External carotid endarterectomy: indications, technique, and late results

In the past 14 years, 22 patients (25 operated sides), with occlusion of the internal carotid artery (ICA), underwent ipsilateral external carotid artery (ECA) endarterectomy at our institution. Operative indications were amaurosis fugax in 13 sides and nonlateralizing transient ischemic attacks in the remaining 12. There were no operative deaths. One patient suffered a minor stroke after operation. Follow-up ranged from 6 to 110 months (median 36 months). In 16 cases, simple endarterectomy with or without vein patch closure was performed (type I). In two cases the ostium of the ICA was occluded with interrupted sutures after endarterectomy (type II). In the remaining seven cases the ICA was transposed as a patch over the endarterectomized ECA after endarterectomy (type III). All but six patients (six sides) underwent duplex scanning or angiography during follow-up. Four of nine patients with previous nonlateralizing symptoms had persistent symptoms after operation, whereas none of those with previous amaurosis fugax did. Recurrent occlusive disease was more common in type I reconstructions (p less than 0.05). Proper ECA reconstruction results in long-term patency. In the patient with ipsilateral ICA occlusion, transposition of the ICA as a patch over the endarterectomized ECA offers a valid hemodynamic solution. Objective parameters are needed to identify patients with nonlateralizing symptoms who will benefit from operation.     

External carotid endarterectomy in the treatment of symptomatic patients with internal carotid artery occlusion

In patients with internal carotid artery (ICA) occlusion, the external carotid artery (ECA) can be both a source of collateral flow and a pathway for emboli. We identified 11 patients with ICA occlusion and ipsilateral ECA stenosis who underwent ECA endarterectomy to determine its role in treating extracranial cerebrovascular disease. Follow-up ranged from 1–65 months, with a mean of 27 months. Seven of eight patients with unilateral disease remained symptom free. The eighth patient had recurrent symptoms that were subsequently diagnosed as hemi-Parkinsonism. Two of three patients with bilateral occlusive disease had developed non-hemispheric symptoms at 12 and 24 months, respectively; the third remains asymptomatic after extracranial-intracranial bypass. None of the seven patients who presented with amaurosis fugax had recurrent visual symptoms. ECA endarterectomy is a safe and effective operation in treating symptomatic patients with ICA occlusion, especially those with transient monocular blindness or unilateral occlusive disease. It is less effective in those patients who have diffuse bilateral occlusive disease.     

External carotid revascularization: review of a ten-year experience

In the presence of ipsilateral internal carotid artery (ICA) occlusion, external carotid artery (ECA) revascularization can improve cerebral perfusion or eliminate an embolic source. From 1974 through 1984, 37 patients at The Cleveland Clinic underwent 42 ECA reconstructions; autologous patch angioplasty and intraluminal shunting were used when feasible. Thirty procedures were limited to primary ECA revascularization, whereas 12 extended procedures were performed as reoperations after previous ECA endarterectomy or required complementary subclavian or intracranial bypass. There were no early postoperative deaths nor neurologic morbidity in the limited group, but one death, four ipsilateral hemispheric strokes, and one retinal embolism occurred in the extended group. Ten patients have died during a follow-up interval of 1 to 72 months (mean 27 months). Five late deaths were caused by myocardial infarction, only one of which was complicated by a contralateral stroke. Two additional strokes have occurred; one involved the ipsilateral and one the contralateral cerebral hemisphere. Five other patients experienced recurrent cerebral or ocular ischemic symptoms. In conclusion, extended ECA reconstruction is associated with a higher operative risk than limited revascularization. Late follow-up is necessary to detect those patients who may eventually require additional management of recurrent cerebrovascular symptoms or incidental coronary artery disease.     

External carotid artery revascularization: indications, operative techniques and results.

