ODQ against ACh were segment-dependent whereas those against MAHMA NONOate were not. The endothelium regulates OA responsiveness in a segment-dependently fashion. Endothelial cells at the OA-ECA junction more strongly influence vascular tone than those closer to NG. Differential endothelial regulation of OA tone may play a role in controlling blood flow and access of circulating factors to NG.

Dynamic Computed Tomography Angiography in Suspected Brain Death: A Noninvasive Biomarker

2014 ◽  
Vol 65 (4) ◽  
pp. 352-359 ◽  
Author(s):  
Santanu Chakraborty ◽  
Reem A. Adas
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Brain Death ◽  
Internal Carotid ◽  
External Carotid Artery ◽  
External Carotid ◽  
Ancillary Test ◽  
Organ Harvesting

Purpose Neurologic determination of death or brain death is primarily a clinical diagnosis. This must respect all guarantees required by law and should be determined early to avoid unnecessary treatment and allow organ harvesting for transplantation. Ancillary testing is used in situations in which clinical assessment is impossible or confounded by other factors. Our purpose is to determine the utility of dynamic computed tomographic angiography (dCTA) as an ancillary test for diagnosis of brain death. Materials and Methods We retrospectively reviewed 13 consecutive patients with suspected brain death in the intensive care unit who had dCTA. Contrast appearance timings recorded from the dCTA data were compared to findings from 15 controls selected from patients who presented with symptoms of acute stroke but showed no stroke in follow-up imaging. Results The dCTA allows us to reliably assess cerebral blood flow and to record time of individual cerebral vessels opacification. It also helps us to assess the intracranial flow qualitatively against the flow in extracranial vessels as a reference. We compared the time difference between enhancement of the external and internal carotid arteries and branches. In all patients who were brain dead, internal carotid artery enhancement was delayed, which occurred after external carotid artery branches were opacified. Conclusion In patients with suspected brain death, dCTA reliably demonstrated the lack of cerebral blood flow, with extracranial circulation as an internal reference. Our initial results suggest that inversion of time of contrast appearance between internal carotid artery and external carotid artery branches at the skull base could predict a lack of distal intracranial flow.

scholarly journals Blood Flow Distribution during Heat Stress: Cerebral and Systemic Blood Flow

2013 ◽  
Vol 33 (12) ◽  
pp. 1915-1920 ◽  
Author(s):  
Shigehiko Ogoh ◽  
Kohei Sato ◽  
Kazunobu Okazaki ◽  
Tadayoshi Miyamoto ◽  
Ai Hirasawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Heat Stress ◽  
Carotid Artery ◽  
Flow Distribution ◽  
Systemic Circulation ◽  
External Carotid Artery ◽  
Whole Body ◽  
External Carotid ◽  
Blood Flows ◽  
Induced Changes

The purpose of the present study was to assess the effect of heat stress-induced changes in systemic circulation on intra- and extracranial blood flows and its distribution. Twelve healthy subjects with a mean age of 22±2 (s.d.) years dressed in a tube-lined suit and rested in a supine position. Cardiac output (Q), internal carotid artery (ICA), external carotid artery (ECA), and vertebral artery (VA) blood flows were measured by ultrasonography before and during whole body heating. Esophageal temperature increased from 37.0±0.2°C to 38.4±0.2°C during whole body heating. Despite an increase in Q (59±31%, P<0.001), ICA and VA decreased to 83±15% ( P=0.001) and 87±8% ( P=0.002), respectively, whereas ECA blood flow gradually increased from 188±72 to 422±189 mL/minute (+135%, P<0.001). These findings indicate that heat stress modified the effect of Q on blood flows at each artery; the increased Q due to heat stress was redistributed to extracranial vascular beds.

Selective Occipital Artery Sonography for Dural Arteriovenous Fistulas

2012 ◽  
Vol 25 (2) ◽  
pp. 212-216
Author(s):  
K. Kono ◽  
M. Mori ◽  
Y. Wakugawa ◽  
M. Yasaka ◽  
Y. Okada ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Resistance Index ◽  
Duplex Sonography ◽  
External Carotid Artery ◽  
External Carotid ◽  
Occipital Artery ◽  
Arteriovenous Fistulas ◽  
Carotid Duplex ◽  
Dural Arteriovenous Fistulas ◽  
Artery Detection

Carotid duplex sonography is a useful method for evaluation of dural arteriovenous fistulas. The resistance index of the external carotid artery has been reported to correlate with the efficacy of treatment and recurrence or aggravation of dural arteriovenous fistulas. Herein, we describe a case of dural arteriovenous fistulas mainly supplied by the occipital artery and show that the resistance index of the occipital artery was more sensitive than that of the external carotid artery. To the best of our knowledge, this is the first report to describe the feasibility of occipital artery detection by carotid duplex sonography and clinical application of the resistance index of the occipital artery for dural arteriovenous fistulas.

