Biomedical subjects

Eva M Rzucidlo

Publications and source records attributed to Eva M Rzucidlo.

13 recordsLinked to original sources

PubMed2006

Shifting Wallgraft position: case reports and review of the forces affecting Wallgraft positioning.

Extensive use of stent-grafts in the iliac arteries is an increasingly common endovascular alternative to an aortobifemoral bypass procedure. The treatment of diffuse bilateral disease is frequently performed by using the technique of paired stent-grafts in the proximal common iliac arteries to effectively re-create the aortic-bifurcation. We present three patients treated with this technique who returned with recurrent occlusive disease. During subsequent treatment, the stent-grafts were noted to be in different positions from where they were initially deployed. A discussion of the possible explanations for the shifting positions follows.

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PubMed2005

Outcomes of renal artery angioplasty and stenting using low-profile systems.

OBJECTIVE: Renal artery percutaneous transluminal angioplasty (RPTA) and stenting (RAS) are accepted therapies for selected patients with renovascular hypertension and chronic renal insufficiency. We evaluated the outcomes and complications of RAS performed by vascular surgeons at our institution with modern low-profile systems. METHOD: We retrospectively analyzed all RPTA and RAS procedures attempted with the use of low-profile systems from June 2000 to September 2003. Eighty-two patients (96 arteries) with atherosclerotic renal artery stenosis were treated. Indication for treatment was hypertension in 44 (54%) and chronic renal insufficiency in 38 (46%). Technical success, complication rates, clinical success for control of hypertension or renal insufficiency, restenosis, and survival were reviewed with a mean follow-up of 1 year. RESULTS: Ninety-three arteries were treated with stents, three with RPTA only. Primary technical success was 95%, with 98% overall technical success. Major complications occurred in 6.1% and minor complications in 1.2%. Hypertension was improved in 81% at 1 year. Renal function was improved in 23%, stable in 53%, and worse in 24% at 1 year. Restenosis was seen by routine duplex surveillance in 25% at 1 year. Restenosis associated with clinical deterioration and confirmed by angiogram was seen in 10%. The overall 3-year survival was 83%. CONCLUSION: RPTA/RAS can be performed with low-profile systems with excellent technical success, low complication rates, and clinical outcomes that compare favorably with prior reports.

Angioplasty, Balloon↗

PubMed2005

Endothelial cell activation of the smooth muscle cell phosphoinositide 3-kinase/Akt pathway promotes differentiation.

OBJECTIVE: Interactions between endothelial cells (ECs) and smooth muscle cells (SMCs) are fundamental in diverse cardiovascular processes such as arteriogenesis, atherosclerosis, and restenosis. We aimed to determine the intracellular signaling mechanisms by which ECs promote a differentiated SMC phenotype. METHODS: Bovine thoracic aorta ECs and SMCs were isolated and cultured. For co-culture studies, ECs were grown to confluence on one side of a semi-permeable Cyclopore membrane. SMCs were then plated on the opposite side of the membrane and cultured for 24 to 48 hours. For adenovirus experiments, SMCs were infected prior to plating opposite ECs. For conditioned media studies, SMCs cultured alone on plastic were treated with media harvested from EC/SMC in co-culture. SMC phenotype was assayed by microscopy and measurement of two-dimensional area, or by western blotting for contractile protein markers of differentiation. Akt activation was measured by western blotting for phospho-Serine 473. RESULTS: Although SMCs cultured alone exhibit a dedifferentiated synthetic phenotype, we report that bilayer co-culture with ECs induced a differentiated SMC phenotype as measured by morphology and cell area and expression of protein markers of differentiation, including contractile proteins and the cyclin-dependent kinase inhibitor p27 kip . The EC/SMC bilayer co-culture resulted in activation of the SMC protein kinase Akt, with no effect on total Akt expression. Similarly, conditioned media from co-cultured EC/SMC promoted rapid Akt phosphorylation and subsequent expression of differentiation protein markers in SMCs cultured alone. Adenoviral overexpression of constitutively active Akt in SMCs cultured alone mimicked the ability of ECs to induce SMC differentiation. Notably, inhibition of phosphoinositide 3 (PI 3)-kinase activity with wortmannin or adenoviral overexpression of a dominant-negative Akt prevented the EC-mediated effect on SMC morphology and differentiation protein marker expression. CONCLUSIONS: ECs direct SMCs towards a differentiated phenotype through activation of the SMC PI 3-kinase/Akt pathway. CLINICAL RELEVANCE: Interactions between endothelial cells (ECs) and smooth muscle cells (SMCs) are fundamental in diverse cardiovascular processes such as arteriogenesis, collateral blood vessel development, atherosclerosis, and restenosis. Alterations in SMC phenotype occur in each of these processes. Endothelial denudation has been suggested to contribute to the SMC proliferative response to vessel injury by angioplasty or other catheterization procedures. We have employed a co-culture approach to dissect the molecular signals that are dependent on the spatial relationship between ECs and SMCs, and have identified the importance of the PI3K/Akt pathway in EC-induced SMC differentiation. This pathway may suggest targets for therapeutic interventions for intimal hyperplasia and restenosis.

