SUPERA Interwoven Nitinol Stent Outcomes in Above-Knee IntErventions (SAKE) Study

PurposeTo report experience with the novel interwoven-wire self-expanding nitinol SUPERA stent (IDEV Technologies, Inc/Abbott Laboratories, Inc, Webster, Texas) for the treatment of severely diseased superficial femoral and popliteal arteries.Materials and MethodsConsecutive patients with severely diseased superficial femoral and popliteal arteries who received SUPERA stents (n = 80 patients [98 limbs]; mean age, 70.8 y; 80% male) were retrospectively identified. Patients were followed for an average of 14.3 months after intervention.ResultsTotal occlusions were present in 39% of the lesions, 21% had tissue loss, and 61% demonstrated calcification on fluoroscopy. Patients were prescribed dual antiplatelet therapy (aspirin and clopidogrel) for at least 30 days unless contraindicated, followed by aspirin alone indefinitely. The mean (± SD) lesion length was 143 mm (± 98). Based on need for clinical intervention, primary patency was 96.9% at 6 months and 85.8% at 12 months (Kaplan-Meier estimates). Assisted primary patency and secondary patency rates at 12 months were 96.8% and 100%, respectively. Ankle-brachial index increased from 0.60 at baseline to 0.83 at last follow-up (P < .001). No stent fractures were found by fluoroscopy inspection in 19 limbs (16 patients) that required reintervention.ConclusionsBased on experience with multiple operators at a single clinical center, the interwoven nitinol stent design provides a viable option for high-grade obstructive disease in the femoropopliteal artery.     

Targeting and Recanalization after Embolization with Calibrated Resorbable Microspheres versus Hand-cut Gelatin Sponge Particles in a Porcine Kidney Model

PurposeTo report on polyethylene glycol hydrogel-based resorbable embolization microspheres (REM) that were synthesized to resorb in < 24 hours, before inflammation and vascular remodeling, to achieve a complete arterial recanalization and to compare targeting and recanalization of REM of 300–500 µm, 500–700 µm, and 700–900 µm with hand-cut gelatin sponge particles (GSP).Materials and MethodsEight pigs underwent polar renal artery embolization with REM or GSP. Angiograms were obtained before embolization and 10 minutes and 7 days after embolization before pigs were sacrificed to determine the occlusion level, the percentage of occlusion, and the recanalization rate for each product. The distribution of embolic material was assessed in pathology, and infarction rate of the kidneys was measured.ResultsREM of 300–500 µm occluded more distal vessels than REM of 500–700 µm and 700–900 µm. At day 7, the recanalization rate was complete for the larger REM, whereas it was about 60% for the two smaller sizes. REM were completely degraded, with no residual material or inflammation. GSP occluded more proximal arteries than REM of 700–900 µm, were partly degraded at day 7, and were accompanied by a foreign body reaction in proximal and distal arteries. GSP recanalized at 79%. The infarction rate was higher with the two smaller sizes of REM and with GSP than with the largest REM.ConclusionsREM of different sizes targeted different occlusion levels in kidney arteries. GSP provided an extended occlusion level without actual targeting. Regardless of embolic material used, angiographic recanalization of renal arteries depended on the extent of necrosis. REM of 700–900 µm demonstrated the lowest infarction rate and the best recanalization rate.     

Role of C-Arm CT in Identifying Caudate Arteries Supplying Hepatocellular Carcinoma

PurposeTo evaluate the role of C-arm computed tomography (CT) performed at the proper hepatic artery or equivalent in patients with caudate-lobe hepatocellular carcinoma (HCC) for the detection of tumor-feeding arteries during chemoembolization.Materials and MethodsFrom July 2009 to June 2012, 1,785 patients received initial chemoembolization at a single institution. Among them, 52 patients with caudate HCC underwent initial chemoembolization with the use of C-arm CT. C-arm CT images were obtained at the proper hepatic artery or equivalent. Two radiologists reviewed the C-arm CT scans and angiograms in consensus. The cumulative local recurrence rate was calculated by the Kaplan–Meier method.ResultsTumor-feeding arteries were single (n = 31), double (n = 12), triple (n = 6), and quadruple (n = 3). Seventy-nine tumor-feeding arteries and their origins in 48 patients were demonstrated on C-arm CT. In four patients (7.7%), five tumor-feeding arteries were not clearly indicated on C-arm CT because of poor image quality caused by failure of the patients to hold their breath. Selective chemoembolization via tumor-feeding arteries was successful in 45 patients (87%). The cumulative local recurrence rates at 6 months, 1 year, and 3 years were 19.4%, 32.8%, and 35.8%, respectively. Nonselective chemoembolization of tumor-feeding arteries of caudate-lobe HCC was a significantly important factor in higher cumulative local recurrence rates (hazard ratio, 3.916; 95% confidence interval, 1.367–11.216; P = .011).ConclusionC-arm CT obtained at the proper hepatic artery or equivalent level can demonstrate most tumor-feeding arteries supplying HCCs in the caudate lobe.     

