Stroke in patients with occlusion of the internal carotid artery: options for treatment

Endovascular recanalization of subacute or chronic symptomatic occlusion of the internal carotid artery ophthalmic segment

OBJECTIVE

To investigate the safety and effect of endovascular recanalization for subacute or chronic occlusion of the internal carotid artery (ICA) ophthalmic segment and risk factors for the prognosis.

MATERIALS AND METHODS

135 patients with subacute or chronic occlusion of the ICA ophthalmic segment were retrospectively enrolled to undergo endovascular recanalization, with the clinical, imaging and follow-up data being analyzed.

RESULTS

Among 135 patients with ICA ophthalmic segment occlusion, hypertension was presented in 72 (53.3 %) patients, diabetes mellitus in 44 (32.6 %), coronary heart disease in 12 (8.9 %), smoking in 51 (37.8 %), and alcohol abuse in 38 (28.1 %). Endovascular recanalization was performed in all patients, and recanalization was successful in 130 (96.3 %). Five patients (3.7 %) were not recanalized because of intraprocedural complications. Periprocedural complications occurred in 16 patients, resulting in a total complication rate of 11.9 %. The mRS (modified Rankin Scale score) was 1.45 ± 0.03 after recanalization, significantly (P < 0.001) better than that (2.25 ± 0.12) before recanalization. The NIHSS (National Institute of Health Stroke Scale) was 11.91 ± 0.67, significantly (P < 0.0001) better than that (18.45 ± 1.33) before recanalization. Eighty-nine (65.9 %) patients underwent angiography at follow-up 6-86 (mean 48) months after recanalization, which demonstrated good prognosis in 72 (80.9 %) patients and poor prognosis in the other 17 (19.1 %) with instent restenosis > 50 %. Telephone follow-up was conducted in 46 (34.1 %) patients 6-38 (mean 27) months after recanalization, which revealed good prognosis in 38 (82.6 %) patients and poor prognosis in 8 (17.4 %). In total, good prognosis was present in 110 (81.5 %) patients while poor prognosis in 25 (18.5 %). In angiographic follow-up, instent restenosis > 50 % was present in nine (10.1 %) patients. Univariate analysis showed age (OR = 1.82), hypertension (OR = 2.38), diabetes mellitus (OR = 1.84), and alcohol abuse (OR = 1.49) were significant (P < 0.05) risk factors, whereas multivariate analysis demonstrated that only hypertension (OR = 1.54) and diabetes mellitus (OR = 2.67) were significant (P < 0.05) independent risk factors to affect the prognosis of recanalization.

CONCLUSION

Subacute or chronic occlusion of the internal carotid artery ophthalmic segment can be safely and efficiently recanalized using endovascular skills, and hypertension and diabetes mellitus are the independent risk factors for the prognosis of endovascular recanalization.

Efficacy and safety of anticoagulant and antiplatelet therapies in the medical management of carotid free-floating thrombus: A systematic review

BACKGROUND

The optimal treatment for carotid free-floating thrombus (CFFT) remains uncertain due to limited evidence, with no randomized clinical trials and scarce guidelines, such as ESVS 2023, favoring conservative management. Anticoagulation (ACT) and antiplatelet (APT) therapies are emerging as promising alternatives to high-risk surgical interventions. This systematic review aimed to evaluate the safety and efficacy of ACT and APT therapies for CFFT.

METHODS

A systematic search was performed across PubMed, Embase, Web of Science, and Cochrane databases. Safety and efficacy endpoints were assessed. A two-sample t-test compared baseline characteristics between groups, and a Chi-square test evaluated differences in categorical variables. Statistical significance was set at p < 0.05. Data were analyzed using R 4.3.0 with the meta package v.7.0-0.