Animals↗

PubMed2005

Restenosis in gold-coated renal artery stents.

BACKGROUND: Gold coating improves stent visibility under fluoroscopy. This is particularly valuable for precise stent placement during renal artery stenting (RAS). There is conflicting evidence regarding restenosis with gold-coated stents. To evaluate the effect of gold coating on restenosis after renal stenting, we reviewed the results of all patients undergoing RAS in our practice. METHODS: A retrospective cohort study of all patients undergoing RAS between June 2000 and September 2003 was performed. During this time, both gold-coated and stainless steel stents were used. Restenosis (>60% diameter) was determined by serial follow-up duplex exams (peak systolic velocity >180 cm/s and renal-aortic ratio >3.5). Restenosis rates were determined by using the Kaplan-Meier life-table method. Variables potentially affecting restenosis were evaluated with the log-rank test and Cox proportional hazards modeling. RESULTS: RAS was performed in 97 arteries (78 patients). Gold-coated (NIRoyal) stents were placed in 59 arteries (48 patients). Stainless steel stents (Corinthian, Genesis, and Herculink) were placed in 38 arteries (34 patients). Patient demographics, indication for treatment, technical success, and complications did not differ between gold and stainless steel stent groups. Mean follow-up was 15 months for gold-coated stents and 18 months for stainless steel stents (NS). By life-table method, 1-year and 2-year freedom from restenosis rates were 84% and 78% in arteries treated with stainless steel stents versus 69% and 39% in those treated with gold-coated stents (P = .012, log-rank test). By multivariate analysis, only the use of gold-coated stents (P = .018; hazard ratio [HR], 3.3; 95% confidence interval [CI], 1.2 to 8.7) and bilateral disease (P = .046; HR, 2.3; 95% CI, 1.02 to 5.2) predicted restenosis. Stent diameter, patient demographics, and indication for RAS had no effect on restenosis by univariate analysis. According to American Heart Association criteria, 87% of patients in the stainless steel group had improved blood pressure at 1 year, compared with 77% in the gold-coated stent group (Kaplan-Meier; P = .042, log-rank test). There were no significant differences in the effect of RAS on serum creatinine levels between the two groups. CONCLUSION: Gold-coated renal stents had a substantially higher rate of restenosis than stainless steel stents in our series. These findings have led us to abandon the use of gold-coated stents for RAS. Patients who have received gold-coated stents for the treatment of atherosclerotic renal artery stenosis should be followed closely for evidence of restenosis.

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PubMed2005

Mesenteric stenting for chronic mesenteric ischemia.

