Common carotid artery occlusion: a case series

Symptomatic Common Carotid Artery Stenosis Managed With Carotid Endarterectomy

Extracranial carotid artery disease is typical at the carotid bifurcation and internal carotid artery (ICA) and is rarely symptomatic from isolated common carotid artery (CCA) stenosis. We present the case of a 60-year-old female patient who presented with a transient ischemic attack (TIA) with significant stenosis of the ipsilateral CCA only, without any involvement of the ICA or bifurcation. This was treated with carotid endarterectomy (CEA) with desirable postoperative outcomes; at up to six months postoperative follow-up, this patient had no recurrence of symptoms. We draw attention to the current gap in the literature with regard to a lack of specific guidelines for optimal evidence-based surgical treatment for this specific condition, with recent advances within certain vascular societies.

Ablation of Vitamin D Signaling Compromises Cerebrovascular Adaptation to Carotid Artery Occlusion in Mice

Vitamin D insufficiency has been associated with increased incidence and severity of cerebrovascular disorders. We analyzed the impact of impaired vitamin D signaling on the anatomical and functional aspects of cerebrovascular adaptation to unilateral carotid artery occlusion (CAO), a common consequence of atherosclerosis and cause of ischemic stroke. Cerebrocortical blood flow (CoBF) showed a significantly increased drop and delayed recovery after CAO in mice carrying a functionally inactive vitamin D receptor (VDR) with the most sustained perfusion deficit in the temporal cortex. To identify the cause(s) for this altered adaptation, the extent of compensatory blood flow increase in the contralateral carotid artery and the morphology of pial collaterals between the anterior and middle cerebral arteries were determined. Whereas VDR deficiency had no significant influence on the contralateral carotid arterial blood flow increase, it was associated with decreased number and increased tortuosity of pial anastomoses resulting in unfavorable changes of the intracranial collateral circulation. These results indicate that VDR deficiency compromises the cerebrovascular adaptation to CAO with the most sustained consequences in the temporal cortex. The dysregulation can be attributed to the altered development and function of pial collateral circulation whereas extracranial vessels may not be impaired.

Disobliteration of an Occluded Common Carotid Artery with Patent Bifurcation via Antegrade Ring Stripping

There is a lack of guidelines concerning common carotid artery (CCA) occlusive disease in the presence of a patent internal carotid artery (ICA). A novel surgical technique that disobliterates an occluded CCA was successfully performed in three cases. The detailed surgical steps are presented herein. After proximal division of the CCA behind the sternoclavicular junction, the occluded CCA was endarterectomized via antegrade ring stripping. After removal of the atheromatous core, the CCA was everted, and the wall remnants were cleaned under direct vision. Simultaneous eversion endarterectomy of the ICA was performed when necessary. After reversion of the CCA, it was transposed and anastomosed to the ipsilateral subclavian artery distal to the orifice of the vertebral artery. This novel technique can be used in selected cases by experienced surgeons.

Endovascular recanalization of common carotid artery Total occlusion: two case reports and literature review

Background

Common carotid artery total occlusion is rare but can be associated with a variety of neurological symptoms due to inadequate cerebral perfusion. The treatment includes bypass surgery, endarterectomy, and endovascular revascularization.

Case presentation

Herein, we report two cases of common carotid artery total occlusion treated by percutaneous transluminal angioplasty, and review the literature.

Conclusion

Both of our cases were successfully treated with endovascular revascularization for common carotid artery total stenosis. Endovascular therapy provided an alternative treatment. Further large clinical study for comparing the safety and efficiency in surgical and endovascular treatment may be required.

Level of evidence

Level 4, Case Series.

Cerebroprotective Effect against Cerebral Ischemia of the Combined Extract of Oryza sativa and Anethum graveolens in Metabolic Syndrome Rats

