scholarly journals Hemodynamic Consideration of Intracranial Aneurysm

2017 ◽  
Vol 3 (4) ◽  
pp. 229-236
Author(s):  
Hiroshi Ujiie ◽  
Chie Shinohara ◽  
Yoshinori Tamano ◽  
Kouichi Katou ◽  
Akira Teramoto
Keyword(s):  
Fluid Dynamics ◽  
Blood Flow ◽  
Intracranial Aneurysm ◽  
Middle Cerebral Artery ◽  
Internal Carotid ◽  
Cerebral Aneurysms ◽  
Anterior Communicating Artery ◽  
Great Care ◽  
Wall Strength ◽  
Surgical Manipulation

We reviewed basic considerations in fluid dynamics of cerebral aneurysms and applied these in surgery on the three most common types: internal carotid-posterior communicating artery, middle cerebral artery, and anterior communicating artery. It was found that aneurysmal initiation and growth do not occur at symmetric bifurcations. As blood flow always obeys the law of inertia, jet flow into the aneurysm will disperse along the wall; assuming the aneurysmal wall strength is even, the shape of the aneurysm becomes round or oval. When neurosurgeons encounter an aneurysm that is not round or oval, the wall may be fragile and requires great care during surgical manipulation.

Tandem middle cerebral artery–internal carotid artery occlusions: reduced occlusion-to-revascularization time using a trans–anterior communicating artery approach with a Penumbra device

2012 ◽  
Vol 116 (3) ◽  
pp. 665-671 ◽  
Author(s):  
David J. Padalino ◽  
Eric M. Deshaies
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Internal Carotid ◽  
Ischemic Injury ◽  
Acute Onset ◽  
Anterior Communicating Artery ◽  
Scale Scores

Rapid revascularization of tandem extracranial and intracranial acute thromboembolic occlusions can be challenging and can delay restoration of blood flow to the cerebral circulation. Taking advantage of collateral pathways in the circle of Willis for thrombectomy can reduce the occlusion-to-revascularization time significantly, thereby protecting brain tissue from ischemic injury. The authors report using the trans–anterior communicating artery (ACoA) approach by using the Penumbra microcatheter to rapidly restore blood flow to the middle cerebral artery (MCA) territory prior to treating the ipsilateral internal carotid artery (ICA) occlusion. Two patients with acute onset of tandem ipsilateral ICA and MCA occlusions and a competent ACoA underwent rapid revascularization of the MCA using a trans-ACoA approach for pharmaceutical and mechanical thrombolysis with the 0.026-in Penumbra microcatheter. Subsequently, once blood flow was reestablished in the MCA territory via cross-filling from the contralateral ICA, the proximally occluded ICA dissection was revascularized with a stent. Both patients had rapid revascularization of the MCA territory (both Thrombolysis in Myocardial Infarction Grade 3) with the trans-ACoA approach (19 and 36 minutes) followed by treatment of the ipsilateral proximal ICA occlusion. This prevented prolonged MCA ischemia time (72 and 47 minutes for ICA revascularization time saved) that would have otherwise occurred if the dissections were treated prior to revascularization of the MCA. Both patients had improved NIH Stroke Scale scores after the procedure. No adverse events from crossing the ACoA with the Penumbra microcatheter were encountered during the revascularization procedure. The trans-ACoA approach with the Penumbra microcatheter for rapid revascularization of an acutely thrombosed MCA in the setting of a simultaneous ipsilateral proximal ICA occlusion is feasible in patients with a competent ACoA. This technique can significantly minimize ischemic injury by reducing the occlusion-to-revascularization time and allow for MCA perfusion via collateral circulation while treating a proximal occlusion. To the best of the authors' knowledge, this is the first reported trans-ACoA approach with the Penumbra microcatheter and the first to report the utilization of the collateral intracranial circulation to reduce occlusion-to-revascularization time.