BACKGROUND: Mesenteric stenting has not been widely adopted for the treatment of chronic mesenteric ischemia (CMI). The recent availability of embolic protection and low-profile devices with the theoretical ability to decrease perioperative bowel necrosis, led us to begin using mesenteric stenting for patients with CMI. We review our initial experience to examine short-term outcomes. METHODS: We performed a retrospective analysis of all patients who were treated by vascular surgeons with mesenteric stenting for CMI. Patients with acute mesenteric ischemia were excluded. We evaluated perioperative morbidity and mortality, restenosis, recurrent symptoms, and reintervention. Kaplan-Meier methods were used to assess events during follow-up. We also compared these outcomes with a historical control group of patients treated with open surgical revascularization. RESULTS: Fourteen patients underwent mesenteric stenting over the past 3 years. Mean age was 73, and 64% were women. There was no perioperative or 30-day mortality or major morbidity. Early restenosis and recurrent symptoms occurred in 10% and 9% of patients at 6 months. At a mean follow-up of 13 months, 53% of patients underwent reintervention. However, 93% were symptom-free at their last follow-up. Compared with open surgery, stent patients had lower perioperative major morbidity (30% vs 0%, P < .01) and shorter hospital and intensive care unit length of stay (median 10 days vs 2 days, and 3 days vs 0 days, respectively, P < .01 for both). However, stent patients were seven times as likely to develop restenosis (P < .01), four times more likely to develop recurrent symptoms (P < .01), and 15 times more likely to undergo reintervention (P < .01). There was one death 13 months after stenting due to mesenteric infarction in a patient lost to follow-up. One patient was successfully converted to open surgery after a second restenosis. He had regained 20 pounds and was determined to be a better operative candidate than at his initial presentation. There was no perioperative or 30-day mortality or major morbidity with reintervention after mesenteric stenting. CONCLUSION: Mesenteric stenting for CMI can be performed with low perioperative risk. However, stenting is associated with early restenosis and recurrent symptoms requiring secondary procedures. Patients with severe nutritional depletion or high surgical risk may benefit from mesenteric stenting for CMI, but close follow-up is required. Later open surgery can be performed for restenosis if nutritional status and surgical risk are improved, or repeat angioplasty and stenting can be effectively performed if operative risk remains high.

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PubMed2004

Anatomic characteristics of ruptured abdominal aortic aneurysm on conventional CT scans: Implications for rupture risk.

OBJECTIVE: The purpose of this study was to analyze anatomic characteristics of patients with ruptured abdominal aortic aneurysms (AAAs), with conventional two-dimensional computed tomography (CT), including comparison with control subjects matched for age, gender, and size. METHODS: Records were reviewed to identify all CT scans obtained at Dartmouth-Hitchcock Medical Center or referring hospitals before emergency AAA repair performed because of rupture or acute severe pain (RUP group). CT scans obtained before elective AAA repair (ELEC group) were reviewed for age and gender match with patients in the RUP group. More than 40 variables were measured on each CT scan. Aneurysm diameter matching was achieved by consecutively deleting the largest RUP scan and the smallest ELEC scan to prevent bias. RESULTS: CT scans were analyzed for 259 patients with AAAs: 122 RUP and 137 ELEC. Patients were well matched for age, gender, and other demographic variables or risk factors. Maximum AAA diameter was significantly different in comparisons of all patients (RUP, 6.5 +/- 2 cm vs ELEC, 5.6 +/- 1 cm; P <.0001), and mean diameter of ruptured AAAs was 5 mm smaller in female patients (6.1 +/- 2 cm vs 6.6 +/- 2 cm; P =.007). Two hundred patients were matched for diameter, gender, and age (100 from each group; maximum AAA diameter, 6.0 +/- 1 cm vs 6.0 +/- 1 cm). Analysis of diameter-matched AAAs indicated that most variables were statistically similar in the two groups, including infrarenal neck length (17 +/- 1 mm vs 19 +/- 1 mm; P =.3), maximum thrombus thickness (25 +/- 1 mm vs 23 +/- 1 mm, P =.4), and indices of body habitus, such as [(maximum AAA diameter)/(normal suprarenal aorta diameter)] or [(maximum AAA diameter)/(L3 transverse diameter)]. Multivariate analysis controlling for gender indicated that the most significant variables for rupture were aortic tortuosity (odds ratio [OR] 3.3, indicating greater risk with no or mild tortuosity), diameter asymmetry (OR, 3.2 for a 1-cm difference in major-minor axis), and current smoking (OR, 2.7, with the greater risk in current smokers). CONCLUSIONS: When matched for age, gender, and diameter, ruptured AAAs tend to be less tortuous, yet have greater cross-sectional diameter asymmetry. On conventional two-dimensional CT axial sections, it appears that when diameter asymmetry is associated with low aortic tortuosity, the larger diameter on axial sections more accurately reflects rupture risk, and when diameter asymmetry is associated with moderate or severe aortic tortuosity, the smaller diameter on axial sections more accurately reflects rupture risk. Current smoking is significantly associated with rupture, even when controlling for gender and AAA anatomy.

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PubMed2003

The mTOR/p70 S6K1 pathway regulates vascular smooth muscle cell differentiation.

