Chronic Internal Carotid Artery Research Articles

Endovascular prevention and treatment of stroke related to extracranial carotid artery disease.

Acute ischemic stroke (AIS) is the leading cause of premature mortality and morbidity worldwide for both men and women. Extracranial carotid artery stenosis/occlusion is responsible for approximately 11.5% of ischemic strokes, whereas extracranial large vessel disease comprises roughly 16.6% of ischemic strokes. Carotid artery disease has been the source of significant debate among neurovascular and cardiovascular specialists, as well as vascular surgeons, as to the best method of revascularization, surgical reconstruction versus endovascular recanalization. There are different treatment modalities and techniques related to AIS and extracranial carotid artery disease based on the different etiologies, and these include acute internal carotid artery occlusion (thrombectomy versus carotid stenting/angioplasty), tandem occlusions (stenting and thrombectomy), and non-emergent carotid stenting/angioplasty for chronic internal carotid artery stenosis. The continuing development of new endovascular technology has led to a major shift in treatment to a minimally invasive endovascular approach. Distal filter devices, proximal protection devices, balloon-guided catheters, open- or closed-cell stents, and flow-reversal stenting are some of the technologies that are now available. The latest treatment techniques, indications, and studies are discussed in this review.

Angiographic Correlates of Cerebral Hemodynamic Changes With Diamox Challenge Assessed by Quantitative Magnetic Resonance Angiography.

Impaired cerebrovascular reserve in chronic steno-occlusive disease has been shown to be associated with poor leptomeningeal collaterals (LMCs) on digital subtraction angiography and increased stroke risk. We examined the relationship between the degree of LMCs and the flow change with Diamox challenge measured using quantitative magnetic resonance angiography (QMRA). Patients with steno-occlusion in the internal carotid artery or middle cerebral artery (MCA) at our institution between 2007 and 2013 were retrospectively studied. Intracranial flows were obtained using QMRA, and flow change with Diamox (QMRAΔd) was calculated as follows: ([flow after Diamox-flow before Diamox]/[flow before Diamox])×100%. Poor LMC was defined as grade 1 or 2, and robust LMC was defined as grade 3 or 4 based on the ASITN/SIR (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology) grading system on digital subtraction angiography. Thirty-eight patients had angiographic and flow data. Ipsilateral MCA QMRAΔd was significantly lower versus the contralateral side (flow, 85.5 versus 135.9 mL/min; P<0.001 and QMRAΔd, 24.0% versus 45.6%; P=0.01). If LMCs were robust (n=12), MCA QMRAΔd was significantly higher (21.4% versus -26.8%; P=0.04) compared with patients with poor LMC (n=4). We show that patients with more robust LMC have better MCA QMRAΔd. Therefore, QMRAΔd may be used for the functional assessment of LMC as a surrogate for cerebrovascular reserve in chronic internal carotid artery or MCA steno-occlusive disease.

Congenital Agenesis of Right Internal Carotid Artery: A Report of Two Cases.

Congenital unilateral agenesis of the internal carotid artery (ICA) is a rare anomaly. Due to proper sufficient collateral circulation via the circle of Willis most cases are asymptomatic, but patients can also present with ischemic or hemorrhagic cerebrovascular insults. The absence of the bony carotid canal is essential to differentiate this anomaly from chronic ICA occlusion. Awareness of this situation by clinicians and radiologists is essential because these patients have an increased incidence of various intracranial pathologies. We report two cases of this rare developmental congenital abnormality occurring in two young patients and describe the presentation, diagnosis, determined developmental causes, imaging findings, and complications.

