Symptomatic Internal Carotid Artery Occlusion Research Articles

Symptomatic Internal Carotid Artery Occlusion: A Long-Term Follow-Up Study

In patients with minor stroke or transient ischemic attack (TIA) and internal carotid artery (ICA) occlusion, recurrent ischemic stroke is infrequent compared to other vascular events and is dependent upon clinical factors and the presence of leptomeningeal collaterals.

Carotid endarterectomy for symptomatic complete occlusion of the internal carotid artery.

We described 9 consecutive patients who underwent operative carotid artery exploration with attempted carotid endarterectomy (CEA) for symptomatic internal carotid artery (ICA) occlusion. Indications for this surgery based on vascular imaging included segmental occlusion of the proximal ICA and also extensive occlusion of the distal ICA in selected patients in whom color-flow duplex ultrasound showed a poorly echogenic or anechoic thrombus with a flow void, suggestive of an acute thrombus. CEA was performed successfully to restore blood flow in all 9 patients:CEA in 5 and CEA with Fogarty thrombectomy in 4. Postoperative magnetic resonance (MR) angiography confirmed that revascularization had been successful in all 9 patients, and MR imaging displayed improved perfusion in 4 patients. Despite the lack of a generalized efficacy of surgical revascularization for symptomatic ICA occlusion, our study demonstrated that preoperative vascular imaging allows the selection of patients who may benefit from CEA.

Short-Term Outcomes After Symptomatic Internal Carotid Artery Occlusion

Previous studies concerning internal carotid artery (ICA) occlusion have focused on long-term prognosis. The purpose of the present study was to evaluate short-term outcomes of patients with symptomatic ICA occlusion. We used data from the Registry of the Canadian Stroke Network on consecutive patients presenting to 11 stroke centers in Ontario. We included patients with noncardioembolic ischemic stroke or transient ischemic attack within the anterior circulation. The resulting cohort was divided into 4 groups based on vascular imaging of the ipsilateral extracranial ICA: occlusion, severe stenosis, moderate stenosis, and mild/no stenosis. Logistic regression modeling was used to evaluate the association between the degree of stenosis/occlusion of the symptomatic ICA and a series of short-term outcome measures. Of the 4144 patients who met study criteria, 283 patients had a symptomatic ICA occlusion. Compared with patients with ICA occlusion, patients with all other degrees of stenosis had a lower risk of in-hospital death, neurological worsening, and poor functional outcome. Particularly, severe stenosis was associated with a lower risk of in-hospital death (adjusted OR, 0.40; 95% CI, 0.20 to 0.79), neurological worsening (adjusted OR, 0.52; 95% CI, 0.34 to 0.78), and poor functional outcome (adjusted OR, 0.62; 95% CI, 0.41 to 0.94) compared with the ICA occlusion group. The results of our study showed that patients with symptomatic ICA occlusion are at a high risk of adverse outcomes that is as severe, if not worse, than any other degree of ICA stenosis in the short term. Thus, more aggressive management may be warranted for patients with acute, symptomatic ICA occlusion.

Prognostic Relevance of Limb Shaking in Symptomatic Carotid Artery Occlusion

Background: Internal carotid artery (ICA) occlusion, present in up to 15% of stroke patients, may cause low-flow transient ischemic attacks (TIAs) like limb shaking (LS) or retinal claudication (RC). Reliable data on the frequency of these phenomena and their potential prognostic relevance are still sparse. Aims: To provide more data about the frequency of low-flow TIA and investigate their influence on outcome. Material and Methods: Medical records of 260 consecutive patients with symptomatic ICA occlusion were carefully reviewed (survey period: January 2000 to December 2006). Baseline stroke severity and outcome at 90 days and in the long term were assessed. All patients were specifically questioned about symptoms of LS and RC, were exposed to bright light (pupillary testing) and carefully watched during testing of posture/gait and early mobilization. Results: LS, RC or both occurred in 28.6, 9.5 and 2.7%, respectively, of patients eligible for a thorough assessment of low-flow TIAs (n = 147). An adverse outcome was more likely in patients with LS than in those without at day 90 (modified Ranking Scale ≧4, 45.2 vs. 21.9%, p = 0.005) and in the long term (median, 37 months) (52.7 vs. 23.1%, p < 0.001). In a multivariable analysis, prognostic relevance was found to be independent of baseline stroke severity (National Institutes of Health Stroke Scale). There was also a tendency towards higher rates of recurrent stroke and TIA in limb shakers. RC had no prognostic relevance regarding functional outcome and recurrent events. Conclusion: In patients with ICA occlusion, RC and LS are more common than previously assumed. The presence of LS is associated with a worse outcome independent of initial stroke severity and patient characteristics.