scholarly journals Retinal Embolization and Cerebellar Asymptomatic Embolization after Carotid Stenting Using Distal Balloon Protection

2003 ◽  
Vol 9 (3) ◽  
pp. 311-314 ◽  
Author(s):  
S. Islam ◽  
H. Manabe ◽  
S. Hasegawa ◽  
A. Takemura ◽  
M. Nagahata ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Ophthalmic Artery ◽  
Carotid Stenting ◽  
External Carotid Artery ◽  
External Carotid ◽  
Occipital Artery ◽  
Cerebral Embolization ◽  
Intracranial Arteries ◽  
Balloon Protection ◽  
Meningeal Artery

We describe a rare case of having both symptomatic ipsilateral retinal embolization and asymptomatic cerebellar embolization occurring after carotid stenting with use of distal protect device. In this case, external carotid angiograms revealed accessory meningeal artery-ophthalmic artery and occipital artery-vertebral artery anastomoses. This case suggested that the protection for external carotid artery should be considered during carotid stenting to avoid retinal embolization and cerebellar or cerebral embolization in cases showing angiographical anastomoses between external carotid artery and ophthalmic artery or intracranial arteries.

scholarly journals Effect of increases in cardiac contractility on cerebral blood flow in humans

2017 ◽  
Vol 313 (6) ◽  
pp. H1155-H1161 ◽  
Author(s):  
Shigehiko Ogoh ◽  
Gilbert Moralez ◽  
Takuro Washio ◽  
Satyam Sarma ◽  
Michinari Hieda ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Internal Carotid ◽  
Cardiac Contractility ◽  
External Carotid Artery ◽  
External Carotid ◽  
High Dose ◽  
Artery Blood Flow

The effect of acute increases in cardiac contractility on cerebral blood flow (CBF) remains unknown. We hypothesized that the external carotid artery (ECA) downstream vasculature modifies the direct influence of acute increases in heart rate and cardiac function on CBF regulation. Twelve healthy subjects received two infusions of dobutamine [first a low dose (5 μg·kg−1·min−1) and then a high dose (15 μg·kg−1·min−1)] for 12 min each. Cardiac output, blood flow through the internal carotid artery (ICA) and ECA, and echocardiographic measurements were performed during dobutamine infusions. Despite increases in cardiac contractility, cardiac output, and arterial pressure with dobutamine, ICA blood flow and conductance slightly decreased from resting baseline during both low- and high-dose infusions. In contrast, ECA blood flow and conductance increased appreciably during both low- and high-dose infusions. Greater ECA vascular conductance and corresponding increases in blood flow may protect overperfusion of intracranial cerebral arteries during enhanced cardiac contractility and associated increases in cardiac output and perfusion pressure. Importantly, these findings suggest that the acute increase of blood perfusion attributable to dobutamine administration does not cause cerebral overperfusion or an associated risk of cerebral vascular damage. NEW & NOTEWORTHY A dobutamine-induced increase in cardiac contractility did not increase internal carotid artery blood flow despite an increase in cardiac output and arterial blood pressure. In contrast, external carotid artery blood flow and conductance increased. This external cerebral blood flow response may assist with protecting from overperfusion of intracranial blood flow.

Hyperthermia modulates regional differences in cerebral blood flow to changes in CO2

2014 ◽  
Vol 117 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Shigehiko Ogoh ◽  
Kohei Sato ◽  
Kazunobu Okazaki ◽  
Tadayoshi Miyamoto ◽  
Ai Hirasawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Heat Stress ◽  
Carotid Artery ◽  
Thermal Conditions ◽  
External Carotid Artery ◽  
Whole Body ◽  
External Carotid ◽  
Left Middle Cerebral Artery ◽  
Blood Flows

