Becoming a thrombectomy-capable stroke center: Clinical and medico-economical effectiveness at the hospital level.

INTRODUCTION: Too few patients benefit from endovascular therapy (EVT) in large vessel occlusion acute stroke (LVOS), and various acute stroke care paradigms are currently investigated to reduce these inequalities in health access. We aimed to investigate whether newly set-up thrombectomy-capable stroke centers (TSC) offered a safe, effective and cost-effective procedure. PATIENTS AND METHODS: This French retrospective study compared the outcomes of LVOS patients with an indication for EVT and treated at the Perpignan hospital before on-site thrombectomy was available (Primary stroke center), and after formation of local radiology team for neurointervention (TSC). Primary endpoints were 3-months functional outcomes, assessed by the modified Rankin scale. Various safety endpoints for ischemic and hemorragic procedural complications were assessed. We conducted a medico-economic analysis to estimate the cost-benefit of becoming a TSC for the hospital. RESULTS: The differences between 422 patients in the PSC and 266 in the TSC were adjusted by the means of weighted logistic regression. Patients treated in the TSC had higher odds of excellent functional outcome (aOR 1.77 [1.16-2.72], p = 0.008), with no significant differences in the rates of procedural complications. The TSC setting shortened onset-to-reperfusion times by 144 min (95% CI [131-155]; p < 0.0001), and was cost-effective after 21 treated LVOS patients. On-site thrombectomy saves 10.825€ per patient for the hospital. DISCUSSION: Our results demonstrate that the TSC setting improves functional outcomes and reduces intra-hospital costs in LVOS patients. TSCs could play a major public health role in acute stroke care and access to EVT.

Usefulness of a single-parameter tool for the prediction of large vessel occlusion in acute stroke.

BACKGROUND: In acute stroke, large vessel occlusion (LVO) should be promptly identified to guide patient's transportation directly to comprehensive stroke centers (CSC) for mechanical thrombectomy (MT). In many cases, prehospital multi-parameter scores are used by trained emergency teams to identify patients with high probability of LVO. However, in several countries, the first aid organization without intervention of skilled staff precludes the on-site use of such scores. Here, we assessed the accuracy of LVO prediction using a single parameter (i.e. complete hemiplegia) obtained by bystander's telephone-based witnessing. PATIENTS AND METHODS: This observational, single-center study included consecutive patients who underwent intravenous thrombolysis at the primary stroke center and/or were directly transferred to a CSC for MT, from January 1, 2015 to March 1, 2020. We defined two groups: patients with initial hemiplegia (no movement in one arm and leg and facial palsy) and patients without initial hemiplegia, on the basis of a bystander's witnessing. RESULTS: During the study time, 874 patients were included [mean age 73 years (SD 13.8), 56.7% men], 320 with initial hemiplegia and 554 without. The specificity of the hemiplegia criterion to predict LVO was 0.88, but its sensitivity was only 0.53. CONCLUSION: Our results suggest that the presence of hemiplegia as witnessed by a bystander can predict LVO with high specificity. This single criterion could be used for decision-making about direct transfer to CSC for MT when the absence of emergency skilled staff precludes the patient's on-site assessment, especially in regions distant from a CSC.

Complications During Inter-Hospital Transfer of Patients with Acute Ischemic Stroke for Endovascular Therapy.

Purpose: Few data are available on complications occurring during inter-hospital transfer from a primary stroke center (PSC) to a comprehensive stroke center (CSC) for endovascular treatment (EVT) after large vessel occlusion (LVO). Therefore, we prospectively studied data from consecutive patients transferred from our PSC to the next CSC during 4 years to determine the incidence and risk factors of complications during transfer. Methods: This observational, single-center study included consecutive patients transferred from January 1, 2015 to December 31, 2018. During inter-hospital transfer, all medical incidents were systematically recorded. A new complete clinical examination was performed on arrival at the CSC. Results: Among the 253 patients transferred to the CSC during the study period, 68 (26.9%) had one or more complications. In 11 patients (4.3%) these were life-threatening and required emergency intervention by a physician. Baseline characteristics were not different between patients with and without complications, except for the LVO location. Specifically, basilar artery (BA) occlusion was strongly associated with complications during the transport (p < 0.0005). Conclusion: Complications occurred in 26.9% of patients during transfer. Only BA occlusion could predict complication during transfer. Future studies should identify variables to help stratifying patients at high and low risk of complications during transportation.

