Contemporary Systematic Review and Meta-Analysis of Early Outcomes with Percutaneous Treatment for Infrapopliteal Atherosclerotic Disease

PurposeThe need for specialty devices to improve the technical outcome of endovascular interventions is dependent on the rate of early failure in such procedures. This meta-analysis assessed procedural outcomes of such interventions to elucidate the rate of early procedural failures and the need for such specialty devices.Materials and MethodsMEDLINE and EMBASE were searched for contemporary studies (2000–2012) reporting procedural or short-term outcomes for revascularization of infrapopliteal atherosclerotic lesions. A random-effects metaanalysis was performed, which included post hoc comparisons among treatment groups.ResultsA total of 42 studies with 52 treatment arms representing 3,660 unique patients were included. Technical success rates were higher with bare metal stents (BMSs; 98.6%) than with atherectomy (92.2%; P < .05) or percutaneous transluminal angioplasty (PTA; 91.2%; P = .01), and higher with drug-eluting stents (DESs) than with PTA (P < .001). DES use had higher primary patency rates than atherectomy (P < .05), BMS use (P < .001), and PTA (P < .01). The 30-day rate of target lesion revascularization was significantly higher with PTA (8.1%) than with BMSs (2.2%; P < .05) and DESs (1.1%; P < .05). Thirty-day rates of major unplanned amputation (range, 1.5%–4.4%) and mortality (range, 0.9%–3.3%) were comparable among treatment groups. Significant heterogeneity among studies was noted for most PTA outcomes. Publication bias was evident for most PTA and DES outcomes.ConclusionsEarly failure of percutaneous therapies in patients with infrapopliteal atherosclerotic lesions is device- and technique-dependent. Specialty devices designed to reduce technical failure rates may therefore be of benefit in this selected group of patients. Study results are confounded by inconsistent data reporting, heterogeneity of treatment effects, and publication bias.     

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.     

Cone-Beam CT Hepatic Arteriography in Chemoembolization for Hepatocellular Carcinoma: Angiographic Image Quality and Its Determining Factors

PurposeTo analyze image quality and the factors that determine it for cone-beam computed tomography (CT) hepatic arteriography in chemoembolization for hepatocellular carcinoma (HCC).Materials and MethodsFrom September 2009–December 2010, 399 consecutive patients referred for chemoembolization of HCC were scheduled for cone-beam CT scan. There were 12 patients (3%) excluded because of difficulty with breath-hold. Of the 387 patients who underwent cone-beam CT hepatic arteriography, 100 patients were ultimately included in the study according to inclusion criteria. Maximum intensity projection images were scored for image quality of each segmental hepatic artery. Potential determining factors for image quality were diaphragmatic motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio. The flow rate of contrast media, x-ray delay, and location of the catheter tip were also evaluated.ResultsIt was possible to trace at least subsegmental hepatic arteries in 625 of 700 segments (89.3%) on cone-beam CT hepatic arteriography. Diaphragmatic motion, prominent portal vein enhancement, and low hepatic artery-to-parenchyma enhancement ratio worsened image quality (P < .001, P = .022, and P = .017). Owing to cardiac motion artifacts, image quality of the left lateral segments (S2 and S3) was poorer compared with the remaining hepatic segments (S4–S8).ConclusionsIn most cases, the quality of cone-beam CT hepatic arteriography images was good enough to trace subsegmental hepatic arteries at a minimum. Respiratory and cardiac motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio significantly affected the image quality of cone-beam CT hepatic arteriography.     

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.     