Combined Antegrade Femoral Artery and Retrograde Popliteal Artery Recanalization for Chronic Occlusions of the Superficial Femoral Artery

PurposeTo evaluate the efficacy and safety of a dual femoral–popliteal approach in the supine position after failed antegrade recanalization attempts in chronic total occlusion (CTO) of the superficial femoral artery (SFA).Materials and MethodsFrom May 2011 to October 2012, 21 patients underwent dual femoral–popliteal recanalization for CTO of the SFA, with a mean lesion length of 87.4 mm ± 5.8. When contralateral antegrade recanalization of SFA occlusions via the common femoral artery could not be achieved, the occlusions were intrainterventionally accessed by retrograde approach via the popliteal artery, which was punctured anteriorly with gently flexed knee and crus extorsion. When the SFA had been recanalized, further angioplasty and stent placement procedures were completed via the femoral artery.ResultsA technical success rate of 100% (entailing puncture of the popliteal artery and SFA recanalization) was achieved, and no hemorrhage, hematoma, pseudoaneurysm, arteriovenous fistula, or other complications developed. During a mean follow-up of 9.8 months ± 1.5, claudication severity, rest pain, and toe ulcers improved significantly. The pulse of the distal arteries, as well as the filling of the veins, could be distinctly felt. Ankle-brachial index changed from 0.48 ± 0.17 to 0.84 ± 0.11 at 1 year after intervention (P < .001), and patency rates at 1, 6, and 12 months after interventions were 100%, 80%, and 42%, respectively.ConclusionsA dual femoral–popliteal approach in the supine position is an alternative backup option after failed attempts at the antegrade approach for patients with proximal barriers in CTO or lesions with major extending collateral vessels.     

Early Treatment Response Evaluation after Yttrium-90 Radioembolization of Liver Malignancy with CT Perfusion

PurposeTo evaluate computed tomography (CT) perfusion for assessment of early treatment response after transarterial radioembolization of patients with liver malignancy.Materials and MethodsDynamic contrast-enhanced CT liver perfusion was performed before and 4 weeks after transarterial radioembolization in 40 patients (25 men and 15 women; mean age, 64 y ± 11; range, 35–80 y) with liver metastases (n = 27) or hepatocellular carcinoma (HCC) (n = 13). Arterial perfusion (AP) of tumors derived from CT perfusion and tumor diameters were measured on CT perfusion before and after transarterial radioembolization. Success of transarterial radioembolization was evaluated on morphologic follow-up imaging (median follow-up time, 4 mo) based on Response Evaluation Criteria in Solid Tumors (Version 1.1). CT perfusion parameters before and after transarterial radioembolization for different response groups were compared. Kaplan-Meier curves were plotted to illustrate overall 1-year survival rates.ResultsLiver metastases showed significant differences in AP before and after transarterial radioembolization in responders (P < .05) but not in nonresponders (P = .164). In HCC, AP values before and after transarterial radioembolization were not significantly different in responders and nonresponders (P = .180 and P = .052). Tumor diameters were not significantly different on CT perfusion before and after transarterial radioembolization in responders and nonresponders with liver metastases and HCC (P = .654, P = .968, P = .148, P = .164). In patients with significant decrease of AP in liver metastases after transarterial radioembolization, 1-year overall survival was significantly higher than in patients showing no reduction of AP.ConclusionsCT perfusion showed early reduction of AP in liver metastases responding to transarterial radioembolization; tumor diameter remained unchanged early after treatment. No significant early treatment response to transarterial radioembolization was found in patients with HCC. In patients with liver metastases, a decrease of AP after transarterial radioembolization was associated with a higher 1-year overall survival rate.     

