1. DR. Ahmed Abanamy Hospital DOCTOR Nazih Mohammed Alothman Vascular Surgeon

2. ATHEROSCLEROSIS OF CAROTID ARTERY

3.  Stroke is the primary cause of disability and third most common cause of death in U.S.A.  Atherosclerosis occlusive disease of extra cranial carotid artery is a major risk for stroke,which accounts 90% of lesion in extra cranial system.  Atheromatous lesions characteristically occur at branches of arterial bifurcations. Introduction

5.  The point of take-off branches of the aortic arch.  The origin of vertebral artery.  The bifurcation of common carotid artery.  The carotid siphon.  The origins of anterior &middle cerebral artery ACA-MCA. Common sites include Extra cranial : intracranial lesions = 2:1

6.  Fibro muscular dysplasia  Arterial kinking as result of elongations  Extrinsic compression  Traumatic occlusion  Intimal dissection  Inflammatory angiopathy  Migraine  Radiation  Other rare entities : fibrinoid necrosis -amyloidosis - allergic angiitis. differential diagnosis

7. pathology Tow theories emerged as explanation for TIA

8.  Crawford and Coworkers stated that the criterion for carotid endarterectomy should be the presence of pressure gradient across stenosis which decreased flow.  TIA may result from intermittent episode of systemic hypotension or decreased cardiac output in patient with stenosed or occluded cerebral arteries. The arterial stenosis theory

9. The fact that Atheromatous plaques can be a source of emboli was first reported by Ponum in 1862. The cerebral emboli theory

10.  Ulcerated plaque at carotid bifurcation can releases emboli, where they pass retrograde via collateral communication to ophthalmic artery then to carotid siphon and into MCA.  Emboli can reach hemisphere ipsilateral to an internal carotid artery occlusion from opposite carotid artery or from the vertebral-basilar system.  One variant of posterior circulation ischemia occur with subclavian steal syndrome.  Intra cerebral thrombosis is caused by intra cranial atheromatosis or by thrombus from the internal carotid artery distal to proximal Atheromatous stenosis.  Sudden intra plaque hemorrhage produced an acute occlusion.

11. Diagnosis

12. ULTRASOUND

13. with B mode imaging is important to:  determine whether the patient is a candidate for carotid endarterectomy.  detect and characterize atherombotic plaque  measure intima,midia thickness.  level of stenosis (mild :<50%, moderate :50-69%, sever :7O-99%, occluded :100% ). it cannot differences between 99% stenosis and occlusion Carotid duplex

15.  provide additional information on flow dynamics presence or absence of collateral circulation and central vascular reserve  detect emboli in MCA. Trans cranial Doppler (TCD)

16.  Has a combined mortality and morbidity of 0.5-4% in patient with atherosclerosis.  Cerebral angiography is the most complete preoperative study for anatomic delineation of the carotid arteries and their intracranial branches.  In the patient considered a candidate for carotid endarterectomy, a full angiographic examination includes bilateral visualization of the extra cranial arteries, evaluation of # hemispheric blood flow # and aortic arch imaging # Selective views are added to aid in the diagnosis of ulcerative lesions # additional information on the vertebrobasilar system # rule out other causes of neurologic symptoms, such as siphon and branch stenoses, cerebral aneurysms, tumors, and arteriovenous malformation. ANGIOGRAPHY

17.  Still has limitation due to overestimation of degree of stenosis and production of flow artifacts.  Combination of both MR imaging and carotid duplex can provide accurate diagnosis of carotid stenosis and plaque size no invasively. MR IMAGINGRAPHY

18. Management

19.  No drug therapy has been shown to reduce the risk of stroke in patient with asymptomatic carotid disease.  Medical management in symptomatic patient is focused on antiplatelet agent.  Aspirin is affective in reducing stroke and stroke related death  Low doses (80 mg per day )are as efficacious as higher doses (1,200 mg per day ).  Other antiplatelet agent such as (dipyridamol – ticlopidine) are no better than aspirin alone.  Anticoagulation with heparin sodium is beneficial in patient who have cardiac emboli and in evolving stroke to prevents progression of thrombus.  There is reduction in stroke risk for patient with 50-99% intracranial stenosis on warfarin compared to aspirin. Medical therapy

