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Objectives: The goal of this study was to compare the risk of stroke between patients with carotid artery disease with and without the presence of intraplaque hemorrhage (IPH) on magnetic resonance imaging., Background: IPH in carotid stenosis increases the risk of cerebrovascular events. Uncertainty remains whether risk of stroke alone is increased and whether stroke is predicted independently of known risk factors., Methods: Data were pooled from 7 cohort studies including 560 patients with symptomatic carotid stenosis and 136 patients with asymptomatic carotid stenosis. Hazards of ipsilateral ischemic stroke (primary outcome) were compared between patients with and without IPH, adjusted for clinical risk factors., Results: IPH was present in 51.6% of patients with symptomatic carotid stenosis and 29.4% of patients with asymptomatic carotid stenosis. During 1,121 observed person-years, 66 ipsilateral strokes occurred. Presence of IPH at baseline increased the risk of ipsilateral stroke both in symptomatic (hazard ratio [HR]: 10.2; 95% confidence interval [CI]: 4.6 to 22.5) and asymptomatic (HR: 7.9; 95% CI: 1.3 to 47.6) patients. Among patients with symptomatic carotid stenosis, annualized event rates of ipsilateral stroke in those with IPH versus those without IPH were 9.0% versus 0.7% (<50% stenosis), 18.1% versus 2.1% (50% to 69% stenosis), and 29.3% versus 1.5% (70% to 99% stenosis). Annualized event rates among patients with asymptomatic carotid stenosis were 5.4% in those with IPH versus 0.8% in those without IPH. Multivariate analysis identified IPH (HR: 11.0; 95% CI: 4.8 to 25.1) and severe degree of stenosis (HR: 3.3; 95% CI: 1.4 to 7.8) as independent predictors of ipsilateral stroke., Conclusions: IPH is common in patients with symptomatic and asymptomatic carotid stenosis and is a stronger predictor of stroke than any known clinical risk factors. Magnetic resonance imaging might help identify patients with carotid disease who would benefit from revascularization., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Most carotid near-occlusions are indistinguishable from conventional ≥ 50% stenosis on ultrasound, demonstrating high peak systolic velocity (PSV) in the stenosis., Purpose: To study whether the velocity distal to the stenosis can separate high PSV near-occlusion from conventional ≥ 50% stenosis., Material and Methods: We included patients with ≥ 50% carotid stenosis with high PSV (≥125 cm/s), examined with both computed tomography angiography (CTA) and ultrasound within 30 days, and a distal velocity measurement was performed. Based on CTA, cases were divided into three groups: conventional stenosis; near-occlusion without full collapse (NwoC; normal-appearing albeit small distal artery); and near-occlusion with full collapse (NwC; threadlike distal artery). Distal Doppler ultrasound flow velocities were compared between these groups., Results: Sixty patients were included: 33 patients with conventional stenosis; 20 patients with NwoC; and seven patients with NwC. Mean distal PSV was 93, 63, and 21 cm/s ( P < 0.001) and mean distal end-diastolic velocity was 30, 24, and 5 cm/s ( P < 0.001), respectively. A distal PSV < 50 cm/s was 63% sensitive and 94% specific for separating both types of near-occlusion from conventional stenosis., Conclusion: In high PSV carotid stenoses, the distal velocity was lower in near-occlusions than conventional carotid stenosis. Distal velocities warrant further investigation in diagnostic studies.

Purpose: Carotid near-occlusion is a tight atherosclerotic stenosis of the internal carotid artery (ICA) resulting in decrease in diameter of the vessel lumen distal to the stenosis. Near-occlusions can be classified as with or without full collapse, and may have high peak systolic velocity (PSV) across the stenosis, mimicking conventional > 50% carotid artery stenosis. We aimed to determine how frequently near-occlusions have high PSV in the stenosis and determine how accurately carotid Doppler ultrasound can distinguish high-velocity near-occlusion from conventional stenosis., Methods: Included patients had near-occlusion or conventional stenosis with carotid ultrasound and CT angiogram (CTA) performed within 30 days of each other. CTA examinations were analyzed by two blinded expert readers. Velocities in the internal and common carotid arteries were recorded. Mean velocity, pulsatility index, and ratios were calculated, giving 12 Doppler parameters for analysis., Results: Of 136 patients, 82 had conventional stenosis and 54 had near-occlusion on CTA. Of near-occlusions, 40 (74%) had high PSV (≥ 125 cm/s) across the stenosis. Ten Doppler parameters significantly differed between conventional stenosis and high-velocity near-occlusion groups. However, no parameter was highly sensitive and specific to separate the groups., Conclusion: Near-occlusions frequently have high PSV across the stenosis, particularly those without full collapse. Carotid Doppler ultrasound does not seem able to distinguish conventional stenosis from high-velocity near-occlusion. These findings question the use of ultrasound alone for preoperative imaging evaluation.