The external carotid artery (ECA) is an important collateral pathway in patients with ipsilateral internal carotid artery (ICA) occlusion and recurrent symptoms. An ipsilateral ECA revascularization can improve cerebral perfusion or eliminate an embolic source. In the past 11 years 11 patients underwent operation, 6 times for amaurosis fugax and 5 times for transient ischaemic attacks. Eight times ECA endarterectomy was performed for stenosis and/or ulceration. Eight times closure or separation of the ICA stump with thrombus was carried out. There were no perioperative neurological deficits or deaths, with the exception of 3 patients who already had a long-standing deficit due to the ICA occlusion. All patients were relieved of their ocular or hemispheric symptoms in a follow-up period of 8 years. Two late strokes occurred after 1 1/4 and 4 years. Ipsilateral ECA revascularization is an effective and safe operation and has good long-term results.     

Safety and efficacy of surgical treatment of carotid stump syndrome: pilot study

Surgical exclusion of the internal carotid artery (ICA) stump combined with endarterectomy of the external carotid artery is an established treatment approach. The aim of this pilot study was to compare the risk of cerebrovascular events between surgical treatment and best medical treatment in patients with ICA occlusion and carotid stump syndrome. Forty patients (23 males; age: 43-80 years; mean age: 61.1 ± 9.0 years) with carotid occlusion and carotid stump syndrome were enrolled. Ten patients with asymptomatic ICA occlusion and 10 patients with symptomatic ICA occlusion and carotid stump syndrome were enrolled to the best medical therapy group. Patients with chronic ICA occlusion, carotid stump syndrome, and one (15 patients) or recurrent (three patients) episodes of ipsilateral stroke or transient ischemic attack were enrolled to the surgical group. Neurological examination was undertaken on the day of randomization and then every 6 months in all patients for 4 years. All vascular events and death were recorded. Only one vascular event occurred in patients with symptomatic ICA occlusion without recurrent stroke or transient ischemic attack who were treated medically. No other vascular event was noted in the other subgroups. One patient with symptomatic carotid occlusion without recurrent stroke died due to myocardial infarction 6 months after surgery. Surgical treatment of carotid stump syndrome seems to be a safe procedure. Nevertheless, the benefit of a surgical approach in comparison with the best medical treatment is not clear.     

Neurologic sequelae of unilateral carotid artery occlusion: immediate and late

Over a 7-year period (1980 to 1987) 24 patients (18 men: mean age 67 years; range, 52 to 78 years, and six women: mean age 67 years; range, 46 to 82 years) undergoing serial carotid artery duplex scans were observed to progress to unilateral carotid artery occlusion. The occlusions were associated with ipsilateral strokes in six (25%), ipsilateral transient ischemic attacks in four (16%), and the onset of nonhemispheric symptoms in one (5%). Thirteen patients had no symptoms. Follow-up ranged from 4 months to 96 months (mean 39.4 months). Late neurologic events comprised two strokes, three transient ischemic attacks and the onset of nonhemispheric symptoms in six, which in some were disabling. Thirteen patients had no symptoms. Three deaths occurred (one was stroke related). For late events by life-table analysis, the average annual rate over the first 2 years for stroke was 10% and for transient ischemic attack 13%. The combined rate for transient ischemic attack and stroke was 20% per annum. For nonhemispheric symptoms the rate for the first year was 31%. It is concluded that unilateral carotid artery occlusion is associated with an unacceptable incidence of immediate neurologic sequelae and that such patients continue to have a high rate of late neurologic deficits at follow-up. Therefore it seems appropriate that patients who are observed to progress to high-grade stenosis and are therefore at risk for immediate occlusion should undergo prophylactic carotid endarterectomy.     

Surgical therapy for recent total occlusion of the internal carotid artery

From January 1980 until May 1983, 24 patients had surgical exploration of the carotid bifurcation for suspected recent total occlusion of the internal carotid artery (ICA). All patients had recent onset of neurologic symptoms related to the ipsilateral cerebral hemisphere. Selective carotid angiography determined preoperative total occlusion of the ICA. Because surgery failed to reopen the ICA in nine patients, they had endarterectomy of the external carotid artery. Fifteen patients had initially successful thromboendarterectomy of the ICA. Prior to patient dismissal, patency was documented by B-mode ultrasound or digital subtraction angiography (DSA). All 15 patients had another B-mode ultrasound scan or DSA at least 45 days after thromboendarterectomy. On reexamination four ICAs were reoccluded, but only one patient became symptomatic. There were no operative deaths and no increase in preoperative neurologic deficits. The natural history of patients with total occlusion of the ICA is variable. The most important factor influencing a therapeutic decision is the patient's neurologic status. This study supports an aggressive, early surgical intervention for recent total occlusion in carefully selected patients.     