The Perforating Branches of the Internal Carotid Artery: The Microsurgical Anatomy of Their Extracerebral Segments

Neurosurgery ◽  
1990 ◽  
Vol 26 (3) ◽  
pp. 472-479 ◽  
Author(s):  
Slobodan V. Marinkovié ◽  
Milan M. Milisavljevié ◽  
Zorica D. Marinkovié
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Cerebral Aneurysms ◽  
Microsurgical Anatomy ◽  
Great Care ◽  
Anterior Choroidal Artery ◽  
Frequent Site ◽  
Anterior Choroidal ◽  
Choroidal Artery

Abstract The perforating branches of the internal carotid artery (ICA) were examined in 30 forebrain hemispheres. These branches were present in all the cases studied, and varied from 1 to 6 in number (mean, 3.1). Their diameters ranged from 70 to 470 Mm (mean, 243 Mm). The perforating branches arose from the choroidal segment of the ICA, that is, from its caudal surface (52.3%), caudolateral surface (34.1%), or caudomedial surface (13.6%). They rarely originated from the bifurcation point of the ICA (10%). The distance of the remaining 90% of the perforators from the summit of the ICA measured between 0.6 and 4.6 mm. The perforating branches most often originated as individual vessels, and less frequently from a common stem with another vessel or by sharing the same origin site with another perforator or with the anterior choroidal artery. The bifurcation of the ICA, which is a frequent site for cerebral aneurysms, is surrounded by many perforating branches. Hence, great care must be taken to avoid damage to these important vessels during operations in that region.

Computational Fluid Dynamics Simulation of the Blood Flow in the Circle of Willis

2002 ◽  
Author(s):  
M. Harazawa ◽  
T. Yamaguchi
Keyword(s):  
Blood Flow ◽  
Blood Supply ◽  
Internal Carotid ◽  
Complex Geometry ◽  
Cerebral Aneurysms ◽  
Cerebrovascular Diseases ◽  
Circle Of Willis ◽  
Dynamics Simulation ◽  
The Brain ◽  
Internal Carotid Arteries

The blood supply for the brain is born by four arteries, that is, two internal carotid arteries and two vertebral arteries. They are mutually connected at the cerebral base, and form a closed arterial circle, called the circle of Willis, so that the safety of the brain blood supply is increased. However their anastomoses show a very wide variety of atypism. If some of anastomses are very thin, or even do not exist, the safety of the blood supply is not secured. This is particularly important when some diseases such as cerebral thrombosis occurs and the blood flow supply stops unilaterally. Redistribution of the blood supply in such cases is thought to be strongly affected by geometrical configuration of the anastomoses. It is also known that cerebral aneurysms, which may induce serious cerebrovascular diseases, preferentially occur at the circle of Willis. Complex blood flow pattern has been suspected of having an influence on this preference. This is again dependent on complex geometry of the circle.

scholarly journals A Workflow for Patient-Individualized Virtual Angiogram Generation Based on CFD Simulation

2012 ◽  
Vol 2012 ◽  
pp. 1-24 ◽  
Author(s):  
Jürgen Endres ◽  
Markus Kowarschik ◽  
Thomas Redel ◽  
Puneet Sharma ◽  
Viorel Mihalef ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Blood Flow ◽  
Shear Stress ◽  
Cfd Simulation ◽  
Cerebral Aneurysms ◽  
Patient Specific ◽  
Hemodynamic Parameters ◽  
Risk Of Rupture ◽  
Computational Fluid Dynamics Cfd ◽  
Subsequent Comparison

Increasing interest is drawn on hemodynamic parameters for classifying the risk of rupture as well as treatment planning of cerebral aneurysms. A proposed method to obtain quantities such as wall shear stress, pressure, and blood flow velocity is to numerically simulate the blood flow using computational fluid dynamics (CFD) methods. For the validation of those calculated quantities, virtually generated angiograms, based on the CFD results, are increasingly used for a subsequent comparison with real, acquired angiograms. For the generation of virtual angiograms, several patient-specific parameters have to be incorporated to obtain virtual angiograms which match the acquired angiograms as best as possible. For this purpose, a workflow is presented and demonstrated involving multiple phantom and patient cases.