Which Patients Require Physician-Led Inter-Hospital Transport in View of Endovascular Therapy?

INTRODUCTION: The current guidelines advocate the implementation of stroke networks to organize endovascular treatment (ET) for patients with acute ischemic stroke due to large vessel occlusion (LVO) after transfer from a Primary Stroke Centre (PSC) to a Comprehensive Stroke Centre (CSC). In France and in many other countries around the world, these transfers are carried out by a physician-led mobile medical team. However, with the recent broadening of ET indications, their availability is becoming more and more critical. Here, we retrospectively analysed data of patients transferred from a PSC to a CSC for potential ET to identify predictive factors of major complications (MC) at departure and during transport that absolutely require the presence of a physician during interhospital transfer. METHODS: This observational, single-centre study included patients with evidence of intracranial LVO transferred for ET from Perpignan to a 156 km-distant CSC between January 1, 2015 and -December 31, 2018. We compared 2 groups: MC group (patients who required emergency intervention by the medical team due to life-threatening complications, including need of mechanical ventilation at departure) and non-MC group (all other patients who experienced no or only minor complications that could be managed by the emergency paramedics alone). RESULTS: Among the 253 patients who were transferred to the CSC, 185 (73.1%) had no complication, 57 (22.6%) minor complications, and 11 (4.3%) had MC. In multivariate analysis, MC was associated with basilar artery (BA) occlusion (p < 0.0001), initial National Institute of Health Stroke Scale (NIHSS) score >22 (p < 0.005), and history of atrial fibrillation (p < 0.04). Among the 168 patients treated with intravenous thrombolysis (IVT), only 1 patient (0.6%) had MC due to an IVT-related adverse event during transfer. CONCLUSIONS: Physician-led inter-hospital transports are warranted for patients with BA occlusion, initial NIHSS score >22, or history of atrial fibrillation. For the other patients, transfer without a physician may be considered, even if treated with IVT.

Shortening time to reperfusion after transfer from a primary to a comprehensive stroke center.

BACKGROUND: This study assessed whether a quality improvement (QI) process to streamline transfer from a primary stroke center (PSC) to a comprehensive stroke center (CSC) could reduce the delay of reperfusion by mechanical thrombectomy (MT). METHODS: From 2015 to 2017, a QI process was implemented with specific interventions to reduce door-in-to-door-out (DIDO) time in a high volume PSC, and speed up interhospital transfer and inhospital processes at the CSC. Clinical characteristics and time metrics were compared in the QI (2015-2017; n = 157) and pre-QI cohorts (2012-2014; n = 121). RESULTS: During the QI process, the median symptom onset to reperfusion time was reduced by 50 minutes (367 vs 417 minutes in the pre-QI cohort, p < 0.04), with a substantial 40-minute DIDO reduction (78 vs 118 minutes, p < 0.01), related to the faster administration of IV thrombolysis (median door-to-needle time: 49 vs 82 minutes, p = 0.0001). The door-to-door time was shortened (170 vs 205 minutes, p = 0.002), but not the transfer time (92 vs 87 minutes, p = 0.5). The QI process had no effect on the prehospital phase (77 vs 76 minutes, p = 0.83) and on the time from MRI imaging at the PSC to reperfusion (252 vs 288 minutes, p = 0.12). The rate of modified Rankin Scale score 0-2 at 90 days was comparable in the pre-QI and QI cohorts. CONCLUSIONS: A QI process can reduce the reperfusion therapy delay in a distant CSC; however, we could not demonstrate that it can also improve the outcome of patients who undergo MT.

Mechanical Recanalization after Transfer from a Distant Primary Stroke Center: Effectiveness and Future Directions.