Background and Purpose: Calcium can potentially shorten T1, generating high signal intensity in GREs. Because IPH appears as high signal intensity in MRIPH and the surface effects of calcium can potentially shorten T1 of surrounding water protons, the purpose of this study was to evaluate whether the high signal intensity seen on MRIPH could be attributed solely to IPH and not calcification., Materials and Methods: Eleven patients undergoing carotid endarterectomy were imaged by using MRIPH. Calcification was assessed by scanning respective endarterectomy specimens with a tabletop MicroCT. MRIPH/MicroCT correlation used an 8-segment template. Two readers evaluated images from both modalities. Agreement between MRIPH/MicroCT was measured by calculating Cohen κ., Results: High signal intensity was seen in 58.8% and 68.9% (readers 1 and 2, respectively) of MRIPH segments, whereas calcification was seen in 44.7% and 32.1% (readers 1 and 2, respectively) of MicroCT segments. High signal intensity seen by MRIPH showed very good but inverse agreement to calcification (κ = -0.90; P < .0001, 95% CI, -0.93 to -0.86, reader 1; and κ = -0.74; P < .0001; 95% CI, -0.81 to -0.69, reader 2). Most interesting, high signal intensity demonstrated excellent agreement with lack of calcification on MicroCT (κ = 0.92; P < .0001; 95% CI, 0.89-0.94, reader 1; and κ = 0.97; P < .0001; 95% CI, 0.96-0.99, reader 2). In a very small number of segments, high signal intensity was seen in MRIPH, and calcification was seen on MicroCT; however, these represented a very small proportion of segments with high signal intensity (5.9% and 1.6%, readers 1 and 2, respectively)., Conclusions: High signal intensity, therefore, reliably identified IPH, known to describe complicated plaque, rather than calcification, which is increasingly recognized as identifying more stable vascular disease.

Purpose: To investigate the association between magnetic resonance (MR) imaging-depicted intraplaque hemorrhage (IPH) in the carotid artery wall and the risk of future ipsilateral cerebrovascular events in men with asymptomatic moderate carotid stenosis by using a rapid three-dimensional T1-weighted fat-suppressed spoiled gradient-echo sequence., Materials and Methods: The institutional ethics review board approved this retrospective chart review and waived the requirement for written informed consent. All patients gave informed verbal consent at follow-up telephone interviews. Ninety-one men (mean age, 74.8 years; range, 47-88 years) who attended a vascular clinic between 2003 and 2006, who had asymptomatic carotid stenosis (50%-70% at Doppler ultrasonography), and who had undergone MR imaging for IPH detection were retrospectively identified. Seventy-five men with 98 eligible carotid arteries were included in the study. Patients were followed for a minimum of 1 year (mean follow-up, 24.92 months; range, 12-43 months). Kaplan-Meier survival and univariate Cox regression analyses were conducted to compare future ipsilateral cerebrovascular event rates between carotid arteries with and those without MR-depicted IPH., Results: Of the 98 carotid arteries included, 36 (36.7%) had MR-depicted IPH. Six cerebrovascular events (two strokes and four transient ischemic attacks) occurred in the carotid arteries with IPH, as compared with no clinical events in the carotid arteries without IPH. Univariate Cox regression analysis confirmed that MR-depicted IPH was associated with an increased risk of cerebrovascular events (hazard ratio, 3.59; 95% confidence interval: 2.48, 4.71; P < .001). MR-depicted IPH negatively predicted outcomes (negative predictive value = 100%)., Conclusion: In this cohort with asymptomatic moderate carotid stenosis, MR-depicted IPH was associated with future ipsilateral cerebrovascular events. Conversely, patients without MR-depicted IPH remained asymptomatic during follow-up. The absence of IPH at MR imaging, therefore, may be a reassuring marker of plaque stability and of a lower risk of thromboembolism.