Carotid endarterectomy alone or combined with fogarty catheter embolectomy for chronic symptomatic occlusion of the internal carotid artery

Objective To investigate the therapeutic effect of carotidendarterectomy(CEA) alone or combined with Fogarty catheter embolectomy in the treatment of chronic symptomatic internal carotid artery occlusion. Methods From April 2008 to December 2013, 12 patients with transient ischemic attack (TIA) or minor stroke underwent digital subtraction angiograph to confirmation t of ICA occlusion. All patients underwent operative exploration with CEA or CEA plus Fogarty thrombectomy. Patients who failed revascularization underwent external CEA and ICA ligation. All clinical and radiological data were retrospectively reviewed. Results CEA in 7 patients and CEA plus Fogarty thrombectomy in 3 patients were performed successfully to restore blood flow of internal carotid artery. External CEA and internal carotid artery ligation were performed in 2 patients. Postoperative CT angiography or DSA imaging demonstrated patency of the internal carotid artery in 10 patients. The ischemic symptoms were relieved in most of the patients. Postoperatively, 3 patients suffered from hyperperfusion syndrome, but there were no perioperative stroke or death.The duration of follow-up was 15-66 months. No patient developed a new stroke. No re-occlusion but one mild re-stenosis(40%) was detected. 2 patients suffered from TIA occasionally.One of the two patients failed in recanalization relieved from the symptom, the another still suffered from TIA. Conclusions Carotid endarterectomy alone or combined with Fogarty catheter embolectomy to treat chronic symptomatic internal carotid artery occlusion is feasible and safe, but preoperative evaluation and selection of patient should be carefully. Key words: Carotid artery, internal; Arterial occlusive diseases; Endarterectomy, carotid; Embolectomy; Fogarty catheter

Late spontaneous recanalization of symptomatic atheromatous internal carotid artery occlusion.

Definitive treatment of symptomatic atheromatous internal carotid artery occlusion remains controversial, as far as in rare cases, late spontaneous recanalization has been seen. We consecutively studied 182 patients (January 2003 to August 2012) with an ischemic stroke in the internal carotid artery territory and diagnosis of atheromatous internal carotid artery occlusion during hospitalization. Seven patients presented a late spontaneous recanalization (>3 months) of the internal carotid artery. We described therapeutic attitude according to usual care in these patients. The authors attempt to highlight the unusual condition of recanalization after a symptomatic atheromatous chronic internal carotid artery occlusion. If these patients can be treated similar to patients with asymptomatic carotid pathology, then this needs to be clarified. However, due to the risk of ipsi- and contralateral ischemic strokes, revascularization techniques should be considered in certain cases. More studies are needed to establish the most appropriate therapeutical approach in order to avoid arbitrary treatment of these patients.

Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion

Symptomatic internal carotid artery (ICA) occlusion with hemodynamic impairment remains a dismal disease when untreated. In this prospective, single-center, controlled study, we investigated the feasibility, safety, and long-term outcome of stenting by endovascular recanalization for patients with chronic ICA occlusion. Forty patients with symptomatic chronically occluded ICA were assigned to receive endovascular recanalization (group A, n = 18) or conservative management (group B, n = 22). The primary end point was 100% complete recanalization of the primary occlusion at 60 minutes, and secondary end points were improvement in neurologic function and cognitive function. Patients in the 2 groups were comparable in demographic and baseline characteristics. Successful recanalization was achieved in 88.9% (16 of 18) of patients with the restoration of Thrombolysis in Myocardial Ischemia/Thrombolysis in Cerebral Ischemia 2 or 3 flow. There was no procedural or new cerebral ischemic event. Improvement in brain perfusion was observed in 12 (12 of 18, 75%) patients on single-photon emission computed tomography. Improvement in neurologic function defined as a reduction of ≥4 points on the National Institutes of Health Stroke Scale (NIHSS) at 6 months was observed in group A (baseline, 6.83 ± 3.01 vs 6 months, 2.61 ± 1.20; P < .01) and group B (baseline, 6.05 ± 2.75 vs 6 months, 4.77 ± 1.69; P < .05). A significant difference in NIHSS scores was noted between group A and B at 1, 3, and 6 months (P < .05 or .001). Improvement in cognitive function defined as an increase of ≥8 on the Montreal Cognitive Assessment (MoCA) was observed in group A at 3 and 6 months (baseline, 14.67 ± 3.56 vs 3 months, 24.17 ± 3.55 and 6 months, 24.72 ± 2.85; P < .01). Significant improvement in MoCA was also observed in group B (P < .01). Furthermore, a significant difference in MoCA scores was noted between group A and B at 1, 3, and 6 months (P < .05 or .001). Endovascular recanalization is feasible and safe for patients with symptomatic chronic carotid artery occlusion. Successful carotid artery stenting can improve neurological function and global cognitive function than nonrevascularization.

