Carotid disease |
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The carotid arteries run on each side of the neck and supply the brain with blood. These often become furred up and this causes a narrowing of the carotid artery. These can cause mini - strokes (transient ischaemic attacks) or a full blown stroke. This can be prevented by a simple operation called carotid endarterectomy. Carotid Endarterectomy: 1
Carotid endarterectomy, pioneered by Dr. (Sir) Charles Rob, remains a durable operation for atherosclerotic carotid disease. Symptomatic plaque throwing emboli or reaching critical stenosis (50-70%) are clear indications. With asymptomatic significant stenoses operated by experienced surgeons, the benefits probably outweigh morbidity. Carotid Endarterectomy: 2
The incision is deepened through platysma and the investing layer of deep cervical fascia at the edge of the sternocleidomastoid muscle. The muscle is bluntly dissected off the loose underlying carotid sheath exposing the internal jugular vein. Carotid Endarterectomy: 3
The carotid sheath is opened, the common facial vein crossing the carotid bifurcation is ligated and divided, and the internal jugular vein is gently retracted posteriorly. The ansa hypoglossi may be mobilized out of the way or may be divided without significant consequences. The internal and external carotid origins are visualized along with the origin of the superior thyroid artery. The hypoglossal nerve is visualized high in the field along with the vagus nerve deep between the vessels. Carotid Endarterectomy: 4
Vessel loops are tightened for proximal and distal control around soft portions of the vessel. Some surgeons use angled Pott's clamps for this purpose but these are slightly more traumatic and cannot be used with a shunt. An incision is started with an 11 blade in the common carotid and carried up along the internal carotid with angled Pott's scissors. Carotid Endarterectomy: 6
The use of a shunt allows more time for careful dissection by maintaining normal cerebral blood flow and decreasing the risk of CVA. Many excellent surgeons use it routinely, especially in training programs, and many use it selectively, especially if their clamp time is routinely under 10 minutes. Measurement of stump pressure indicating degree of flow across the circle of Willis provides some guidance for whether to shunt. Criteria vary among surgeons, 40mm of Hg generally being considered a minimal safe pressure. The shunt is looped or bowed with a suture sling to provide working room around it. The remaining images are shown without a shunt for clarity.
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