Objectives: To study the risk factors and rate of progression of asymptomatic carotid stenosis in patients with peripheral arterial occlusive disease., Methods: Between July 1999 and September 2003, we studied consecutive patients referred to a vascular laboratory for peripheral arterial occlusive disease who had not experienced neurologic symptoms within the previous 3 years. Carotid duplex ultrasound scan (DUS) was performed at baseline and at 6 to 12-month intervals. The internal carotid artery peak systolic velocity (PSV) was used to determine severity of carotid stenosis. Multilevel linear regression modeling (MLM) was used to identify the rate of progression and risk factors for progression., Results: For 614 consecutive patients, median follow-up by DUS was 30 (2-42) months. Patients were 73 +/- 10-years-old, and 62% were men. Mean ankle-brachial index (ABI) was 0.79 +/- 0.24. The baseline prevalence of carotid stenosis >or=50% (PSV >or=125 cm/second) was 22%. During follow-up, ipsilateral amaurosis fugax, transient ischemic attacks, and strokes occurred in 3 (0.4%), 7 (1.1%), and 5 (0.8%) patients, respectively. Overall, there was little progression in carotid stenosis. Female gender, low ABI, and smoking were risk factors for progression of disease regardless of severity of carotid stenosis. Patients with >or=50% carotid stenosis were at greatest risk of progression if they continued smoking and were diabetic. Prediction models for progression of carotid stenosis given a baseline PSV and patient risk factors were constructed., Conclusion: There are few neurologic events in patients with asymptomatic carotid stenosis. The average rate of progression of stenosis over 2 years is not significant but greater in diabetic patients with baseline stenosis >50% who continue smoking. Rescreening by serial DUS should be limited to high-grade stenosis and follow-up performed at an interval of 1-2 years.

Objectives: The objective is to report the feasibility and technique of treating popliteal artery aneurysms (PAA) with a stent made of nitinol rings externally supported by thin polyester (Anaconda limbs)., Background: PAA are the most common peripheral aneurysms. The main limitations of stents used in these settings are: short lengths, longitudinal and horizontal compliance mismatch; graft failure from angulation and movement at the joint level; and dislodgment., Methods: This is a prospective multicenter cohort study of consecutive symptomatic and asymptomatic PAA treated in tertiary vascular centers. Outcomes included patency of the stent and postoperative time-to-independent-ambulation and to-climb-a-flight-of-stairs., Results: Fourteen PAA were treated in 12 men, age 72 +/- 3 years. The median ASA classification was 2.5. The length of artery covered was 147 +/- 41 mm. The PAA diameter was 31 +/- 5 mm, 6 were symptomatic. One stent was used in 6 aneurysms, two in 7, and three in 1. The average stent diameter was 10 +/- 1 mm. The length of the proximal neck was 24 +/- 6 mm with a diameter of 9.8 +/- 1.9, and length of the distal neck 23 +/- 3 mm with a diameter of 8.7 +/- 1.2 mm. In 6 aneurysms, the stent crossed the knee joint. There was no mortality, and one stent occluded (primary patency 93% at 6 +/- 3 months). The median hospital stay was 1.7 days, time to independent ambulation was 3 hr and the time to climbing a flight of stairs was 1 day., Conclusions: The use of Anaconda limbs for endovascular repair of PAA is feasible and safe., ((c) 2008 Wiley-Liss, Inc.)

Purpose: To apply magnetic resonance (MR) imaging of intraplaque hemorrhage (IPH), as compared with histologic analysis as the reference standard, to detect T1 hyperintense intraplaque signal and to test the hypothesis that T1 hyperintense material represents blood products (methemoglobin)., Materials and Methods: Institutional review board approval and patient informed consent were obtained. Eleven patients undergoing carotid endarterectomy were examined with MR imaging of IPH, and MR images were assessed for T1 hyperintense intraplaque signal. A total of 160 images per patient were available for coregistration with corresponding histologic slices. Because of endarterectomy specimen size and degradation and processing artifacts, only 97 images were coregistered to corresponding histologic slices. A grid that consisted of 16 segments was overlaid on images for correlation of MR images and histologic slices. Only one of 16 segments was chosen randomly per slide and used in the analysis. Agreement between MR images and histologic slices was measured with the Cohen kappa statistic., Results: Strong agreement was seen between MR images and histologic slices, with T1-weighted high signal intensity corresponding to hemorrhagic material (kappa = 0.7-0.8). There was a low 2% false-negative rate for the detection of hemorrhage on the basis of T1-weighted hyperintensity (two of 97 measured segments). The results of diagnostic tests for T1 hyperintense detection of hemorrhage were as follows: sensitivity of 100%, specificity of 80%, positive predictive value of 70%, and negative predictive value of 100% for reader 1 and sensitivity of 94%, specificity of 88%, positive predictive value of 78%, and negative predictive value of 97% for reader 2., Conclusion: With its high spatial resolution, MR imaging of IPH permits detection of plaque hemorrhage location, resulting in strong agreement between imaging and histologic findings., ((c) RSNA, 2008.)