The novel strategy against ischemic stroke in metabolic syndrome (MetS) targeting at oxidative stress and inflammation has gained attention due to the limitation of the current therapy. Due to the antioxidant and anti-inflammation of the combined extract of Oryza sativa and Anethum graveolens, the cerebroprotective effect against cerebral ischemia in MetS condition has been focused. Since no data were available, this study was set up to determine the effects of the combined extract of Oryza sativa L. and Anethum graveolens Linn. against ischemic stroke in the animal model of metabolic syndrome. The possible underlying mechanism was also further investigated. Male Wistar rats (180-220 g) were fed with high-carbohydrate high-fat diet (HCHF diet) to induce metabolic syndrome-like condition. Then, MetS rats were subjected to reperfusion injury at the right middle cerebral artery. The combined extract of O. sativa and A. graveolens (OA extract) at doses of 0.5, 5, and 50 mg/kg BW was fed once daily for 21 days. Neurological assessment was performed every 7 days throughout the experimental period. At the end of study, brain infarction volume, neuron and glial fibrillary acidic protein- (GFAP-) positive cell density, the oxidative stress status, the expressions of proinflammatory cytokines (NF-κB, IL-6), and eNOS in the cortical area together with the expression of VCAM-1 and the histological changes of common carotid artery were determined. It was found that OA extract decreased brain infarction, neurological score, oxidative stress status, and inflammatory mediators but increased eNOS expression in the cortical area; the increased VCAM-1 and intima-media thickness together with the reduction of lumen diameter of common carotid artery of MetS eats with MCAO were also mitigated by OA extract. These data suggest the cerebroprotective effect of OA, and the underlying mechanism may occur partly via the improvement of oxidative stress status, inflammation, and brain blood supply.

Evaluation of revascularization after total arch replacement in common carotid artery occlusion

Occlusion of the common carotid artery (CCA) is rare. CCA occlusion (CCAO) can present as drowsiness and right hemiplegia related to emboli after total arch replacement. Although we selected a follow-up at first because color duplex sonography showed retrograde flow from the left external carotid artery to the internal carotid artery, this patient had epilepsy and single-photon emission computed tomography (SPECT) acquired quantitative results of actual brain perfusion and showed insufficient collateral blood flow. To improve brain perfusion, we performed a bypass of the left subclavian artery to left CCA bypass. Postoperatively, the patient did not have epilepsy and drowsiness. Also, right hemiplegia improved enough for him to walk with support. SPECT showed increased left cerebral flow (the asymmetry ratio was 71% to 81%). Evaluation of the carotid artery with color duplex sonography alone was insufficient when CCAO showed retrograde or collateral flow. We should have performed quantitative evaluation with SPECT at the same time.

Carotid-Carotid Artery Crossover Bypass with a Synthetic Vascular Graft for Symptomatic Type 1A Common Carotid Artery Occlusion

OBJECTIVE

To investigate the effect of carotid-carotid artery crossover bypass with a synthetic vascular graft for symptomatic type 1A common carotid artery occlusion (CCAO).

METHODS

A retrospective analysis was conducted of patients with symptomatic type 1A CCAO who underwent carotid-carotid artery crossover bypass surgery via a retropharyngeal route with a synthetic vascular graft in the Department of Neurosurgery at our hospital. Preoperative demographic data, surgical complications, incidence of stroke during follow-up, and other clinical data were summarized.

RESULTS

Between 2011 and 2016, carotid-carotid artery crossover bypass was performed with a synthetic vascular graft in 4 patients with type 1A CCAO. The mean patient age was 63.3 years (range, 49-69 years). Clinical symptoms included dizziness, amaurosis fugax, persistent limb numbness, and transient ischemic attack. In all 4 patients, postoperative computed tomography angiography showed internal carotid artery thickening due to successful bypass, whereas computed tomography perfusion showed improved postoperative cerebral perfusion on the side of the lesion. The sole perioperative complication was a complaint of foreign body sensation on swallowing in 1 patient. The mean duration of follow-up was 40.3 months (range, 14-77 months), during which no newly occurred cerebral ischemia or synthetic vascular graft occlusion was observed.

CONCLUSIONS

Carotid-carotid artery crossover bypass with a synthetic vascular graft is a safe and effective therapeutic approach for patients with symptomatic type 1A CCAO. However, studies with larger series are needed to enable more precise conclusions.

Modification to the Rice-Vannucci perinatal hypoxic-ischaemic encephalopathy model in the P7 rat improves the reliability of cerebral infarct development after 48hours

BACKGROUND

The Rice-Vannucci model of hypoxic-ischaemic encephalopathy (HIE) has been associated with a high degree of variability with respect to the development of cerebral infarction and infarct lesion volume. For this reason, we examined the occurrence of communicational blood flow within the common carotid (CCA), internal (ICA), and external (ECA) carotid arteries following CCA occlusion as a source of variability in the model.

NEW METHOD

We propose a novel modification to the Rice-Vannucci model, whereby both the CCA and ECA are permanently ligated; mitigating communicational blood flow.