Vascular smooth muscle cells (VSMC) in mature, normal blood vessels exhibit a differentiated, quiescent, contractile morphology, but injury induces a phenotypic modulation toward a proliferative, dedifferentiated, migratory phenotype with upregulated extracellular matrix protein synthesis (synthetic phenotype), which contributes to intimal hyperplasia. The mTOR (the mammalian target of rapamycin) pathway inhibitor rapamycin inhibits intimal hyperplasia in animal models and in human clinical trials. We report that rapamycin treatment induces differentiation in cultured synthetic phenotype VSMC from multiple species. VSMC treated with rapamycin assumed a contractile morphology, quantitatively reflected by a 67% decrease in cell area. Total protein and collagen synthesis were also inhibited by rapamycin. Rapamycin induced expression of the VSMC differentiation marker contractile proteins smooth muscle (SM) alpha-actin, calponin, and SM myosin heavy chain (SM-MHC), as observed by immunoblotting and immunohistochemistry. Notably, we detected a striking rapamycin induction of calponin and SM-MHC mRNA, suggesting a role for mTOR in transcriptional control of VSMC gene expression. Rapamycin also induced expression of the cyclin-dependent kinase inhibitors p21(cip) and p27(kip), consistent with cell cycle withdrawal. Rapamycin inhibits mTOR, a signaling protein that regulates protein synthesis effectors, including p70 S6K1. Overexpression of p70 S6K1 inhibited rapamycin-induced contractile protein and p21(cip) expression, suggesting that this kinase opposes VSMC differentiation. In conclusion, we report that regulation of VSMC differentiation is a novel function of the rapamycin-sensitive mTOR signaling pathway.

Animals↗

PubMed2003

Stent-graft treatment of a large internal carotid artery vein graft aneurysm.

Aneurysm degeneration of internal carotid artery interposition vein grafts can occur, and their repair can be complicated by repeated neck dissection and difficulty in obtaining distal artery control. We used a covered stent graft to exclude a large internal carotid artery interposition vein graft aneurysm. Retrograde flow was induced in the internal carotid artery so that an embolization protection balloon could be placed through the aneurysm. The stent graft was then placed with embolization protection. The repair was performed without complication, and the aneurysm remained successfully excluded at 6-month follow-up.

Aneurysm↗

PubMed2003

Early results of stent-grafting to treat diffuse aortoiliac occlusive disease.

INTRODUCTION: Diffuse aortoiliac occlusive disease or isolated external iliac artery occlusion >or=10 cm long typically are treated with surgical bypass grafting because of limited durability of stent placement. We evaluated the results of stent-graft placement as an option for treatment of these diseases. METHODS: Demographic data for patients undergoing stent-grafting in one or more iliac artery segments were recorded. Technical, clinical, and hemodynamic success, and aortoiliac primary and secondary patency were analyzed with Society for Vascular Surgery/American Association for Vascular Surgery criteria. RESULTS: Thirty-four consecutive patients underwent stent-graft treatment because of rest pain (65%) or tissue loss (35%). Mean patient age was 63 years, and 38% of patients were women. Ninety-one percent of patients had hypertension, 71% had coronary artery disease, 21% had renal insufficiency (serum creatinine > 2.0 mg/dL), and 26% had diabetes; 71% were active smokers. TransAtlantic Inter-Society Consensus C or D disease was present in 85% of patients, complete common or external iliac artery occlusion was present in 41%, and external iliac artery disease requiring treatment was present in 94% of patients. Mean lesion length was 13.7 +/- 8 cm. Technical, hemodynamic, and clinical success was achieved in all patients in whom the lesion could be crossed with a wire. Ankle-brachial index increased from.30 +/-.03 to.59 +/-.04. Self-expanding stent grafts were used (Wallgraft, Boston Scientific, Boston, Mass, in 88% of patients; Viabahn, W. L. Gore, Flagstaff, Ariz, in 12% of patients). Concomitant common femoral endarterectomy was performed in 53% of patients. At 12 months, primary patency was 70% and primary assisted patency was 88%. Four stent grafts became occluded because of distal external iliac artery or proximal common femoral artery disease, which required subsequent common femoral endarterectomy and either external iliac artery stent grafting or extraanatomic bypass grafting. Eighty percent (four of five) of primary patency failures were in patients who did not undergo concomitant common femoral endarterectomy at initial stent graft placement. CONCLUSION: Early results of stent-graft placement to treat diffuse aortoiliac occlusive disease appear better than our recent experience with stenting alone. Concomitant common femoral endarterectomy or better assessment of femoral disease may improve durability.