INTRODUCTION: Little is known about the effectiveness of endovascular treatment (EVT) in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) admitted to a primary stroke center (PSC). The aim of this study was to assess EVT effectiveness after transfer from a PSC to a distant (156 km apart; 1.5 hour by car) comprehensive stroke center (CSC), and to discuss perspectives to improve access to EVT, if indicated. PATIENTS AND METHOD: Analysis of the data collected in a 6-year prospective registry of patients admitted to a PSC for AIS due to LVO and selected for transfer to a distant CSC for EVT. The rate of transfer, futile transfer, EVT, reperfusion (thrombolysis in cerebral infarction score ≥2b-3), and relevant time measures were determined. RESULTS: Among the 529 patients eligible, 278 (52.6%) were transferred and 153 received EVT (55% of transferred patients) followed by reperfusion in 115 (overall reperfusion rate: 21.7%). Median times (interquartile range) were: 90 minutes (76-110) for PSC-door-in to PSC-door-out, 88 minutes (65-104) for PSC-door-out to CSC-door-in, 262 minutes (239-316) for PSC-imaging to reperfusion, and 393 minutes (332-454) for symptom onset to reperfusion. At 3 months, rates of favorable outcome (modified Rankin Scale 0-2) were not significantly different between patients eligible for EVT (42.4%), transferred patients (49.1%) and patients who underwent EVT (34.1%). DISCUSSION AND CONCLUSIONS: Our study suggests that transfer to a distant CSC is associated with reduced access to early EVT. These results argue in favor of on-site EVT at high volume PSCs that are distant from the CSC.

Futile inter-hospital transfer for mechanical thrombectomy in a semi-rural context: analysis of a 6-year prospective registry.

BACKGROUND AND PURPOSE: Inter-hospital transfer for mechanical thrombectomy (MT) might result in the transfer of patients who finally will not undergo MT (ie, futile transfers [FT]). This study evaluated FT frequency in a primary stroke center (PSC) in a semi-rural area and at 156 km from the comprehensive stroke center (CSC). METHODOLOGY: Retrospective analysis of data collected in a 6-year prospective registry concerning patients admitted to our PSC within 4.5 hours of acute ischemic stroke (AIS) symptom onset, with MR angiography indicating the presence of large vessel occlusion (LVO) without large cerebral infarction (DWI-ASPECT ≥5), and selected for transfer to the CSC to undergo MT. Futile transfer rate and reasons were determined, and the relevant time measures recorded. RESULTS: Among the 529 patients screened for MT, 278 (52.6%) were transferred to the CSC. Futile transfer rate was 45% (n=125/278) and the three main reasons for FT were: clinical improvement and reperfusion on MRI on arrival at the CSC (58.4% of FT); clinical worsening and/or infarct growth (16.8%); and longer than expected inter-hospital transfer time (11.2%). Predictive factors of FT due to clinical improvement/reperfusion on MRI could not be identified. Baseline higher NIHSS (21 vs 17; P=0.01) and lower DWI-ASPECT score (5 vs 7; P=0.001) were associated with FT due to clinical worsening/infarct growth on MRI. CONCLUSIONS: In our setting, 45% of transfers for MT were futile. None of the baseline factors could predict FT, but the initial symptom severity was associated with FT caused byclinical worsening/infarct growth.

Target Door-to-Needle Time for Tissue Plasminogen Activator Treatment with Magnetic Resonance Imaging Screening Can Be Reduced to 45 min.

OBJECTIVE: The purpose of this study was to demonstrate that the median door-to-needle (DTN) time for intravenous tissue plasminogen activator (tPA) treatment can be reduced to 45 min in a primary stroke centre with MRI-based screening for acute ischaemic stroke (AIS). METHODS: From February 2015 to February 2017, the stroke unit of Perpignan general hospital, France, implemented a quality-improvement (QI) process. During this period, patients who received tPA within 4.5 h after AIS onset were included in the QI cohort. Their clinical characteristics and timing metrics were compared each semester and also with those of 135 consecutive patients with AIS treated by tPA during the 1-year pre-QI period (pre-QI cohort). RESULTS: In the QI cohort, 274 patients (92.5%) underwent MRI screening. While the demographic and baseline characteristics were not significantly different between cohorts, the median DTN time was significantly lower in the QI than in the pre-QI cohort (52 vs. 84 min; p < 0.00001). Within the QI cohort, the median DTN time for each semester decreased from 65 to 44 min (p < 0.00001) and the proportion of treated patients with a DTN time ≤45 min increased from 25 to 58.9% (p < 0.0001). Overall, DTN time improvement was associated with a better outcome at 3 months (patients with a modified Rankin Scale score between 0 and 2: 61.8% in the QI vs. 39.3% in the pre-QI cohort; p < 0.0001). CONCLUSIONS: A QI process can reduce the DTN within 45 min with MRI as a screening tool.