Superficial Temporal Artery-Middle Cerebral Artery Bypass Using a Thick STA after Endarterectomy: A Rescue Technique

2017 ◽  
Vol 78 (06) ◽  
pp. 595-600 ◽  
Author(s):  
Akira Tamase ◽  
Tomoya Kamide ◽  
Kentaro Mori ◽  
Syunsuke Seki ◽  
Yu Iida ◽  
...  
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Internal Carotid ◽  
Artery Bypass ◽  
Superficial Temporal Artery ◽  
Temporal Artery ◽  
Rescue Technique ◽  
Size Discrepancy ◽  
Thickened Intima

Background and Objective Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass is a procedure to reconstruct cerebral blood flow in the MCA territory. In some cases, the STA wall is thickened and the size discrepancy between STA and MCA is apparent. In such a situation, STA-MCA bypass is challenging. We present two patients who underwent STA-MCA bypass using STA in which a thickened intima was removed. We discuss the usefulness of this rescue technique. Patients and Results A patient with an atherosclerotic MCA occlusion and another with an occluded internal carotid artery are included. Endarterectomy of STA was performed before or during anastomosis, and the intima-resected STA was anastomosed to MCA. In both cases, the STA was thick and hard, and it was difficult to anastomose the STA as it was to the MCA. Patency of the bypass was confirmed by postoperative angiography. Conclusion Endarterectomy of a thickened STA might be an effective rescue technique in cases with severely atherosclerotic STA in STA-MCA bypass.

Cerebral Blood Flow After Surgery for Unruptured Cerebral Aneurysms: Effects of Surgical Manipulation and Irrigation Fluid

Neurosurgery ◽  
2011 ◽  
Vol 69 (3) ◽  
pp. 677-688 ◽  
Author(s):  
Hiroaki Shimizu ◽  
Takashi Inoue ◽  
Miki Fujimura ◽  
Atsushi Saito ◽  
Teiji Tominaga
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Inferior Frontal Gyrus ◽  
Cerebral Aneurysms ◽  
Physiological Saline ◽  
Cerebrovascular Diseases ◽  
Irrigation Fluid ◽  
Unruptured Cerebral Aneurysms ◽  
Clinical Conditions ◽  
Surgical Manipulation

Abstract BACKGROUND: Cerebral blood flow (CBF) is important in the management of cerebrovascular diseases. Surgical manipulation may compromise the appropriate interpretation of postoperative CBF changes, but the effects are not well understood. Objective: To investigate the effect of surgical manipulation on postoperative CBF in a setting of prospective randomized comparison of 2 irrigation fluids during surgery. Methods: Twenty patients undergoing the clipping of unruptured cerebral aneurysms through the pterional approach were randomly assigned to use of Artcereb, an artificial cerebrospinal fluid, or physiological saline as irrigation fluid. Postoperative CBF and clinical conditions were evaluated 3 times in the first 7 to 10 postoperative days. Results: Postoperative CBF decreased by 10 to 15% on the first postoperative day in the ipsilateral inferior frontal gyrus, where surgical manipulation may be greatest. CBF reduction was less in regions remote from the surgical site and later in the follow-up periods. Selection of irrigation fluid did not influence postoperative CBF significantly, although postoperative clinical conditions may be better using Artcereb. Conclusion: Postoperative CBF changes due to surgical manipulation should be considered in patients whose hemodynamic conditions are important for appropriate management.

scholarly journals Transcirculation Pipeline embolization device deployment: a rescue technique

2017 ◽  
Vol 42 (6) ◽  
pp. E13 ◽  
Author(s):  
Edison P. Valle-Giler ◽  
Elias Atallah ◽  
Stavropoula Tjoumakaris ◽  
Robert H. Rosenwasser ◽  
Pascal Jabbour
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Cerebral Aneurysms ◽  
Artery Aneurysm ◽  
Carotid Artery Dissection ◽  
Artery Dissection ◽  
Anterior Communicating Artery ◽  
Pipeline Embolization Device ◽  
Contralateral Internal Carotid Artery