Background: Blunt vena caval injury (BCI) is uncommon with only a few published reports in the literature. Recently, with high resolution computed tomography (CT) scan imaging signs of caval injury are sometimes found in hemodynamically stable patients. The purpose of this study was to assess the current course of patients with BCI., Methods: Retrospective review of all patients with BCI treated at a Regional Trauma Center from April 1999 to May 2005. Data collected included demographics, mechanism of injury, associated injuries, diagnostic investigations, surgical findings, and outcomes., Results: During the 6-year study period, 10 patients presented with BCI (age 42 +/- 19 years; 70% mortality; Injury Severity Score 39 +/- 15). The spectrum of vena cava injury ranged from an intimal flap to extensive destruction. Six of the seven deaths were secondary to exsanguination and one secondary to severe brain injury. Four patients presented with refractory shock and were taken emergently to surgery (all died). Six patients responded to fluid resuscitation and underwent CT imaging (three out of six survived). Although active venous contrast extravasation was not seen in any patient, all six had indirect signs on CT suggestive of BCI. Overall, the diagnosis of BCI was confirmed at surgery in nine patients. The remaining patient had an intimal flap and contained pericaval hematoma confirmed by ultrasound, and was successfully managed nonoperatively., Conclusions: The spectrum of BCI ranges from intimal flaps to extensive destruction. CT imaging may not diagnose or may underestimate the severity of BCI. Stable patients with intimal flaps and contained hematoma may be successfully managed nonoperatively.

Objective: The objective of this article was to assess the feasibility of MR direct thrombus imaging (MRDTI) to evaluate the prevalence and location of complicated upper thoracic aortic and arch vessel plaque in patients referred for evaluation of cerebrovascular disease., Subjects and Methods: Patients referred for investigation of cerebrovascular disease by MRI were enrolled. Reasons for referral included transient ischemic attack/amaurosis fugax, acute infarct, remote infarct, or asymptomatic carotid disease. Of the 348 patients initially scanned, 17 were excluded from the analysis. The final patient population included 331 patients (199 men, 132 women; mean age, 67.7 years). Patients were scanned using MRDTI, a 3D, T1-weighted, fat-suppressed spoiled gradient echo that exploits the T1 shortening effects of methemoglobin, directly visualizing hemorrhage/thrombus in the vessel wall, thus identifying complicated plaque. Complicated plaque was defined as a high signal within the atherosclerotic plaque at least twice the signal intensity of muscle., Results: Forty-three of 331 patients (13%) had complicated upper thoracic aortic atherosclerotic disease, arch vessel atherosclerotic disease, or both. The upper thoracic aorta was involved in 36 of 43 patients (83.7%), and the left subclavian artery was involved in 14 of 43 patients (32.6%). Both the right subclavian artery and the brachiocephalic artery were involved in one of 43 patients (2.3%). Complicated carotid plaque was seen in 25 of 43 patients (58.1%)., Conclusion: MRDTI can be applied in the detection of complicated plaque in the upper thoracic aorta and arch vessels. Complicated plaque was identified in 13% of the patient population. The upper thoracic aorta was the most common site involved. This technique could be useful for the screening of asymptomatic at-risk patients.

Objective: The purpose of this study was to determine the prevalence of significant carotid stenosis, to identify risk factors increasing this prevalence, and to determine the risk of progression of stenosis, in patients with peripheral arterial occlusive disease who are neurologically asymptomatic., Study Design: Consecutive patients who underwent evaluation in a vascular laboratory for peripheral arterial occlusive disease, who had no recent neurologic symptoms, were investigated., Results: From July 1999 to December 2000, 620 patients underwent duplex scanning on one occasion, and 417 on two occasions. The average age was 72 +/- 10 years, and 61% were men. An occluded internal carotid artery was found in 4.8% of patients. The prevalence of a carotid stenosis >50% was 33% on the initial evaluation. Age of more than 70 years (P =.007), diabetes mellitus (P =.042), history of stroke (P =.011), and ankle/brachial index of less than 0.8 (P =.0006), were independently associated with carotid stenosis >50%. The odds ratio associated with each of these risk factors was similar. The prevalence of carotid stenosis >50% was 16%, 21%, 38%, 47%, and 44% for patients with no, one, two, three, and four risk factors, respectively. The highest prevalence of carotid stenosis >50% was identified in patients with ankle/brachial indices of less than 0.4 (59%). During the follow-up period, no patient had a cerebrovascular event. In 15% of carotid arteries, progression from one class of stenosis to a more severe class was observed, and 6.5% of patients progressed from a lower degree to 50% to 99% stenosis. No differences in progression of disease were identified when the variables of age, diabetes, previous stroke, and ankle/brachial index of less than 0.8 were studied or when patients with zero to two of these putative risk factors were compared with patients with three or four., Conclusion: Screening for carotid stenosis in asymptomatic patients with peripheral vascular disease is justifiable, but not mandatory, when two or more risk factors are present or when the ankle/brachial index is less than 0.4. Rates of progression to clinically significant stenosis are low and do not justify reevaluation every 6 months. Further research to identify the optimal interval for reevaluation is needed.