Decreased hyperintense vessels on FLAIR images after endovascular recanalization of symptomatic internal carotid artery occlusion

Hyperintense vessels (HV) on fluid-attenuated inversion recovery (FLAIR) images were assumed to be explained by slow antegrade or retrograde leptomeningeal collateral flow related to extracranial or intracranial artery steno-occlusion. The aim of this study was to investigate the effect of recanalization after endovascular therapy of symptomatic internal carotid artery (ICA) occlusion on the presence of HV. Eleven patients with symptomatic ICA occlusion were retrospectively enrolled. Changes in the HV on FLAIR images were examined in affected hemisphere of each patient after successful treatment with endovascular recanalization (angioplasty, n = 3; stent-assisted angioplasty, n = 8). The relationship between postoperative changes in the HV and Thrombolysis In Cerebral Ischemia (TICI) scale (I-III) was assessed. After operation, HV of the 11 affected hemispheres were showed to be decreased (n = 3) or disappeared (n = 8) in treated side. The median interval between pre- and postoperative MRI examinations was 97.0 h (range, from 69. to 48.7h). Of the 8 patients with disappeared HV, 7 achieved high TICI grade flow (III) and 1 had relatively low TICI grade flow (IIc) in treated side. However, all the 3 patients with decreased HV were found to be relatively low TICI grade flow (IIc). Our data indicate that endovascular recanalization of ICA occlusion was effective for decreasing HV. Postoperative decrease in HV can be considered as a marker for hemodynamic improvement.

Clinical implications of collateral middle cerebral artery flow in acute ischaemic stroke with internal carotid artery occlusion

The presence of collateral middle cerebral artery (MCA) flow via the primary collateral pathway is thought to protect against the progression of cerebral ischaemia. However, there have been few reports on early clinical outcomes according to the presence of collateral MCA flow in acute ischaemic stroke (AIS) with internal carotid artery (ICA) occlusion. Therefore, we sought to investigate the early clinical outcomes and lesion patterns according to the presence of collateral MCA flows in AIS with ICA occlusion. This is a retrospective study of patients with AIS with ICA occlusion consecutively admitted to our stroke center between October 2008 and March 2010. Patients were included if they were admitted within 12 h of symptom onset with AIS and symptomatic ICA occlusion. Collateral MCA flow was defined as the presence of MCA signals from proximal M1 to distal MCA branches ipsilateral to the ICA occlusion by magnetic resonance angiography. Early neurological deterioration (END) was defined as a 4-point increase in the National Institutes of Health Stroke Scale (NIHSS) score and persistent neurological deterioration for at least 24 h or newly developed neurological symptoms within 7 days. Sixty-five patients (42 men, 23 women) were finally included. Initial NIHSS scores were significantly lower, and favorable outcomes at 3 months were better in patients with collateral MCA flow than in those without (P < 0.001). Initial lesion patterns were different according to the collateral MCA flow. However, patients with mild AIS might more frequently deteriorate than those with moderate to severe AIS. In our study, collateral MCA flow reduced initial stroke severity and was associated with favorable outcomes at 3 months but did not seem to protect against END in mild AIS patients with ICA occlusion. Therefore, the results of this study suggest that mild AIS patients with ICA occlusion should be carefully managed because their conditions may deteriorate.

What is the Real Risk of Dislodging Thrombi During Endovascular Revascularization of a Proximal Internal Carotid Artery Occlusion?