Urgent Extracranial-Intracranial Bypass in the Treatment of Acute Hemodynamic Ischemic Stroke: Case Report

Extracranial-intracranial (EC-IC) bypass surgery is performed to allow flow augmentation in selected cases of occlusive cerebrovascular disease. The majority of EC-IC bypasses are described as an elective procedure in the prevention of hemodynamic ischemic stroke. There is only limited and controversial experience of superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis performed under urgent circumstances as a treatment of acute cerebral ischemia. We describe a unique case of a 75-year-old patient presenting with acute progressive hemodynamic ischemia after carotid endarterectomy (CEA), which developed contralaterally to the performed CEA in the region of chronic internal carotid artery (ICA) occlusion. Urgent performance of a standard STA-MCA bypass rapidly improved the cerebral hemodynamic and had an excellent therapeutic effect. The patient had recovered completely within 4 weeks of surgery. The role of urgent EC-IC bypass for stroke treatment is discussed.

網膜虚血により視力の急性増悪を呈した内頚動脈慢性閉塞症に対して血行再建術を施行した1例

網膜虚血により視力の急性増悪を呈した内頚動脈慢性閉塞症に対して血行再建術を施行した1例

Safety and Efficacy of Surgical Treatment of Carotid Stump Syndrome: Pilot Study

Surgical exclusion of the internal carotid artery (ICA) stump combined with endarterectomy of the external carotid artery is an established treatment approach. The aim of this pilot study was to compare the risk of cerebrovascular events between surgical treatment and best medical treatment in patients with ICA occlusion and carotid stump syndrome. Forty patients (23 males; age: 43-80 years; mean age: 61.1 ± 9.0 years) with carotid occlusion and carotid stump syndrome were enrolled. Ten patients with asymptomatic ICA occlusion and 10 patients with symptomatic ICA occlusion and carotid stump syndrome were enrolled to the best medical therapy group. Patients with chronic ICA occlusion, carotid stump syndrome, and one (15 patients) or recurrent (three patients) episodes of ipsilateral stroke or transient ischemic attack were enrolled to the surgical group. Neurological examination was undertaken on the day of randomization and then every 6 months in all patients for 4 years. All vascular events and death were recorded. Only one vascular event occurred in patients with symptomatic ICA occlusion without recurrent stroke or transient ischemic attack who were treated medically. No other vascular event was noted in the other subgroups. One patient with symptomatic carotid occlusion without recurrent stroke died due to myocardial infarction 6 months after surgery. Surgical treatment of carotid stump syndrome seems to be a safe procedure. Nevertheless, the benefit of a surgical approach in comparison with the best medical treatment is not clear.

Effect of Combination Therapy with the Angiotensin Receptor Blocker Losartan plus Hydrochlorothiazide on Brain Perfusion in Patients with both Hypertension and Cerebral Hemodynamic Impairment due to Symptomatic Chronic Major Cerebral Artery Steno-Occlusive Disease: A SPECT Study

