Current understanding of chronic total occlusion of the internal carotid artery (Review)

Abstract

At present, there is limited understanding of chronic total occlusion (CTO) of the internal carotid artery (ICA). Therefore, the present report collected related cases from PubMed and reviewed the literature. Cerebral vessels may form collateral circulation immediately or gradually following CTO of the ICA. The natural history of CTO of the ICA includes a variety of outcomes, all of which are biased toward a non-benign progressive process and are characterized by insufficient cerebral perfusion, embolus detachment and cognitive dysfunction. The majority of cases of CTO of the ICA require treatment. In early studies, the results of external-ICA bypass were unsatisfactory, while recanalization is now considered the only viable option. The current treatment indications mainly depend on the degree of injury to the cerebrovascular reserve and the extent to which the oxygen extraction fraction is increased. The length, height and duration of ICA occlusion are also relevant, though more frequently, the condition depends on multiple factors. Endovascular interventional recanalization, carotid endarterectomy (CEA) and hybrid surgery may be conducted in a select group of patients. As novel materials are developed, the success rate of simple recanalization may gradually increase; however, hybrid surgery may be more representative of the current trend, as advanced CEA can remove carotid atherosclerosis plaques, thus reducing the technological demands of the subsequent interventional recanalization. There are many complications that may result from recanalization following CTO of the ICA, including hyperperfusion and technical errors; therefore, the operation must be conducted carefully. If the recanalization is successful, it typically results in a stable improvement of patient condition in the long term. However, despite these conclusions, more studies are required in the future to further improve current understanding of CTO of the ICA.

Asymptomatic Complete Occlusion of Extracranial Internal Carotid Artery: A Case Report

“…Удлиненным считается отросток протяженностью >2.5 см. Такие отростки встречаются примерно у 4% людей из общей популяции и в 4% случаев, преимущественно у пациентов старше 30 лет, их присутствие сопровождается клинической симптоматикой [10]. При этом по данным Ayyildiz et al [11] средняя передняя длина отростка у пациентов с шилоподъязычным синдромом (синдромом Игла-Стерлинга) составляет 41.45 мм справа и 36.07 мм слева.…”

Mitophagy in Cerebral Ischemia and Ischemia/Reperfusion Injury

“…Surgical approaches like endarterectomy and stenting can also be used in treating chronic occlusion, though they still show some seeming drawbacks. Like in acute occlusion, endarterectomy might fail in cases with complex clot organization, and the successful rate of recanalization only achieves 40% in patients with chronic occlusion ( Thompson et al, 1986 ; Xu et al, 2018 ). Hypoperfusion still occurs in patients who have failed to restore blood flow in recanalization therapies, which is presumed to result in the recurrence of ischemic events ( Grubb et al, 1998 ).…”

“…Hypoperfusion still occurs in patients who have failed to restore blood flow in recanalization therapies, which is presumed to result in the recurrence of ischemic events ( Grubb et al, 1998 ). Also, in the process of stenting, the clot may detach when the stent is released, blocking the intracranial artery and may therefore causing post-operative complications ( Xu et al, 2018 ).…”

Carotid occlusion: Impact of cerebral hemodynamic impairment on cognitive performances

“…Intracranial circle reacts to CO with different mechanisms including activation of cerebral collaterals and microvessels dilatation to compensate the reduction of perfusion pressure. 1,2 This altered cerebral hemodynamic status has been associated to an increased predisposition to stroke. 3,4 Inflammatory pathways seem to be relevant in the development and destabilization of atherosclerotic processes.…”

“…Chronic occlusion of common or internal carotid arteries (CO) is able to induce a re‐organization of cerebral hemodynamic status. Intracranial circle reacts to CO with different mechanisms including activation of cerebral collaterals and microvessels dilatation to compensate the reduction of perfusion pressure 1,2 . This altered cerebral hemodynamic status has been associated to an increased predisposition to stroke 3,4 …”