Carotid Arteriography Research Articles

Cost-effective evaluation and treatment for carotid disease.

To compare carotid endarterectomy (CEA) based solely on Duplex ultrasonography (DU) with CEA based on DU and arteriography. Retrospective case series analysis in a regional tertiary care center. Consecutive sample of 194 patients undergoing 218 CEAs from January 1, 1993, through June 30, 1995, with either preoperative DU plus arteriography (165 CEAs) or DU only (53 CEAs). Concordance of the 2 diagnostic imaging techniques and influence of these on the conduct of surgery, surgical outcome, and resource cost. There was agreement (kappa = 0.85) between DU and arteriography in the detection of a carotid occlusion or a stenosis greater than 45%. Arteriography demonstrated 26 aortic arch branch lesions (15.8%), 22 intracranial abnormalities (13.3%), and 6 type C ulcers (3.6%), in addition to 1 nonoccluded internal carotid artery (ICA) (0.61%) and 1 contralateral severe ICA stenosis (0.61%) inaccurately estimated by Duplex. These findings prompted 3 changes (1.8%) in surgical therapy, including 2 decisions in favor of CEA and 1 subclavian-carotid bypass added to CEA. There was no difference in the stroke and death rate for CEA based solely on DU compared with CEA based on DU and arteriography (P = .43). The mean total hospital cost was $5,534 for DU only CEA vs $7,608 for DU plus arteriogram CEA (mean difference = $2,074, P < .01). The addition of carotid arteriography to a diagnostic Duplex ultrasound study that already suggested the need for CEA did not change the operative plan in 98% (162/165) of the cases. Carotid endarterectomy based solely on DU is appropriate and cost-effective.

Cost-efficient carotid surgery: a comprehensive evaluation.

This study was performed to determine whether comprehensive cost-cutting strategies adversely affect the outcome in patients undergoing carotid endarterectomy. From December 1994 to December 1995, 237 consecutive patients undergoing 260 carotid endarterectomies were prospectively studied. The following variables were assessed: carotid arteriography, preoperative laboratory tests, electrocardiograms and chest x-ray films, use of carotid shunts during operation, use of pathology department, intensive care, oxygen therapy, telemetry, and hospital stay. In addition, complications were tabulated. Previously, all variables evaluated were routinely ordered. Subsequent to initiating the cost-containment strategies, the following results were achieved: arteriography in 52 (22%) of 237 patients, preoperative complete blood cell count and SMA-7 in 161 (62%) of 260 cases, preoperative electrocardiograms in 185 (71%) of 260 cases, preoperative chest x-ray films in 190 (73%) of 260 cases, carotid shunts in 83 (32%) of 260 cases, disease in no cases (0%), intensive care in 29 (11%) of 260 cases, oxygen therapy in 34 (13%) of 260 cases, telemetry in 17 (7%) of 260 cases, and hospital stay was decreased from an average of 2.6 to 1.3 days. Total savings based on average hospital and physician charges was $2.3 million. Complications included four strokes, one myocardial infarction, and no deaths. No patient required readmission. No recurrent or new neurologic or cardiac findings were identified clinically in follow-up at 1 and 4 weeks after surgery. The results clearly demonstrate that comprehensive cost-cutting strategies can reduce charges significantly while maintaining patient safety.

Carotid Endarterectomy for Symptomatic Carotid Artery Disease Demonstrated by Duplex Ultrasound With Minimal Arteriographic Findings

Ulcerated or irregular heterogeneous carotid plaque as seen by duplex ultrasound can cause hemispheric transient ischemic attacks (TIAs) and/or a cerebrovascular accident, even if only associated with nonsignificant carotid stenosis on arteriography. The purpose of this study was to review our experience in patients who underwent a carotid endarterectomy after medical treatment had failed, based on pathologic findings detected by carotid duplex ultrasound with minimal disease on arteriography. The medical records of 14 patients who underwent carotid endarterectomy for TIA symptoms related to ulcerated or irregular heterogeneous plaques were analyzed. All had had preoperative carotid duplex ultrasound, arteriography, and cardiac and neurologic workups to rule out other causes for their TIAs. Medical treatment had failed in all of them. There were 10 men and four women whose median age was 68 years. Carotid duplex ultrasound showed irregular heterogeneous carotid plaque in all patients associated with 20% to 50% stenosis in 12 and approximately 50% to 60% stenosis in two. All had normal to < 20% stenosis on arteriograms. The duplex ultrasound findings were all confirmed at operation. All had an uneventful postoperative course with relief of symptoms. Carotid duplex ultrasound is superior to carotid arteriography in detecting irregular or ulcerative heterogeneous plaque associated with nonsignificant stenosis. Carotid duplex ultrasound can be used to determine the desirability of carotid endarterectomy after failed medical treatment in patients with classical and persistent TIA symptoms despite normal or minimal disease on arteriograms. A successful endarterectomy appears to predict an asymptomatic postoperative course.

