Functional Outcome Following Stroke Thrombectomy in Clinical Practice.

Background and Purpose- Endovascular treatment for large vessel occlusion in ischemic stroke has proven to be effective in large clinical trials. We aimed to provide real-world estimates of endovascular treatment reperfusion rates and functional outcome on a countrywide scale. Methods- Two thousand seven hundred ninety-four patients with large vessel occlusion were included into an investigator-initiated, industry-independent, prospective registry in 25 sites in Germany between June 2015 and April 2018. The primary outcome was the score on the modified Rankin Scale ranging from zero (no symptoms) to 6 (death) at 3 months. Secondary analyses included the prediction of a good outcome (modified Rankin Scale, 0-2). Dichotomized analyses of predictors were performed using logistic regression adjusted for potential confounders. Results- Median age was 75 years (interquartile range, 64-82); median National Institutes of Health Stroke Scale score was 15 (interquartile range, 10-19). Vessel occlusion was in the anterior circulation in 2265 patients (88%) and in the posterior circulation in 303 patients (12%). Intravenous alteplase before endovascular treatment was given in 1457 patients (56%). Successful reperfusion was achieved in 2143 subjects (83%). At 3 months, 854 patients (37%) showed a good outcome; mortality was 29%. There was no difference between anterior and posterior circulation occlusions (P=0.27). Significant predictors for a good outcome were younger age (odds ratio [OR], 1.06; 95% CI, 1.05-1.07), no interhospital transfer (OR, 1.39; 95% CI, 1.03-1.88), lower stroke severity (OR, 1.10; 95% CI, 1.08-1.13), smaller infarct size (OR, 1.26; 95% CI, 1.15-1.39), alteplase use (OR, 1.49; 95% CI, 1.08-2.06), and reperfusion success (OR, 1.69; 95% CI, 1.45-1.96). Conclusions- High rates of favorable outcome can be achieved on a countrywide scale by endovascular treatment. Mortality appears to be greater in the daily routine than otherwise reported by authors of large randomized trials. There were no outcome differences between the anterior and posterior circulation. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT03356392.

Incidental Findings in Abdominal Dual-Energy Computed Tomography: Correlation Between True Noncontrast and Virtual Noncontrast Images Considering Renal and Liver Cysts and Adrenal Masses.

PURPOSE: To assess correlation between attenuation measurements of incidental findings in abdominal second generation dual-energy computed tomography (CT) on true noncontrast (TNC) and virtual noncontrast (VNC) images. MATERIALS AND METHODS: Sixty-three patients underwent arterial dual-energy CT (Somatom Definition Flash, Siemens; pitch factor, 0.75-1.0; gantry rotation time, 0.28 seconds) after endovascular aneurysm repair, consisting of a TNC single energy CT scan (collimation, 128 × 0.6 mm; 120 kVp) and a dual-energy arterial phase scan (collimation, 32 × 0.6 mm, 140 and 100 kVp; blended, 120 kVp data set). Attenuation measurements in Hounsfield units (HU) of liver parenchyma and incidental findings like renal and hepatic cysts and adrenal masses on TNC and VNC images were done by drawing regions of interest. Statistical analysis was performed by paired t test and Pearson correlation. RESULTS: Incidental findings were detected in 56 (89%) patients. There was excellent correlation for both renal (n = 40) and hepatic cysts (n = 12) as well as adrenal masses (n = 6) with a Pearson correlation of 0.896, 0.800, and 0.945, respectively, and mean attenuation values on TNC and VNC images of 10.6 HU ± 12.8 versus 5.1 HU ± 17.5 (attenuation value range from -8.8 to 59.1 HU vs -11.8 to 73.4 HU), 6.4 HU ± 5.8 versus 6.3 HU ± 4.6 (attenuation value range from 2.0 to 16.2 HU vs -3.0 to 15.9 HU), and 12.8 HU ± 11.2 versus 12.4 HU ± 10.2 (attenuation value range from -2.3 to 27.5 HU vs -2.2 to 23.6 HU), respectively. As proof of principle, liver parenchyma measurements also showed excellent correlation between TNC and VNC (n = 40) images with a Pearson correlation of 0.839 and mean attenuation values on TNC and VNC images of 47.2 HU ± 10.5 versus 43.8 HU ± 8.7 (attenuation value range from 21.9 to 60.2 HU vs 4.5 to 65.3 HU). CONCLUSIONS: In conclusion, attenuation measurements of incidental findings like renal cysts or adrenal masses on TNC and VNC images derived from second generation dual-energy CT scans show excellent correlation providing considerable dose savings, favorable for future application in clinical routine.