There is a theoretical concern that a thrombus may be dislodged distally when crossing the occluded segment during recanalization of a complete occlusion. To assess the immediate postprocedural brain diffusion-weighted image (DWI) findings following endovascular recanalization using an embolic protection device for proximal internal carotid artery (ICA) occlusion. We retrospectively identified 12 patients who underwent stent implantation for sudden symptomatic occlusion of the proximal ICA. In 8 patients, no additional intracranial occlusions were identified. In 4 patients, an additional intracerebral thrombus was detected in the middle cerebral artery. Distal protection devices were used in all cases. We evaluated the presence and amount of retrieved embolic fragments in the distal protection devices. The incidence and location of postprocedural emboli were determined using DWI. Recanalization of the proximal ICA was achieved in all patients. After complete occlusion of the proximal ICA was demonstrated, primary passage of the embolic protection device through the occluded ICA was gently navigated in 7 patients. However, this was not possible in 5 patients. Three patients developed new lesions on postprocedural DWI. Of the 12 patients in which distal protection devices were used, debris was detected in 7 patients. In endovascular revascularization of proximal ICA occlusion, postprocedural emboli occur less frequently than reported in a systematic review of the DWI literature. The real risk of dislodging thrombi appears to be from plaque fragment mobilization by angioplasty, rather than from crossing an occluded segment.

Quantitative perfusion computed tomography measurements of cerebral hemodynamics: Correlation with digital subtraction angiography identified primary and secondary cerebral collaterals in internal carotid artery occlusive disease

The aim of the present study was to assess hemodynamic variations in symptomatic unilateral internal carotid artery occlusion (ICAO) patients with primary collateral flow via circle of Willis or secondary collateral flow via ophthalmic artery and/or leptomeningeal collaterals. Thirty-eight patients with a symptomatic unilateral ICAO were enrolled in the study. Based on digital subtraction angiography (DSA) findings, patients were classified into 2 groups: primary collateral (n = 14) and secondary collateral (n = 24) groups. Collateral flow hemodynamics were investigated with perfusion computed tomography (PCT) by measuring the cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP) in the hemispheres ipsilateral and contralateral to ICAO. Based on the measurements, the ipsilateral to contralateral ratio for each parameter was calculated and compared. Irrespective of the collateral patterns, ipsilateral CBF was not significantly different from that of the contralateral hemisphere (P = 0.285); ipsilateral CBV and TTP was significantly increased compared with those of the contralateral hemisphere (P=0.000 and P = 0.000 for CBV and TTP, respectively). Furthermore, patients with secondary collaterals had significantly larger ipsilateral-to-contralateral ratios for both CBV (rCBV, P = 0.0197) and TTP (rTTP, P = 0.000) than those of patients with only primary collaterals. These two groups showed no difference in ipsilateral-to-contralateral ratio for CBF (rCBF, P = 0.312). Patients with symptomatic unilateral ICAO in our study were in an autoregulatory vasodilatation status. Moreover, secondary collaterals in ICAO patients were correlated with ipsilateral CBV and delayed TTP that suggested severe hemodynamic impairment, presumably increasing the risk of ischemic events.

Cerebrovascular reactivity within perfusion territories in patients with an internal carotid artery occlusion

BackgroundArterial spin labelling (ASL) is an MRI technique for measuring perfusion at the brain tissue level. The aim of the study was to investigate cerebrovascular reactivity (CVR) at brain-tissue level...

External Carotid Artery Stenting to Treat Patients With Symptomatic Ipsilateral Internal Carotid Artery Occlusion: A Multicenter Case Series

External Carotid Artery Stenting to Treat Patients With Symptomatic Ipsilateral Internal Carotid Artery Occlusion: A Multicenter Case Series

External Carotid Artery Stenting to Treat Patients With Symptomatic Ipsilateral Internal Carotid Artery Occlusion: A Multicenter Case Series

