Nonlinear biomechanical behaviour of extracranial carotid artery aneurysms in the framework of Windkessel effect via FSI technique.

Extracranial carotid artery aneurysms (ECCA) lead to rupture and neurologic symptoms from embolisation, with potentially fatal outcomes. Investigating the biomechanical behaviour of EECA with blood flow dynamics is crucial for identifying regions more susceptible to rupture. A coupled three-dimensional (3D) Windkessel-framework and hyperelastic fluid-structure interaction (FSI) analysis of ECCAs with patient-specific geometries, was developed in this paper with a particular focus on hemodynamic parameters and the arterial wall's biomechanical response. The blood flow has been modelled as non-Newtonian, pulsatile, and turbulent. The biomechanical characteristics of the aneurysm and artery are characterised employing a 5-parameter Mooney-Rivlin hyperelasticity model. The Windkessel effect is also considered to efficiently simulate pressure profile of the outlets and to capture the dynamic changes over the cardiac cycle. The study found the aneurysm carotid artery exhibited the high levels of pressure, wall shear stress (WSS), oscillatory shear index (OSI), and relative residence time (RRT) compared to the healthy one. The deformation of the arterial wall and the corresponding von Mises (VM) stress were found significantly increased in aneurysm cases, in comparison to that of no aneurysm cases, which strongly correlated with the hemodynamic characteristics of the blood flow and the geometric features of the aneurysms. This escalation would intensify the risk of aneurysm wall rupture. These findings have critical implications for enhancing treatment strategies for patients with extracranial aneurysms.

Giant cell arteritis as a cause of extracranial internal carotid artery aneurysm: a case report.

BACKGROUND: This report presents the management of patient with extracranial internal carotid artery pseudoaneurysm due to giant cell arteritis. CASE PRESENTATION: Left internal carotid artery pseudoaneurysm was diagnosed in a 57-year-old Ukrainian woman, which became a direct indication for surgical treatment involving aneurysm resection and internal carotid artery reimplantation. The used reconstruction technique with oblique cutting of internal carotid artery, aneurysm resection, ellipse-form anastomosis formation, and distal intima fixation prevents the dissection, restenosis, and aneurysm of anastomosis in the long-term postoperative period. Histopathological examination revealed the giant cell arteritis of the internal carotid artery. CONCLUSION: This case emphasizes the importance of open surgical treatment of extracranial carotid artery aneurysms, which allows to perform optimal carotid artery reconstruction and also define the rare etiology of disease.

Extracranial internal carotid aneurysm treated with a covered stent in an infant.

BACKGROUND: Extracranial internal carotid aneurysms consist a rare pathology with an overall incidence less than 1% in the general population, and warrant treatment due to their association with cerebrovascular events and neurological complications. The incidence is even lower in the pediatric population. CASE REPORT: A 14-month infant presented in our clinic with neck swelling of unknown origin, with subsequent MR imaging revealing an extracranial internal carotid aneurysm. Due to the patient's age and risk of surgical complications, the decision to proceed with endovascular repair with stent placement and complete exclusion of the aneurysm from the circulation was made, after multidisciplinary consultation. RESULTS: In the pediatric population, pediatric population, endovascular stent placement can be considered at least as a last resort treatment when surgical access harbors significant risks or is impossible.

Extracranial Internal Carotid Aneurysm Manifesting With Tinnitus: A Rare Presentation.

A 19-year-old male presented with a history of pulsatile tinnitus on the left side after he underwent drainage for a tonsillar swelling. He had noticed a painless neck swelling one month ago that was associated with difficulty in swallowing. His physician had made a diagnosis of peritonsillar abscess, and drainage had been performed. After the procedure, the swelling had progressed further, leading to drooling of saliva and disabling tinnitus. When he presented to the emergency, local examination revealed a pulsatile neck swelling with peritonsillar mass. CT angiography/digital subtraction angiography (DSA) of the neck and brain revealed a large aneurysm of the distal cervical segment of the left internal carotid artery (ICA). The patient successfully underwent an urgent open repair. This case highlights the importance of a thorough history and examination in identifying a rare cause of pulsatile tinnitus. A stepwise approach to determine the reason behind tinnitus revealed an underlying ICA aneurysm of the extracranial segment.

Extracranial Internal Carotid Artery Aneurysm in Pregnancy.

Isolated extracranial internal carotid artery aneurysms (EICAAs) are rare, accounting for only about .4-4% of all peripheral artery aneurysms. We present a case of an EICAA in a young pregnant patient. To our knowledge, this is the first case being reported of a true EICAA during pregnancy in a multiparous woman. A 25-year-old pregnant patient presented with a pulsatile left neck swelling. Radiological investigations and subsequent surgery during the first trimester confirmed a true saccular left ICA with a maximum diameter of 3.5 cm. She was treated with aneurysm excision and primary anastomosis. She did not have any underlying diseases predisposing to an EICAA. She has been well for 3 years post procedure. It has been postulated that pregnancy could lead to aneurysm development through multiple mechanisms, including hemodynamic, hormonal, and other physiologic changes of pregnancy. Aggressive treatment with surgical intervention is advocated because of the risk of cerebral ischemic complications associated with non-operative treatment, and because satisfactory long-term outcomes can be achieved from surgery.

