Carotid artery stenosis is a series of clinical manifestations caused by narrowing of the carotid lumen due to various causes resulting in altered carotid hemodynamics. The cause is mostly atherosclerotic occlusive disease, followed by head and arm type multiple aortitis.
In atherosclerotic-occlusive carotid stenosis, the common carotid artery bifurcation is the most common site, followed by the beginning of the common carotid artery. It is mostly seen in middle-aged and elderly people.
Cephalothoracic multiple aortitis can involve the entire carotid artery, often in a segmental pattern. It is most commonly seen in adolescents, with a predominance of females. The lesions can cause luminal narrowing to complete occlusion, and can be followed by thrombosis. The disease is aggravated by the combination of subclavian artery steal syndrome or vertebral artery lesions.
Clinical manifestations.
Symptoms.
1. Cerebral ischemic symptoms: there may be tinnitus, blurred vision, dizziness, headache, memory loss, drowsiness or insomnia, and dreaminess. There can also be transient cerebral ischemic attacks such as vertigo, blackout, and in severe cases, episodic syncope or even hemiplegia, aphasia, coma, and in a few patients, vision loss, hemianopia, diplopia, or even sudden blindness. Carotid artery stenosis can later cause ischemic manifestations in the eye, such as corneal leukomalacia, cataract, iris atrophy, retinal atrophy or pigmentation, optic disc atrophy, and venous hemorrhage. Patients’ blindness is mostly caused by cataract.
2.Plaque or thrombus dislodgement can lead to transient cerebral ischemia and cerebral infarction. It is common in atherosclerotic occlusive carotid artery stenosis.
3, multiple aortitis active phase may have general discomfort, fever, easy fatigue, loss of appetite, weight loss, excessive sweating, menstrual irregularities and other symptoms. Sometimes there may be atypical symptoms, such as unexplained fever or pericardial effusion. Skin manifestations include infected skin nodules, erythema nodosum, and gangrenous pyoderma. Some patients may have tuberculosis or rheumatic fever.
Signs: Weak or absent carotid artery pulsations. On auscultation a murmur can be heard at the root of the neck and in the carotid artery line. Other parts of the artery should also be noted. Neurological examination can have positive signs and help to understand the degree and location of cerebral ischemia. Funduscopic examination can reveal the condition of intracranial arteries.
Auxiliary examinations
1.Arteriogram: It is the main examination means. The site, scope and extent of the lesion as well as the formation of collateral branches can be understood in detail. It provides the most valuable imaging basis for surgery or interventional treatment.
2.B ultrasound-Doppler examination: It is the best non-invasive examination instrument for carotid artery. It can not only show the anatomical image of carotid artery, but also show the intra-arterial thrombus and blood flow, flow rate and direction of blood flow. The accuracy of diagnosing the degree of carotid artery patency is over 95%. Trans-Doppler can evaluate the blood flow and direction of blood flow in Wills’ loop.
3.Doppler ultrasonography: Tracing the waveform of carotid artery boom, the blood flow of supraorbital artery can be measured, and the blood supply of intracranial artery can be understood indirectly, so as to presume whether the carotid artery is narrowed or occluded.
4.Cerebral hemogram: shows a significant decrease in cerebral blood flow
5.MRA: It is a non-invasive vascular imaging technique, which can clearly display the three-dimensional morphology and structure of the carotid artery and its branches, and can simultaneously reconstruct the intracranial arterial image. It can show exactly the thrombus, plaque, the presence or absence of clotted aneurysm and the condition of intracranial arteries. It has great reference value for early lesions of the intima and wall of the artery, and is extremely helpful for diagnosis and determination of treatment plan.
6.Eye fundus examination
7.X-ray plain film examination
8.Other: For immunological examination of aortitis.
Diagnosis: Carotid artery stenosis can be mostly diagnosed through clinical manifestations and non-invasive auxiliary examinations. And the preliminary etiological diagnosis can be completed. However, arteriography is essential to confirm the diagnosis and to develop the basis of treatment plan.
Treatment.
The aim is to improve cerebral blood supply and correct or relieve the symptoms of cerebral ischemia: to prevent the occurrence of strokes.
The methods of treatment are: conservative treatment: surgical treatment and interventional treatment.
1. Conservative treatment: It is the basis of surgical treatment and interventional treatment. It includes anticoagulation, depolymerization therapy, poppy bases and nimodipine vasodilation therapy: prostaglandin E1 and fibrin-lowering drugs, energy combination and hyperbaric chamber application, as well as etiology-specific drug therapy. Patients with active aortitis, the application of hormones or immunosuppressants and other drugs to control the course of the disease.
2.Surgical treatment.
A Endarterectomy: Applicable to patients whose pathology is due to atherosclerotic occlusion. The lesion is located in the bifurcation of the common carotid artery or the beginning of the internal carotid artery, while the distal internal carotid artery is open.
B Subclavian artery-carotid artery diversion. For patients with obstruction at the beginning of the common carotid artery and a patent distal carotid artery, with blood flow reperfused to the carotid artery via the subclavian artery.
C Ascending aorta – carotid artery diversion. Applicable to patients with unilateral or bilateral carotid artery lesions, with a patent distal outflow tract and able to tolerate open-heart surgery, single and bilateral subclavian artery diversion can be performed simultaneously.
3.Interventional therapy: In recent years, interventional therapy has been widely used in the treatment of carotid artery stenosis at home and abroad.
Advantages.
Minimally invasive, simple, easy to perform and repeatedly applied, a number of scholars have listed intervention as the preferred treatment method.
In patients with severe carotid artery stenosis, the lesions mostly involve bilateral carotid arteries, and the arterial lumen stenosis is so severe that it cannot tolerate cerebral ischemia during surgery.
Some patients are critically ill with poor general condition and cannot tolerate the blow of arterial reconstruction surgery, when interventional treatment can effectively increase the blood supply to the brain and relieve ischemic symptoms
Disadvantages.
The gyroscopic nature of the embolus during interventional therapy is the main reason limiting its widespread use in the treatment of carotid artery stenosis.