A critical analysis of cerebral computed tomography scanning before elective carotid endarterectomy and its correlation to carotid stenosis

Cerebral computed tomography (CT) scanning has been suggested to play a role in the management of patients before carotid endarterectomy (CEA). This prospective study analyzes the value of CT scanning before elective CEA and the correlation of CT findings to significant carotid stenosis. This study includes 131 consecutive patients considered for CEA during a 2-year period. All patients underwent carotid duplex ultrasonography, carotid arteriography, and CT scanning. Eighty patients (61%) had transient ischemic attacks or prior strokes, and 51 (39%) had nonhemispheric symptoms or were asymptomatic. The CT scan was abnormal in 36 (27%) patients; however, no brain tumors or abnormalities to affect clinical management were revealed. Ninety-two CEAs were performed on 87 patients. Twenty-nine (32%) in the operative group had abnormal CT scans, but these did not influence operative decisions. On the basis of this rate of 0% of patients with CT findings to change surgical management in 92 cases, a maximum true rate of occurrence of up to 5% could be detected with alpha equals 0.05 by sampling a population of this size. Four patients (4%) had postoperative cerebral vascular accidents, and all of these had normal preoperative scans. Patients with 50% or more carotid stenosis on arteriogram were significantly more likely to have abnormal CT scans than patients with less than 50% stenosis (20% versus 7%, p = 0.0034). As carotid stenosis became more significant, the frequency of abnormal CT scans increased (p < 0.01). The cost of CT scanning was $66,089.50 in this study. Significant carotid stenosis was associated with a higher frequency of abnormal CT scans; however, routine preoperative CT scanning was unnecessary before elective CEA.

The role of common carotid artery end-diastolic velocity in near total or total internal carotid artery occlusion

To evaluate the role of the end-diastolic velocity (EDV) in the common carotid artery (CCA) as a marker of internal carotid artery (ICA) occlusion. Validation of retrospective data in a prospective clinical study. The EDV in 94 patients with total ICA occlusion and in 24 patients with high grade (95-99%) unilateral ICA stenosis identified on extracranial carotid colour-flow Duplex imaging (CFDI) and arteriography was reviewed, and was retrospectively compared to the EDV of 176 normal individuals. Identification of patients with ICA occlusion was most accurate (99.3%) with an ipsilateral EDV > or = 12 cm/s and a DIFF > or = 10 cm/s (DIFF = contralateral EDV -- ipsilateral EDV). These values were then prospectively applied to all 886 patients (67 with high grade stenosis or occlusion) who underwent CFDI at our institution during 1994. The EDV > or = 12 had a 92% sensitivity, a 99.4% negative predictive value (NPV) and a 85% specificity in distinguishing between occluded and patent ICA's. In combination with a DIFF > or = 10 was 80.4% sensitive and 97.5% specific. The positive predictive value of the EDV > or = 12 in the distinction between 95-99% ICA stenosis and ICA occlusion was 78.3%, and that of the combination was 85.4%. The EDV was rarely zero and 10% of patients with normal or minimally diseased ICA's had an EDV > or = 12 and/or a DIFF > or = 10. The EDV < or = 12 cm/s is a sensitive marker of ICA occlusion with a high NPV and in combination with the DIFF > or = 10 cm/s, is specific. Nevertheless, EDV parameters are inaccurate in the distinction of 95-99% ICA stenosis from occlusion. Low EDV can be found in a number of patients with minor or no ICA disease, particularly in those with a stroke or silent cerebral infarct.