Brentuximab vedotin for relapsed or refractory CD30+ hematologic malignancies: the German Hodgkin Study Group experience.

The CD30-targeting Ab-drug conjugate brentuximab vedotin (SGN-35) was recently approved for the treatment of relapsed Hodgkin lymphoma and anaplastic large-cell lymphoma by the Food and Drug Administration. In the present study, we report the experience of the German Hodgkin Study Group with brentuximab vedotin as single agent in 45 patients with refractory or relapsed CD30(+) Hodgkin lymphoma who were treated either in a named patient program (n = 34) or in the context of a safety study associated with the registration program of this drug. In these very heavily pretreated patients, an objective response rate of 60%, including 22% complete remissions, could be documented. The median duration of response was 8 months. This retrospective analysis supports the previously reported excellent therapeutic efficacy of brentuximab vedotin in heavily pretreated CD30(+) malignancies.

Feasibility and effectiveness of posaconazole prophylaxis in combination with micafungin bridging for patients undergoing allogeneic stem cell transplantation: a 6-yr analysis from the cologne cohort for neutropenic patients.

INTRODUCTION: Invasive fungal diseases (IFDs) are an important cause of morbidity and mortality in patients undergoing allogeneic stem cell transplantation (SCT). METHODS: To compare the effectiveness of two prophylactic antifungal regimens used as standard of care (SOC) in the setting of SCT during the periods of May 2006 - September 2009 (oral posaconazole, POS) and October 2009 - July 2011 (oral posaconazole with intravenous micafungin bridging, POS-MIC), data from the Cologne Cohort of Neutropenic Patients (CoCoNut) study were analyzed after nearest-neighbor matching. Endpoints were occurrence of breakthrough probable/proven IFD under prophylaxis, incidence and duration of persistent febrile neutropenia, incidence of unspecific pneumonic infiltrates, possible IFD, positive galactomannan tests, as well as fungal-free and overall survival. RESULTS: Of 291 patients with 307 SCTs observed during the study period, 212 fulfilled the inclusion criteria and were included into the analysis. Patients receiving POS-MIC were less likely to develop a pneumonic infiltrate (RR 0.71, 95% CI 0.51-1.00) or possible IFD (RR 0.36, 95% 0.15-0.87). They also demonstrated improved fungal-free survival at day 100 (P = 0.009). No significant differences were observed for the incidence of probable or proven IFD, positive galactomannan tests, persistent febrile neutropenia, duration of hospitalization and overall mortality. There was no grade III or IV CTCAE (Common Terminology Criteria for Adverse Events) toxicity related to antifungal prophylaxis. CONCLUSION: Our results suggest that both prophylactic regimens, POS and POS-MIC are feasible, safe and effective. Our data suggest that bridging with intravenous micafungin could indeed improve exposure to antifungal prophylaxis, which may explain the reduced incidence of pneumonia and IFD in the bridging group.

Thoracic type Ia endoleak: direct percutaneous coil embolization of the aortic arch at the blood entry site after TEVAR and double-chimney stent-grafts.