Percutaneous osteosynthesis in the pelvis in cancer patients.

PURPOSE: Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. We report our experience in cancer patients. MATERIAL/METHODS: We retrospectively reviewed all cases of percutaneous osteosynthesis (PO) of the pelvic ring and proximal femur performed in our hospital. PO were performed for fracture palliation or for osteolytic metastases consolidation. Screws were inserted under CT- or cone-beam CT- guidance and general anaesthesia. Patients were followed-up with pelvic-CT and medical consultation at 1 month, then every 3 months. For fractures, the goal was pain palliation and for osteolytic metastases, pathologic fracture prevention. RESULTS: Between February 2010 and August 2014, 64 cancer patients were treated with PO. Twenty-one patients had PO alone for 33 painful fractures (13 bone-insufficiency, 20 pathologic fractures). The pain was significantly improved at 1 month (VAS score = 20/100 vs. 80/100). In addition, 43 cancer patients were preventively consolidated using PO plus cementoplasty for 45 impending pathologic fractures (10 iliac crests, 35 proximal femurs). For the iliac crests, no fracture occurred (median-FU = 75 days). For the proximal femurs, 2 pathological fractures occurred (fracture rate = 5.7 %, median-FU = 205 days). CONCLUSION: PO is a new tool in the therapeutic arsenal of interventional radiologists for bone pain management. KEY POINTS: • Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. • CT- or CBCT-guidance results in high technical success rates for screw placement. • This minimally invasive technique avoids extensive surgical exposure in bone cancer patients. • Osteosynthesis provides pain relief for bone-insufficiency fractures and for pathologic fractures. • Osteosynthesis plus cementoplasty provide prophylactic consolidation of impending pathological fractures.

Percutaneous bone biopsies: comparison between flat-panel cone-beam CT and CT-scan guidance.

PURPOSE: This study was designed to compare the accuracy of targeting and the radiation dose of bone biopsies performed either under fluoroscopic guidance using a cone-beam CT with real-time 3D image fusion software (FP-CBCT-guidance) or under conventional computed tomography guidance (CT-guidance). METHODS: Sixty-eight consecutive patients with a bone lesion were prospectively included. The bone biopsies were scheduled under FP-CBCT-guidance or under CT-guidance according to operating room availability. Thirty-four patients underwent a bone biopsy under FP-CBCT and 34 under CT-guidance. We prospectively compared the two guidance modalities for their technical success, accuracy, puncture time, and pathological success rate. Patient and physician radiation doses also were compared. RESULTS: All biopsies were technically successful, with both guidance modalities. Accuracy was significantly better using FP-CBCT-guidance (3 and 5 mm respectively: p = 0.003). There was no significant difference in puncture time (32 and 31 min respectively, p = 0.51) nor in pathological results (88 and 88 % of pathological success respectively, p = 1). Patient radiation doses were significantly lower with FP-CBCT (45 vs. 136 mSv, p < 0.0001). The percentage of operators who received a dose higher than 0.001 mSv (dosimeter detection dose threshold) was lower with FP-CBCT than CT-guidance (27 vs. 59 %, p = 0.01). CONCLUSIONS: FP-CBCT-guidance for bone biopsy is accurate and reduces patient and operator radiation doses compared with CT-guidance.

Predisposing factors of liver necrosis after transcatheter arterial chemoembolization in liver metastases from neuroendocrine tumor.