Adult↗

PubMed2003

Blinded comparison of preoperative duplex ultrasound scanning and contrast arteriography for planning revascularization at the level of the tibia.

PURPOSE: We examined whether preoperative duplex ultrasound scanning (DU) could replace contrast material-enhanced arteriography (CA) in selecting the recipient artery of tibial or peroneal artery bypass grafts. METHODS: In patients who underwent tibial or peroneal artery bypass grafting because of critical ischemia, images were obtained of the lower extremity arterial circulation with both DU and CA. Vascular surgeons, blinded to the operation performed, reviewed either DU or CA images for arterial visualization and patency. The tibial or peroneal artery best suited to receive the bypass graft was selected by surgeons using only data from either DU or CA images. This selection was compared with the artery actually used at bypass surgery. RESULTS: Preoperative DU and CA data for 40 lower extremities in 38 patients undergoing bypass grafting at the level of the tibia provided 110 arteries: 38 anterior tibial arteries, 32 peroneal arteries, and 40 posterior tibial arteries. Ten arteries (8 peroneal, 2 anterior tibial) were not identified with DU, and 1 artery (anterior tibial) was not identified with CA. DU enabled prediction of the artery actually used in 88% of patients (35 of 40), whereas CA enabled prediction of the artery actually used in 93% of patients (37 of 40; P =.59). Duplicate findings at DU and CA enabled selection of 85% of arteries actually used (95% confidence interval, 71%-93%). Arteries used for bypass grafting had significantly higher peak systolic velocity (35 cm/s vs 25 cm/s; P =.04), higher end-diastolic velocity (15 cm/s vs 9 cm/s; P =.005), and greater diameter (2.4 mm vs 1.7 mm; P =.003) compared with arteries not selected for bypass grafting. CONCLUSION: Findings at DU and CA typically agree when used to select tibial or peroneal arteries for bypass grafting. With DU there is occasional difficulty in identification of the peroneal artery, but selection of the actual artery used is accurate. Peak systolic velocity, end-diastolic velocity, and diameter characteristics correlate with arteriographic criteria for tibial bypass target artery selection. If DU enables adequate identification of a target artery for bypass grafting, and especially if the peroneal artery is seen, findings at CA are not likely to alter bypass execution.

Adult↗

PubMed2003

Endovascular repair of abdominal aortic aneurysm without preoperative arteriography.

OBJECTIVE: Clinical trials of endovascular aortic aneurysm repair (EVAR) have required both preoperative aortography and computed tomography (CT). We codeveloped specialized three-dimensional (3-D) reconstruction and computer-aided measurement, planning, and simulation software (3-D CAMPS) based on CT or magnetic resonance imaging, to eliminate the need for preoperative arteriography. METHODS: EVAR with 3-D CAMPS as the sole preoperative imaging method was performed in 196 patients from 1996 to 2001, with six endograft types in three configurations. Physical examination, abdominal radiography, and CT (3D-CAMPS) were performed at 1, 6, and 12 months, then annually. RESULTS: For a subset of cases in which a comparison could be made, 3-D CAMPS was superior to angiography for prediction of endograft length and iliac access. Hospital mortality was zero, and 30-day mortality was 0.5%. In three patients immediate conversion to open repair (1.5%) was necessary because of previously unknown stent-graft mechanical limits. Incidence of endoleak was 15% at 1 month, 10% at 6 months, 6% at 12 months, and 7% at 24 months, and 92% of endoleaks were type II. Mean follow-up was 18 months. Aneurysm-related mortality was zero. Nineteen secondary procedures (all endovascular) were performed in 16 patients (8%). For all graft types, freedom from secondary procedure was 94% at 1 year and 90% at 2 years, and this was better for endografts ultimately approved by the US Food and Drug Administration (96% at 1 year, 95% at 2 years; P =.02). No known measurement-related complications occurred in the series. Results for secondary intervention and endoleak compare favorably to series with similar endograft types. CONCLUSIONS: EVAR can be performed with 3-D CAMPS as the sole preoperative imaging method to achieve outcomes comparable to the best series published for each endograft type. CT with 3-D CAMPS can effectively eliminate the need for preoperative arteriography and avert associated morbidity, expense, and exposure to contrast agent and radiation.

Aged↗

PubMed2002

Prediction of early graft failure with intraoperative completion duplex ultrasound scan.