RESULTS

Four studies met the inclusion criteria, involving 170 patients diagnosed with CFFT. The APT group included 96 patients (mean age 55.35 ± 13.52 years; 56.25% male), and the ACT group included 74 patients (mean age 58.57 ± 14.28 years; 51.35% male). Thrombus regression was slightly lower in APT (42%) compared to ACT (48%). Both groups showed similar rates of residual stenosis. Antiplatelet had fewer ischemic events within 30 days (none vs. 4% in ACT) and lower intracranial hemorrhage rates (3.3% vs. 5.4% in ACT) but higher mortality (6.3% vs. none in ACT).

CONCLUSION

Both ACT and APT are effective for managing CFFT, each with distinct efficacy and safety profiles. However, randomized trials are necessary to better assess these therapies in CFFT management.

Diagnostic Value of Perfusion Parameters for Differentiation of Underlying Etiology in Internal Carotid Artery Occlusions

PURPOSE

Occlusions of the internal carotid artery (ICA) may be caused by dissection, embolic or macroangiopathic pathogenesis, which partially influences the treatment; however, inferring the underlying etiology in computed tomography angiography can be challenging. In this study, we investigated whether computed tomography perfusion (CT-P) parameters could be used to distinguish between etiologies.

METHODS

Patients who received CT‑P in acute ischemic stroke due to ICA occlusion between 2012 and 2019 were retrospectively analyzed. Group comparisons between etiologies regarding the ratios of CT‑P parameters between both hemispheres for relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), time to maximum (Tmax), and mean transit time (MTT) were calculated by one-factorial analysis of variance (ANOVA) and compared by pairwise Bonferroni post hoc tests. An receiver operating characteristics (ROC) analysis was performed if differences in group comparisons were found. Multinomial logistic regression (MLR) including pretherapeutic parameters was calculated for etiologies.

RESULTS

In this study 69 patients (age = 70 ± 14 years, dissection = 10, 14.5%, embolic = 19, 27.5% and macroangiopathic = 40, 58.0%) were included. Group differences in ANOVA were only found for MTT ratio (p = 0.003, η2 = 0.164). In the post hoc test, MTT ratio showed a differentiability between embolic and macroangiopathic occlusions (p = 0.002). ROC analysis for differentiating embolic and macroangiopathic ICA occlusions based on MTT ratio showed an AUC of 0.77 (p < 0.001, CI = 0.65-0.89) and a cut-off was yielded at a value of 1.15 for the MTT ratio (sensitivity 73%, specificity 68%). The MLR showed an overall good model performance.

CONCLUSION

It was possible to differentiate between patients with embolic and macroangiopathic ICA occlusions based on MTT ratios and to define a corresponding cut-off. Differentiation from patients with dissection versus the other etiologies was not possible by CT‑P parameters in our sample.

Spotlight on clinical strategies of Chronic Internal Carotid Artery Occlusion: Endovascular interventions and external-intracarotid bypasses compared to conservative treatment

Chronic internal carotid artery occlusion (CICAO) has high prevalence and incidence rates, and patients with CICAO can be completely asymptomatic, experience a devastating stroke or die. It is important to note that CICAO causes cerebrovascular accidents. Currently, the external carotid-internal carotid (EC-IC) bypass technique is used to treat CICAO. However, many clinical studies showed that EC-IC bypass was not beneficial for many patients with CICAO. Meanwhile, endovascular intervention treatment options for CICAO are evolving, and an increasing number of patients are undergoing endovascular intervention therapy. Accordingly, a review comparing both techniques is warranted. For this review, we searched PubMed and collected relevant case study reports comparing endovascular interventional therapy and internal and external cervical bypass surgeries to provide strategies for clinical treatment.