Conclusion: Stenting of the external carotid artery (ECA) in the face of symptomatic ipsilateral internal carotid artery (ICA) occlusion can be effective in some patients to relieve ischemic symptoms. Summary: The ECA is a significant extracranial-to-intracranial collateral source for the brain when the ICA is occluded. It may contribute, under those circumstances, 10% to 15% of middle cerebral artery blood flow (Fearn SJ, et al, J Vasc Surg 2000;31:989-93). Chronic neurologic symptoms ipsilateral to the combination of a ICA occlusion and ECA stenosis may be due to emboli originating from the ECA, emboli from a stump of the ICA, or direct reduction of collateral perfusion (Street DL, et al, J Vasc Surg 1987;6:280-2; and Nano G, et al, Cardiovasc Internvent Radiol 2006;29:140-2). Surgical treatment of ECA stenosis is infrequently performed but is a well-known and recognized procedure. However, endovascular management of ECA stenosis with angioplasty and stenting is a rare procedure. For this report, the authors gathered data from five academic medical centers to identify patients who underwent ECA stenting after 1998 and correlated clinical data, procedural details, and follow-up results for analysis. Half the patients came from a single medical center, with no more than three patients from each of the other four contributing institutions. There were 12 patients with a median age of 66 years (range, 45-79 years). Of these, 11 had ECA stenosis ≥70%, and all had ipsilateral ICA occlusion. Symptoms included amaurosis fugax, stroke, and transient ischemic attack. After endovascular treatment, there was resolution of symptoms in five patients at a median follow-up of 26 months (range, 1-87; mean, 29 months). One patient's procedure was complicated by aphasia and contralateral hemiplegia. This patient also subsequently developed a contralateral stroke and died 4 months after the procedure. An additional patient developed ipsilateral TIAs 3 weeks after stenting and subsequently underwent an extracranial-to-intracranial bypass, with no further symptoms. There was no apparent symptomatic in-stent restenosis, although >50% in-stent restenosis was noted in two patients on follow-up. Comment: Stenting of the ECA is an unusual procedure. (The article actually has more authors, 14, than patients, 12!) The results are certainly not a mandate for ECA stenting for apparently symptomatic ECA stenosis. However, there are also no compelling data for open revascularization of the ECA. Revascularization of the ECA, whether by endovascular or open surgical treatment, is supported by nothing more than individual case series and is never likely to be supported by anything other than case series.

Symptomatic internal carotid artery occlusion: a long-term follow-up study

BackgroundInformation on outcome of patients with occlusion of the internal carotid artery (ICA) is limited by the short duration of follow-up and lack of haemodynamic studies on the brain.MethodsThe authors...

Response to Letter by Paraskevas et al

Response: In response to our article,1 Paraskevas et al suggest that “severe, but not moderate, carotid atherosclerosis may predict concomitant vascular disease in other arterial beds.” In their study,2 they found a significant association between symptomatic (stroke, transient ischemic attack, amaurosis fugax) internal carotid artery occlusion and symptomatic atherosclerotic disease in other vascular beds, including the coronary, vertebral, aortic, and peripheral arteries. In contrast, in our study, we found that in patients with acute stroke symptoms, significant atherosclerotic disease in the carotid arteries (>50% stenosis imaged on CT angiography) did not predict significant disease in the coronary, aortic, or vertebral arteries. Our findings challenge the need for extensive investigation into the presence of coronary disease in patients with stroke symptoms as well as the general concept that atherosclerotic disease tends most …

Limb-Shaking Transient Ischaemic Attacks in Patients With Internal Carotid Artery Occlusion: A Case-Control Study

