scholarly journals The intracranial vasculature of canines represents a model for neurovascular ischemia and training residents and fellows in endovascular neurosurgery

2020 ◽  
Vol 33 (4) ◽  
pp. 292-296
Author(s):  
Xianli Lv ◽  
Chen Li ◽  
Weijian Jiang

Background We describe use of a canine model to evaluate physiological effects and neuroprotective strategies in the setting of cerebral ischemia and endovascular neurosurgery training. Methods We performed transfemoral digital subtraction cerebral and cervical angiography on eight anesthetized dogs. Angiographic images of cerebral arteries were obtained following cannulation of the femoral artery. Cerebral ischemia models were made after angiography. Results The canine cerebral vasculature exhibited extensive tortuosity of the carotid and vertebral arteries. Conversely, the bilateral anterior spinal arteries were easily catheterized using microcatheters and microguidewires. The basilar artery and its branches were facilely cannulable. Circle of Willis continuity sans hypoplasia or aplasia of its constitutive segments was appreciated in all animals. The middle cerebral arteries could be easily accessed via the posterior communicating arteries. We generated an empirically evaluable therapeutically interventional experimental animal model of cerebral ischemia by occluding the middle cerebral artery using small coils for a duration between 15 and 60 min. Conclusion Unique amenability of the canine intracranial vasculature to selective and microcatheter cannulation renders experimentally induced cerebral, cerebellar, and brainstem via occlusion of the supratentorial and infratentorial arteries a simple matter. The neural vasculature irrigating the canine cerebrum, brainstem, and cerebellum may consequently prove useful in helping young and nascent endovascular neurosurgeons in developing and refining their skills of microcatheter navigation and manipulation and deployment of therapeutic devices to achieve effective occlusion of aneurysms, arteriovenous malformations, arteriovenous fistulas, and neoplasms of the intracranial cavity.

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
A. Akyol ◽  
B. Nazliel ◽  
H. Z. Batur Caglayan ◽  
Y. Oner ◽  
G. Turkoz Sucak

A 47-year-old female with a prior history of POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome was admitted with transient ischemic attacks complicated by dysarthria and right-sided hemiparesis. A blood survey indicated thrombocytosis and hyperfibrinogenemia while imaging of intracranial vasculature showed occlusion of the bilateral middle cerebral arteries. POEMS syndrome, of which arterial thromboses have been mentioned as a manifestation, is rarely accompanied by transient ischemic attacks. The pathophysiologic mechanism is yet unclear and needs further investigation.


2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Mimmi Rehnström ◽  
Hilda Ahnstedt ◽  
Diana N. Krause ◽  
Marie Louise Edvinsson ◽  
Kristian Agmund Haanes ◽  
...  

1977 ◽  
Vol 46 (3) ◽  
pp. 296-303 ◽  
Author(s):  
Noboru Toda ◽  
Takashi Ozaki ◽  
Tomio Ohta

✓ In anesthetized dogs, subarachnoid hemorrhage (SAH) was induced by the mechanical rupture of the unilateral intracranial internal carotid artery. Vasospasm was angiographically determined 24 hours and 7 days after SAH. Contractile responses to serotonin, norepinephrine, histamine, and K+ were compared in control and bleeding sides of the middle cerebral arteries removed from dogs with SAH, and from sham-operated dogs. Under sham operation and 2 hours after SAH, responses in the arteries of both sides did not appreciably differ but response was significantly less in arteries from the bleeding side as compared with the control side 24 hours and 7 days after hemorrhage. However, median effective concentrations of serotonin, histamine, and K+ were approximately the same in the arteries from both sides. Vasospasm and decreased sensitivity to the vasoactive agents of middle cerebral arteries were reversed 42 days after SAH. It is thus quite likely that initiation and maintenance of post-hemorrhage vasospasm is not associated with an increase in the sensitivity of cerebral arteries to vasoconstricting endogenous substances, rather the state of decreased sensitivity of cerebral arteries in contact with SAH may be instrumental in relieving prolonged vasospasm.


Author(s):  
Novikova I.N. ◽  
Popova T.F. ◽  
Gribacheva I.A. ◽  
Petrova E.V. ◽  
Marushchak A.A. ◽  
...  