Vascular Diameters as Predictive Factors of Recanalization Surgery Outcomes in Internal Carotid Artery Occlusion

Background: Revascularization surgery sometimes can achieve recanalization in patients with internal carotid artery occlusion (ICAO). High-resolution vessel wall magnetic resonance imaging (HRVWI) is a feasible technique to give detailed characteristics of the vessel wall, which may help to identify patients that carry higher success rates and more suitable for revascularization surgery. Objective: To examine the association between HRVWI characteristics of ICAO and the success rate of revascularization surgery in ICAO patients. Methods: We conducted a retrospective analysis of 31 ICAO recanalization patients enrolled from October 2017 to May 2019. The clinical data of patients and lesions were collected and analyzed. Results: A total of 31 ICAO patients were enrolled in this study. No significant differences were found between recanalization success and recanalization failure groups with regard to occlusion length, distal end of the occluded segment, and the treatment applied. The ipsilateral-to-contralateral diameter ratios (I/C ratios) of C1 or C2 and the diameter of C7 were positively related to recanalization success. A two-factor predictive model was constructed, and the I/C ratio of C2 < 0.86 and the diameter of C7 < 1.75mm were separately assigned 1 point. The ICAO patients who scored 0, 1, or 2 points had a risk of 5.6% (1/18), 55.6% (5/9), or 100% (4/4) to fail in the recanalization. Conclusions: The I/C ratios of C1 or C2 and the diameter of C7 are predictive factors of a revascularization surgery success in ICAO patients. A risk stratification model involving C2 and C7 was constructed for future clinical applications.

Deficiency in CD4 T Cells Leads to Enhanced Postpartum Internal Carotid Artery Vasoconstriction in Mice: The Role of Nitric Oxide

The risk of postpartum (PP) stroke is increased in complicated pregnancies. Deficiency in CD4 T cell subsets is associated with preeclampsia and may contribute to PP vascular disease, including internal carotid artery (ICA) stenosis and stroke. We hypothesized that CD4 T cell deficiency in pregnancy would result in ICA dysregulation, including enhanced ICA vasoconstriction. We characterized the function, mechanical behavior, and structure of ICAs from C57BL/6 (WT) and CD4 deficient (CD4KO) mice, and assessed the role of NO in the control of ICA function at pre-conception and PP. WT and CD4KO mice were housed under pathogen-free conditions, mated to same-strain males, and allowed to litter or left virgin. At 3 days or 4 weeks PP, mice were euthanized. The responses to phenylephrine (PE), high K⁺ and acetylcholine (ACh) were assessed in pressurized ICAs before and after NOS inhibition. Passive lumen diameters were measured at 3–140 mmHg. eNOS and iNOS expression as well as the presence of T cells were evaluated by immunohistochemistry. Constriction of WT ICAs to PE was not modified PP. In contrast, responses to PE were significantly increased in ICAs from PP as compared to virgin CD4KO mice. Constriction to high K⁺ was not enhanced PP. ICAs from WT and CD4KO mice were equally sensitive to ACh with a significant rightward shift of dose-response curves after L-NNA treatment. NOS inhibition enhanced PE constriction of ICAs from WT virgin and PP mice. Although a similar effect was detected in ICAs of virgin CD4KO mice, no such changes were observed in vessels from PP CD4KO mice. Passive arterial distensibility at physiological levels of pressure was not modified at PP. ICA diameters were significantly increased in PP with no change in vascular wall thickness. Comparison of eNOS expression in virgin, 3 days and 4 weeks PP revealed a reduced expression in ICA from CD4 KO vs. WT PP vessels which reached significance at 4 weeks PP. iNos expression was similar and decreased over the PP period in vessels from WT and CD4KO mice. Dysregulation of the CD4 T cell population in pregnancy may make ICA vulnerable to vasospasm due to decreased NO-dependent control of ICA constriction. This may lead to cerebral hypoperfusion and increase the risk of maternal PP stroke.