Background: While the combination of an angiotensin receptor blocker with thiazide diuretics produces a clinically beneficial reduction in blood pressure in patients who otherwise only partially respond to monotherapy with an angiotensin receptor blocker, blood pressure-lowering therapy with combination antihypertensive drug regimens in patients with cerebral hemodynamic impairment may adversely affect cerebral hemodynamics. The purpose of the present exploratory study was to determine whether blood pressure-lowering therapy with the combination of the angiotensin receptor blocker losartan plus hydrochlorothiazide (LPH) worsens brain perfusion in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic major cerebral artery steno-occlusive disease. Methods: Patients with losartan-resistant hypertension and reduced cerebrovascular reactivity (CVR) to acetazolamide due to symptomatic chronic internal carotid artery (ICA) or middle cerebral artery (MCA) steno-occlusive disease were prospectively entered into the present study and received 50 mg/day of losartan plus 12.5 mg/day of hydrochlorothiazideat 14 weeks after the last ischemic event. Cerebral blood flow (CBF) and CVR were measured before and 12 weeks after initiating LPH using N-isopropyl-p-[¹²³I]-iodoamphetamine single-photon emission computed tomography (SPECT). A region of interest (ROI) was automatically placed in the MCA territory on each SPECT image using a three-dimensional stereotactic ROI template. Results: None of the 18 patients who participated in the study experienced any new neurological symptoms or adverse effects related to antihypertensive drugs. Systolic (p < 0.001) and diastolic (p < 0.001) blood pressures were significantly reduced after the administration of LPH, with average reductions of 11 mm Hg in systolic blood pressure and 10 mm Hg in diastolic blood pressure. While in the affected hemisphere CBF did not differ between measurements taken before and after the administration of LPH, CVR was significantly higher after the administration of LPH than before (p = 0.007) and was significantly improved in 5 of 18 patients. In the contralateral hemisphere, CBF and CVR did not differ between measurements taken before and after the administration of LPH. There were no patients who experienced a significant deterioration in CBF or CVR in the affected or contralateral hemisphere after the administration of LPH. Conclusions: Although the present study was exploratory and its results were preliminary due to the small sample size, the current data suggest that blood pressure-lowering therapy with LPH apparently does not result in worsening of cerebral hemodynamics in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic ICA or MCA steno-occlusive disease.

Response to Letter Regarding Article “Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion and Cerebral Ischemia”

Response: We appreciate the interest of Dr Sposato and his colleagues1 in our recent publication regarding neurocognitive function improvement after endovascular recanalization in patients with chronic carotid artery occlusion and ipsilateral hemisphere ischemia.2 The authors call attention to some methodological points in our study and are concerned about the interpretation of the result. First of all, they considered that group analysis may not reflect actual changes of individual patients. We therefore did event rate analysis according to their suggestion and still found a trend of a higher proportion of improvement in the successful group on 3 cognitive tests (Alzheimer Disease Assessment Scale–Cognitive Subtest: 8 of 12 [66.7%] versus …

Letter by Sposato et al Regarding Article, “Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion and Cerebral Ischemia”

To the Editor: We read with interest the article “Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion and Cerebral Ischemia” by Lin et al.1 The authors state that they found an improvement of global cognitive function, attention, and psychomotor processing speed in patients with chronic internal carotid artery occlusion undergoing carotid artery stenting. Similarly, in a recent prospective study, we found an improvement of executive functioning after carotid artery stenting among patients with internal carotid artery stenosis.2 Despite the innovative aspect of Lin et al's study (eg, comprising patients with internal carotid artery occlusion, unlike previous studies including participants with unilateral internal carotid artery stenosis), we would like to point out some concerns regarding methodological aspects that could affect the validity of its results. The authors found an improvement of mean values on the Alzheimer Disease Assessment Scale, …

Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion and Cerebral Ischemia

Chronic cerebral hypoperfusion may lead to impairment in neurocognitive performance in patients with chronic internal carotid artery occlusion, and the effects of carotid artery stenting on neurocognitive function have been unclear. We prospectively enrolled 20 chronic internal carotid artery occlusion patients with objective ipsilateral hemisphere ischemia, in whom carotid artery stenting was attempted. Functional assessments, including the National Institutes of Health Stroke Scale, Barthel Index, and a battery of neuropsychological tests, including the Mini-Mental State Examination, Alzheimer Disease Assessment Scale-Cognitive Subtest, verbal fluency, and Color Trail Making A and B, were administered before and 3 months after intervention. Successful recanalization was achieved in 12 of 20 patients (60%). There was no procedural or new cerebral ischemic event, except for 1 intracranial hemorrhage, which occurred during the procedure and had neurologic sequelae; this case was excluded from analysis. The demographics and baseline cognitive performance were similar between the group with a successful outcome (group 1, n=12) and patients who did not (group 2, n=7). Ten of 12 patients in group 1 had improvement in ipsilateral brain perfusion after the procedure, but none in group 2 had improvement. Significant improvement in the scores on the Alzheimer Disease Assessment Scale-Cognitive Subtest (before, 7.7±8.9 versus after, 5.7±7.1; P=0.024), Mini-Mental State Examination (before, 25.8±3.8 versus after, 27.7±2.7; P=0.015), and Color Trail Making A (before, 123.2±68.6 versus after, 99.3±51.5; P=0.017) were found in group 1 but not in group 2. Successful carotid artery stenting improves global cognitive function as well as attention and psychomotor processing speed in patients with chronic internal carotid artery occlusion.