The purpose of this study was to assess blood flow responses to changes in carbon dioxide (CO2) in the internal carotid artery (ICA), external carotid artery (ECA), and vertebral artery (VA) during normothermic and hyperthermic conditions. Eleven healthy subjects aged 22 ± 2 (SD) yr were exposed to passive whole body heating followed by spontaneous hypocapnic and hypercapnic challenges in normothermic and hyperthermic conditions. Right ICA, ECA, and VA blood flows, as well as left middle cerebral artery (MCA) mean blood velocity ( Vmean), were measured. Esophageal temperature was elevated by 1.53 ± 0.09°C before hypocapnic and hypercapnic challenges during heat stress. Whole body heating increased ECA blood flow and cardiac output by 130 ± 78 and 47 ± 26%, respectively ( P < 0.001), while blood flow (or velocity) in the ICA, MCA, and VA was reduced by 17 ± 14, 24 ± 18, and 12 ± 7%, respectively ( P < 0.001). Regardless of the thermal conditions, ICA and VA blood flows and MCA Vmean were decreased by hypocapnic challenges and increased by hypercapnic challenges. Similar responses in ECA blood flow were observed in hyperthermia but not in normothermia. Heat stress did not alter CO2 reactivity in the MCA and VA. However, CO2 reactivity in the ICA was decreased (3.04 ± 1.17 vs. 2.23 ± 1.03%/mmHg; P = 0.039) but that in the ECA was enhanced (0.45 ± 0.47 vs. 0.95 ± 0.61%/mmHg; P = 0.032). These results indicate that hyperthermia is capable of altering dynamic cerebral blood flow regulation.

Spontaneous opening of large occipital-vertebral artery anastomosis during embolization

1980 ◽  
Vol 53 (6) ◽  
pp. 849-850 ◽  
Author(s):  
Robert F. Spetzler ◽  
Michael Modic ◽  
Charles Bonstelle
Keyword(s):  
Carotid Artery ◽  
Vertebral Artery ◽  
Therapeutic Embolization ◽  
External Carotid Artery ◽  
External Carotid ◽  
Occipital Artery ◽  
Dural Arteriovenous Malformation ◽  
Artery Embolization ◽  
Content Type ◽  
Fluoroscopic Control

✓ A patient undergoing external carotid artery therapeutic embolization for obliteration of a dural arteriovenous malformation suddenly developed a large occipital artery to vertebral artery shunt. A devastating stroke was averted because the appearance of the shunt was observed by fluoroscopy, the embolization was stopped, and the shunt verified on a subsequent angiogram. The risk of external carotid artery embolization without constant fluoroscopic control is emphasized.

Direct carotid sinus approach to treatment of bilateral carotid-cavernous fistulas

1988 ◽  
Vol 69 (6) ◽  
pp. 942-944 ◽  
Author(s):  
Pedro Albert ◽  
Manuel Polaina ◽  
Francisco Trujillo ◽  
José Romero
Keyword(s):  
Carotid Artery ◽  
External Carotid Artery ◽  
External Carotid ◽  
Occipital Artery ◽  
Lateral Sinus ◽  
Direct Puncture ◽  
Content Type ◽  
Bilateral Carotid ◽  
The Right ◽  
Carotid Cavernous Fistulas

✓ The authors present a patient with a complex vascular malformation composed of bilateral spontaneous carotid-cavernous fistulas (CCF's). The abnormality was supplied on the right side by the right external carotid artery (ECA) and the right internal carotid artery (ICA), and on the left side only by the left ICA. There was also an arteriovenous communication between the right ECA and the lateral sinus. Surgical embolization of both cavernous sinuses with oxidized cellulose was achieved on one side by direct puncture and on the other through one of its venous affluents, successfully occluding both CCF's and preserving the patency of both ICA's without any neurological deficit. The arteriovenous communication between the right ECA and the lateral sinus was occluded by embolization of the occipital artery and ligation of the right ECA.

Vertebral Artery Disease

Neurosurgery ◽  
1981 ◽  
Vol 9 (5) ◽  
pp. 524-530 ◽  
Author(s):  
Michael B. Pritz ◽  
William F. Chandler ◽  
Glenn W. Kindt
Keyword(s):  
Carotid Artery ◽  
Vertebral Artery ◽  
Medical Management ◽  
Posterior Inferior Cerebellar Artery ◽  
External Carotid Artery ◽  
The Other ◽  
External Carotid ◽  
Occipital Artery ◽  
Cerebellar Artery ◽  
Artery Disease

Abstract The neuroradiological evaluation, perioperative medical management, and microsurgical treatment of variously located vertebral artery lesions are presented. Four types of surgical procedures were undertaken: proximal vertebral artery to common carotid artery end-to-side anastomosis; external carotid artery to midcervical vertebral artery end-to-side anastomosis; external carotid artery to distal cervical vertebral artery end-to-end anastomosis; and occipital artery to posterior inferior cerebellar artery end-to-side anastomosis. Each case is used to demonstrate the evaluation and management involved, the type of and rationale for the surgical procedure selected, and the patency of the anastomosis performed. Two points are emphasized. One is that, after careful angiographic evaluation and improved perioperative medical management, lesions of the vertebral artery are indeed amenable to microsurgical intervention with relatively low risk to the patient. The other is that, whenever possible, anastomosis of the largest caliber of vessels with the least number of suture lines is the surgical treatment of choice.

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