Establishment of Carotid Artery Dissection and MRI Findings in a Swine Model

Carotid artery dissection (CAD) is the leading cause of ischemic stroke in young patients; however, the etiology and pathophysiology of CAD remain largely unknown. In our study, two types of dissections (length × width: 1.5 cm × 1/3 circumference of intima, Group I, n = 6; or 1.5 cm × 2/3 circumference of intima, Group II, n = 6) were created between the media and intima. Ultrasound (within 2 h after dissection) showed a dissociated intima in the lumen and obstructed blood flow in the surgical area. Digital subtraction angiography (DSA, 72 h after dissection), magnetic resonance imaging (MRI, 72 h after dissection), and hematoxylin–eosin (H&E, 7 days after dissection) staining confirmed stenosis (33.67 ± 5.66%) in Group I and total occlusion in Group II. In 10 out of 12 swine, the CAD model was established using a detacher and balloon dilation, and morphological outcomes (stenosis or occlusion) after CAD were determined by the size of intimal incision.

Recanalization of symptomatic chronic internal carotid artery occlusions by hybrid treatment

OBJECTIVE

To evaluate the efficacy and safety of hybrid revascularization by carotid endarterectomy and endovascular intervention in the treatment of chronic internal carotid artery occlusion (ICAO).

METHODS

We performed a retrospective analysis of patients who received hybrid treatment for symptomatic chronic ICAO between December 2016 and December 2018. Fifty-six patients with long-segment ICAO were enrolled and divided into the short duration (1-3 months) and long ICAO duration (>3 months) groups, and their clinical and angiographic data were analyzed.

RESULTS

The mean duration was 106.8 ± 36.1 days from the date of ICAO diagnosis to revascularization. Totally, 10 patients (17.8%, n = 56) in the short duration group while no patients in the long duration group failed recanalization (n = 7). Perioperative complications included intraoperative thromboembolism in 1 (1.8%) patient and subarachnoid hemorrhage in 2 (3.6%) patients. Early phase postoperative hypertension was noted in 11 (19.6%) patients and cervical hemorrhage in 1 (1.8%) patient. No severe neurological deficits occurred. Overall, the 6-month modified Rankin score, Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores in patients with successful recanalization significantly improved versus the baseline (P < 0.05). After successful recanalization, the long duration group demonstrated more stents for revascularization compared with the short duration group (P < 0.05). Five (10.8%) patients had recurrent transient ischemic attack, and 1 (2.2%) patient developed stroke in the successful revascularization group during 6 months of follow-up. ICA restenosis occurred in 5 (8.9%) patients and re-occlusion was noted in 1 (1.8%) patient.

CONCLUSIONS

Hybrid operation may be feasible and effective for patients with symptomatic chronic complete ICAO according to our limited data. The original occlusion site from the carotid bifurcation and the duration of ICAO should be considered as independent indicators for successful recanalization as well as perioperative outcomes.

Physiologic and Pathologic Calcifications of Head and Neck Significant to the Dentist

This article aims to help the practitioner identify structures found in routine three-dimensional imaging studies of the head and neck region and understand their significance and possible need for intervention. The prevalence of advanced imaging in dental practice, especially cone beam computed tomography, highlights the need to recognize and identify various high-density structures that are, in fact, soft tissue calcifications or alterations of normal bony anatomy. The wide range of these findings includes both benign and malignant pathologic entities as well as age-related calcifications and remodeling of normal anatomic structures and dystrophic calcifications.

Subclavian Artery to Internal Carotid Artery Interpositional Bypass for Carotid Artery Occlusion: Technical Case Report

BACKGROUND AND IMPORTANCE

Conventional microsurgical treatment for symptomatic internal carotid artery (ICA) occlusion is revascularization with superficial temporal artery (STA) to middle cerebral artery bypass. However, in rare cases where the common carotid artery, external carotid artery (ECA), or both are also occluded, other microsurgical treatment options must be considered.

CLINICAL PRESENTATION

We present the case of a 52-yr-old woman with common carotid artery occlusion and weak ICA flow from collateral connections between the vertebral artery, occipital artery, and ECA. She had ischemic symptoms and a history of stroke. The patient's STA was unsuitable as a donor vessel due to its small caliber and poor flow, and we instead performed an interpositional bypass from the subclavian artery to the ICA using a radial artery graft.