OBJECTIVES: To introduce a novel percutaneous technique to stop blood entry at the lesser aortic arch curvature by coil embolisation in type Ia endoleak after TEVAR. METHODS: A 61-year-old Marfan patient presented with type Ia endoleak of the aortic arch and a growing aortic arch pseudoaneurysm after TEVAR. Multiple preceding operations and interventions made an endovascular approach unsuccessful. Direct percutaneous puncture of the aneurysmal sac would have cured the sign, but not the cause of blood entry at the lesser curvature of the aortic arch. Direct CT-guided percutaneous puncture of the blood entry site in the aortic arch with fluoroscopically guided coil embolisation using detachable extra-long coils was successfully performed. RESULTS: Three weeks after the intervention, the patient developed fever because of superinfection of the pseudoaneurysm. The blood cultures and CT-guided mediastinal aspirate were sterile. After intravenous administration of antibiotics, the fever disappeared and the patient recovered. Six-month follow-up showed permanent closure of the endoleak and a shrinking aneurysmal sac. CONCLUSIONS: Direct percutaneous puncture of the aortic arch at the blood entry site of a thoracic type Ia endoleak after TEVAR and double-chimney stent-grafts with coil embolisation of the wedge-shaped space between the lesser aortic curvature and the stent-graft is possible. KEY POINTS: Endoleaks after thoracic endovascular aortic repair are common in 15-30 %. Most endoleaks can be treated by endovascular means. Direct percutaneous endoleak repair is described as a bail-out option. Direct percutaneous aortic arch coil embolisation of type 1a endoleak is possible. Antibiotic prophylaxis should be administered case by case, considering individual risk factors.

Cardiac liposarcoma-a review of outcome after surgical resection.

OBJECTIVE: This review was performed to pool the current surgical strategies for cardiac liposarcoma. METHODS: A literature search was performed and all studies published in full-text or abstract forms were eligible for inclusion without applying any language restrictions. Case reports without surgical intervention, reporting noncardiac liposarcoma, animal cases, or review articles were excluded after initial abstract review. Analyzed postoperative outcomes included intraoperative and in-hospital mortality, longest reported survival, and recrudescence. RESULTS: After a critical evaluation 53 unique surgically treated case reports published between the years 1966 and December 2012 were included in this review. Most of the reported cardiac liposarcoma are myxoid (49.1%), pleomorphic liposarcoma occur with a prevalence of 20.8%, and well-differentiated tumors are observed in 13.2%. One-year survival rate increases the more differentiated the tumor is categorized: 54.5% for pleomorphic, 65.4% for myxoid, and 100% for well-differentiated liposarcoma (p = 0.096). CONCLUSION: Total surgical resection of cardiac liposarcoma is the only curative option, as it tends to local and distant recurrence. Therefore, a frequent follow-up examination should be considered.

The laparoscopic approach for radiofrequency ablation of hepatocellular carcinoma--indication, technique and results.

BACKGROUND: The therapeutic regimen for patients suffering of HCC in liver cirrhosis must pay attention to the underlying liver disease. Surgical resection is often limited by liver function and transplantation, as an optimal therapy for many early diagnosed HCC, by the availability of organs. Due to three prospective, randomized trials radiofrequency ablation (RFA) is the standard method of local ablation. RFA compared with resection for HCC in liver cirrhosis yields similar results concerning overall survival but a lower rate of complications. The laparoscopic approach may be advantageous concerning the major drawback of RFA which is still the rate of local failure as shown by a meta-analysis of local recurrences. METHOD: Indication for RFA was HCC in liver cirrhosis either as a definite therapy or as a bridging procedure for transplantation if the expected waiting time exceeded 6 months. Laparoscopic ultrasound, standardized algorithm of laparoscopic RFA procedure, track ablation and a Trucut biopsy were performed. The postoperative follow-up was done according to institutional standards. Patient data and parameters of laparoscopic RFA were prospectively documented, analyzed and compared with the results of previously published series found in a Medline search. RESULTS: 34 patients were treated by laparoscopic RFA. The average time of follow-up was 36.9 ± 28.3 months. There was no procedure-related mortality or surgical complications. An upstaging of the tumor stage by laparoscopic ultrasound was achieved in 32 % of the patients. The overall survival of these patients was 44.7 ± 6.9 months. The intrahepatic recurrence rate was 61.8 % based on the number of patients treated. The results have been analyzed and compared with six independent papers identified in a Medline search that report on the treatment of patients with HCC in a liver cirrhosis by laparoscopic RFA with a mean follow-up of 12 or more months. CONCLUSIONS: Laparoscopic RFA is a feasible and reliable therapy for unresectable HCCs in patients with cirrhosis. The laparoscopic RFA combines the advantage of a minimally invasive procedure concerning liver dysfunction with the ability of an accurate intraoperative staging by laparoscopic ultrasound.