Clinical Impact of Sacroplasty on Patient Mobility

PurposeTo evaluate the effect of sacroplasty on patient mobility and pain when performed as a treatment for sacral insufficiency fractures.Materials and MethodsImaging with computed tomography (CT), magnetic resonance imaging, or bone scan confirmed the diagnosis of sacral insufficiency fractures. Baseline clinical mobility scale (CMS) score and visual analog scale (VAS) pain score were recorded. Sacroplasty was performed under CT guidance. Follow-up CMS and VAS scores were assessed at 4, 24, and 48 weeks.ResultsEighteen elderly patients (age 80 y ± 8.5; 17 women) were treated. Repeated-measures analysis of variance was conducted to assess changes in CMS and VAS scores over time. Pairwise comparisons revealed a significant increase in average CMS score between baseline and all three follow-up points—4 weeks (P < .001), 24 weeks (P < .001), and 48 weeks (P < .001)—indicating improvement in mobility over time. Pairwise comparisons revealed significant differences in mean VAS scores between baseline and all three follow-up time points—4 weeks (P < .001), 24 weeks (P < .001), and 48 weeks (P < .001)—indicating improvement in overall pain level over time.ConclusionsTreatment with CT-guided sacroplasty for sacral insufficiency fractures in this elderly population resulted in significant improvement in patient mobility.     

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.     

Combination Radiofrequency Ablation and Percutaneous Osteoplasty for Palliative Treatment of Painful Extraspinal Bone Metastasis: A Single-Center Experience

PurposeTo evaluate combined radiofrequency (RF) ablation and percutaneous osteoplasty (POP) in patients with painful extraspinal bone metastases.Materials and MethodsIn a retrospective study, 38 patients with 54 extraspinal bone metastases (ilium, n = 24; acetabulum, n = 21; femur, n = 7; ischium, n = 1; tibia, n = 1) were treated with RF ablation and POP. All patients had pain refractory to analgesic medication with intensity > 3 on a visual analog scale (VAS). Changes in quality of life were evaluated based on pain relief (VAS score), function on a Karnofsky performance scale, and analgesic dose before and immediately after the procedure and during follow-up. VAS score was the primary outcome, and the others were secondary outcomes.ResultsTechnical success was achieved in 37 patients (97.4%). Mean VAS score declined significantly from 7.1 ± 1.5 before treatment to 2.2 ± 2.0 at 24 hours after treatment (P < .05), 1.6 ± 1.8 at 3 months after treatment (P < .05), and 1.3 ± 1.8 at 6 months after treatment (P < .05). Pain relief immediately after the procedure was reported by 35 patients (92.1%); pain regressed completely in 7 (18.4%) patients. After 6 months, narcotic analgesia had been suspended in 32 of 33 patients (97.0%). Pain was controlled by nonsteroidal antiinflammatory drugs in 8 patients (24.2%), and no analgesia was necessary in 24 patients (72.7%). Mean Karnofsky performance scale score after treatment was higher than before treatment (P < .05). The major complication rate was 2.6% (1 of 38 patients), with one case of vasovagal shock. The minor complication rate was 23.7% (9 of 38 patients).ConclusionsRF ablation with POP is effective for pain relief and functional recovery in patients with painful extraspinal bone metastases and can significantly improve quality of life.     

Optimized energy of spectral coronary CT angiography for coronary plaque detection and quantification

BackgroundTo optimize spectral coronary computed tomography angiography (CTA) for quantification of coronary artery plaque components.Materials and methodsFifty-one subjects were prospectively enrolled (88.2% male) (NCT02740699). Dual energy coronary CTA was performed at 90/Sn150 kVp using a 3rd generation dual-source CT scanner (SOMATOM Force, Siemens Healthcare). Dual energy images were reconstructed with a) linear mixed blending of 90 and Sn150 kVp data, b) virtual monoenergetic algorithm from 40 to 150 keV (at 10- keV intervals), and c) noise-optimized virtual monoenergetic algorithm from 40 to 150 keV. Image noise, iodine signal-to-noise-ratio (SNR), and contrast-to-noise ratio (CNR) for calcified and non-calcified plaque were measured. Qualitative readings of image quality were performed. Semi-automated software (QAngioCT, Medis) was used to quantify coronary plaque. Linear mixed-models that account for within-subject correlation of plaques were used to compare the results.Results100–150 keV noise-optimized virtual monoenergetic images had lower image noise than linear mixed images (all P < 0.05). The highest iodine SNR was achieved in 40 keV noise-optimized virtual monoenergetic images (33.3 ± 0.6 vs 23.3 ± 0.7 for linear mixed images, P < 0.001). 40–70 keV noise-optimized virtual monoenergetic images and 70 keV virtual monoenergetic images had superior coronary plaque CNR versus linear mixed images (all P < 0.01) with a maximum improvement of 20.1% and 22.7% for calcified plaque and non-calcified plaque (38.8 ± 2.2 vs 32.3 ± 2.3 and 17.3 ± 1.3 vs 14.1 ± 1.4, respectively). Using 90/Sn150 kVp linear mixed images as a reference, the plaque quantity was similar for 70 keV noise-optimized virtual monoenergetic images whereas low keV images (e.g. 40 keV) yielded significantly higher coronary plaque volumes (all P < 0.001).ConclusionSpectral coronary CTA with low energy (40–70 keV) post-processing can improve the CNR of coronary plaque components. However, low energies (such as 40 keV) resulted in different absolute volumes of coronary plaque compared to “conventional” mixed 90/Sn150 kVp images.     