Extracellular Traps in Lipid-Rich Lesions of Carotid Atherosclerotic Plaques: Implications for Lipoprotein Retention and Lesion Progression

PurposeTo investigate the presence and location of extracellular traps (ETs) in atherosclerotic plaques and to determine whether they are spatially associated with inflammatory cells and the lipid core.Materials and MethodsHuman carotid atherosclerotic plaques were collected from seven patients after surgical endarterectomy. Sequential tissue sections were stained with hematoxylin-eosin or subjected to immunohistochemistry to detect ETs, neutrophils and macrophages or apolipoprotein B (ApoB). To demonstrate the specificity of the antibody used to detect ETs, the adjacent tissue section was pretreated with deoxyribonuclease-1 (DNase-1) before immunostaining for ETs.ResultsAll seven carotid plaques demonstrated advanced atherosclerotic lesions. Extensive ET and ApoB immunostaining was detected predominantly within the acellular lipid core. Along the edges of the lipid core, confocal microscopy revealed areas suggestive of active release of ETs from MPO-positive cells. Pretreatment of tissue sections with DNase-1 abolished ET signal in the extracellular matrix, but not the signal within the cells along the margins of the core.ConclusionsThe localization of ETs to the lipid core suggests a possible binding site for lipoproteins, which may further promote lesion progression and inflammation.     

Early Initiation of Enteral Feeding in Cancer Patients after Outpatient Percutaneous Fluoroscopy-Guided Gastrostomy Catheter Placement

PurposeTo report the results of early enteral feeding in patients with cancer after outpatient placement of a percutaneous fluoroscopy-guided gastrostomy (PFG).Materials and MethodsFrom January 2008 through December 2008, 121 consecutive patients with cancer underwent outpatient placement of a PFG for nutrition. Of these patients, 118 patients met criteria for early feeding, and 113 were successfully fed early (after at least 3 hours). Of the patients fed early, 5 had insufficient follow-up for further analysis leaving 108 patients for outcomes analysis. After placement of the PFG, patients were put on low-wall suction via the PFG for 1 hour followed by feeding via the PFG at least 3 hours after placement. Follow-up evaluation was done the next business day. The medical records were reviewed for 30-day outcomes of early feeding, technical aspects of the procedures, and complications.ResultsAfter placement of the PFG, 98% (118 of 121) of patients met criteria for early feeding, and 93% (113 of 121) of patients were successfully fed early. The median time between the end of the procedure and initiation of feeding was 4 hours (interquartile range, 3.7–4.4 h). The 30-day minor complication rate was 14% (15 of 108), and the 30-day major complication rate was 1% (1 of 108). No complications were directly attributable to early feeding.ConclusionsEarly initiation of tube feedings after outpatient placement of a PFG was well tolerated in patients with cancer and carried comparable risks to previously reported results using traditional delayed feeding protocols. Early feeding provided patients with prompt enteral nutrition and eliminated the need for routine hospital admission after the procedure.     

Apparent Diffusion Coefficient of Uterine Leiomyoma as a Predictor of the Potential Response to Uterine Artery Embolization

PurposeTo determine the utility of the apparent diffusion coefficient (ADC) of uterine leiomyoma for prediction of the potential response to uterine artery embolization (UAE).Materials and MethodsThis prospective study included 49 patients with uterine leiomyomas who underwent diffusion-weighted magnetic resonance (MR) imaging before UAE between May 2011 and January 2012. All patients also underwent 3-month follow-up MR imaging after UAE. Using conventional and diffusion-weighted MR imaging sequences, 72 uterine leiomyomas ≥ 3 cm were prospectively evaluated. The volume of each leiomyoma was calculated, and quantitative measurement of ADC was performed. Regression analysis was used to evaluate the relationship between ADC and volumetric response after UAE. Receiver operating characteristic curve analysis was performed to determine the sensitivity and specificity of ADC for prediction of the potential response to UAE. Interclass correlation coefficient analysis was used to assess interobserver variability between two radiologists.ResultsVolume reduction rates of leiomyomas after UAE ranged from 0.2%–89.1% (mean, 44.1%). ADC ranged from 0.559 × 10^?3 mm²/s to 1.814 × 10^?3 mm²/s (mean, 1.170 × 10^?3 mm²/s). ADC was statistically significantly related to volumetric response of leiomyomas (P = .014). Using a threshold of 1.092 × 10^?3 mm²/s, the sensitivity and specificity of ADC for prediction of > 50% volume reduction of the leiomyoma after UAE were 82.6% and 52.3%, respectively. Using a threshold of 1.023 × 10^?3 mm²/s, the sensitivity and specificity of ADC for prediction of < 30% volume reduction were 80.8% and 33.3%, respectively. The interclass correlation coefficient for measuring ADC of uterine leiomyomas between two radiologists was 0.98.ConclusionsADC of uterine leiomyomas was significantly related to the volume reduction after UAE. ADC may be useful in predicting the potential response to UAE. A high ADC of the uterine leiomyoma may be associated with a greater volume reduction after UAE.     