CONCLUSION

This case illustrates the successful use of the subclavian artery to ICA bypass technique with an interpositional radial artery graft. The surgical anatomy of the subclavian arteries is reviewed, and the technical details of subclavian artery to radial artery graft to ICA interpositional bypass are presented.

Free-Floating Thrombus in the Distal Internal Carotid Artery Causing a Stroke

We present a patient suffering from a stroke with a free-floating thrombus extending up to the distal internal carotid artery. The thrombus was totally resolved after a 2-week anticoagulation regimen without leaving behind any severe residual stenosis in the carotid bulb. The optimal treatment of this rare condition remains uncertain. We report some important treatment strategies that have been used in the literature, emphasizing the anticoagulation as the mainstay of therapy. Immediate surgical and interventional manipulations carry the risk of thrombus dislodgement and embolization and should be considered if there are recurrent symptoms despite medical management.

Severe cerebral edema induced by watershed shift after bypass in a patient with chronic steno-occlusive disease: a case report and short literature review

Background

Carotid occlusive disease is a type of progressive disease resulting in ischemic stroke. Extracranial-intracranial bypass surgery represents a valid therapeutic option when medical treatment does not make effects. The appearance of cerebral edema following bypass is common during acute stage. Additionally, there are many causes of mild cerebral edema, such as hemodynamic changes, venous congestion and others. However, severe edema involving large brain tissue, which presents as reversible aphasia and hemiplegia, remains to be elucidated.

Case presentation

A 55-year-old man was admitted to the neurosurgery department for repeated dizziness for over a year and sudden onset of syncope 1 month prior, and he was diagnosed with carotid occlusive disease. After surgical contraindications were excluded, dual bypass and encephalo-duro-myo-synangiosis were performed. Although blood pressure and fluid management were strictly under control promptly after surgery, massive cerebral edema involving the left anterior cerebral artery and middle cerebral artery territories occurred from the 6th day after surgery. Additionally, no discernible cerebral infarction or hemorrhage occurred. Moreover, the cerebral blood flow of the middle cerebral artery displayed an early decrease followed by delayed elevation on the left side. Without restricting the spreading of cerebral edema, life-threatening cerebral herniation could develop at any time. Mannitol and furosemide were administered for impending cerebral herniation. The amelioration of symptoms was noticed on the 16th day after surgery. The patient felt relief on the 21st day after surgery. Digital subtraction angiography performed on the 180th day after surgery demonstrated the patency of dual anastomosed vessels, and the patient recovered without any permanent neurological deficit.

Conclusion

Based on changes in cerebral blood flow and reversible symptoms, the “watershed shift” phenomenon could explain such a severe deficit. However, this deficit was not the same as the classical presentation of the “watershed shift”, which involves a moderate amount of brain tissue and presents significant increases in cerebral blood flow. In addition to the “watershed shift”, a swollen temporal muscle may also participate in the progression of focal edema.

Functional outcome after symtomatic internal carotid artery occlusion

Abstract Internal carotid artery occlusion accounts for 15-20% of ischemic strokes, caused by atherosclerosis or dissection. Clinical symptoms are variable, from asymptomatic cases to minor or severe strokes. Diagnosis in internal carotid artery (ICA) occlusion is based on imaging techniques. Prognosis after ICA occlusion depends on many factors: severity of neurologic deficit, spontaneous recanalization of the artery, and the occurrence of recurrent strokes. Patients with spontaneous recanalization of the occluded ICA tend to have a retained functional ability and favorable clinical outcomes. Medical treatment, recanalization techniques and intensive rehabilitation program are essential in improving functional outcome of patients with stroke produced by ICA occlusion. We present the case of a young patient diagnosed with ischemic stroke produced by internal carotid artery occlusion, with consecutive severe neurologic deficit, and an unfavorable functional outcome, as evaluated with the Modified Rankin Scale. Spontaneous recanalization of the occluded ICA was observed after 6 weeks, suggesting a carotid dissection. The patient was included in an intensive rehabilitation program, associated with best medical therapy, showing improvement of its functional status at 3 months follow up. Key words: ischemic stroke, carotid artery occlusion, carotid dissection, spontaneous recanalization, functional outcome,

Current understanding of chronic total occlusion of the internal carotid artery

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.