Technical Details and Clinical Outcomes of Transpopliteal Venous Stent Placement for Postthrombotic Chronic Total Occlusion of the Iliofemoral Vein

PurposeTo evaluate the technical aspects and early clinical results of stent placement for managing postthrombotic chronic total occlusion (CTO) of the iliofemoral vein through ipsilateral popliteal access.Materials and MethodsA retrospective analysis of 110 patients (44 men; mean age, 51 y; 118 limbs; 102 left limbs) with postthrombotic CTO of the iliofemoral vein treated with stent placement in a single institution from January 2007–December 2011 was conducted. All occlusions were initially accessed via ipsilateral popliteal veins under the guidance of venography or ultrasonography. Technical aspects, quality of life, stent patency, and Villalta scores were recorded at follow-up evaluation. Risk factors of in-stent restenosis and early in-stent thrombosis were evaluated using Cox proportional hazards regression model.ResultsPercutaneous recanalization was successful in 112 of 118 limbs (95%). The mean duration of the procedure was 43 minutes (range, 10–120 min). The quality of life and Villalta scores were significantly improved (P < .01). The 3-year primary, assisted primary, and secondary cumulative stent patency rates were 70%, 90%, and 94%. During a median follow-up period of 25 months (range, 1–52 mo), the relief rates of severe leg pain (visual analog scale > 5) and severe leg swelling (grade 3) were 72% (49 of 68) and 70% (64 of 91), respectively, and the healing of ulcers was successful in 78% (36 of 46) of the cases. After stent placement, the limbs with visible remaining collateral circulation had a higher rate of early in-stent thrombosis (22.5% vs 6.1%; P = .007). The patients with long stents extending below the inguinal ligament had a higher rate of in-stent restenosis (hazard ratio = 1.77–6.5; P = .0146).ConclusionsTranspopliteal venous stent placement is an effective, safe, and feasible method of managing postthrombotic CTO of the iliofemoral vein. The stent extending below the inguinal ligament is the major risk factor of in-stent restenosis. The visible remaining collateral circulation after stent placement may indicate persistent hemodynamically significant stenosis.     

Prospective,Randomized Study of Coil Embolization versus Surefire Infusion System during Yttrium-90 Radioembolization with Resin Microspheres

PurposeTo compare standard coil embolization versus the use of an antireflux microcatheter (ARM) in patients undergoing planning angiography before selective internal radiation therapy (SIRT).Materials and MethodsA prospective, single-center trial was performed in which 30 patients were randomly assigned to undergo SIRT with coil embolization or the use of an ARM. The coil group underwent detachable coil embolization of nontarget vessels, and the ARM group underwent infusion of macroaggregated albumin with use of an ARM system, without coil embolization. Single-photon emission computed tomography (CT)/CT was then performed to assess for nontarget distribution. The primary endpoint was fluoroscopy time during planning angiography. Secondary endpoints included deployment time, total procedure time, radiation dose–area product, contrast agent used, and adverse events. Endpoints were evaluated during planning angiography and SIRT.ResultsOver a 9-month period, 30 consecutive patients were randomized at a 1:1 ratio between coil embolization and ARM groups. Technical success rates were 100% in both groups. Mean fluoroscopy time was significantly reduced in the ARM group versus the coil embolization group (1.8 min [range, 0.4–4.9 min] vs 6.0 min [range, 1.9–15.7 min]; P = .002). The planning procedure time (P < .001), deployment time (P < .001), dose–area product (P = .04), and amount of contrast agent used (P < .001) were also significantly less in the ARM group than in the coil embolization group. No nontarget distribution was detected in either group. There was no difference between groups in dose delivered on the day of SIRT (P = .71). There were no major or minor adverse events at 30 days.ConclusionsThe use of an ARM during planning angiography can significantly reduce fluoroscopy time, procedure time, and radiation dose.     