Mucinous cystic neoplasm or non-parasitic liver cyst? - A challenging diagnosis.

BACKGROUND/AIMS: Mucinous cystic neoplasms (MCN) are rare liver lesions. Radiological features include internal septa or septal thickening. Imaging often fails in the differential diagnosis to non-parasitic liver cysts (NPLC), resulting in inadequate surgery. The aim of the study was to evaluate if both lesions could be differentiated pre-operatively. METHODOLOGY: Retrospective study with literature review. RESULTS: Twenty-six patients (22 female, 68±12 years) underwent laparoscopic deroofing for NPLC. Histo-pathological specimens showed 2 MCN (both female) with recurrence rates of 4% (NPLC) and 100% (MCN), and a time-to-recurrence of 3 months. In both cases no radiological features of MCN were seen pre-operatively. Follow-up time was 7 and 12 years with emergence of radiological features of MCN in one case. PubMed search showed 137 hits for "MCN" and 540 hits for "mucinous cystadenoma" and "liver"; 207 studies were reviewed: one prospective, 13 non-systematic reviews, 57 retrospective, 120 case reports and 16 expert opinions. The largest MCN-series included 44 subjects. CONCLUSIONS: If MCN shows no characteristic radiological features, thus mimicking NPLC, pre-operative radiological differentiation is impossible. During long time course characteristic radiological morphology of MCN could appear. Early recurrence of a supposed NPLC is suspicious for MCN. Due to the literature review pre-operative imaging is inaccurate for the differential diagnosis and complete surgical excision of MCN is crucial.

Induction of durable responses by oral etoposide monochemotherapy in patients with metastatic Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is an aggressive, rare tumour of the skin. For advanced cases with distant organ metastases several different regimens of chemotherapeutics have been described. Disease specific 5-year survival rates for these patients are approximately 11%. In this case series we report our experience with orally administered etoposide (100 mg at days 1 to 10 in a 31 day cycle) in 4 patients. We treated two male and two female patients with a median age of 68.5 years. In our four treated patients the disease control rate (complete remission, partial remission, stable disease) was 100%. Three out of four patients reached complete remission. Promisingly, two of our patients had long lasting, durable responses which, until now, have lasted for 16 and 36 months, respectively. The mean follow up time after start of therapy was 14.25 months (range 1-36 months). Etoposide treatment was generally well tolerated, the most common side effect was neutropenia, in one case CTC grade 3. In conclusion, orally administered etoposide in metastatic Merkel cell carcinoma was highly effective and well tolerated.

Large-volume multi-tined expandable RF ablation in pig livers: comparison of 2D and volumetric measurements of the ablation zone.

OBJECTIVES: To compare two-dimensional (2D) and three-dimensional (3D) computed tomography (CT) measurements of ablation zones (AZs) related to the shaft of two different large-volume monopolar multi-tined expandable electrodes. METHODS: Percutaneous radiofrequency (RF) ablation was performed in 12 pigs (81.6 +/- 7.8 kg) using two electrodes (LeVeen 5 cm, Rita XL 5 cm; n = 6 in each group). Contrast-enhanced CT with the electrode shaft in place evaluated the AZ. The largest sphere centred on the electrode shaft within the AZ was calculated (1) based on the 2D axial CT image in the plane of the shaft assuming rotational symmetry of the AZ and (2) using prototype software and the 3D volume data of the AZ measured with CT. RESULTS: The mean largest diameter of a sphere centred on the electrode shaft was always smaller using the 3D data of the AZ than using 2D CT measurements assuming rotational symmetry of the AZ (3D vs 2D): LeVeen 18.2 +/- 4.8 mm; 24.5 +/- 3.1 mm; p = 0.001; Rita XL 20.0 +/- 3.7 mm; 28.8 +/- 4.9 mm; p = 0.0002. All AZ showed indentations around the tines. CONCLUSIONS: Two-dimensional CT measurements assuming rotational symmetry of the AZ overestimate the largest ablated sphere centred on the electrode shaft compared with 3D CT measurements.

