Diagnosis and treatment of acute isolated proximal internal carotid artery occlusions: a narrative review

Abstract

The clinical manifestations of proximal (extracranial) internal carotid artery occlusions (pICAOs) may range from asymptomatic to acute, large, and devastating ischemic strokes. The etiology and pathophysiology of the occlusion, intracranial collateral status and patient’s premorbid status are among the factors determining the clinical presentation and outcome of pICAOs. Rapid and accurate diagnosis is crucial and may be assisted by the combination of carotid and transcranial duplex sonography, or a computed tomography/magnetic resonance angiography (CTA/MRA). It should be noted that with either imaging modalities, the discrimination of a pseudo-occlusion of the extracranial internal carotid artery (ICA) from a true pICAO may not be straightforward. In the absence of randomized data, the management of acute, symptomatic pICAOs remains individualized and relies largely on expert opinion. Administration of intravenous thrombolysis is reasonable and probably beneficial in the settings of acute ischemic stroke with early presentation. Unfortunately, rates of recanalization are rather low and acute interventional reperfusion therapies emerge as a potentially powerful therapeutic option for patients with persistent and severe symptoms. However, none of the pivotal clinical trials on mechanical thrombectomy for acute ischemic stroke randomized patients with isolated extracranial large vessel occlusions. On the contrary, several lines of evidence from non-randomized studies have shown that acute carotid endarterectomy, or endovascular thrombectomy/stenting of the ICA are feasible and safe, and pοtentially beneficial. The heterogeneity in the pathophysiology and clinical presentation of acute pICAOs renders patient selection for an acute interventional treatment a complicated decision-making process. The present narrative review will outline the pathophysiology, clinical presentation, diagnostic challenges, and possible treatment options for pICAOs.

Stenting for subclavian steal phenomenon to restore cerebral perfusion due to acute carotid occlusion following carotid endarterectomy: a case report

“…By contrast, even without stenting, it is possible that the patient’s symptoms may have improved with medical treatment. However, the recanalization rate of intravenous thrombolysis in the extracranial ICA was low at 14.6% [ 23 ], and thrombolysis was probably inappropriate after CEA. While induced hypertension of 170–200 mmHg may be effective [ 24 ], this patient was rather hypotensive, and maintenance of marked hypertension, as reported, would have been complex.…”

“…While induced hypertension of 170–200 mmHg may be effective [ 24 ], this patient was rather hypotensive, and maintenance of marked hypertension, as reported, would have been complex. Approximately half of symptomatic extracranial ICA occlusive diseases are reported to lead to moderate or severe stroke [ 23 ], suggesting that our patient would likely have had a poor outcome without endovascular revascularization. The outcomes of these possibilities remain difficult to determine because quantitative cerebral blood flow assessments, i.e., positron emission tomography, were unavailable in the emergent situation.…”

Diagnostic accuracy of large and medium vessel occlusions in acute stroke imaging by neurology residents and stroke fellows: A comparison of CT angiography alone and CT angiography with CT perfusion

“…33 Fast identification of an isolated proximal or distal ICA occlusion with patent intracranial arteries is crucial, as EVT may be considered for patients with severe stroke or when there is progression of neurological symptoms. [34][35][36] This high failure rate is difficult to understand and may reflect how trainees evaluate imaging in the acute setting, focusing mainly on the intracranial vessels, especially when there is reformatting of the intracranial internal carotid or middle cerebral arteries, as shown in Figure 1, example 1. Neuronal damage can occur very rapidly following LVO, especially in patients with poor collaterals.…”

The novel imaging methods in diagnosis and assessment of cerebrovascular diseases: an overview

“…CTA can help identify the underlying cause of stroke and guide appropriate treatment options. Additionally, CTA allows for preoperative planning in patients undergoing surgical interventions, such as carotid endarterectomy or aneurysm clipping ( 68 , 69 ). Besides, advanced CTA techniques, such as time-resolved CTA (4D-CTA), have improved the temporal resolution of CTA images, allowing for better assessment of dynamic vascular abnormalities and providing valuable information about the flow patterns within the blood vessels ( 70 , 71 ).…”