PURPOSE: To investigate predictive factors for liver necrosis after transcatheter arterial chemoembolization (TACE) of neuroendocrine liver metastases. METHODS: A total of 164 patients receiving 374 TACE were reviewed retrospectively to analyze predictive factors of liver necrosis. We analyzed patient age and sex; metastasis number and location; percentage of liver involvement; baseline liver function test; and pretreatment imaging abnormalities such as bile duct dilatation (BDD), portal vein narrowing (PVN), and portal vein thrombosis (PVT). We analyzed TACE technique such as Lipiodol or drug-eluting beads (DEB) as the drug's vector; dose of chemotherapy; diameter of DEB; and number, frequency, and selectivity of TACE. RESULTS: Liver necrosis developed after 23 (6.1 %) of 374 TACE. In multivariate analysis, DEB > 300 µm in size induced more liver necrosis compared to Lipiodol (odds ratio [OR] 35.20; p < 0.0001) or with DEB < 300 µm in size (OR 19.95; p < 0.010). Pretreatment BDD (OR 119.64; p < 0.0001) and PVT (OR 9.83; p = 0.030) were predictive of liver necrosis. BDD or PVT responsible for liver necrosis were present before TACE in 59 % (13 of 22) and were induced by a previous TACE in 41 % (9 of 22) of cases. CONCLUSION: DEB > 300 µm in size, BDD, and PVT are responsible for increased rate of liver necrosis after TACE. Careful analysis of BDD or PVT on pretreatment images as well as images taken between two courses can help avoid TACE complications.

A role for adjuvant RFA in managing hepatic metastases from gastrointestinal stromal tumors (GIST) after treatment with targeted systemic therapy using kinase inhibitors.

PURPOSE: This study was designed to assess the role of radiofrequency ablation (RFA) in the multimodality management of gastrointestinal stromal tumors (GIST) in patients undergoing targeted tyrosine kinase inhibitor therapy (TKI) for liver metastases. METHODS: Outcomes of 17 patients who underwent liver RFA for 27 metastatic GIST after TKI therapy, from January 2004 to March 2012, were retrospectively analyzed. Mean maximum tumor diameter was 2.5 ± 1 cm (range 0.9-4.5 cm). In seven patients (group A), RFA of all residual tumors was performed, with curative intent, and TKI therapy was discontinued. In five patients (group B), RFA of all residual tumors was performed upon achieving the best morphological response with TKI therapy, which was maintained after RFA. In another five patients (group C), RFA was performed on individual liver metastases which were progressive under TKI therapy. RESULTS: All 27 targeted tumors were completely ablated, without local recurrence during the mean follow-up period of 49 months. No major complications occurred. Two minor complications were reported (11 %). Only two patients (both in group C) died at 20 and 48 months. Two-year progression-free survival (PFS) after RFA was 29 % in group A, 75 % in group B, and 20 % in group C. CONCLUSIONS: RFA in patients, previously treated with TKI, is feasible and safe. Our data suggest that RFA is a useful therapeutic option in patients with metastatic GIST and should be performed at the time of best clinical response with patient maintained under TKI after the procedure.

Coil-assisted RFA of poorly visible liver tumors: effectiveness and risk factors of local tumor progression.

OBJECTIVES: This study was designed to determine the effectiveness of a percutaneously inserted coil as a landmark before radiofrequency ablation (RFA) of poorly visible liver tumors on unenhanced computed tomography and ultrasound. METHODS: This was a single-center, retrospective study of 46 consecutive patients treated from January 2008 to June 2012 with RFA under CT guidance for 57 poorly visible liver tumors after percutaneous coil insertion. Effectiveness was evaluated by the rate of local tumor progression (LTP), and the risk factors of LTP were evaluated by multiple univariate analysis. RESULTS: After a mean follow-up of 15.9 months, the overall rate of LTP was 22.8 % (13/57). An increase in the distance between the coil and the center of the tumor was a predictive factor of LTP (p = 0.005) and resulted in an increase in time to place the RFA probe. LTP was significantly reduced in case of coil placed within the tumor (10 vs. 43.5 %, p = 0.009). CONCLUSIONS: The effectiveness of the "coil-assisted" RFA for poorly visible liver tumors is improved by centering the coil in the tumor in order to facilitate the placement of the RFA probe and equal to the results of RFA under direct image guidance.

Prospective comparison of freehand and electromagnetic needle tracking for US-guided percutaneous liver biopsy.