Stent-grafting for the Large Common Carotid Artery Aneurysm

Spontaneous large aneurysms of the common carotid artery (CCA) are rare. Treatment strategy has not yet been established. We treated a patient with a spontaneous large aneurysm of the CCA with a stent-graft. We hereby report the case of successful endovascular treatment and its angiographic and ultrasonographic outcome. Case A 64-year-old woman with a history of transient right-sided hemiparesis visited our outpatient clinic at November 20, 2003. In addition, she had suffered from the soft mass getting larger in the neck. Carotid ultrasonography showed a large aneurysm of the right CCA in her neck, and the large aneurysm was her palpable soft mass. Magnetic resonance angiography (MRA) and carotid arteriography displayed it clearly. However, no vascular lesions were found referable to transient right-sided hemiparesis. She had no history of serious neck or head traumas After showing some treatment options, she hoped to undergo endovascular treatment with a stent-graft at January 20, 2004. Pre-operative angiography showed the large right CCA aneurysm with 19 x11 x 6 mm in size and the diameter of the right CCA near the aneurysm was about 7 mm. Under local anesthesia, we introduced 10Fr long sheath type guiding catheter into the right femoral artery and navigated it proximal to the right CCA aneurysm. After systemic anticoagulation with heparin, we measured carefully the diameter of the aneurysm by IVUS (intra-vascular ultrasonography). Then, we navigated a microcatheter (RapidTransit, Cordis) inside the right CCA aneurysm through the left femoral artery for possible coil embolization. We successfully deployed a self-expandable stent-graft (PASSAGER 10 mm _ 40 mm, Boston Scientific) through the 10-Fr guiding sheath and dilated it sufficiently with an 8mm balloon catheter. Immediately after post dilatation, the stent-graft was expanded enough to contact the CCA wall, and the aneurysm disappeared on angiograms. Therefore, we didn't perform coil embolization. Post-procedure carotid arteriography showed no visualization of the aneurysm. Three-month and twelve-month carotid ultrasonography and arteriography demonstrated complete obliteration and no recurrence of the right CCA aneurysm.

Carotid-Cavernous Fistula Associated with an Intracranial Lesion Caused by Cortical Venous Reflux

Digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) findings in 20 patients with carotid-cavernous fistula (CCF; 3 direct CCFs and 17 indirect CCFs) were retrospectively reviewed to evaluate venous drainage patterns that may cause intracerebral haemorrhage or venous congestion of the brain parenchyma. We evaluated the relationship between cortical venous reflux and abnormal signal intensity of the brain parenchyma on MRI. Cortical venous reflux was identified on DSA in 12 of 20 patients (60.0%) into the superficial middle cerebral vein (SMCV; n=4), the uncal vein (n=2), the petrosal vein (n=2), the lateral mesencephalic vein (LMCV; n=1), the anterior pontomesencephalic vein (APMV; n=1), both the APMV and the petrosal vein (n=1) and both the uncal vein and the SMCV (n=1). Features of venous congestion, such as tortuous and engorged veins, focal staining and delayed appearance of the veins, were demonstrated along the region of cortical venous reflux in the venous phase of internal carotid or vertebral arteriography in six of 20 patients (30.0%). These findings were not observed in the eight CCF patients who did not demonstrate cortical venous reflux. MRI revealed abnormal signal intensity of the brain parenchyma along the region with cortical venous reflux in four of 20 indirect CCF patients (20%). Of these four patients, one presented with putaminal haemorrhage, while the other three presented with hyperintensity of the pons, the middle cerebellar peduncle or both on T2-weighted images, reflecting venous congestion. The venous drainage routes were obliterated except for cortical venous reflux in these four patients and the patients without abnormal signal intensity on MRI had other patent venous outlets in addition to cortical venous reflux. CCF is commonly associated with cortical venous reflux. The obliteration or stenosis of venous drainage routes causes a converging venous outflow that develops into cortical venous reflux and results in venous congestion of the brain parenchyma or intracerebral haemorrhage. Hyperintensity of brain parenchyma along the region of cortical venous reflux on T2-weighted images reflects venous congestion and is the crucial finding that indicates concentration of venous drainage into cortical venous reflux.

Epidemiology of carotid endarterectomy and cerebral arteriography in the United States.

Results of North American and European trials of carotid endarterectomy published in 1991 may have affected the frequency of the procedure in the United States. Therefore, data from a national survey of hospital discharges were examined to determine whether rates of carotid endarterectomy and arteriography increased after 1991 and whether race and sex variations in rates have persisted. Data from the National Hospital Discharge Survey were examined for the years 1980 through 1993. Estimated numbers of procedures performed in nonfederal US hospitals were used to compute rates per 100,000 population by year, age, race, and sex. In persons aged 65 years and over, the rate of carotid endarterectomy increased rapidly between 1980 and 1983 with a slight further increase through 1985. A marked fall in the rate occurred between 1985 and 1988, followed by a plateau and a sharp upturn in 1992. After 1985, there was a steady decline in the rate of cerebral arteriography procedures in hospital. No reliable data were available on outpatient cerebral arteriography. Throughout the period, whites had estimated rates of carotid endarterectomy procedures over four times higher than blacks. Whites also had higher rates of cerebral arteriography, but the disparity was not as great as for endarterectomy. Rates of carotid endarterectomy were 60% higher in men than women, but rates of cerebral arteriography were only 9% higher in men than women. Rates of carotid endarterectomy increased sharply after the 1991 publication of trial results. Marked racial disparities in the use of this procedure persist and require further evaluation.