Percutaneous Closure Devices Do Not Reduce the Risk of Major Access Site Complications in Patients Undergoing Elective Carotid Stent Placement

PurposeTo examine the risk of femoral access site complications in patients undergoing carotid stent placement who were treated with a closure device compared with patients who were not treated with a closure device.Materials and MethodsA national, multihospital patient database, the Premier Perspective database, was used to identify patients hospitalized for carotid stent placement from 2006–2011. To reduce potential selection bias, a propensity score was generated for each patient using relevant clinical variables. Propensity score adjustment via 1:1 matching was performed on patients who did and did not receive a closure device. Primary outcomes were minor femoral access site complications and major complications requiring procedural intervention. Secondary outcomes included in-hospital mortality, stroke, and blood transfusion.ResultsAmong 12,287 patients who underwent carotid stent placement at 217 hospitals, 6,398 (52%) received a closure device on the day of the procedure. After propensity score matching, patients who received a closure device had a lower likelihood of minor access site complications (4.2% vs 5.4%; odds ratio = 0.77; 95% confidence interval, 0.55–0.93; P = .0071) compared with patients who did not receive a closure device; however, this difference was small and likely not clinically relevant. Both groups had a similar risk of major access site complications (P = .32), in-hospital mortality (P = .0520), and stroke (P = .31).ConclusionsUse of a closure device was not associated with a substantially reduced risk of major adverse events after carotid stent placement and was associated with only a small improvement in minor access site complications.     

Aortic Arch Vessel Geometries and Deformations in Patients with Thoracic Aortic Aneurysms and Dissections

PurposeTo quantify aortic arch geometry and in vivo cardiac-induced and respiratory-induced arch translations and arch branch angulations using three-dimensional geometric modeling techniques.Materials and MethodsScanning with electrocardiogram-gated computed tomography angiography during inspiratory and expiratory breath holds was performed in 15 patients (age, 64 y ± 14) with thoracic aortic aneurysms or dissections. From the lumen models, centerlines of the thoracic aorta, brachiocephalic artery, left common carotid artery, and left subclavian artery and their branching ostia positions were quantified. Three-dimensional translation of vessel ostia, branching angles, and their changes secondary to cardiac pulsation and respiration were computed.ResultsDuring expiration, all ostia translated rightward from systole to diastole (P < .035). Regardless of cardiac phase, all ostia translated posteriorly and superiorly from inspiration to expiration (P < .05). Respiration induced greater posterior and superior translations than cardiac pulsation (P < .03). The left common carotid artery branch angled significantly more toward the aortic arch compared with the brachiocephalic artery and left subclavian artery (P < .03). No significant changes in branching angle were found from systole to diastole or inspiration to expiration.ConclusionsIn patients with thoracic aortic aneurysms or dissections, the thoracic aortic arch translated significantly secondary to inspiration and expiration and to a lesser extent secondary to cardiac pulsation. Insignificant branching angle changes suggest that the aortic arch and its branch origins move predominantly in unison.     