A pilot study to determine the effect of radiographer training on radiostereometric analysis imaging technique

IntroductionProducing x-ray images for radiostereometric analysis (RSA) is a demanding technique. Suboptimal examinations result in a high percentage of exposure repetition. The aim of this pilot study was to use an experiential training approach to sharpen the skills of radiographers in acquiring images of an optimal quality.MethodsA controlled trial using action research strategy was used. The study entailed a two phased approach. Radiographers were purposefully recruited and trained to perform the required investigations. Each phase included 12 examinations of a total knee arthroplasty phantom followed by 10 patient examinations. The quality of all x-ray images performed during the two phases was characterized by measuring the number of visible beads, the center position of the prosthesis (CP) compared to the center of calibration field (CCF). The number of re-exposures used to obtain a usable image during patient examinations was also recorded.ResultsThe radiographers undergoing the training resulted in a significant improvement in the quality of images produced and visualization of the beads. That is, the ability to move the CP on average 36.1 mm closer to the CCF (p < 0.001), the number of visible beads increased by 3.1 (p < 0.001) and radiographers needed 2.1–2.9 exposures less to obtain RSA images of sufficient qualities during patient examinations in phase 2 (p < 0.001).ConclusionThis study illustrates the value of experiential method of teaching and learning with minimal compromise on patient safety but a significant contribution in terms of establishing quality of RSA images.     

Respiration-induced Deformations of the Superior Mesenteric and Renal Arteries in Patients with Abdominal Aortic Aneurysms

PurposeTo quantify respiration-induced deformations of the superior mesenteric artery (SMA), left renal artery (LRA), and right renal artery (RRA) in patients with small abdominal aortic aneurysms (AAAs).Materials and MethodsSixteen men with AAAs (age 73 y ± 7) were imaged with contrast-enhanced magnetic resonance angiography during inspiratory and expiratory breath-holds. Centerline paths of the aorta and visceral arteries were acquired by geometric modeling and segmentation techniques. Vessel translations and changes in branching angle and curvature resulting from respiration were computed from centerline paths.ResultsWith expiration, the SMA, LRA, and RRA bifurcation points translated superiorly by 12.4 mm ± 9.5, 14.5 mm ± 8.8, and 12.7 mm ± 6.4 (P < .001), and posteriorly by 2.2 mm ± 2.7, 4.9 mm ± 4.2, and 5.6 mm ± 3.9 (P < .05), respectively, and the SMA translated rightward by 3.9 mm ± 4.9 (P < .01). With expiration, the SMA, LRA, and RRA angled upward by 9.7° ± 6.4, 7.5° ± 7.8, and 4.9° ± 5.3, respectively (P < .005). With expiration, mean curvature increased by 0.02 mm^?1 ± 0.01, 0.01 mm^?1 ± 0.01, and 0.01 mm^?1 ± 0.01 in the SMA, LRA, and RRA, respectively (P < .05). For inspiration and expiration, RRA curvature was greater than in other vessels (P < .025).ConclusionsWith expiration, the SMA, LRA, and RRA translated superiorly and posteriorly as a result of diaphragmatic motion, inducing upward angling of vessel branches and increased curvature. In addition, the SMA exhibited rightward translation with expiration. The RRA was significantly more tortuous, but deformed less than the other vessels during respiration.     