Prevalence of asymptomatic carotid stenosis in patients undergoing infrainguinal bypass surgery.

The prevalence of asymptomatic carotid stenosis in patients with lower-extremity ischemia is unknown. This report represents the largest carotid screening program to date of patients undergoing leg bypass. Patients undergoing infrainguinal bypass from 1987 through 1993 on the vascular surgery service at Oregon Health Sciences University, Portland, underwent routine carotid duplex examinations to detect the presence of asymptomatic carotid stenosis. During the study period, 352 patients underwent infrainguinal revascularization for ischemia, of whom 225 (64%) had no prior carotid surgery, carotid arteriography, or cerebrovascular symptoms. There were 117 men and 108 women, with a mean age of 67 years. The indication for surgery was limb salvage in 67% and claudication in 33% of patients. Sixty-four patients (28.4%) who required lower-extremity revascularization had hemodynamically significant asymptomatic carotid artery stenosis or occlusion; 12.4% had stenosis of 60% or greater, the qualifying level for randomization in the Asymptomatic Carotid Atherosclerosis Study. Based on these findings, eight patients with carotid stenosis of 80% or greater underwent elective carotid endarterectomy. There were no postoperative neurologic events in the 225 leg bypass patients. By multivariate logistic regression analysis, the presence of carotid bruit (P < .001) and the presence of rest pain (P = .006) were associated with carotid stenosis of 50% or greater. Limiting screening to patients with carotid bruit, limb salvage indications for surgery, and/or advanced age excluded significant numbers of patients with stenosis; thus, these were not effective screening strategies. Screening carotid duplex scanning is indicated in patients who require lower-extremity revascularization.

Short-stay carotid endarterectomy is safe and cost-effective

Carotid endarterectomy (CEA) is conventionally performed following a contrast arteriogram, under general anesthesia, and with postoperative admission to an intensive care unit (ICU). We investigated whether any of these traditional adjuncts to CEA is necessary. Eighteen consecutive patients had CEA performed according to a protocol of duplex scanning only, operation under regional anesthesia, and admission to the ICU only in cases of a proven need for services unique to the ICU (group I). Utilization of preoperative arteriography, admission to the ICU, postoperative complications, total hospital length of stay, and hospital charges were calculated for this group and results were compared with a group of 178 patients undergoing conventional CEA (arteriography, general anesthesia, routine ICU admission) during the same period (group II). In group I, 1 patient (6%) underwent preoperative arteriography and 4 patients (22%) were admitted to the ICU after CEA. Most group II patients (114 of 178, or 64%) underwent preoperative arteriography and virtually all (175 of 178, or 98%) were admitted to the ICU. Compared with group II, the average hospital length of stay for group I was significantly shorter (1.3 +/- 0.1 versus 3.1 +/- 0.3 days, P = 0.03) and hospital charges were significantly reduced ($5,861 +/- 229 versus $11,140 +/- 729, P = 0.02). This pilot study suggests that CEA can be safely performed without routine preoperative carotid arteriography; that routine ICU admission is unnecessary for the majority of cases; and that elimination of routine arteriography and ICU admission can reduce hospital charges for CEA by nearly one half.

Cross-filling of circle of willis and carotid stenosis by angiography, duplex ultrasound, and oculopneumoplethysmography

To evaluate the filling of the Circle of Willis on preoperative arteriograms and to correlate this observation with the results of oculopneumoplethysmography (OPG) and severity of carotid stenosis as determined by duplex ultrasonography and angiography. Ninety-five patients underwent OPG, duplex ultrasonography, and selective carotid and vertebral arteriography. In all, 45 (88%) patients with a positive OPG had interhemispheric cross-filling of the middle cerebral artery and anterior cerebral artery from a contralateral carotid injection in contrast with 10 (23%) patients with a negative OPG (P < 0.001). Of patients with carotid stenosis > or = 80% on duplex ultrasound, 39 (91%) had cross-filling from a contralateral carotid injection in contrast with 16 (31%) patients with < 80% stenosis (P < 0.001). Of patients with carotid stenosis > or = 80% on arteriogram, 37 (90%) had cross-filling from a contralateral carotid injection in contrast with 18 (33%) patients with < 80% stenosis (P < 0.001). These data suggest that the Circle of Willis is frequently incompetent as a collateral pathway and that arteriographic cross-filling is not a reliable index of this pathway. Patients with a positive OPG and corresponding carotid stenosis are likely to have a physiologically incompetent collateral pathway. Perhaps these patients should undergo surgery, even if the stenosis is less than 80%.