Early Results from a United States Trial of Prostatic Artery Embolization in the Treatment of Benign Prostatic Hyperplasia

PurposeTo report early findings from a prospective United States clinical trial to evaluate the efficacy and safety of prostatic artery embolization (PAE) for benign prostatic hyperplasia (BPH).Materials and MethodsFrom January 2012 to March 2013, 72 patients were screened and 20 patients underwent treatment. Patients were evaluated at baseline and selected intervals (1, 3, and 6 mo) for the following efficacy variables: American Urological Association (AUA) symptom score, quality of life (QOL)–related symptoms, International Index of Erectile Function score, peak urine flow rate, and prostate volume (on magnetic resonance imaging at 6 mo). Complications were monitored and reported per Society of Interventional Radiology guidelines.ResultsEmbolization was technically successful in 18 of 20 patients (90%); bilateral PAE was successful in 18 of 19 (95%). Unsuccessful embolizations were secondary to atherosclerotic occlusion of prostatic arteries. Clinical success was seen in 95% of patients (19 of 20) at 1 month, with average AUA symptom score improvements of 10.8 points at 1 month (P < .0001), 12.1 points at 3 months (P = .0003), and 9.8 points at 6 months (P = .06). QOL improved at 1 month (1.9 points; P = .0002), 3 months (1.9 points; P = .003), and 6 months (2.6 points; P = .007). Sexual function improved by 34% at 1 month (P = .11), 5% at 3 months (P = .72), and 16% at 6 months (P = .19). Prostate volume at 6 months had decreased 18% (n = 5; P = .05). No minor or major complications were reported.ConclusionsEarly results from this clinical trial indicate that PAE offers a safe and efficacious treatment option for men with BPH.     

Microwave Ablation of Osteoid Osteomas Using Dynamic MR Imaging for Early Treatment Assessment: Preliminary Experience

PurposeTo evaluate the efficacy of microwave ablation for osteoid osteomas by using dynamic contrast-enhanced magnetic resonance (MR) imaging in early treatment assessment.Materials and MethodsTen patients (two female, eight male; mean age, 28 y; range, 16–47 y) presenting with osteoid osteomas were treated between June 2010 and December 2012 with the use of computed tomography (CT)–guided microwave ablation. Osteoid osteomas were found at the femoral neck (n = 4), tibia (n = 3), calcaneus (n = 1), navicular bone (n = 1), and dorsal rib (n = 1). Dynamic contrast-enhanced MR imaging at 3.0 T was performed 1 day before microwave ablation and again after ablation. The procedure was considered successful if the signal intensity (SI) of the lesion on MR imaging decreased by at least 50% and the patient was pain-free within 1 week of intervention.ResultsAll patients were pain-free within 1 week after microwave ablation and remained so during the 6 months of follow-up. No major or minor complications developed. On average, SI of the lesions decreased by 75% (range, 55.5%–89.1%) after treatment. The difference in lesion SI before versus after ablation was significant by t test (P < .0001; confidence interval, 120.26–174.96) and Wilcoxon test (P = .0020).ConclusionsMicrowave ablation treatment of osteoid osteoma was highly successful, without any complications observed. Dynamic contrast-enhanced MR imaging is a useful tool for diagnosing osteoid osteoma and evaluating treatment.     

Microwave Ablation of Pancreatic Head Cancer: Safety and Efficacy

PurposeTo evaluate the safety and efficacy of percutaneous microwave (MW) ablation treatment in locally advanced, nonresectable, nonmetastatic pancreatic head cancer.Materials and MethodsTen patients with pancreatic head cancer treated with percutaneous (n = 5) or laparotomic (n = 5) MW ablation were retrospectively reviewed. The MW generator used (45 W at 915 MHz) was connected by coaxial cable to 14-gauge straight MW antennas with a 3.7- or 2-cm radiating section. One or two antennae were used, with an ablation time of 10 minutes. Ultrasonographic (US) and combined US/cone-beam computed tomographic (CT) guidance were used in five patients each. Follow-up was performed by CT after 1, 3, 6, and, when possible, 12 months. Tumor response was assessed per Response Evaluation Criteria In Solid Tumors (version 1.1) and Choi criteria. The feasibility, safety, and major and minor complications associated with quality of life (QOL) were recorded prospectively.ResultsThe procedure was feasible in all patients (100%). One late major complication was observed in one patient, and no visceral injury was detected. No patient had further surgery, and all minor complications resolved during the hospital stay. An improvement in QOL was observed in all patients despite a tendency to return to preoperative levels in the months following the procedure, without the influence of minor complications. No repeat treatment was performed.ConclusionsDespite the small number of patients, the present results can be considered encouraging, showing that MW ablation is a feasible approach in the palliative treatment of pancreatic tumors.     