Background and Purpose: During our annual audits of carotid endarterectomy (CEA) in Toronto metropolitan hospitals, we have been aware of major changes in the practice of this operation in recent years. To evaluate the effect of changing practice on costs of carotid endarterectomy, we have therefore compared the effects of changes in length of stay, complication rates, and other variables on cost during the last 3 years for which we have complete data., Methods: We evaluated 757 consecutive patients, of whom 600 had CEA procedures in 3 teaching hospitals, and 190 procedures in 2 community hospitals in metropolitan Toronto. We estimated costs using a specially designed computer program, Transitional System Incorporated, including surgical complications, in patients admitted between January 1994 and December 1996., Results: There was a significant decrease in length of stay in both groups of hospitals, mainly due to preoperative outpatient evaluation but also due to lower complication rates, which probably reflect an increase in asymptomatic surgery in both hospital groups. Costs fell from approximately $8000 per procedure to $5000 in asymptomatic patients and from approximately $10,000 to $7000 in symptomatic patients (Can $)., Conclusions: Major changes in the management of patients undergoing CEA have resulted in a significant decrease in both length of hospital stay and utilization of postoperative intensive care. At the same time, complication rates have significantly fallen, although our mortality and morbidity figures remain slightly higher than those from published multicenter trials. Future changes in surgical practice in Canada, including noninvasive carotid imaging, should produce even lower costs within the next few years.

Objective: To assess long-term outcomes in multisystem trauma victims who have arterial injuries to upper limbs., Design: A retrospective case series., Setting: Tertiary care regional trauma centre in a university hospital., Patients: All consecutive severely injured patients (Injury Severity Score greater than 15) with an upper limb arterial injury treated between January 1986 and January 1995. Demographic data and the nature and management of the arterial and associated injuries were determined from the trauma registry and the hospital records., Outcome Measures: Death rate, discharge disposition, residual disabilities and functional outcomes as measured by the Glasgow Outcome Scale., Results: Twenty-five (0.6%) of 4538 trauma patients assessed during the study period suffered upper extremity arterial injuries. Nineteen of them were victims of blunt trauma. The death rate was 24%. There were 10 primary and no secondary amputations. An autogenous vein interposition graft was placed in 10 patients. Concomitant fractures or nerve injuries in the upper limb were present in 80% and 86% of the patients, respectively. Long-term follow-up data (mean 2 years) were obtained in 16 of the 19 who survived to hospital discharge. The residual disability rate was high. It included upper limb joint contractures, pain and persistent neural deficits (69%). Associated injuries in other body areas also contributed to overall disability. Only 21% of the patients recovered completely or had only minor disabilities., Conclusions: Associated injuries, rather than the vascular injury, cause long-term disability in the multisystem trauma victim who has upper extremity involvement. Persistent neural deficits, joint contractures and pain are the principal reasons for long-term impairment of function.

Background: The North American (NASCET) and European (ECST) carotid surgery trials have shown a surgical benefit for symptomatic stenosis greater than 70%. The Asymptomatic Carotid Artery Surgery (ACAS) trial have shown some benefit for the stenosis greater than 60%. Although the NASCET/ACAS angiographic methods were similar, these are discrepant from ECST and have technical limitations inherent to measurement of the distal internal carotid artery (ICA) or guessing the ICA bulb diameter., Methods: Consecutive carotid angiograms were analyzed to verify the relationships between proximal and distal aspects of the common carotid artery (CCA) and ICA bulb. We then compared the NASCET and ECST methods and, two new techniques, the Common Carotid (CC) and Carotid Stenosis Index (CSI). The CC method is based on a direct comparison of the residual lumen to the distal CCA diameter adjacent to the bulb. The CSI is based on the known relationship between the proximal CCA and ICA (1.2 x CCA diameter = proximal CCA diameter). The normal ICA bulb diameter can therefore be calculated from direct measurement of the CCA., Results: 125 consecutive carotid angiograms were evaluated (250 arteries). Technical applicability of NASCET was 89%, ECST 95%, CC/CSI 99%. The CCA/ICA diameter ratios were established: 1.23 +/- 0.23 (ICA bulb/distal CCA), and 1.27 +/- 0.2 (ICA bulb/proximal CCA). The CCA is enlarged at its distal end that such the distal CCA/proximal CCA ratio is 1.04 +/- 0.12. The CC and CSI methods were statistically different in 8 of 10 groups when these methods were compared per decile stenosis (p < 0.04). However, CC and CSI methods disagreed in classifying patients into mild (0-29%), moderate (30-69%), and severe (70-99%) only in 3%, 5%, and 8% of cases. Linear regression analysis shows excellent correlation between the methods (CC = 15.7 + 0.82 x CSI, r2 = 0.92). Lumen asymmetry is most common with mild-to-moderate stenoses which may affect accuracy and reproducibility of measurements., Conclusions: We have confirmed previous data on the relationships between the components of the carotid artery. Of the different angiographic techniques, CSI is the most reliable validated method of measuring carotid stenosis, and is proposed as a bridge between results of carotid surgery trials, and to validate noninvasive modalities against angiography.