Skull base resection with cervical-to-petrous carotid artery bypass to facilitate repair of distal internal carotid artery lesions.

PURPOSE: To demonstrate a direct operative approach to vascular lesions of the internal carotid artery (ICA) at the level of the skull base. METHODS: Between January 1993 and October 1999, five patients underwent lateral skull base resection with cervical-to-petrous carotid artery saphenous vein bypass for repair of distal ICA lesions. This report describes operative methods, morbidity, graft patency, and long-term outcome with this experience. RESULTS: Of the five patients with skull base ICA lesions, all had aneurysmal disease. Three were atherosclerotic and two were dysplastic. Preoperative neurologic symptoms including transient ischemic attacks (2) and Horner's syndrome with vascular headaches (1) were completely resolved after operation. Preoperative dysphagia (2) was resolved in one patient and clinically improved in the other. Postoperative complications included transient paresis in the cranial nerve (CN) VII distribution, as well as permanent loss of the eustachian tube and chorda tympani nerve in all five patients. One patient had lasting paresis in the CN XI distribution as well as a mild stroke resulting in arm weakness. No residual arm weakness was detected at one year. There were no graft occlusions by duplex ultrasound at 45.8 months mean objective follow-up, and no ipsilateral stroke or mortality at 51.2 months mean clinical follow-up. CONCLUSIONS: Saphenous vein bypass from the cervical-to-petrous ICA is technically feasible and provides a valuable reconstruction option for patients with skull base ICA lesions.     

Revascularization of the external carotid artery

Numerous reports describe the relative effectiveness of external carotid artery (ECA) revascularization in patients with ipsilateral internal carotid artery occlusion. Most, however, suffer from small numbers of patients or lack of detailed follow-up data. In addition, controversy persists regarding the safety with which this procedure can be performed. Twenty-two patients underwent a total of 27 ECA revascularizations. There were no perioperative strokes or deaths. During a mean follow-up period of 46 months, no strokes occurred and only two patients suffered transient ischemic attacks. Revascularization of the ECA is an effective means of treating the patient with ipsilateral internal carotid artery occlusion and may be performed with minimal morbidity and mortality.     

Carotid angioplasty with internal carotid artery flow reversal is well tolerated in the awake patient

OBJECTIVE: The purpose of this study was to evaluate the neurologic tolerance and changes in ipsilateral hemispheric oxygen saturation during transcervical carotid artery stenting with internal carotid artery (ICA) flow reversal for embolic protection. PATIENTS AND METHODS: This was a prospective study of 10 patients (mean age 68 years) undergoing transcervical carotid angioplasty and stenting. All ICA stenoses were greater that 70%. Seven patients had an ipsilateral hemispheric stroke (3) or transient ischemic attack (4), two patients had a contralateral stroke, and one patient was asymptomatic. Nine procedures were done under local anesthesia. Cerebral protection was established through a cervical common carotid (CCA) cutdown to create an external fistula between the ICA and the internal jugular vein with temporally CCA occlusion. Venous oxygen saturation (SVO(2)) was continuously monitored through a catheter placed in the distal internal jugular vein. Mental status and motor-sensory changes were categorized and assessed throughout and after the procedure. RESULTS: All procedures were technically successful without significant residual stenosis. Mean ICA flow reversal time was 22 minutes (range, 15 to 32). Common carotid artery (CCA) occlusion produced a slight (SVO(2) = 72.6%+/-9.4) but significant decrease (P =.012) in SVO(2), compared with baseline (SVO(2) = 77% +/-10.5). During ICA flow reversal (SVO(2) = 72.4% +/-10.1) cerebral oxygen saturation did not change compared with CCA occlusion alone (P =.85). Transient balloon occlusion during angioplasty of the ICA (SVO(2) = 64.6%+/-12.9) produced a significant decrease in cerebral SVO(2) compared with CCA occlusion (P =.015) and compared with CCA occlusion with ICA flow reversal (P =.018). No mental status changes or ipsilateral hemispheric focal symptoms occurred during CCA occlusion with ICA flow reversal. One patient with contralateral ICA occlusion sustained brief upper extremity weakness related to the contralateral hemisphere. Five patients sustained a vasovagal response during balloon dilatation, four did not require treatment, and one had asystole requiring atropine injection. Mean SVO(2) saturation was not different in these five patients compared with the five who did not sustain a vasovagal response. No deaths or neurologic deficits occurred within 30 days after the procedure. CONCLUSIONS: Our data suggest that transcervical carotid angioplasty and stenting with ICA flow reversal is well tolerated in the awake patient, even in the presence of symptomatic carotid artery disease. Cerebral oxygenation during ICA flow reversal is comparable to that during CCA occlusion. ICA angioplasty balloon inflation produces a decrease in cerebral SVO(2) significantly greater than that occurring during ICA flow reversal.     