20. Surgical therapy indication for surgical repair

21. The risk of stroke is 3-5%per year. Operative mortality and morbidity rate is 3% And The average late stroke is 0.3 % per year. Asymptomatic carotid stenosis > 75%

22. Ulcers has been divided into  A ulcer : <10mm2 – no surgery.  B ulcer : 10-49mm2 – depend on the experience of surgical team and importance of lesion.  C ulcer : > 40 mm2. cavernous compound surgical reaper (the stroke rate is 7.5% per year). Asymptomatic carotid stenosis with ulceration

23.  Symptomatic patient with >70 % stenosis  Symptomatic patient with >50 % stenosis Who has an ulcerated or symptoms persist while they are on aspirin.  Selected patient with stroke in evolution Mild to moderate neurological defect and no hemorrhage on CT. the time of surgery is controversial.  Selected patient with complete stroke the candidation of surgery: - >70% stenosis. - >50% stenosis and ulcer. - <70% stenosis and contra lateral occluded carotid artery the time of operation is 4-6 weeks later to minimize the risk of postoperative hemorrhage.

24.  Who has undergone endarterectomy and develop immediate postoperative thrombosis or symptoms.  Asymptomatic patient and has had a bruit disappear while under observation or progressive symptoms.  symptomatic patient and has a new internal carotid occlusion that can be operated within 2-4 hours of onset of symptoms. rarely in acute patient with completely occluded carotid artery

25. 1.Serious illness. 2.Major stroke and not yet began to recover 3.Major stroke in the past and is so divested by neurological dysfunction or altered consciousness that operation is advisable. 4.Acute stroke. CONTRAINDICATION TO SURGERY

26. operation technique

27.  Allow the surgeon to evaluate the patient's cerebral tolerance to carotid clamping.  Disadvantages relate to anxiety, restless and agitation of patient and extended operation. SURGERY OF CAROTID BIFURCATION Local anesthesia

28.  Control of patient's airway and ventilator.  Halogenated agents can increase cerebral blood flow decrease cerebral metabolic.  Comfortably surgical team without disturbing the operation field. General anesthesia

29. supine,with neck slightly hyper extended, and gently turned to side opposite that of operation. flexing the operation table 10-20 degree position

30. incision

31.  It parallels the carotid artery  Extension of incision is simple and easy vertical incision

32. More acceptable scar It necessary to raise skin flaps More difficult to gain additional exposure Carotid sheathe is incised low on the neck Common facial vein is landmark for carotid bifurcation. oblique incision

33. 1-2 ml of 1% lidocain may be injected into the tissue between the external and internal carotid arteries to block the nerves to carotid sinus. We must preserve : The superior thyroid artery, and ascending pharyngeal artery, and 12 th cranial nerve which passed obliquely just superior to the bulb of the carotid a. CAROTID CROSS-CLAMPING : 85-90% of patient have adequate cerebral collateral circulation. General anesthesia prefer to an internal artery shunt. Complication of insert shunt : - scuffing and disruption intima. - introduction of air or thrombolic emboli. Patient without shunt has a post operation neurological complication rate 1.5%, whereas those with shunt 5%.

34. MONITORING PATIENT UNDER GENERAL ESTHESIA : 1.Measurement of ipsilateral jugular venous oxygenation. 2.Electroencephalography. 3.Back-flow from internal carotid artery. 4.Internal carotid back-flow pressure (>25mmhg

35. Hematoma Infection Complications of Carotid Endarterectomy Carotid artery Disruption False aneurysm Carotid-cavernous arteriovenous fistula Graft infection Cranial nerve injury Embolism Cerebral ischemia

36.  Stroke  Thrombosis of endarterectomized segment  Hypotension  Hypertension  Myocardial infarction  Recurrent stenosis Postoperative period

37. DR. nazih Mohammed al -othman thanks