Malignant Cerebral Swelling After Cranioplasty due to Ipsilateral Intracranial Vasculopathy: Case Report and Literature Review

BACKGROUND

Cranioplasty is a well-established surgical operation that is used worldwide for patients with skull defects following decompressive craniectomy (DC). However, in some cases, potentially fatal complications may occur, such as malignant cerebral swelling after uneventful cranioplasty.

CASE DESCRIPTION

We present a rare case of massive malignant ipsilateral cerebral swelling following uneventful titanium mesh cranioplasty due to rare ipsilateral intracranial vasculopathy confirmed by magnetic resonance angiography (MRA) and magnetic resonance venography (MRV). Fortunately, we performed titanium mesh explantation and extended DC in time, and the patient survived. Malignant cerebral swelling after uneventful cranioplasty is an unpredictable but fatal complication. Most reported cases have had an unfavorable prognosis. To the best of our knowledge, the mechanism was first confirmed by MRA and MRV, which demonstrated that the cerebral swelling was due to unilateral intracranial vasculopathy, including a rare ipsilateral intracranial internal carotid artery occlusion, as well as extremely thin lateral and sigmoid sinuses.

CONCLUSIONS

Our case demonstrates for the first time that ipsilateral intracranial vasculopathy is a risk factor for malignant cerebral swelling after cranioplasty. Patients with traumatic brain injury with suspected intracranial vasculopathy should undergo a comprehensive vascular evaluation before cranioplasty to help prevent malignant cerebral swelling.

Acute Carotid Stent Thrombosis

Acute carotid stent thrombosis (ACST) is a rare complication that can lead to dramatic and catastrophic consequences. A rapid diagnosis and prompt recanalization of the internal carotid artery are needed to minimize the ischemic insult and the reperfusion injury. We reviewed the current literature on this devastating complication of CAS with the intention of investigating the potential causative factors and to define the appropriate management. According to our study discontinuation of antiplatelet therapy, resistance to antiplatelet agents and inherent or acquired thrombotic disorders are the main causes of thrombosis. Technical intraprocedural parameters such as dissection, atheroma prolapse, kinking of the distal part of internal carotid artery and embolic protection device occlusion can also result in early carotid stent thrombosis. Rapid reperfusion ensures an improved neurological outcome and a better prognosis in the short and long term. Thrombolysis, mechanical thrombectomy or thromboaspiration in combination with drug or thrombolytic therapy, surgical therapy and re-angioplasty are treatment options that have been used with encouraging results. In conclusion, optimal perioperative antiplatelet treatment as well as technical considerations regarding the carotid artery stenting plays a determinant role.

Recovery Potential After Acute Stroke

In acute stroke, the major factor for recovery is the early use of thrombolysis aimed at arterial recanalization and reperfusion of ischemic brain tissue. Subsequently, neurorehabilitative training critically improves clinical recovery due to augmention of postlesional plasticity. Neuroimaging and electrophysiology studies have revealed that the location and volume of the stroke lesion, the affection of nerve fiber tracts, as well as functional and structural changes in the perilesional tissue and in large-scale bihemispheric networks are relevant biomarkers of post-stroke recovery. However, associated disorders, such as mood disorders, epilepsy, and neurodegenerative diseases, may induce secondary cerebral changes or aggravate the functional deficits and, thereby, compromise the potential for recovery.