PURPOSE: The purpose of this study was to determine intraoperative hemodynamic parameters that predict early failure of infragenicular vein grafts with intraoperative completion duplex ultrasound scan. METHODS: We reviewed the results of intraoperative duplex scans that were selectively performed after completion of 45 tibial/pedal vein bypass grafts at high risk for failure. Bypass was performed for rest pain (39%) or tissue loss (61%), and 60% of the cases were disadvantaged because of compromised vein quality or poor arterial outflow. A 10-MHz low-profile transducer was used to scan the entire graft at bypass completion. All grafts were determined to be technically adequate (absence of retained valves, arteriovenous fistulas, or localized velocity increases and the presence of bypass-dependent distal pulses). Peak systolic velocity (PSV) and end diastolic velocity (EDV) were also measured at each anastomosis, in the outflow artery and in the proximal and distal portions of each graft. Resistive indices (RI) were calculated at each measurement point (PSV-EDV/PSV). Statistical analysis was performed with unpaired t test, chi(2) test, and multivariate analyses. RESULTS: Twenty infragenicular vein bypass grafts (44%) thrombosed within 12 months. Intraoperative hemodynamic parameters were significantly different between grafts that remained patent or thrombosed. EDV was lower (5 +/- 1 cm/s versus 13 +/- 3 cm/s; P =.02) and RI was higher (0.90 versus 0.81; P <.01) in the proximal portions of grafts that thrombosed within 12 months. Distal EDV was also lower (6 +/- 1 cm/s versus 15 +/- 2 cm/s; P <.01) and distal RI was higher (0.89 versus 0.78; P <.01) in grafts that thrombosed. With multivariate analysis, only low distal EDV was predictive of early graft failure (P <.05). Distal bypass EDV of less than 8 cm/s predicated early graft thrombosis with 76% sensitivity and 75% specificity (positive predictive value, 71%; negative predictive value, 78%). Absence of diastolic flow (EDV of 0 cm/s) predicted early graft failure with 100% specificity and 100% positive predictive value. CONCLUSION: In this initial experience, low EDV measured with intraoperative duplex scan was associated with early thrombosis of tibial level vein grafts. When such values are observed, measures should be taken to improve graft hemodynamic parameters. Prospective study of infragenicular vein bypass grafts may better define hemodynamic parameters predictive of early graft thrombosis.

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PubMed2002

Internal iliac occlusion without coil embolization during endovascular abdominal aortic aneurysm repair.

PURPOSE: When abdominal aortic aneurysms and common iliac artery (CIA) aneurysms undergo concomitant endovascular repair, endograft limb extension into the external iliac artery is often necessary. Usually, the internal iliac artery (IIA) is coil embolized in such a case to prevent endoleak. It has been our practice to coil embolize the IIA only in cases where there is not adequate stent graft seal in the CIA immediately proximal to the IIA origin (effectively sealing the entire IIA origin). In this study, we evaluated the outcomes of this approach. METHODS: We retrospectively reviewed 204 consecutive endovascular abdominal aortic aneurysm repairs at Dartmouth-Hitchcock Medical Center from 1996 to 2001. Computed tomographic angiography with three-dimensional reconstruction was the primary preoperative imaging modality, and the decision to cover the IIA without concomitant coil embolization was based before surgery on the presence of adequate graft oversizing (> or =10% to 15%) in the most distal 5 mm of CIA and 15 mm of proximal external iliac artery, respectively. RESULTS: The IIA was occluded 33 times in 31 patients. In 22 cases (67%), the IIA was covered without coil embolization (COVER group). The remaining 11 patients (33%) with inadequate graft oversizing in the CIA underwent IIA coil embolization (COIL group). The follow-up periods for the COVER and COIL groups were 19 +/- 2 months and 10 +/- 3 months, respectively. All operations in both groups were technically successful without evidence of endoleak at completion angiography. No endoleaks, graft migrations, or aneurysm enlargements were associated with the covered or coiled IIAs during the follow-up period. No clinical sequelae were seen in the COVER group, with the exception of buttock claudication in six patients (27%) that resolved completely in five patients. In the COIL group, five patients (45%) had buttock claudication. In addition, one case of buttock necrosis and one case of ischemic neuropathy occurred in the COIL group. CONCLUSION: Covering the IIA without coiling effectively excluded the CIA aneurysm in every case and was associated with a low incidence rate of complications compared with coil embolization. With detailed preoperative imaging and patient selection, IIA coil embolization may not be necessary in as many as two thirds of patients who need IIA occlusion.

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