External carotid artery reconstruction: its role in the treatment of cerebral ischemia

Twenty-one patients who underwent 22 external carotid artery reconstructions for cerebral ischemia were reviewed. Ten patients had amaurosis fugax, 9 had hemispheric ischemia, and 2 were asymptomatic. With the exception of one patient, all had ipsilateral internal carotid artery occlusion and either external carotid stenosis or a cul-de-sac of the occluded internal carotid artery. Six patients had ipsilateral common carotid occlusions. The operative technique has been presented. There were no operative strokes or new neurologic deficits. All patients were relieved of symptoms. Patients were followed a mean of 32 months. During follow-up, 3 ipsilateral transient ischemic attacks occurred during the first 3 months. Four strokes occurred (one ipsilateral and three contralateral) from 4 to 33 months postoperatively. Ipsilateral stroke rate by life table analysis was 1 percent per year. These data suggest that external carotid artery reconstruction is a safe, effective, and durable therapeutic alternative for management of patients with cerebral ischemia and an ipsilateral occluded internal carotid artery. External carotid endarterectomy eliminates a potential source of emboli and increases cerebral perfusion. Because of the increase in cerebral blood flow, subsequent extracranial-to-intracranial bypass may be unnecessary.     

Intraoperative duplex ultrasonography as an adjunct to technical excellence in 100 consecutive carotid endarterectomies

PURPOSE: To evaluate the relationship of intraoperative duplex ultrasonography (duplex) results to neurologic outcomes and restenosis among patients undergoing carotid endarterectomy (CEA). METHODS: One hundred consecutive CEAs were performed at a military medical center over 28 months. Prospectively acquired demographics, duplex results, revisions, and surgical outcomes were reviewed. RESULTS: Thirty-four percent (34 of 100) of sites were abnormal by completion duplex. Of these, 70% (24 of 34) were B-mode flap type defects located in the common carotid artery (CCA), internal carotid artery (ICA), or external carotid artery (ECA). Twenty-one percent of the defects (7 of 34) were technically unacceptable and immediately revised. Subsequently, 3 perioperative neurologic events occurred, 2 strokes and 1 transient ischemic attack (TIA), all among patients with an identified but unrepaired defect involving the ICA or CCA. This association of unrepaired defect with early stroke or TIA was significant (P = 0.02). No significant association (P >0.05) between unrepaired defects and late ipsilateral stroke or TIA or restenosis was identified. CONCLUSIONS: Intraoperative duplex scanning is a useful adjunct to CEA that can identify correctable mechanical problems. Residual elevated velocities or B-mode flaps 2 mm or greater in the ICA warrant consideration for immediate repair. Findings not requiring revision include flaps <2 mm, as well as isolated ECA defects. Prospectively validated duplex criteria are needed to further define which defects require immediate repair.     