Serum MicroRNA-210 as a Predictive Biomarker for Treatment Response and Prognosis in Patients with Hepatocellular Carcinoma undergoing Transarterial Chemoembolization

PurposeTo investigate whether serum microRNA-210 (miR-210) level can serve as an indicator of prognosis and a predictor of efficacy of transarterial chemoembolization in patients with hepatocellular carcinoma (HCC).Materials and MethodsSerum miR-210 level was measured in 113 patients with HCC before transarterial chemoembolization (t1), 3 days after transarterial chemoembolization (t2), and 4 weeks after transarterial chemoembolization (t3) and compared with 39 healthy control subjects. The correlations between miR-210 levels and clinicopathologic factors, tumor responsiveness, and prognosis were analyzed. The modified Response Evaluation Criteria in Solid Tumors assessment was conducted at t3.ResultsA higher mean baseline miR-210 level was observed in patients with HCC compared with control subjects (3.69 ± 2.04 vs 1.08 ± 0.45, P < .001). A positive correlation between baseline miR-210 level and tumor size (P < .001), vascular invasion (P = .005), tumor differentiation (P = .037), and Barcelona Clinic Liver Cancer stage (P < .001) was observed. Elevated baseline miR-210 level also served as an independent prognostic factor predicting poor overall survival (risk ratio, 2.082; P = .003). Patients who did not respond to transarterial chemoembolization had higher baseline miR-210 levels than patients who did respond to treatment (4.34 ± 1.67 vs 3.28 ± 2.15, P < .001). In addition, miR-210 levels increased significantly 4 weeks after transarterial chemoembolization in nonresponders (5.79 ± 2.06 at t3 vs 4.34 ± 1.67 at t1, P < .001), whereas no significant change was observed in responders (3.53 ± 2.20 at t3 vs 3.28 ± 2.15 at t1, P = .116). Lastly, an inverse correlation was identified between miR-210 change t1–t3 with the time to radiologic progression (P < .001).ConclusionsSerum miR-210 may represent a novel biomarker for predicting efficacy of transarterial chemoembolization and overall survival for patients with HCC.     

Comparison of Characteristics and Transarterial Chemoembolization Outcomes in Patients with Unresectable Hepatocellular Carcinoma and Different Viral Etiologies

PurposeTo determine any differences in patient characteristics and outcomes after transarterial chemoembolization between different viral etiologies of hepatocellular carcinoma (HCC).MethodsThis retrospective study consisted of 201 patients undergoing first-time transarterial chemoembolization for unresectable HCC from January to December 2009. The patients were divided into four groups: hepatitis B virus (HBV) only (n = 104), hepatitis C virus (HCV) only (n = 63), HBV and HCV (n = 10), and no viral hepatitis (n = 24). The clinical and laboratory data were obtained from electronic medical records, and imaging findings obtained before transarterial chemoembolization were analyzed. Kaplan-Meier analyses were used to assess the impact of HBV or HCV status, clinical characteristics, and imaging results on overall survival.ResultsAfter a median follow-up of 28.3 months ± 16.2, the 1-, 2-, and 3-year overall survival rates were 74.1%, 59.7%, and 53.2%. Patients with HBV had a significant association with younger age (P = .001), higher male-to-female ratio (P = .003), lower alanine aminotransferase levels (P = .018), higher albumin levels (P = .009), and multifocal tumors at diagnosis (P = .04) compared with patients with HCV. Patients with both HBV and HCV had significantly higher serum bilirubin levels compared with the other groups (P = .002). No significant difference was found in overall survival among the different hepatitis groups (P = .943). Multivariate analysis showed that statistically significant determinants for overall survival were Child-Pugh class (P = .002), Barcelona Clinic Liver Cancer stage (P < .001), tumor size (P < .001), and distribution (P < .001).ConclusionsViral etiology has no correlation with the outcome of patients with HCC undergoing transarterial chemoembolization.     