Polydioxanone Biodegradable Stent Placement in a Canine Urethral Model: Analysis of Inflammatory Reaction and Biodegradation

PurposeTo investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model.Materials and MethodsPDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction.ResultsStent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P < .001), the average thickness of papillary projection (0.80 mm vs 1.28 mm; P < .001), and the average thickness of submucosal fibrosis (0.34 mm vs 0.49 mm ; P < .001) were significantly increased in group B versus group A. There were no significant differences between group B and group C. The average inflammatory cell infiltration did not differ significantly in the three groups. Molecular weight losses were 54% in group A and 84% in group B. In group C, PDO stents were completely decomposed.ConclusionsAn experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks.     

Percutaneous Microwave Ablation of Hepatic Tumors: Prospective Evaluation of Postablation Syndrome and Postprocedural Pain

PurposeTo prospectively investigate the frequency and severity of postablation syndrome (PAS) and postprocedural pain in a cohort of patients undergoing hepatic microwave ablation.Materials and MethodsFrom March 2009 to November 2011, 54 consecutive patients undergoing microwave ablation for liver tumors were enrolled. A questionnaire was administered to investigate PAS and pain at 1, 7, and 40 days after ablation. Four patients did not complete all three questionnaires and were excluded from the analysis. Additionally, laboratory tests with results known to significantly increase or decrease after ablation were performed, and ablation parameters were recorded. Potential predictors of PAS and pain at 1 and 7 days were evaluated by a logistic regression model.ResultsFifty patients underwent a single microwave ablation session, 33 for hepatocellular carcinoma (HCC) and 17 for liver metastasis. Median ablation volumes on computed tomography were 31 cm³ for HCC and 42 cm³ for metastasis. Sixty percent of patients experienced PAS in the first week. Aspartate aminotransferase (AST) levels after ablation were significantly associated with PAS during postprocedure days 1–7. Median visual analog scale scores for pain at the puncture site were 1 and 0.24 at 1 and 7 days, respectively. The risk of having at least moderate pain in the first week was significantly related to ablation volume and time and postablation increase in AST level.ConclusionsThe incidence and severity of PAS with hepatic microwave ablation is similar to that reported for radiofrequency ablation, with the best predictive factor being postablation AST level elevation. Postablation pain was best predicted by total ablation volume and AST level.     

Chemoembolization via the Left Internal Mammary Artery Supplying Hepatocellular Carcinoma

PurposeTo present radiologic findings that show favorable tumor response after chemoembolization via the left internal mammary artery (LIMA).Materials and MethodsBetween October 2002 and April 2013, 57 patients with hepatocellular carcinoma (HCC) underwent 69 sessions of chemoembolization via the LIMA. Imaging findings including tumor size, location, and visibility of tumor-feeding artery on cross-sectional images were retrospectively reviewed in consensus by two radiologists. Tumor response after chemoembolization via the LIMA was assessed by the modified Response Evaluation Criteria in Solid Tumors on follow-up multidetector computed tomography in consensus.ResultsThe mean tumor size supplied by the LIMA was 6.8 cm (range, 1.0–21.0 cm). HCCs supplied by the LIMA tended to be located in the subcapsular area including exophytic features (57 of 57; 100%) and were more likely to be located in the left lobe of the liver (56 of 57; 98%). HCCs supplied by the LIMA were more likely to be multiple or infiltrative (52 of 57; 91%) and marginally recurred (43 of 57; 75%). Feeding arteries of the LIMA were identified in a high percentage of cases (49 of 66; 74%) on cross-sectional images obtained before embolization. Regarding tumor response, tumors that were newly developed or exclusively supplied by the LIMA showed better target tumor response (P = .011 and P < .0001, respectively). On multivariate analysis, tumors exclusively supplied by the LIMA showed significantly better target tumor response with odds ratio of 16.32.ConclusionsChemoembolization via the LIMA has a favorable target tumor response when HCCs are exclusively supplied by the LIMA.     