Perioperative nursing of interventional therapy for patients with chronic occluded internal carotid artery

Objective To investigate perioperative nursing of interventional therapy for patients with chronic occluded internal carotid artery. Methods We retrospectively analyzed the clinical nursing data of 12 patients with chronic occlusion of internal carotid artery who were successfully performed recanalization for the occluded vessels. Results The vital signs of all patients were normal during the procedures. The patients got favorable outcomes and no complications occurred during the perioperation. Conclusions Interventional therapy for chronic occlusion of internal carotid artery is a new technology for carotid diseases. Perfect preoperative health education and psychological nursing, comprehensive monitoring of vital signs and nerve function, strengthening body position nursing can ensure prevention of complications and the success of surgery. Key words: Internal carotid artery; Occlusion; Stent; Nursing

Ultrasonographic and Perioperative Macroscopic Findings in Acute Carotid Artery Occlusion

acute ischemic stroke (AIS) may occur both in the acute and chronic internal carotid artery occlusion (ICAo). Thus, it is important to assess the ICAo character when considering the recanalization method. The aim was to assess the agreement between the ultrasonographic (US) and perioperative macroscopic (PM) finding in AIS patients with acute ICAo, undergoing an emergent carotid endarterectomy. in a retrospective, hospital-based study, the set consisted of 47 patients (36 males; age 49-79, mean 63.7 ± 8.5 years). ICAo character was classified as an acute thromboembolus either isolated or in combination with atherosclerotic plaque using the US (B-mode) and the PM evaluation. Cohen's Kappa and AC(1) coefficient were applied to assess the methods agreement. an acute ICAo character diagnosed by US was confirmed by the PM evaluation in all cases. US and PM findings were consistent in 41 cases. The agreement between both methods in the classification of acute ICAo was 87.2% [95% confidence interval (CI): 77.7-96.8%], κ= .589 (95% CI: .293-.885) (P < .0001), AC(1) = .815. US is a reliable method in the diagnostics of the acute character of ICAo and it has a good agreement with PM finding regarding a differentiation of atherosclerotic plaque and fresh thromboembolus.

Spontaneous Recanalization of Chronic Internal Carotid Artery Occlusions: Report of 3 Cases

Spontaneous recanalization of a chronically occluded internal carotid artery (ICA) is a rare occurrence. The authors report 3 patients who had documented total occlusion of the ICA followed by late spontaneous recanalization with subsequent high-grade stenosis. The patients in this series had occlusions for 11 months, 36 months, and 39 months, respectively. One patient had symptoms ipsilateral to the recanalized vessel, and 2 patients were asymptomatic. Endarterectomy was performed uneventfully in 2 patients and pathologic specimens demonstrated typical atherosclerotic plaque with patent lumens. Our experience demonstrates that although chronic recanalizations of occluded ICAs are rare, this does occur. Pathology demonstrates typical atherosclerotic plaque which appeared to have been recanalized by lysis of thrombus. The natural history of this condition is not well known and indications for intervention are not well established.