Purpose: The goal of the study was to assess the prevalence and severity of symptomatic and asymptomatic carotid artery disease in patients with peripheral vascular disease (PVD)., Methods: Consecutive patients with clinically and Doppler scanning-proven PVD (category 1 or greater) underwent prospective screening for the presence of carotid atherosclerosis with color-coded duplex ultrasonography. Preexisting risk factors were recorded with a standard questionnaire and included sex, age, diabetes mellitus, history of smoking, hypertension, prior stroke/transient ischemic attacks, and coronary artery disease., Results: Three hundred seventy-three consecutive patients were studied over 2 years. The mean age of the patients was 70 +/- 10 years; there were 223 (60%) men and 150 (40%) women; 71% of the patients had a history of smoking, 47% had coronary artery disease, 43% had hypertension, and 21% had diabetes mellitus. Two hundred eleven (57%) patients had 30% or greater carotid artery stenosis detected by carotid artery duplex scanning. Sixty-seven (32%) of these had symptoms of ischemic cerebral events, of whom 22 had potentially operable carotid artery stenoses (70% to 99%), whereas 72 of the 144 symptom-free patients had 60% to 99% stenosis. An additional 34 patients would be eligible candidates for the ongoing carotid endarterectomy trials (North American Symptomatic Carotid Endarterectomy Trial and European Carotid Surgery Trial). Although all the risk factors were associated significantly with PVD and carotid artery disease (p < 0.002), male sex and prior stroke/transient ischemic attack were the strongest predictors., Conclusions: Routine carotid ultrasound screening of 373 consecutive patients with category I or greater PVD revealed that 22 patients with symptoms and 72 symptom-free patients were potential surgical candidates, representing 25% of the study cohort. An additional 34 patients were potential candidates for enrollment into the North American Symptomatic Carotid Endarterectomy Trial and European Carotid Surgery Trial.

Background and Purpose: Current methods of measuring carotid stenosis such as those used in the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST) have limitations caused by difficulties in measuring the normal width of the distal internal carotid artery (ICA) or the carotid bulb., Methods: We developed a new technique, the Carotid Stenosis Index (CSI), based on the known anatomic relationship between the common carotid artery (CCA) and ICA (1.2 x CCA diameter=proximal ICA diameter). The normal ICA diameter can therefore be calculated from direct measurement of the CCA. Three blinded observers evaluated the angiograms of 57 patients (114 carotid arteries), previously screened with duplex ultrasonography, using the NASCET, ECST, and CSI methods. In a subset of 30 patients undergoing carotid endarterectomy, comparison was also made to computerized carotid plaque planimetry., Results: The NASCET method could only be applied correctly in 89% and the ECST method in 95% of cases because of overlying vessels or inadequate views of the distal ICA or carotid bulb. An additional 9% of NASCET cases had a "negative" stenosis, in which the stenosis is wider than the distal ICA. The CSI method was applicable in 99% of cases. Interobserver comparison using ANOVA revealed significant differences using NASCET (P < .0001) and ECST (P <.001) but not CSI (P = NS). NASCET had a sevenfold variation (P < .01) and ECST a twofold variation (P < .01) in results compared with CSI. The intraobserver reliability was 0.87 for NASCET, 0.86 for ECST, and 0.90 for CSI. However, the 95% confidence intervals for an individual measurement by an observer were +/- 30% for NASCET, +/- 19% for ECST, and +/- 15% for CSI. With linear methods of measurement there were significant differences between NASCET and CSI (P < .0001) and ECST (P < .0001) but not between CSI and ECST. A comparison of area derivations of these methods to carotid plaque planimetry revealed significant differences from NASCET (P <.0001) but not ECST, CSI, or duplex methods. A CSI nomogram was created, allowing measurement of both linear and area percent stenosis., Conclusions: CSI is the most reliable validated method of measuring carotid stenosis, and it correlates with duplex and carotid pathology.