RESULTS

Using magnetic resonance angiography, phase-contrast velocity encoding, and pulsed arterial spin labelling, the modified Rice-Vannucci model (CCA/ECA occlusion) was demonstrated to mitigate communicational blood flow, whilst significantly reducing ipsilateral hemispherical cerebral blood flow (CBF). Comparatively, the original Rice-Vannucci model (CCA occlusion) demonstrated anterograde and retrograde blood flow within the ICA and CCA, respectively, with a non-significant reduction in ipsilateral CBF. Furthermore, CCA/ECA occlusion plus hypoxia (8% O₂/92% N₂; 2.5h) resulted in 100% of animals presenting with an infarct (vs 87%), significantly larger infarct volume at 48h (18.5% versus 10.0%; p<0.01), reduced standard deviation (±10% versus ±15%), and significantly worsened functional outcomes when compared to CCA occlusion plus hypoxia.

COMPARISON WITH EXISTING METHOD

We compared a modified Rice-Vannucci model (CCA/ECA occlusion±hypoxia) to the commonly used Rice-Vannucci model (CCA occlusion±hypoxia).

CONCLUSION

This study demonstrates that CCA/ECA occlusion in the Rice-Vannucci model of HIE reduces infarct volume variability by limiting communicational blood flow.

Adaptation of the cerebrocortical circulation to carotid artery occlusion involves blood flow redistribution between cortical regions and is independent of eNOS

Cerebral circulation is secured by feed-forward and feed-back control pathways to maintain and eventually reestablish the optimal oxygen and nutrient supply of neurons in case of disturbances of the cardiovascular system. Using the high temporal and spatial resolution of laser-speckle imaging we aimed to analyze the pattern of cerebrocortical blood flow (CoBF) changes after unilateral (left) carotid artery occlusion (CAO) in anesthetized mice to evaluate the contribution of macrovascular (circle of Willis) vs. pial collateral vessels as well as that of endothelial nitric oxide synthase (eNOS) to the cerebrovascular adaptation to CAO. In wild-type mice CoBF reduction in the left temporal cortex started immediately after CAO, reaching its maximum (-26%) at 5-10 s. Thereafter, CoBF recovered close to the preocclusion level within 30 s indicating the activation of feed-back pathway(s). Interestingly, the frontoparietal cerebrocortical regions also showed CoBF reduction in the left (-17-19%) but not in the right hemisphere, although these brain areas receive their blood supply from the common azygos anterior cerebral artery in mice. In eNOS-deficient animals the acute CoBF reduction after CAO was unaltered, and the recovery was even accelerated compared with controls. These results indicate that 1) the Willis circle alone is not sufficient to provide an immediate compensation for the loss of one carotid artery, 2) pial collaterals attenuate the ischemia of the temporal cortex ipsilateral to CAO at the expense of the blood supply of the frontoparietal region, and 3) eNOS, surprisingly, does not play an important role in this CoBF redistribution.

The effect of regular exercise on antioxidant enzyme activities and lipid peroxidation levels in both hippocampi after occluding one carotid in rat

Regular exercise has beneficial effects on cerebrovascular diseases; however, its biochemical mechanisms are not fully known. The purpose of this study was to determine antioxidant enzyme activities and lipid peroxidation of both hippocampi after applying exercise followed by occluding one common carotid. Wistar rats were divided into four groups of control, exercise, hypoperfusion and exercise-hypoperfusion (exe-hypo). In the exercise and exe-hypo groups, the rats were forced to run on a treadmill for 1 h a day for 2 months. The right common carotid of the animals in the (exe-hypo) group was occluded after the cessation of exercise. Surgery without occlusion of the carotid was applied on the control (without exercise) and exercise groups. All animals were sacrificed 1 and 24 h after surgery. The levels of malondialdehyde (MDA) and antioxidant enzyme activities in the hippocampi were measured. A significant interaction was observed between the exercise and hypoperfusion in both hippocampi (p<0.05). In comparison with the control group, there was significant elevation of catalase activity in the right and left hippocampus of the hypo group at 24 h (p<0.0001). Regarding the differences between the hemispheres, there was a significant increase in MDA and decrease in catalase activity in the left hippocampus in hypoperfusion group, but the exercise in the exe-hypo group succeeded in abolishing these alterations which were caused by hypoperfusion, This study shows that exercise pre-conditioning prevents some alterations in brain oxidant-antioxidant status which are induced by cerebral hypoperfusion. Further studies are needed in order to clarify the mechanism of exercise.