Inferior Vena Cava Filter Retrieval: Effectiveness and Complications of Routine and Advanced Techniques

PurposeTo investigate the success and safety of routine versus advanced inferior vena cava (IVC) filter retrieval techniques.Materials and MethodsA retrospective review was performed of patients who underwent IVC filter placement and/or a retrieval attempt over a 10-year period. Retrieval technique(s), preretrieval computed tomography, preretrieval venography, and clinical/imaging follow-up for 30 days after retrieval were analyzed. Mean filter dwell time was 134 days (range, 0–2,475 d).ResultsFilter retrieval was attempted 231 times in 217 patients (39% female, 61% male; mean age, 50.7 y), with success rates of 73.2% (169 of 231) and 94.7% (54 of 57) for routine and advanced filter retrieval techniques, respectively. The overall filter retrieval complication rate was 1.7% (four of 231); complications in four patients (with multiple complications in some cases) included IVC dissection, IVC intussusception, IVC thrombus/stenosis, filter fracture with embedded strut, IVC injury with hemorrhage, and vascular injury from complicated venous access. The rate of complications associated with filter retrievals that required advanced technique was significantly higher than seen with routine technique (5.3% vs 0.4%; P < .05). Longer dwell time, more transverse tilt, and presence of an embedded hook were associated with significantly increased rates of failed retrieval via routine technique (P < .05).ConclusionsIVC filters can be retrieved with a high overall success rate (98.2%) and a low complication rate (1.7%) by using advanced techniques when the routine approach has failed; however, the use of advanced techniques is associated with a significantly higher complication rate.     

Prospective Evaluation of Optical Coherence Tomography in Lower Limb Arteries Compared with Intravascular Ultrasound

PurposeTo compare in a prospective noninferiority study optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in popliteal and infrapopliteal vessels.Materials and MethodsOCT and IVUS images of 112 popliteal and infrapopliteal arterial segments were prospectively obtained from 16 patients with peripheral arterial occlusive disease. Three observers evaluated the corresponding OCT and IVUS images for image quality, artifact frequency, discriminability of vessel wall layers, and plaque composition. Measurements of the lumen, vessel, and plaque areas were compared for both modalities.ResultsThe intrareader and interreader reproducibility of plaque tissue discrimination (0.88 vs 0.75), overall image quality, and vessel wall layer discriminability were significantly higher for OCT (all P < .001). Artifact frequency was higher in OCT, constraining the imaging of the tibioperoneal trunk. The results of measurements of the lumen and vessel area were comparable for both modalities (correlation > 0.9, P < .001). Plaque area measurements differed (correlation 0.8, P < .01) because OCT underestimated it. The OCT procedure caused vessel spasms in two patients.ConclusionsOCT imaging of infrapopliteal arteries is feasible and safe and provides high image quality. It enables an accurate assessment of vessel lumen, wall, and plaque. Compared with IVUS, OCT images provide excellent image quality and superior visualization of vessel wall layers and different plaque components. The penetration depth of OCT restricts its use to suitable vessel regions.     

Factors Associated with Patency Following Angioplasty of Hemodialysis Fistulae

PurposePatency after percutaneous transluminal angioplasty of native hemodialysis arteriovenous fistulae (AVFs) is highly variable. This study aimed to identify predictors of patency following angioplasty in native AVFs.Materials and MethodsAll endovascular procedures performed in native AVFs between 2005 and 2013 at two institutions were retrospectively reviewed. Clinical, anatomic, biochemical, and medication variables were subjected to univariate and multivariate Cox regression analysis to identify predictors of postintervention primary and secondary patency.ResultsDuring the study period, 207 patients underwent first angioplasty of their AVF. Follow-up ranged from 14 days to 8 years, during which another 247 endovascular interventions were performed to maintain patency. Postintervention primary patency rates at 6, 12, and 24 months were 66%, 49%, and 29%, respectively. Postintervention secondary patency rates at 6, 12, and 24 months were 94%, 84%, and 79%, respectively. On multivariate adjusted Cox regression analysis, upper-arm AVFs (P = .00072), AVFs less than 6 months of age (P = .0014), presence of multiple stenoses (P = .019), and degree of initial stenosis (P = .016) were significantly associated with shorter postintervention primary patency. A previously failed AVF was the only significant predictor of postintervention secondary patency loss (P = .0053).ConclusionsAnatomic factors related to the AVF location, AVF age, and the extent of the lesion are important predictors of restenosis after balloon angioplasty. Traditional cardiovascular risk factors, metabolic and inflammatory markers, and medications were not associated with postintervention patency.