Conclusion: Transient ischemic attacks (TIAs) marked by limb-shaking are associated with high-grade carotid stenosis or internal carotid artery occlusion and can be recognized by short duration and precipitation by rising or exercise. They are also accompanied frequently by paresis and indicate an impaired hemodynamic state of the brain. Summary: Case-reports have described limb-shaking as an unusual clinical feature of TIAs (Klijn CJ, et al [Neurology 2000; 55: 1806-12] and Firlik AD, et al [Neurosurgery 1996;39:607-11]). The limb-shaking characterizing these TIAs consists of brief, jerky, and coarse involuntary movements involving an arm or a leg and has been associated with high-grade stenosis or occlusion of the internal carotid artery (ICA). An unanswered question is whether patients with high-grade ICA stenosis or occlusion who have limb-shaking TIAs have a worse hemodynamic flow state than patients with ICA stenosis or occlusion who do not have limb-shaking TIAs. In this study the authors sought to describe clinical characteristics of limb-shaking in patients with TIAs or moderately disabling strokes associated with occlusion of the ICA. They also sought to investigate whether the hemodynamic state of the patients with limb-shaking is worse than in patients with symptomatic ICA occlusion without limb-shaking. The authors studied 34 patients (82% men; mean age, 62 ± 7 years) who had limb-shaking associated with ICA occlusion and 68 age-matched and sex-matched controls who had hemispheric TIAs or minor disabling strokes and ICA occlusion but who did not have limb-shaking. They investigated collateral pathways using contrast angiograms and also studied carbon dioxide reactivity measured by transcranial Doppler imaging. Limb-shaking TIAs were found to last <5 minutes and were often accompanied by paresis of the involved limb. Patients with limb-shaking TIAs compared with controls more frequently had symptoms precipitated by exercise or rising (odds ratio [OR], 14.2; 95% confidence interval [CI], 4.2-47.9). Patients with limb-shaking TIAs also more frequently had recurrent ischemic deficits after ICA occlusion before inclusion in this study (OR, 8.2; 95% CI, 2.3-29.3). Patients with limb-shaking TIA's also tended to have lower carbon dioxide reactivity (mean, 5% ± 16% vs 12% ± 17%; OR. 0.97 per 1% increase; 95% CI, 0.94-1.00). Patients with limb-shaking TIAs had a greater dependence on leptomeningeal collaterals (OR, 6.8; 95% CI, 2.0-22.7). Comment: Limb shaking as a manifestation of a TIA is a relatively unknown to most vascular surgeons. Most of these patients have ICA occlusion; 10% of patients with ICA occlusion will have limb-shaking TIAs. Some of these patients, however, have high-grade ICA stenosis rather than occlusion and therefore are of interest to the peripheral vascular surgeon. It is important to note that this particular form of TIA is likely hemodynamic and not embolic. Patients with limb-shaking TIAs undergoing carotid endarterectomy therefore, perhaps, should be strongly considered for shunting during the performance of the endarterectomy when technically feasible.

External Carotid Artery Stenting to Treat Patients With Symptomatic Ipsilateral Internal Carotid Artery Occlusion

The external carotid artery (ECA) anastomoses in many distal territories supplied by the internal carotid artery (ICA) and is an important source of collateral circulation to the brain. Stenosis of the ECA in ipsilateral ICA occlusion can produce ischemic sequelae. To examine the effectiveness of ECA stenting in treating symptomatic ipsilateral ICA occlusion. We retrospectively reviewed patient databases from 5 academic medical centers to identify all individuals who underwent ECA stenting after 1998. For all discovered cases, coinvestigators used a common submission form to harvest relevant demographic information, clinical data, procedural details, and follow-up results for further analysis. Twelve patients (median age, 66 years; range, 45-79 years) were identified for our cohort. Vessel disease involvement included severe ECA stenosis >or= 70% in 11 patients and ipsilateral ICA occlusion in all patients. Presenting symptoms included signs of transient ischemic attack, stroke, and amaurosis fugax. ECA stenting was associated with preservation of neurological status in 11 patients and resolution of symptoms in 5 patients at a median follow-up time of 26 months (range, 1-87 months; mean, 29 months). Symptomatic in-stent restenosis did not occur within any patient during the follow-up course. We found ECA stenting in symptomatic ipsilateral ICA disease to be a potentially effective strategy to preserve neurological function and to relieve ischemic symptoms. Further investigation with larger studies and longer follow-up periods is warranted to elucidate the true indications of this management strategy.

E-009 What is the real risk of dislodging thrombi during endovascular revascularization of a proximal internal carotid artery occlusion?

PurposeThere is a theoretical concern that a thrombus may be dislodged distally when crossing the occluded segment during recanalization of a complete occlusion. In the present study, we assessed the...

Endovascular recanalization of the completely occluded internal carotid artery using a flow reversal system at the subacute to chronic stage