The diagnostic accuracy of duplex ultrasonography for evaluating carotid bifurcation

In many medical centers the standard preoperative study for patients undergoing carotid endarterectomy is four-vessel carotid arteriography, but duplex scanning of the carotid bifurcation is also reported to be highly accurate for detecting stenotic or occluded carotid arteries. The diagnostic accuracy of duplex ultrasonography was evaluated in a study of 774 carotid bifurcations, in 400 patients comparing the degree of predicted internal carotid artery (ICA) stenosis found using that technique, with that found by contrast arteriography. Agreement between the predicted degree of ICA stenosis and the arteriographic measurement was evaluated using the Spearman rank order correlation. Accuracy statistics for duplex scanning as a diagnostic modality were assessed using 2 x 2 tables. The Spearman rank order correlation coefficient was 0.74 (P = 0) for the symptomatic group, 0.65 (P = 0) for the asymptomatic group, and 0.68 (P = 0) for the total group. The accuracy of duplex ultrasonography for detecting all grades of ICA stenosis ranged from 80% to 97%. Duplex ultrasonography of the carotid bifurcation is a reliable diagnostic tool and can be used as the sole preoperative study for selected patients with extracranial cerebrovascular disease. Our current algorithm is discussed in conjunction with a critical analysis of this large database.

Watershed Ischemia Demonstrated With Acetazolamide Enhanced Tc-99m HMPAO SPECT

A 75-year-old man who had a small right parietal infarction 8 months earlier underwent baseline and acetazolamide enhanced Tc-99m hexamethylpropylene amineoxime brain SPECT imaging. The acetazolamide study demonstrated a bilaterally symmetric perfusion deficit posteriorly near the midline. The baseline study was essentially normal. This finding was felt to represent watershed ischemia at the junction of the anterior circulations (anterior cerebral and middle cerebral arteries) and the posterior circulation (posterior cerebral artery). Carotid arteriography subsequently demonstrated left subclavian steal syndrome with retrograde flow through the left vertebral artery.

Petrous Apex Lesions

The purpose of this article is to detail our experience in treating 69 patients over the past 6 years with pathologic processes involving the petrous apex. These included 25 (36%) primary petrous apex lesions, 40 (58%) lesions that involved the petrous apex by direct invasion from an adjacent region, and four (6%) lesions that were the result of metastatic spread from a distant site. Although lesions of the petrous apex are uncommon, they may present significant morbidity to the patient. The symptoms elicited by these lesions are usually vague and nonlocalizing in the early stages but may progress to include multiple cranial neuropathies. Successful results are contingent on early diagnosis, which requires a high index of suspicion and use of appropriate imaging modalities. Thorough preoperative assessment with use of computed tomography, magnetic resonance imaging, and carotid arteriography is essential to plan the surgical approach. We present this collection of patients in order to aid in the further preoperative characterization of the differences in primary and secondary lesions of the petrous apex.

The temperature within the circle of Willis versus tympanic temperature in resting normothermic humans

We measured the temperature of arterial blood within the circle of Willis (T(Willis)) in seven normothermic patients undergoing carotid arteriography. We found this temperature to be lower by 0.13 to 0.30 degrees C than tympanic temperature and by 0.30 to 0.55 degrees C lower than rectal temperature. By imposing this data on calculated cerebral heat balance it can be suggested that the average cerebral temperature of a resting subject is somewhat higher than tympanic temperature. These findings would also support indirectly the thesis that temperature gradients may exist within the brain.