PURPOSE: To prospectively compare electromagnetic needle tracking (EMT) and freehand ultrasound (US)-guided liver biopsies. MATERIALS AND METHODS: Among 60 consecutive US-guided liver biopsies performed by staff radiologists (senior operators) and residents (junior operators), 30 were performed freehand and 30 with EMT. Needle placement time, numbers of needle punctures and pullbacks, and subjective scores of procedure difficulty were compared by χ(2) or Student t test. RESULTS: Diagnostic success rates, defined by the procurement of an adequate histopathologic specimen, were 96.6% for freehand biopsy and 100% with EMT. Needle placement time was significantly lower for EMT (mean ± standard deviation, 45.8 s ± 48.1) than for freehand procedures (143.2 s ± 122.1; P < .01). In the freehand group, needle placement times were 179.6 seconds ± 133.3 for junior operators and 106.8 seconds ± 101.3 for senior operators (P = .15). In the EMT group, needle placement times were 49.2 seconds ± 55 for junior operators and 42.5 seconds ± 41.2 for senior operators (P = .53). The number of needle pullbacks was significantly lower for senior operators (1.2 ± 0.80) compared with junior operators (2.4 ± 1.4) in the freehand group (P = .01), with no significant difference (junior, 0.47 ± 0.92; senior, 0.67 ± 0.72; P = .24) in the EMT group. The postprocedural difficulty score was lower in the EMT group (1.5 ± 0.7) than in the freehand group (2.1 ± 1.1; P = .02). Needle placement time and number of needle pullbacks were lower in the EMT group, even after taking into account tumor size and depth and operator experience. CONCLUSIONS: The EMT procedure shortens needle placement time and reduces the number of needle pullbacks needed for redirection, regardless of operator experience.

Polytetrafluoroethylene-covered nitinol stent graft for treatment of carotid artery blowout syndrome in head and neck cancer patients.

OBJECTIVES/HYPOTHESIS: To evaluate the efficacy, tolerance, and outcomes of covered stents in the treatment of carotid blowout syndrome (CBS) in head and neck cancer patients. STUDY DESIGN: Individual retrospective cohort study. METHODS: We retrospectively reviewed the medical and image files of all 20 consecutive head and neck cancer patients treated with covered stent grafts for CBS. Six acute, 12 impending, and two threatened cases of CBS were treated in patients who all had previously received radiation therapy. We evaluated the feasibility, hemostatic efficacy, survival without bleeding, and complications. RESULTS: The etiologies of CBS were as follows: group 1, 13 carotid axis (common or internal carotid artery) pseudoaneurysms and one rupture; group 2, six patients with no identifiable source of bleeding on angiography but with a threatened carotid axis on computed tomography (CT). In all patients, a polytetrafluoroethylene-covered nitinol stent graft (Fluency; Bard/Angiomed GmbH & Co, Karlsruhe, Germany) was successfully placed. All of the stents were patent at the end of the procedure. Immediate hemostasis was achieved in the six hemorrhagic cases. Immediate transient ischemic attacks were observed in two patients, and carotid sinus syndrome was observed in one patient. Post-treatment bleeding was observed in five patients in group 2 and no patients in group 1. Survival without bleeding was 251 days in group 1 and 35 days in group 2. During follow-up, three asymptomatic stent thromboses occurred at a mean of 58 days. CONCLUSIONS: Covered stent placement is highly feasible and proved effective without major complications in CBS due to carotid axis bleeding.

In vivo evaluation of lung microwave ablation in a porcine tumor mimic model.

PURPOSE: To evaluate the microwave ablation of created tumor mimics in the lung of a large animal model (pigs), with examination of the ablative synergy of multiple antennas. METHODS: Fifty-six tumor-mimic models of various sizes were created in 15 pigs by using barium-enriched minced collected thigh muscle injected into the lung of the same animal. Tumors were ablated under fluoroscopic guidance by single-antenna and multiple-antenna microwaves. RESULTS: Thirty-five tumor models were treated in 11 pigs with a single antenna at 75 W for 15 min, with 15 measuring 20 mm in diameter, 10 measuring 30 mm, and 10 measuring 40 mm. Mean circularity of the single-antenna ablation zones measured 0.64 ± 0.12, with a diameter of 35.7 ± 8.7 mm along the axis of the antenna and 32.7 ± 12.8 mm perpendicular to the feeding point. Multiple-antenna delivery of 75 W for 15 min caused intraprocedural death of 2 animals; modified protocol to 60 W for 10 min resulted in an ablation zone with a diameter of 43.0 ± 7.7 along the axis of the antenna and 54.8 ± 8.5 mm perpendicular to the feeding point; circularity was 0.70 ± 0.10 CONCLUSIONS: A single microwave antenna can create ablation zones large enough to cover lung tumor mimic models of ≤4 cm with no heat sink effect from vessels of ≤6 mm. Synergic use of 3 antennas allows ablation of larger volumes than single-antenna or radiofrequency ablation, but great caution must be taken when 3 antennas are used simultaneously in the lung in clinical practice.