Microwave Thermal Ablation of Spinal Metastatic Bone Tumors

PurposeTo assess feasibility, safety, and efficacy of microwave ablation of spinal metastatic bone tumors.Materials and MethodsRetrospective study of 17 patients with 20 spinal metastatic tumors treated with microwave ablation under computed tomographic guidance between March 2011 and August 2013 was performed. Ablations were performed under local anesthesia and nitrous oxide ventilation. Lesions were lumbar (n = 10), sacral (n = 7), and thoracic (n = 3) in location. Primary neoplastic sites were lung (n = 9), prostate (n = 4), kidney (n = 6), and uterus (n = 1). Adjunct cementoplasty was performed in nine cases, and a temperature-monitoring device was used in four cases. Procedure effectiveness was evaluated by visual analog scale (VAS) during a 6-month follow-up. Patient medical records were reviewed, and demographic and clinical data, tumor characteristics, and information on pain were assessed.ResultsMean ablation time was 4.4 minutes ± 2.7 (range, 1–8 min), with an average of 3.8 cycles per ablation at 60 W (range, 30–70 W). The preprocedure mean VAS score was 7.4 ± 1.2 (range, 6–9). Pain relief was achieved in all but one patient. Follow-up VAS scores were as follows: day 0, 1.3 ± 1.8 (P < .001); day 7, 1.6 ± 1.7 (P < .001); month 1, 1.9 ± 1.6 (P < .001); month 3, 2.2 ± 1.5 (P < .001); and month 6, 2.3 ± 1.4 (P < .01). No complications were noted.ConclusionsMicrowave ablation appears to be feasible, safe, and an effective treatment of painful refractory spinal metastases and may be considered as a potential alternative percutaneous technique in the management of spinal metastases.     

Morphologic Outcome after Endovascular Treatment of Complicated Type B Aortic Dissection

PurposeTo investigate the long-term morphologic changes of the aorta after thoracic endovascular aortic repair (TEVAR) for acute complicated type B aortic dissection and to analyze whether these changes differed between DeBakey class IIIa and IIIb dissections.Materials and MethodsDuring the period 1999–2009, 58 patients with acute complicated type B aortic dissection were treated with TEVAR. Seven patients lacked follow-up data, leaving 51 patients—17 patients with DeBakey IIIa aortic dissection and 34 patients with DeBakey IIIa aortic dissection IIIb—for inclusion in the study. Computed tomography scans performed before and after TEVAR were evaluated. Maximum thoracic and abdominal aortic diameters and diameters of the true lumen and false lumen at the level of the maximum aortic diameter in the thorax and abdomen were analyzed as well as degree of thrombosis of the false lumen.ResultsThere was an overall significant reduction of the thoracic aortic diameter, increased true lumen diameter, and reduced false lumen diameter (P < .05). Total thrombosis of the false lumen, with or without reintervention, was seen in 53% of all patients, in 41% primarily and in 12% after reintervention. The IIIa group had a higher degree of total false lumen thrombosis. All patients in the IIIb group had total thrombosis of the false lumen along the stent graft.ConclusionsLong-term follow-up showed favorable aortic remodeling after TEVAR for acute complicated type B aortic dissection. Total thrombosis of the false lumen occurred more often in patients with DeBakey IIIa aortic dissection compared with patients with DeBakey IIIb aortic dissection.     

Ultrasound-Accelerated versus Standard Catheter-Directed Thrombolysis in 102 Patients with Acute and Subacute Limb Ischemia

PurposeTo compare the safety and efficacy of ultrasound-accelerated thrombolysis (UAT) and standard catheter-directed thrombolysis (CDT) in patients with acute and subacute limb ischemia.Materials and MethodsMedical records of all patients treated with thrombolysis for acute and subacute limb ischemia between August 2005 and January 2012 were reviewed. Coprimary (increase in ankle-brachial index, degree of lysis) and secondary endpoints (technical success, distal embolization, bleeding complications, need for additional interventions) were assessed. UAT was performed in 75 patients, and CDT was performed in 27 patients. Patients’ baseline demographic and clinical parameters and procedure details, including lytic drug infusion rate (P = .704 and P = .987), total infusion time (P = .787 and P = .377), and use of adjunctive procedures (P = .457), did not differ significantly between the two groups.ResultsComplete lysis was achieved in 72.0% (UAT) and 63.0% (CDT) of patients (P = .542); hemodynamic success was achieved in 91.8% (UAT) and 92.3% (CDT) (P = .956). Overall major and minor bleeding complications were observed in 6.9% (UAT) and 3.9% (CDT) of patients. Major (P = .075) and minor (P = .276) bleeding independently did not differ between UAT and CDT. Major and minor bleeding combined was lower: 6.7% (UAT) versus 22.2% (CDT) (P = .025). Overall target vessel patency after 8.0 months (range, 1.5–20.5 mo) was 73.5%; target vessel patency for UAT was 75.9% versus 64.3% for CDT (P = .379). Median long-term survival was not significantly different between UAT and CDT: 3.6 years (range, 2.42–5.33 y) versus 1.8 years (range, 1.33–4.92 y) (P = .061).ConclusionsBoth UAT and CDT are safe and efficient treatment modalities for patients with acute and subacute limb ischemia. The observed lower risk of total bleeding for UAT versus CDT may warrant prospective comparative trials.     