Progression of asymptomatic carotid stenosis: A natural history study in 1004 patients

Purpose: The purpose of this study was to delineate the natural history of the progression of asymptomatic carotid stenosis. Methods: In a 10-year period, 1701 carotid arteries in 1004 patients who were asymptomatic were studied with serial duplex scans (mean follow-up period, 28 months; mean number of scans, 2.9/patient). At each visit, stenoses of the internal carotid artery (ICA) and the external carotid artery (ECA) were categorized as none (0 to 14%), mild (15% to 49%), moderate (50% to 79%), severe (80% to 99%), preocclusive, or occluded. Progression was defined as an increase in ICA stenosis to ≥50% for carotid arteries with a baseline of <50% or as an increase to a higher category of stenosis if the baseline stenosis was ≥50%. The Cox proportional hazards model was used for data analysis. Results: The risk of progression of ICA stenosis increased steadily with time (annualized risk of progression, 9.3%). With multivariate modeling, the four most important variables that affected the progression (P < .02) were baseline ipsilateral ICA stenosis ≥50% (relative risk [RR], 3.34), baseline ipsilateral ECA stenosis ≥50% (RR, 1.51), baseline contralateral ICA stenosis ≥50% (RR, 1.41), and systolic pressure more than 160 mm Hg (RR, 1.37). Ipsilateral neurologic ischemic events (stroke/transient ischemic attack) occurred in association with 14.0% of the carotid arteries that were studied. The progression of ICA stenosis correlated with these events (P < .001), but baseline ICA stenosis was not a significant predictor. Conclusion: In contrast to recently published studies, we found that the risk of progression of carotid stenosis is substantial and increases steadily with time. Baseline ICA stenosis was the most important predictor of the progression, but baseline ECA stenosis also was identified as an important independent predictor. Contralateral ICA stenosis and systolic hypertension were additional significant predictors. We found further that the progression of ICA stenosis correlated with ischemic neurologic events but not baseline stenosis. The data provide justification for the use of serial duplex scans to follow carotid stenosis and suggest that different follow-up intervals may be appropriate for different patient subgroups. (J Vasc Surg 1999;29:208-16.)     

The risk of stroke with occlusion of the internal carotid artery

Reports of all cervicocephalic arteriograms (n = 1836) performed at one institution during a 10-year period were reviewed and the patients were classified into three groups according to the indication for arteriography. Group I included all patients with symptoms or findings compatible with occlusive disease of the carotid or vertebral artery (n = 806). Group II included patients with cerebrovascular symptoms unrelated to carotid or vertebral disease (e.g., patients with subarachnoid hemorrhage) (n = 367). Group III consisted of patients with no evidence of cerebrovascular disease (e.g., patients with primary and metastatic brain tumors) (n = 663). One hundred ten atherosclerotic occlusions of the internal carotid artery (ICA) were found in 106 patients in group I. Fifty-one percent of these patients had a history of stroke before arteriography, 24% had transient ischemic attacks (TIAs) or amaurosis fugax (AF), and 12% had nonhemispheric symptoms. Only 13% (1.7% of group I patients) were without symptoms. Ninety-one percent of the strokes and 75% of the TIAs or AF were ipsilateral to the ICA occlusion. Seventy-six percent of patients with stroke and 80% with ipsilateral TIAs or AF vs only 29% of patients without symptoms had contralateral stenosis of 60% diameter reduction or greater (p less than 0.003). No occlusions of the ICA occurred in groups II or III. Three hundred forty-six patients in groups II and III were more than 60 years of age. Assuming either Poisson or binomial distributions, the incidence of silent ICA occlusion in the population at large older than 60 years was estimated at less than 1% (p less than 0.03).     

The role of external carotid endarterectomy in the treatment of ipsilateral internal carotid occlusion: collective review