The efficacy and pitfalls of endovascular recanalization were evaluated in cases of internal carotid artery (ICA) occlusion in the subacute to chronic stage. Fourteen cases (15 lesions) of symptomatic ICA occlusion with hemodynamic compromise or recurrent symptoms were treated at the subacute to chronic stage using an endovascular technique. The Parodi embolic protection system was used during the recanalization procedure to prevent embolic stroke by reversing the flow from the distal ICA to the common carotid artery. Recanalization of the occluded ICA was possible in 14 of 15 lesions. The occlusion points were 10 cervical ICAs and 4 petrous/cavernous ICAs in successfully recanalized cases. Ischemic symptoms disappeared completely after the treatment, and new ischemic symptoms did not appear related to the treated lesion. Single photon emission computed tomography findings demonstrated the improvement of hemodynamic compromise in all cases. One case showed right middle cerebral artery branch occlusion during the procedure, but this patient's neurological symptoms were stable due to preexisting hemiparesis. Endovascular recanalization was possible and effective in improving hemodynamic compromise. However, there are still several problems with this technique, such as hyperperfusion syndrome after recanalization, cerebral embolism during treatment, durability after treatment, and identification of the occlusion point before treatment. Endovascular recanalization using an embolic protection device can be considered as an alternative treatment for symptomatic ICA occlusion with hemodynamic compromise or refractoriness to antiplatelet therapy, even in the subacute to chronic stage of the illness.

Angioplasty and Stent Placement in Symptomatic Internal Carotid Occlusion

To report a series of patients with symptomatic internal carotid artery (ICA) occlusion treated with angioplasty and stents. From a consecutive series of 50 patients experiencing neurologic ischemic symptoms and shown by conventional ultrasonography (US) to have a total ICA occlusion, 16 patients (ages 45-79 years; mean, 63 y; 10 men) were selected between August 2006 to September 2008 to be treated with angioplasty based on discovery of an open ICA distal to the occlusion through contrast-enhanced echo Doppler imaging and/or multislice contrast computed tomography (CT). Angioplasty and stent placement were performed under cerebral protection. Follow-up duplex imaging was performed at 14 days and 3 months and every 6 months thereafter and CT follow-up was performed at 2-9 months; the mean follow-up period was 9.9 months. Lesion crossing and stent placement was successful in 13 of 16 patients. There were no deaths, conversions, cardiac complications, or major strokes. One patient had a transient mild hemiparesis in the upper limb, with total recovery in 3 months. At follow-up, all 13 patients with a good initial result remained with patent arterial lumens and resolution of neurologic ischemic symptoms. After 2-9 months, ICAs with a "string sign" had calibers close or equal to those of normal arteries. Angioplasty with stent placement is an effective treatment with a low morbidity rate for selected patients who continue to experience neurologic ischemic symptoms despite US findings of total occlusion of the ICA.

Treatment of Transiently Symptomatic Acute Internal Carotid Artery Occlusion: Learning from the Interventional Field

A 69-year-old man experienced left hemiparesis and confusion of sudden onset, followed by complete spontaneous recovery after about 20 minutes. When carotid ultrasound was performed in the neurovascular unit 12 hours later, an occluded right internal carotid artery was found. Transcranial ultrasound showed normal flow in the right middle and anterior cerebral arteries. How should he be treated?

Arterial spin labeling perfusion MRI at multiple delay times: a correlative study with H(2)(15)O positron emission tomography in patients with symptomatic carotid artery occlusion.

Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) with image acquisition at multiple inversion times is a noninvasive ASL technique able to compensate for spatial heterogeneities in transit times caused by collateral blood flow in patients with severe stenosis of the cerebropetal blood vessels. Our aim was to compare ASL-MRI and H(2)(15)O positron emission tomography (PET), the gold standard for cerebral blood flow (CBF) assessment, in patients with a symptomatic internal carotid artery (ICA) occlusion. Fourteen patients (63+/-14 years) with a symptomatic ICA occlusion underwent both ASL-MRI and H(2)(15)O PET. The ASL-MRI was performed using a pulsed STAR labeling technique at multiple inversion times within 7 days of the PET. The CBF was measured in the gray-matter of the anterior, middle and posterior cerebral artery, and white-matter. Both PET and ASL-MRI showed a significantly decreased CBF in the gray-matter of the middle cerebral artery in the hemisphere ipsilateral to the ICA occlusion. The average gray-matter CBF measured with ASL-MRI (71.8+/-4.3 mL/min/100 g) was higher (P<0.01) than measured with H(2)(15)O PET (43.1+/-1.0 mL/min/100 g). In conclusion, ASL-MRI at multiple TIs is capable of depicting areas of regions with low CBF in patients with an occlusion of the ICA, although a systematic overestimation of CBF relative to H(2)(15)O PET was noted.