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.     

Chest Radiograph–based Algorithm for Managing Malfunctioning Ports

PurposeTo evaluate a chest x-ray–based algorithm for managing malfunctioning ports.Materials and MethodsA review of interventional radiology procedures on malfunctioning ports during the period 2000–2012 was performed. Events were divided into two periods: before and after implementation of an algorithm beginning with tip position evaluation using a chest x-ray. Time to return to usability, frequency of interventions to restore function, and frequency of malfunctioning ports remaining in use after the procedure were calculated.ResultsThe review included 303 procedures before implementation of the algorithm on 237 access sites in 227 patients (mean age, 56 y; 38% male) and 155 procedures after implementation of the algorithm on 131 access sites in 130 patients (mean age, 55 y; 35% male). Implementation of the algorithm was associated with significantly fewer repeat checks on the same access (27% before algorithm, 9% after algorithm, P < .001) and reduced frequency of a malfunctioning port remaining in use after the interventional radiology procedure (43% before algorithm to 14% after algorithm, P < .001). Median time from consultation to revision was significantly less after implementing the algorithm (13 days before algorithm, 1 day after algorithm, P < .001). Median time from consultation to port usability was also less after implementing the algorithm (2.7 days before algorithm, 1 day after algorithm, P < .001).ConclusionsImplementation of the algorithm was associated with significantly less frequent repeat procedures on the same port and a lower frequency of malfunctioning ports remaining in place. Use of the algorithm was associated with significantly reduced time from consultation to revision and to return to usability. These findings suggest the algorithm allows triage of patients with malfunctioning ports to the appropriate intervention before undergoing a procedure.     

Quantitative Assessment of Lipiodol Deposition after Chemoembolization: Comparison between Cone-Beam CT and Multidetector CT

PurposeTo evaluate the ability of cone-beam computed tomography (CBCT) performed directly after transarterial chemoembolization to assess ethiodized oil (Lipiodol) deposition in hepatocellular carcinoma (HCC) and compare it with unenhanced multidetector computed tomography (CT).Materials and MethodsConventional transarterial chemoembolization was used to treat 15 patients with HCC, and CBCT was performed to assess Lipiodol deposition directly after transarterial chemoembolization. Unenhanced multidetector CT was performed 24 hours after transarterial chemoembolization. Four patients were excluded because the margin of tumor or area of Lipiodol deposition was unclear. The image enhancement density of the entire tumor and liver parenchyma was measured by ImageJ software, and tumor-to-liver contrast (TLC) was calculated. In addition, volumetric measurement of tumor and Lipiodol was performed by semiautomatic three-dimensional volume segmentation and compared using linear regression to evaluate consistency between the two imaging modalities.ResultsThe mean value of TLC on CBCT was not significantly different from TLC on multidetector CT (337.7 HU ± 233.5 vs 283.0 HU ± 152.1, P = .103).The average volume of the whole tumor and of only the regions with Lipiodol deposition and the calculated average percentage of Lipiodol retention on CBCT were not significantly different compared with multidetector CT (tumor volume, 9.6 cm³ ± 11.8 vs 10.8 cm³ ± 14.2, P = .142; Lipiodol volume, 6.3 cm³ ± 7.7 vs 7.0 cm³ ± 8.1, P = .214; percentage of Lipiodol retention, 68.9% ± 24.0% vs 72.2% ± 23.1%, P = .578). Additionally, there was a high correlation in the volume of tumor and Lipiodol between CBCT and multidetector CT (R² = 0.919 and 0.903).ConclusionsThe quantitative image enhancement and volume analyses demonstrate that CBCT is similar to multidetector CT in assessing Lipiodol deposition in HCC after transarterial chemoembolization.