Effect of a one-session versus two-session procedure on different parameters of interventional therapy for peripheral arterial occlusive disease: results of a retrospective cohort study.

PURPOSE: To compare the effects of a one-session procedure (ie, diagnostic angiography immediately followed by intervention) versus a two-session procedure (ie, diagnostic angiography and intervention in two separate sessions) on interventional therapy in patients with peripheral arterial occlusive disease (PAOD). MATERIALS AND METHODS: Interventional therapy was performed immediately after diagnostic angiography in one session in 228 patients (group 1) and in a chronologically separate, later session in another 43 patients (group 2). The retrospectively captured parameters were Fontaine stage, TransAtlantic InterSociety Consensus II criteria, angiographic severity, type, technical success and complication rates, examination times, volume of contrast media, radiation exposure, and fluoroscopy time for intervention. RESULTS: There were no between-group differences in clinical and interventional parameters. In group 1 there were 340 interventions performed, and there were 61 in group 2 with an interval before intervention of 1-55 days. The groups showed comparable success rates (92.6% vs 91.8%; P = .79) and complication rates (5.7% vs 4.65%; P = 1.0). The examination times were similar at 82.6 minutes +/- 40.5 and 91.3 minutes +/- 69.9, respectively (P = .92). Volume of contrast media (301.7 mL +/- 81.3 vs 459.2 mL +/- 123.7) and radiation exposure (140.5 Gy/cm(2) +/- 152.1 vs 304.7 Gy/cm(2) +/- 217.4) were significantly lower in group 1 (P < .001 each). Fluoroscopy times trended lower in group 1. CONCLUSIONS: In patients with PAOD, interventional therapy of iliac and femoropopliteal artery lesions performed in the same session as diagnostic angiography yields technical success and complication rates comparable to those seen with a two-session procedure, but is associated with significantly less contrast media use and radiation exposure.

Pathomorphological changes after radiofrequency ablation in the liver.

Radiofrequency ablation (RFA) has become a widespread treatment option for liver carcinoma. There is limited knowledge regarding the macroscopic and histomorphological changes of induced lesions. Twelve domestic pigs underwent RFA using a Starburst XL device with ablation diameter of 3 cm. One animal died within 24 h, two animals were killed after 2 weeks, and nine after 4 weeks. Their livers were used for macroscopic and histological investigation. Six human liver resection specimens after previous treatment with RFA were also investigated. In pig samples, acute RFA change showed a necrosis zone demarcated by resorption zone with granulocytes and hyperemia. In subchronic and chronic RFA change, the zone of thermofixation was followed by a fibrous capsule and a liver reaction zone. Small blood vessels in the lesions showed damage involving endothelial destruction and thrombosis. Larger vessels within the lesions were observed with intact vessel walls, surrounded by a rim of vital hepatocytes. In the human samples, tumor-infiltrating lymphocytes were reduced (CD3+ cells: 8.4 +/- 3.7/10 high-power fields (HPF); CD4+ cells: 4.2 +/- 1.9/10 HPF), whereas the number of histiocytes was found to be increased (CD68+ cells: 15.5 +/- 9.02/10 HPF). The recognition of thermofixation and the process of resorption of the RFA lesion is important for the interpretation of biopsies and surgical resection specimens.

MDCT evaluation of injuries after tram accidents in pedestrians.