Although the traditional therapy for blunt traumatic rupture of the thoracic aorta (TRA) is immediate operative repair, there may be a selective role for delayed repair, particularly in patients with head trauma, respiratory failure, or cardiac dysfunction. The present study examines the hypothesis that TRA can be managed by selective delayed operative repair. Clinical data were collected from 59 consecutive patients with TRA at a regional trauma unit. All TRAs were at the aortic isthmus. Patients were retrospectively classified into three groups: group I (n = 12) included patients who either arrived in extremis or rapidly became unstable during triage; group II (n = 3) included patients who had no contraindications to early repair and underwent repair at the time of diagnosis; and group III (n = 44) consisted of patients who because of concomitant injuries or sepsis required initial admission and management in the intensive care unit until their clinical status had improved sufficiently to allow for deliberate delayed operative repair of the TRA. The delay ranged from 1 day to 7 months. Eight patients have yet to undergo repair and remain well at follow-up from 1 to 4 years. Overall survival rates in groups I, II, and III were 17%, 100%, and 82%, respectively. The surgery-related mortality rate in group III was 10% (three patients). Only two (4.5%) patients in group III died as a result of a ruptured aorta within 72 hours of admission. In conclusion, contrary to surgical doctrine, TRA may not require immediate operative repair in all cases, but may instead be managed selectively depending on the patient's clinical status.

Although both blunt diaphragmatic rupture (BDR) and thoracic aortic rupture (TAR) have been extensively discussed, the association of both injuries has been infrequently mentioned. The purpose of this study was to examine the current prevalence and clinical characteristics of combined BDR and TAR at an adult regional trauma unit. Among 3,886 trauma victims, 69 (1.8%) had a BDR and 44 (1.1%), a TAR. Seven patients (10% of all patients with a BDR) had both injuries. All 7 were victims of motor vehicle crashes and had a mean Injury Severity Score of 35. All TARs were just distal to the origin of the left subclavian artery. Five patients underwent repair of both injuries and survived, 1 patient had only the BDR repaired and survived, and 1 died during emergency thoracotomy, for a survival rate of 86%. Five patients had laparotomy and repair of the BDR in the presence of an unrepaired TAR. The TARs were repaired by the clamp-and-sew technique, three of them with primary repair and two with interposition tube grafts. Concomitant BDR and TAR appears to be an emerging injury complex with both diagnostic and therapeutic challenges. The presence of BDR demands a rigorous search for associated TAR.

Of a total of 225 patients with suspected thoracic outlet syndrome, 37 (16.4%) underwent surgery. Some eight patients required bilateral operations. One patient had a cervical rib and one a prominent C7 transverse process. A total of 45 limbs were operated on. Thirty-nine procedures were performed as combined scalenectomy and transaxillary first rib resection, four as two-stage scalenectomy and transaxillary first rib resection and two as simple scalenectomy alone. Follow-up from 6 to 60 (mean 17) months was available for 39 operations. A two-tier assessment method was used to improve the accuracy of the results of surgery, including the patient's own evaluation of the benefit of operation communicated to an independent observer and the surgeon's clinical appraisal. Assessment of outcome by the physician was excellent in 54%, good in 28%, fair in 10% and 8% had recurrent symptoms. Similar results were achieved in the patients' subjective evaluation with approximately 50% reporting an excellent outcome, about 40% good and 10% fair. A poor result was not recorded in those who underwent combined scalenectomy and transaxillary first rib resection. A radical surgical approach combining scalenectomy and transaxillary first rib resection is advocated to minimize the recurrence rate and improve results.