Interventional revisions of malfunctions affecting surgically implanted port-catheters for hepatic artery infusion.

PURPOSE: Despite high response rates, feasibility of hepatic artery infusion (HAI) is impaired by frequent malfunctions of surgically implanted catheters (SIC). The aim of this study is to analyze the incidence and the types of malfunctions affecting the SIC and the success rate of interventional revisions (IR) in restoring patency to these catheters. METHODS: In a single center, 101 consecutive patients treated with HAI through SIC over 10 years were retrospectively reviewed. The studied group (+IR) was composed of patients referred to interventional radiology for repair of catheter malfunctions. The overall patency of catheters in the +IR group was compared with the overall patency of a control group composed of patients without catheter malfunction (no IR). RESULTS: 86 patients were included with no difference in baseline characteristics between +IR (n = 40) and no IR (n = 46). There were no significant differences in overall patency between both groups (8.4 courses vs. 8.4 courses, p = 0.99). Furthermore, with an overall success rate of 72.5%, IR significantly improved the mean primary patency from 2.4 to 8.4 courses (p < 0.0001) in the +IR group. CONCLUSION: By restoring a normal patency to SIC affected by different types of malfunctions, IR improves feasibility of HAI.

Lung cancer ablation: what is the evidence?

Percutaneous ablation of small non-small cell lung cancer (NSCLC) has been demonstrated to be both feasible and safe in nonsurgical candidates. Radiofrequency ablation (RFA), the most commonly used technique for ablation, has a reported rate of complete ablation of ~90%, with best results obtained in tumors <2 to 3 cm in diameter. The best reported 1-, 3-, and 5-year overall survival rates after RFA of NSCLC are 97.7%, 72.9%, and 55.7%, respectively. It is noteworthy that in most studies, cancer-specific survival is greater than overall survival due to severe comorbidities in patients treated with RFA for NSCLC. Aside from tumor size and tumor stage, these comorbidities are predictive of survival. Other ablation techniques such as microwave and irreversible electroporation may in the future prove to overcome some of the limitations of RFA, namely for large tumors or tumors close to large vessels. Stereotactic body radiation therapy has also been demonstrated to be highly efficacious in treating small lung tumors and will need to be compared with percutaneous ablation. This article reviews the current evidence regarding RFA for lung cancer.

Cementoplasty of metastases of the proximal femur: is it a safe palliative option?

PURPOSE: Percutaneous cementoplasty has proved very effective for the palliation of pain from bone metastases. However, several studies argue that it should be contraindicated for metastases that are located in the proximal femur because of inadequate bone consolidation. The aim of this study was to evaluate the risk factors for fracture despite performing cementoplasty for metastases of the proximal femur. METHODS: We retrospectively analyzed all consecutive patients who underwent cementoplasty for metastases of the proximal femur who had a high risk for fracture (N = 21) from June 2003 to October 2010. Cementoplasty was performed for preventive consolidation as well as for pain palliation in 16 patients. The risk factors studied were the patient characteristics, the Mirels score, the maximal size and cortical involvement of the lesion, and a history of a previous fracture of the lesser trochanter. RESULTS: The 1-year pathologic fracture rate was 40.6% (seven fractures). The risk of fracture was significantly higher for cortical involvement greater than 30 mm (n = 7/11 vs n = 0/10; P = .0005) and a history of a previous fracture of the lesser trochanter (n = 3/3 vs 4/18; P = .0009). CONCLUSIONS: Percutaneous cementoplasty can be considered for patients with metastases of the proximal femur under certain conditions: cortical involvement less than 30 mm and no history of a fracture of the lesser trochanter. Otherwise, the risk of fracture is too high, and cementoplasty is contraindicated.