Complete occlusion of the internal carotid artery (ICA) may result in a variety of clinical states. Neurologic symptoms in the setting of ICA occlusion may be due to embolic events through the external carotid artery (ECA) circulation, hemodynamic insufficiency resulting from inadequate collateral development, or propagation of clot intracranially. External carotid reconstruction has been used to prevent neurologic events from the first two mechanisms. This review attempts to place in perspective the current indications for, techniques of, and results from ECA revascularization. A discussion of the cerebral collateral circulation is included for reference. Twenty-three series were collected from the literature. Cases were excluded in which procedures other than ECA reconstruction were undertaken, leaving 218 cases for analysis. These represented 195 EC endarterectomies and 23 ECA bypasses. Resolution of symptoms was seen in 83% of patients with another 7% showing marked improvement. The perioperative mortality rate was 3%; neurologic deaths accounted for most perioperative deaths. The overall neurologic complication rate was 5%. More recent reports were notable for improved mortality and morbidity. A diseased contralateral carotid artery was associated with higher neurologic morbidity whereas disease in the vertebral arteries had no impact on outcome. The best results were obtained when surgery was performed to relieve specific hemispheric or retinal symptoms as opposed to nonspecific neurologic complaints or previous stroke. The symptomatic patient with ICA occlusion has a poor neurologic prognosis. In selected circumstances ECA reconstruction should be considered among the treatment options in this clinical setting.     

Hemodynamic conditions at the carotid bifurcation during protective common carotid occlusion.

OBJECTIVES: Carotid angioplasty and stenting procedures are associated with an obligatory release of particulate debris into the distal cerebral circulation. Although most of the emboli are small and do not result in symptomatic neurologic deficits, some may be large enough to cause stroke. For this reason, a variety of filters and balloon occlusion devices have been employed as adjuvants to decrease the risk of distal embolization during carotid stenting. Some of these devices rely on the arrest of antegrade blood flow with the use of inflow arrest. The present study was undertaken to investigate the hemodynamic conditions that exist at the carotid bifurcation during common carotid artery (CCA) occlusion. METHODS: Internal carotid artery (ICA) and external carotid artery (ECA) stump pressures were measured in 29 patients undergoing carotid endarterectomy. Duplex ultrasound scanning was used to measure the direction and velocity of blood flow in the ICA and ECA with the CCA cross-clamped but the ICA and ECA open, a clinical scenario analogous to CCA balloon occlusion at the time of carotid angioplasty and stenting. The direction and magnitude of ICA and ECA flow were compared with the stump pressures to determine whether a correlation existed between these variables. RESULTS: The mean stump pressure in the ICA and ECA averaged 56 +/- 16 and 53 +/- 12 mm Hg, respectively. The ICA systolic stump pressure was lower than the ECA systolic stump pressure in six patients (21%), and all of these patients had persistent antegrade systolic duplex blood flow by duplex interrogation during CCA occlusion. The ICA systolic stump pressure exceeded the ECA systolic stump pressure in 19 patients (66%), and all of these patients had retrograde ICA flow during systole. Diastolic flow was also well correlated with the magnitude of the ICA/ECA stump pressure differential, with antegrade diastolic ICA blood flow in all nine patients with an ICA diastolic stump pressure less than the ECA diastolic stump pressure. None of the 10 patients with ICA diastolic stump pressure greater than ICA diastolic stump pressure maintained antegrade ICA diastolic flow, but four of these patients had flow to zero in diastole. Overall, 13 of 29 patients (45%) could be surmised to be at risk for distal embolization to the brain based on the persistence of some element of either systolic or diastolic antegrade ICA flow during common carotid occlusion. CONCLUSIONS: Common carotid occlusion alone appears insufficient to protect against distal embolization during manipulations of the carotid bifurcation. Persistent systolic or diastolic antegrade blood flow occurs in a high proportion of patients, lending credence to the use of additional protective strategies to ameliorate the risk of embolic complications.     

Protection of anastomotic pathways to the vertebral artery during stenting of external carotid artery stenosis

A 61-year-old man presented with a severe external carotid artery (ECA) stenosis with concomitant ipsilateral internal carotid artery (ICA) occlusion manifesting as amaurosis fugax. The left ophthalmic artery was supplied from the left ECA. The left intracranial ICA was supplied by the collateral flow from the contralateral ICA and ipsilateral ECA through the ophthalmic artery. The left vertebral artery also participated in the latter collateral pathway through the left occipital artery and ascending pharyngeal artery. Percutaneous revascularization of the ECA was performed using a nitinol self-expanding stent. To prevent embolic complications through the ophthalmic or vertebral arteries, distal protection was performed using a balloon. During a 22-month follow-up period, the patient was completely free from any ocular or neurological symptoms. The present case of severe ECA stenosis with ipsilateral ICA occlusion showed that percutaneous balloon angioplasty with stenting is feasible and effective. This intervention requires cautious evaluation of the anastomotic pathways connecting the ECA to the cerebral circulation to avoid embolic complications.     