Noninvasive Carotid Duplex Ultrasound Imaging for the Evaluation and Management of Carotid Atherosclerotic Disease

Renewed interest in surgical management of atherosclerotic disease of the carotid bifurcation underscores the necessity for accurate and efficacious means for diagnostic evaluation of patients with suspected carotid disease. Noninvasive testing by carotid duplex ultrasound, which combines high-resolution B-mode imaging with pulsed Doppler spectral analysis, is the method of choice. Noninvasive testing permits identification of potentially significant carotid stenosis, occlusion, or unstable plaque morphology with virtually no significant morbidity from the testing itself. Symptomatic patients, or patients with asymptomatic carotid bruits, can be evaluated serially to determine disease progression or response to medical management. In patients who are surgical candidates, substitution of noninvasive duplex ultrasound evaluation for carotid arteriography is controversial. Noninvasive testing is highly technique-dependent and probably requires at least 1 year of experience for acquisition of a sufficient "learning curve" for diagnostic reliability. This applies not only to the technical performance of the test but to interpretation of results. Proper training of technicians and quality assurance in individual vascular laboratories are crucial elements with respect to accuracy and reliability of results obtained in noninvasive testing.

Modalities of compensation of cerebral circulation through the circle of Willis in stenoses and occlusions of extracranial arteries.

We have studied the intracranial cerebral circulation in 6 patients with bilateral ischaemic lesions of the internal carotid artery in the extracranial segment (2 significant bilateral stenosis cases; 1 case with bilateral thrombosis and 3 cases of unilateral thrombosis and significant contralateral stenosis). All the patients were males, their age being between the 5th and 8th decade. In a single case the neurological examination showed secondary left hemiplegia and recent right paresis of remittent type, while the other 5 patients had only transitory ischaemic attacks with hemiparesis or transitory aphasia. The lesions were revealed by means of duplex system echotomography (Aloka-Hellige Model SSD 630) and spectral analysis of Doppler signal (Vasoscan-Sonicaid) and they were confirmed later by bilateral carotid arteriography in all patients. The intracranial circulation was also followed up by non-invasive methods, making use of spectral-analysis of the Doppler signal with pulsed wave on TC-2 64-B apparatus. The cases studied by us, which present pathogenic situations more rarely encountered, have shown that none of them observed a 'mathematical model' of compensation of blood flow (BF). More exactly, 2 patients with the same type of lesions and topography did not have a unique model of compensation of BF. It seems that both the possibilities of individual self-regulation of cerebral BF and the extracerebral factors, especially those belonging to cardiac activity, are decisive in the compensatory activity of cerebral circulation, while the modalities in which this is accomplished depend chiefly upon the functional condition of the collateral arteries as a whole.

Is routine CT scanning necessary in the preoperative evaluation of patients undergoing carotid endarterectomy?

To evaluate the usefulness of CT scanning before carotid endarterectomy, a prospective study was performed on 469 consecutive patients considered for carotid endarterectomy during a 5-year period. All patients underwent carotid duplex scanning and CT scanning before carotid arteriography. Two hundred thirty-seven patients (51%) had transient ischemic attacks, 109 (23%) had a prior stroke, and 122 (26%) were asymptomatic. Results of the CT scan were abnormal in 68 (62%) of the 109 patients with stroke. Fifty-one of the 360 patients (14%) without a clinical history of stroke had an abnormal CT scan outcome. Of patients with a stroke documented by CT scanning, 27 had lacunar infarcts, and 92 had cortical infarcts; these findings did not change surgical management in any patient. CT scanning did not reveal any unsuspected infarcts or tumors. Two hundred thirty carotid endarterectomies were performed on 206 patients. Forty-seven patients (23%) in the operative group had abnormal CT scan findings, but the scan did not influence operative decisions or timing in any case. Seventy-two patients (27%) in the nonoperative group had abnormal CT scan results, but CT scan findings did not exclude any patient from arteriography or surgery. Three perioperative strokes (1.3%) occurred. CT scan findings did not correlate with postoperative neurologic complications. Cost of CT scanning was one-half million dollars in our study alone. Routine CT scanning is unnecessary before carotid endarterectomy and is not cost-effective.

Hemangioma of the nasal vault: MR and CT features.

Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition.

Predictors of Intracranial Carotid Artery Atherosclerosis

The effect of cigarette smoking on intracranial internal carotid artery atherosclerosis (ICAS) was studied by obtaining cigarette smoking histories and data on other potential predictors, including serum lipid estimations, for consecutive patients undergoing carotid arteriography. The duration of cigarette smoking was the most significant independent predictor of the presence of ICAS. Other independently significant predictors of ICAS were hypertension, diabetes mellitus, and current systolic blood pressure. The interaction of diabetes and duration of smoking was a significant negative predictor. In patients for whom serum lipid values were available, lower levels of apolipoprotein A-I were associated with a higher risk of having ICAS. However, the effect of apolipoprotein A-I as a predictor of the presence of ICAS was far outweighted by the effects of duration of smoking and hypertension.