"Extra-cranial proximal pica aneurysm - a rare and surreptious cause of posterior fossa sah: case report and review of literature".

BACKGROUND: Extra-cranial posterior inferior cerebellar artery (PICA) aneurysms are rare with only 22 cases been reported so far. Intra-dural type of extra-cranial PICA aneurysm is even rarer with few case reports available. We report a previously unreported type of proximal PICA aneurysm in which the PICA aneurysm had intra-dural location at the C2 vertebral level. CASE DESCRIPTION: A 51 year old gentleman presented with sub-arachnoid haemorrhage and intra-ventricular haemorrhage, predominantly involving the fourth ventricle and had no focal neurological deficit. CT angiogram was negative however a dedicated four vessel angiogram demonstrated an abnormal extracranial origin of right PICA at C1-C2 level, with associated aneurysm in its proximal segment. A C1 posterior arch excision with partial C2 laminectomy and clipping of the aneurysm was done. CONCLUSION: Aneurysm associated with extracranial intra-dural PICA origin is a rare cause of SAH, and may not be detected with CT angiography. Such cases often require dedicated four vessel angiography, with careful study for any possibility of extra-cranial aneurysm. This variant has important surgical implication and requires preservation of the Lateral spinal artery (LSA-PICA communication), and that such aneurysm approached only with posterior cervical exposure without the need of a craniotomy. Such cases remind us the need to have an in-depth understanding of the variations of the posterior circulation.

Management of an extracranial internal carotid artery aneurysm secondary to relapsing polychondritis.

Extracranial internal carotid artery (EICA) aneurysms make up 1% of peripheral aneurysms and less than 1% of patients who have relapsing polychondritis develop aneurysms. A 39-year-old man with relapsing polychondritis presented with right neck pain. Initial computed tomography angiography demonstrated a 16-mm right EICA aneurysm with growth to 25 mm after 2 months. A right EICA aneurysmectomy, external carotid artery to ICA transposition, and internal jugular vein patch of the common carotid artery was performed with symptom resolution. The inflammatory nature of the underlying disease, aggressive expansion, and symptomatic state warranted open repair and we recommend life-long monitoring given the rarity of this case.

Surgical management of internal carotid artery aneurysm near the skull base.

Extracranial carotid artery aneurysms are rare. The most common location is the common carotid artery near the bifurcation. The mid to distal internal carotid artery is the second most common location. We are reporting the case of a 64-year-old woman who was admitted to our department for management of an asymptomatic left internal carotid artery aneurysm. Physical examination revealed a pulsatile mass, and imaging confirmed the aneurysm diagnosis. Computed tomography angiography detailed a 28mm×3cm×6cm aneurysm of the left cervical internal carotid artery with tortuous outflow the aneurysm sac. Open repair was undertaken. Exposure with incision anterior to the sternocleidomastoid was performed although extended more superiorly than usual because of the distal aneurysm location. After carotid clamping, the aneurysm was resected and an end-to-end anastomosis with prosthesis was performed. After closure, the patient was extubated demonstrating baseline neurologic function. Histologic examination of the arterial wall confirmed the diagnosis of fibromuscular dysplasia.

Extracranial Aneurysms in 2 Patients with Autosomal Recessive Polycystic Kidney Disease.

Unlike autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD) is not generally known to be associated with vascular abnormalities. Only 4 cases of ARPKD patients with intracranial aneurysms have been reported previously. We present 2 ARPKD patients with extracranial vascular abnormalities: a young man with infrarenal aortic and iliac artery aneurysms complicated by dissection and a teenage girl with multiple splenic and gastric artery aneurysms and arterial vascular malformations. These cases raise the question of whether vascular integrity and development may be impaired in ARPKD, perhaps through molecular mechanisms overlapping with ADPKD. This possibility is supported by studies in mice that show ARPKD gene expression in the walls of large blood vessels.

Extracranially located PICA aneurysm presenting with supratentorial IVH: A rare event with diagnostic pitfalls.

Extracranially located posterior inferior cerebellar artery (PICA) aneurysms are rare with only 21 cases reported till date. They may arise either from the proximal segment of an extracranially originating PICA or from the tip of its caudal loop when it dips below the foramen magnum. A 16-year-old female presenting with sudden onset severe headache and intraventricular hemorrhage (IVH) in the occipital horns of the lateral ventricle and the fourth ventricles, was diagnosed to have an extracranial proximal segment PICA aneurysm on a four vessel digital subtraction angiography (DSA), after initially missing it on the brain magnetic resonance imaging (MRI) with angiogram (MRA) because of its extracranial location. During surgery, the aneurysm was clipped following a far lateral suboccipital craniectomy with C1-C2 hemilaminectomy. The patient showed good recovery. Thus, we emphasize the need for a dedicated four vessel angiography to diagnose such lesions.

Multiple Cerebral Aneurysms Associated with Extracranial Carotid Aneurysm: Case Report

We report a rare case of multiple cerebral aneurysms associated with an extracranial internal carotid aneurysm. This 59-year-old woman had a history of hypertension and a stroke. Brain CT scan and angiographic findings are presented.