The North American (NASCET) and European (ECST) trials of carotid endarterectomy used discrepant methods to measure carotid stenosis on angiography. The aim of this study was to evaluate clinical applicability of currently available angiographic methods to measure carotid stenosis. Consecutive patients undergoing carotid angiography were evaluated. To estimate the normal internal carotid artery (ICA) bulb diameter on angiography, the common carotid artery (CCA) was used (ICA bulb diameter = 1.2 X CCA diameter measured 3-5 cm below the bifurcation) and the ICA diameter reduction was calculated: 1 - (d/1.2 X CCA) X 100%. We validated this against the planimetry of the intact removed plaque and termed it the Carotid Stenosis Index (CSI). The clinical applicability of NASCET, ECST, and CSI methods was then compared. Four observers evaluated 165 consecutive carotid angiograms performed over a 1-year period; 20% of arteries were normal, and 10% of ICAs were occluded. After these were excluded, the NASCET method was inapplicable in 30% of angiograms because of "negative stenosis" with minor degrees of atherosclerosis, inadequate views of the distal ICA, and two or more segments of distal ICA with parallel walls in which the diameters differed significantly. The ECST method gave an equivocal outline of the bulb in 10% of all angiograms. The CSI method was applicable in 97% of all angiograms, the major limitation being the presence of severe CCA atheroma (3%). The normal ICA bulb has -84% stenosis according to NASCET, whereas NASCET 0% stenosis equals 45-50% diameter reduction of ICA bulb and NASCET-positive stenoses cover only the last 50% of ICA stenoses. Although NASCET and ECST data are singularly irreplacable for surgical decisions, the angiographic methods used are discrepant from each other and of limited clinical applicability. This may affect the generalizibility of the results of these trials. CSI provides a firm scientific basis to make the results of the trials compatible., (Copyright © 1994 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: Data from recent multicenter carotid endarterectomy trials have questioned the validity and reliability of Doppler ultrasound in the assessment of carotid stenosis., Methods: We prospectively analyzed 45 patients undergoing carotid angiography to compare the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST) methods of measuring carotid stenosis with those of direct visualization ("eyeballing") and duplex ultrasound. Linear NASCET and ECST measurements were also converted into area using the pi r2 function and termed "squared NASCET" (N2) and "squared ECST" (E2). In 15 of 45 patients undergoing carotid endarterectomy, the carotid plaque was removed intact, sectioned, and photographed for computer measurement of cross-sectional area. Comparison of this "gold standard" was then made to each method of measurement., Results: Comparison between duplex and the various angiographic measurement techniques revealed significant differences between NASCET and duplex (P < .0001), ECST and duplex (P < .01), and E2 and duplex (P < .01) but not between N2, eyeballing, and carotid duplex methods. Even the NASCET and ECST methods themselves differed significantly (P < .006). When comparison was made with computerized planimetric measurements of the carotid plaque, there were significant differences for both NASCET (P < .0007) and ECST (P < .007). Correlation was demonstrated only between planimetry and N2, E2, and duplex., Conclusions: NASCET and ECST angiographic methods of measurement consistently underestimate the "true" anatomic stenosis. As such, they represent only "indexes" of carotid stenosis severity. Duplex provides a more accurate measurement of carotid stenosis.

Spontaneous renal artery dissection is an uncommon cause of renovascular hypertension, usually associated with fibromuscular dysplasia. Among reported nonautopsy cases (N = 80), arterial reconstruction has seldom been attempted (N = 21) and the outcome has frequently been poor (48% clinical failure rate). This is attributed in part to the frequent involvement of renal artery branches by the dissection. Furthermore, the report of spontaneous reversion to normotension among patients treated medically has also clouded the role of surgery in this disease. Since progress in the technique of renal artery repair now allows successful treatment of anatomically complex lesions, we reviewed our experience with arterial reconstruction in the management of spontaneous renal artery dissection to determine the frequency of and factors correlating with cure after operative repair. Ten patients (eight men, two women; mean age, 39.3 +/- 5.9 years) were admitted with severe hypertension (10/10), often associated with neurologic symptoms, hematuria, or flank pain (8/10). Serum creatinine was elevated in only two patients. Angiography demonstrated changes consistent with fibromuscular dysplasia in 7 of 10 patients and evidence of dissection in 6 of 10. Bilateral disease was present in three patients. Only five patients had a single renal artery on the involved side. The dissection extended into the primary branches in 8 of 10 patients and involved both renal arteries in four of the five patients with two arteries. Histologic study confirmed fibromuscular dysplasia in six and intramural dissection in all operative specimens. Five patients underwent revascularization (in one case requiring the ex vivo technique), with use of hypogastric artery as a conduit in four of five or resection and primary reanastomosis in one of five. Three patients became normotensive, and two returned to their previous level of blood pressure control. Follow-up averaged 14.5 years. Two patients underwent nephrectomy after exploration demonstrated nonreconstructible vessels, and two underwent nephrectomy when intraoperative assessment of the kidney showed that revascularization had failed to adequately reverse extensive renal ischemia. After a mean follow-up of 14.6 years these patients remain normotensive, although two require antihypertensive medications. One patient was treated medically and is currently hypertensive off all medications. Nine of 10 patients have maintained a normal serum creatinine during follow-up. We conclude that renal revascularization is frequently successful in spontaneous renal artery dissection (five of seven, 71.4%) and results in sustained relief of hypertension with maximal conservation of renal tissue. This is important because of the young age at onset and the not infrequent occurrence of bilateral fibromuscular dysplasia, and even of dissection.(ABSTRACT TRUNCATED AT 400 WORDS)

The authors describe what they believe is the first report in the radiology literature of two coexisting, adjacent false aneurysms of the radial artery. They occurred in a 33-year-old man who had had cannulation of the radial artery during the management of multiple injuries sustained in a motor vehicle accident. Radial artery aneurysms are uncommon. Definitive treatment of false aneurysms of the radial artery consists of surgical excision with ligation of the artery or, if obstruction is demonstrated preoperatively, end-to-end anastomosis of the artery.

Catheterization of the totally occluded iliac artery prior to percutaneous transluminal angioplasty is frequently difficult. We report a patient in whom such an occlusion was traversed by a combined antegrade-retrograde approach, following which angioplasty was successfully performed.