Moya-Moya disease is a rare progressive chronic cer-ebrovascular disease characterized by a narrowing of the lumen of the intracranial segments of the internal carotid arteries, as well as the initial segments of the anterior and middle cerebral arteries with the devel-opment of a network of small vascular anastomoses. Violations of blood supply due to occlusion lead to the development of ischemic strokes in the correspond-ing pools, and ruptures of vascular anastomoses - to the development of hemorrhagic strokes, causing a variety of neurological disorders. The article presents a clinical case of Moya-Moya disease in a 31-year-old patient. The disease was manifested by acute disorders of cerebral circulation in ischemic and hemorrhagic types. The diagnosis was made in accordance with the diagnostic criteria of the disease based on the data of endovascular cerebral angiography.


1993 ◽  
Vol 264 (4) ◽  
pp. H1245-H1250 ◽  
Author(s):  
J. E. Brian ◽  
R. H. Kennedy

This study was designed to further elucidate the role of the endothelium in regulation of cerebral vascular smooth muscle tone. Dose-dependent vasoconstrictive effects of serotonin (5-HT) were examined in endothelium-intact and endothelium-denuded ring segments prepared from canine basilar and middle cerebral arteries. Some preparations were pretreated with 10(-5) M N omega-nitro-L-arginine (L-NNA), an agent that inhibits the production of L-arginine-derived nitric oxide, one of the compounds proposed to be endothelium-derived relaxing factor. L-NNA alone elicited marked dose-dependent increases in tension in endothelium-intact preparations; a significantly smaller response was seen in endothelium-denuded preparations. The effects of L-NNA on endothelium-intact preparations were partially reversed by washing and treatment with L-arginine. The maximum tension induced by 5-HT was approximately doubled by removal of the endothelium as well as by L-NNA treatment of endothelium-intact preparations; a slight increase in maximum tension occurred in endothelium-denuded preparations treated with L-NNA. The concentration of 5-HT producing half-maximal contraction (ED50) was not affected by L-NNA. These data suggest that L-arginine-derived nitric oxide modulates canine cerebral arterial tone in both the resting state and during contraction with 5-HT.


2021 ◽  
Vol 11 (7) ◽  
pp. 874
Author(s):  
Sérgio Brasil ◽  
Fabio Silvio Taccone ◽  
Sâmia Yasin Wahys ◽  
Bruno Martins Tomazini ◽  
Filippo Annoni ◽  
...  

Introduction: One of the possible mechanisms by which the new coronavirus (SARS-Cov2) could induce brain damage is the impairment of cerebrovascular hemodynamics (CVH) and intracranial compliance (ICC) due to the elevation of intracranial pressure (ICP). The main objective of this study was to assess the presence of CVH and ICC alterations in patients with COVID-19 and evaluate their association with short-term clinical outcomes. Methods: Fifty consecutive critically ill COVID-19 patients were studied with transcranial Doppler (TCD) and non-invasive monitoring of ICC. Subjects were included upon ICU admission; CVH was evaluated using mean flow velocities in the middle cerebral arteries (mCBFV), pulsatility index (PI), and estimated cerebral perfusion pressure (eCPP), while ICC was assessed by using the P2/P1 ratio of the non-invasive ICP curve. A CVH/ICC score was computed using all these variables. The primary composite outcome was unsuccessful in weaning from respiratory support or death on day 7 (defined as UO). Results: At the first assessment (n = 50), only the P2/P1 ratio (median 1.20 [IQRs 1.00–1.28] vs. 1.00 [0.88–1.16]; p = 0.03) and eICP (14 [11–25] vs. 11 [7–15] mmHg; p = 0.01) were significantly higher among patients with an unfavorable outcome (UO) than others. Patients with UO had a significantly higher CVH/ICC score (9 [8–12] vs. 6 [5–7]; p < 0.001) than those with a favorable outcome; the area under the receiver operating curve (AUROC) for CVH/ICC score to predict UO was 0.86 (95% CIs 0.75–0.97); a score > 8.5 had 63 (46–77)% sensitivity and 87 (62–97)% specificity to predict UO. For those patients undergoing a second assessment (n = 29), after a median of 11 (5–31) days, all measured variables were similar between the two time-points. No differences in the measured variables between ICU non-survivors (n = 30) and survivors were observed. Conclusions: ICC impairment and CVH disturbances are often present in COVID-19 severe illness and could accurately predict an early poor outcome.


PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e113624 ◽  
Author(s):  
Anne-Sofie Grell ◽  
Rushani Thigarajah ◽  
Lars Edvinsson ◽  
Ajoy Kumar Samraj

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