Brain Temperature Measured Using Proton MR Spectroscopy Detects Cerebral Hemodynamic Impairment in Patients With Unilateral Chronic Major Cerebral Artery Steno-Occlusive Disease

Brain temperature is determined by the balance between heat produced by cerebral energy turnover and heat removed by cerebral blood flow. The purpose of the present study was to investigate whether brain temperature measured noninvasively using proton MR spectroscopy can detect cerebral hemodynamic impairment in patients with unilateral chronic internal carotid or middle cerebral artery occlusive disease when compared with positron emission tomography. Brain temperature, cerebral blood flow, and metabolism were measured using proton MR spectroscopy and (15)O-positron emission tomography, respectively, in 21 normal subjects and 37 patients. Positron emission tomography images were coregistered with MR images and resliced automatically using image analysis software. Regions of interest placed in both cerebral hemispheres on MR images were automatically superimposed in these resliced positron emission tomography images. A significant correlation was observed between brain temperature difference (affected hemisphere-contralateral hemisphere) and both cerebral blood volume and oxygen extraction fraction ratio (affected hemisphere/contralateral hemisphere; r=0.607; P=0.0004 and r=0.631; P=0.0002). With abnormally elevated cerebral blood volume or oxygen extraction fraction ratio defined as higher than the mean +2 SDs obtained from normal subjects, brain temperature difference provided 86% or 92% sensitivity and 87% or 84% specificity with 80% or 73% positive and 91% or 95% negative predictive values for detecting abnormally elevated cerebral blood volume or oxygen extraction fraction ratios, respectively. Brain temperature measured using proton MR spectroscopy can detect cerebral hemodynamic impairment in patients with unilateral chronic major cerebral artery steno-occlusive disease.

Cortical excitability and ischemia in patients with chronic unilateral internal carotid artery occlusion

Abstract Relationships between cortical excitability and regional cerebral blood flow (rCBF) were investigated in eight patients with chronic internal carotid artery occlusion using somatosensory evoked field recovery function (SEF-R). At interstimulus intervals (ISIs) of 120 and 160 ms, the SEF-R curve of the affected hemisphere demonstrated a significant overshoot above that of the non-affected hemisphere, suggesting cortical hyperexcitability. Furthermore, the rCBF at the hand area of the primary sensory area and the SEF-R at the ISI of 160 ms were inversely correlated. These results suggest that cortical hyperexcitability occurs at the primary sensory area in association with the severity of ischemia in the patients with chronic ICA occlusion.

Carotid angioplasty with stenting for chronic internal carotid artery occlusion: technical note

Carotid angioplasty with stenting (CAS) is becoming accepted as an effective and reliable treatment option for severe carotid artery stenosis. However, it is rarely applied for carotid occlusion, especially in its chronic stage. We report our experience of CAS for chronic internal carotid artery occlusion representing compromised cerebral blood flow using various protection methods. A 77-year-old woman, who was already diagnosed with severe left internal carotid artery stenosis, suddenly had right hemiparesis and aphasia. At that time, she was treated conservatively because her neurological status was quite good, in spite of left carotid artery occlusion. Her symptoms improved in the short term, except slight aphasia, but deteriorated again 18 days from the onset, and magnetic resonance imaging (MRI) showed new ischemic lesions. CAS was then performed for the occluded carotid artery on the 23rd day from the first onset. Using the proximal protection technique, the occluded lesion was crossed carefully with a microguidewire. Stents were also placed successfully with the distal protection technique. The occluded carotid artery was completely recanalized without any unfavorable events or neurological deterioration. In this patient, CAS was successfully to treat chronic carotid artery occlusion. These procedures and techniques are reviewed and discussed.

Unusual Case of 2 Renal Cell Carcinoma Metastases Ipsilateral to an Occluded Internal Carotid Artery

Hemodynamic factors may play a role in the seeding and subsequent growth of cerebral metastasis. The authors present a case with 2 foci of cerebral metastasis in the same vascular territory ipsilateral to an occluded internal carotid artery. A 65-year-old man with chronic left frontal lobe infarct and left internal carotid artery occlusion was diagnosed with 2 large hemorrhagic metastases in the left middle cerebral artery territory. Diminished flow signals were seen in the trunk and branches of the left middle cerebral artery on magnetic resonance angiography. This case illustrates preferential seeding and growth of cerebral metastases in a region of the brain with diminished blood flow.