Effect of carotid artery stenting on the external carotid artery

OBJECTIVE: We studied the fate of the ipsilateral external carotid artery (ECA) after stenting of the internal carotid artery (ICA) compared with the contralateral ECA. SUBJECTS AND METHODS: One hundred twenty-one ipsilateral ECAs in 112 consecutive patients who underwent carotid artery Wallstent placement were prospectively studied with color-coded duplex sonographic scanning (CCDS) and compared with 83 contralateral ECAs over 2 years. CCDS was scheduled for the day before (day 0), the day after (day 1) and 3, 6, 12, and 24 months after stenting. Development of ECA occlusive disease was evaluated with ECA-common carotid artery flow ratio (peak systolic velocity). For estimation of ECA stenosis 70% or greater, flow ratio 4.1 was used as the cutoff point. RESULTS: Before and after stenting, two and three (one additional) ECA occlusions were seen. Median grade of ECA stenosis on day 1 did not significantly change at angiography (P = 1.0; tendency of increase) or CCDS (P =.27; tendency of decrease).At follow-up (day 1-24 months, CCDS only), frequency of stenosis 70% or greater in the ipsilateral ECA was 21 of 120 (17.5%) on day 1 and 41 of 107 (38.32%) at 24 months, and 3 of 107 (2.5%) and 5 of 107 (4.67%) ECA occlusions were registered at the two time points. Progression of disease, as demonstrated by increase in flow ratio over time, was much more pronounced in the ipsilateral ECAs compared with the contralateral ECAs (P =.0002).In stented ICA, 2 (1.85%) asymptomatic recurrent stenoses 70% or greater were found at CCDS.One of three patients with new ECA occlusions reported jaw claudication for 10 days. Perioperative stroke (one major, four minor) occurred in 5 of 121 patients (4.46%). Two minor strokes caused by embolization occurred during the first year. CONCLUSION: The more pronounced progression of arteriosclerotic disease at the orifice of the ipsilateral ECAs during the first year after carotid stenting might be due to local factors of the ICA stent. Its clinical significance in respect to the effect of the ECA as collateral supply to the brain might depend on the incidence of carotid stent rerecurrent stenosis, which was low in the present study.     

Stenosis of the proximal external carotid artery in an adult with moyamoya disease: moyamoya or atherosclerotic change?

A 55-year-old woman presented with moyamoya disease manifesting as recurrent transient ischemic attacks despite taking aspirin and antihypertensive agent. Angiography showed the characteristic angiographic appearance with bilateral internal carotid artery occlusion and abnormal collateral vessels. Left external carotid angiography demonstrated moderate stenosis of the proximal external carotid artery (ECA). A self-expandable stent was successfully placed in the left ECA to improve ipsilateral cerebral perfusion. The patient had an uneventful outcome after a 1-year follow up. Involvement of the proximal ECA is very unusual in moyamoya disease, and might result from hemodynamic stress or degenerative atherosclerosis. Revascularization procedures for stenoses of proximal ECA may improve cerebral perfusion in patients with moyamoya disease.     

Impact of external carotid artery occlusion at declamping of the external and common carotid arteries during carotid endarterectomy on development of new postoperative ischemic cerebral lesions

Objective

The external carotid artery (ECA) is inadvertently occluded during carotid endarterectomy (CEA). The importance of ECA occlusion has been emphasized as a loss of extracranial to intracranial collaterals, a source of chronic embolization, or a site for extended thrombosis during wound closure. This study aimed to determine whether ECA occlusion that inadvertently developed during endarterectomy and that was eventually detected using blood flow measurement of the ECA after declamping of all carotid arteries is a risk factor for development of new postoperative ischemic lesions at declamping of the ECA and common carotid artery (CCA) while clamping the internal carotid artery (ICA). This study also aimed to determine whether intraoperative transcranial Doppler (TCD) monitoring predicts the risk for development of such lesions.