The Pipeline embolization device (PED) has become a very important tool in the treatment of nonruptured cerebral aneurysms. However, a patient’s difficult anatomy or vascular stenosis may affect the device delivery. The purpose of this article was to describe an alternate technique for PED deployment when ipsilateral anatomy is not amenable for catheter navigation.A 44-year-old woman with a symptomatic 6-mm right superior hypophyseal artery aneurysm and a known history of right internal carotid artery dissection presented for PED treatment of her aneurysm. An angiogram showed persistence of the arterial dissection with luminal stenosis after 6 months of dual antiplatelet treatment. The contralateral internal carotid artery was catheterized and the PED was deployed via a transcirculation approach, using the anterior communicating artery. Transcirculation deployment of a PED is a viable option when ipsilateral anatomy is difficult or contraindicated for this treatment.

The transition from hunterian ligation to intracranial aneurysm clips: a historical perspective

2006 ◽  
Vol 20 (6) ◽  
pp. 1-7 ◽  
Author(s):  
Nika V. Polevaya ◽  
M. Yashar S. Kalani ◽  
Gary K. Steinberg ◽  
Victor C. K. Tse
Keyword(s):  
Intracranial Aneurysm ◽  
Historical Perspective ◽  
Conservative Therapy ◽  
Internal Carotid ◽  
Driving Forces ◽  
Treatment Options ◽  
Cerebral Aneurysms ◽  
Coil Occlusion ◽  
Modern Era ◽  
Direct Placement

✓ The description of cerebral aneurysms dates back to antiquity. Little was known, however, about the pathological mechanisms of aneurysm formation and treatment options for this disease until 200 years ago. The modern era of aneurysm treatment began with the hunterian ligation of the proximal artery, followed by clip and coil occlusion. In this article, the authors describe the transition from conservative therapy to internal carotid artery (ICA) ligation and gradual occlusion of the ICA to the direct placement of clips on aneurysms. The driving forces and rationale behind each major advancement are summarized, and the authors attempt to predict what these innovations mean for the future of intracranial aneurysm management.

The incidence and treatment of asymptomatic, unruptured cerebral aneurysms

1994 ◽  
Vol 80 (2) ◽  
pp. 217-223 ◽  
Author(s):  
Toshio Nakagawa ◽  
Kazuo Hashi
Keyword(s):  
Early Detection ◽  
Internal Carotid ◽  
Cerebral Aneurysms ◽  
Maximum Diameter ◽  
Anterior Communicating Artery ◽  
Content Type ◽  
Unruptured Aneurysms ◽  
Unruptured Intracranial Aneurysms ◽  
History Of ◽  
Unruptured Cerebral Aneurysms

✓ The importance of early detection by various radiological techniques of asymptomatic, unruptured aneurysms as a means of preventing subarachnoid hemorrhage (SAH) is discussed in this report. Four hundred volunteers underwent clinical and radiological evaluations between March, 1988, and September, 1992. Studies included a neurological examination as well as digital subtraction cerebral angiography via a femoral arterial catheter, computerized tomography, T1- and T2-weighted magnetic resonance (MR) imaging of the whole brain, and MR angiography. The evaluation revealed 27 asymptomatic, unruptured intracranial aneurysms in 26 volunteers, for an incidence of 6.5%. The subjects ranged in age from 39 to 71 years, with an average of 55 years. The aneurysms were located on the internal carotid artery in 13 cases (48%), the anterior communicating artery in six (22%), the middle cerebral artery in six (22%), and the basilar artery in two (7%). Aneurysms ranged in size from 5 mm or less in 16 cases, 6 to 10 mm in nine, and 11 to 15 mm in one; one aneurysm was more than 15 mm, with a maximum diameter of 2 cm. Volunteers with a family history of SAH within the second degree of consanguinity showed a higher incidence of aneurysms (17.9%). Aneurysm clipping was performed on 20 of the 26 cases with no significant morbidity or mortality. These findings support the contention that aggressive early detection of unruptured aneurysms may improve the outcome in patients harboring cerebral aneurysms by preventing the devastating effects of SAH.

Sign in / Sign up

Export Citation Format

Share Document