Multidetector computed tomography (MDCT) is especially suited for emergency diagnostics in multiple trauma patients. The objectives of this study were to investigate the types and frequencies of injuries associated with tram accidents in pedestrians. Eighteen consecutive pedestrian patients with multiple traumas after tram accidents were evaluated with MDCT in our Level I Trauma Center. The mean age in our patient cohort was 36.9 years with a range from 14-92 years. There was a trend for accident events occurring more commonly during the winter months in middle-aged men, often under the influence of alcohol. Patients were divided into two groups with unilateral or complex injury patterns. In both groups, leading diagnoses were head (83.3%) and thorax injuries (66.6%). Abdominal injuries (44.4%) were less common and mainly found in the complex injuries group. The most serious injuries occurred in the complex injuries group when the victim was caught under or between tramcars. A wide range of injuries is associated with tram accidents in pedestrians, which can be classified into two main injury patterns, unilateral and complex. The life-limiting injuries in this setting involved the head with a mortality rate of 22.2% (four patients) in our cohort.

Computed tomography measurements of the lumbar spinous processes and interspinous space.

PURPOSE: This study examines the anatomic proportions of the interspinous space and the spinous processes, considering the optimal placement of an interspinous spacer. METHODS: Between January 2008 and December 2009, 565 patients undergoing computed tomography (CT) scans of the abdomen for various reasons were collected retrospectively for the study. Using the CT scan data, spinous processes of the lumbar spine L1-5 and the interspinous spaces T12-L5 were measured. RESULTS: The average measured interspinous space was 9.1 ± 2.5 mm. This space became significantly (p < 0.001) smaller from anterior to posterior. Average cortical thickness of all lumbar spinous processes was 2.5 ± 0.5 mm. Cortical thickness decreased significantly (p < 0.001) from anterior to posterior. The cortex of the spinous processes from L2 (2.67 ± 0.45 mm) and L3 (2.66 ± 0.94 mm) was significantly thicker (p < 0.001) than that of the others. The spinous process of L5 had the thinnest (p < 0.001) cortex (2.10 ± 0.41 mm), as well as the smallest (p < 0.001) volume (3.0 ± 1.0 ml) and the shortest (p < 0.001) height (16.6 ± 3.6 mm). CONCLUSIONS: The spinous processes of L2 and L3 are the largest and sturdiest, and that of L5 is the weakest. The L4/5 segment features the smallest interspinous space with the thinnest cortex of all lumbar spinous processes. Because the interspinous space narrows posteriorly and the cortex is thicker anteriorly, it seems that the best anatomic position for a stand alone interspinous spacers is anterior.

Association of genetic variants of methionine metabolism with methotrexate-induced CNS white matter changes in patients with primary CNS lymphoma.

Methotrexate (MTX) is an important anticancer drug and the most efficient chemotherapy component in primary CNS lymphoma (PCNSL). A typical side effect of intravenous high-dose MTX is the occurrence of confluent CNS white matter changes (WMC). Because MTX directly interferes with methionine metabolism, we analyzed the impact of genetic variants of methionine metabolism on the occurrence of WMC as a model of MTX toxicity. In a retrospective analysis of 68 PCNSL patients treated with MTX-based polychemotherapy with (n = 42) or without (n = 26) intraventricular treatment, 10 genetic variants influencing methionine metabolism were analyzed. Pearson's chi(2) test and multinominal regression analysis were used to define the relevance of these genetic variants for the occurrence of WMC. In this patient sample, the occurrence of WMC was significantly predicted by the TT genotype of methylenetetrahydrofolate reductase c.677C>T (chi(2) = 8.67; p = 0.013; df = 2), the AA genotype of methylenetetrahydrofolate reductase c.1298A>C (chi(2) = 13.5; p = 0.001; df = 2), and the GG genotype of transcobalamin 2 c.776C>G (chi(2) = 19.73; p < 0.001), in addition to male gender (chi(2) = 11.95; p = 0.001). These data strengthen the hypothesis that MTX effects are influenced by methionine metabolism, which may offer new strategies to improve MTX-based therapies.

Early relapses in primary CNS lymphoma after response to polychemotherapy without intraventricular treatment: results of a phase II study.

BACKGROUND: A systemic and intraventricular polychemotherapy regimen (the Bonn protocol) without radiotherapy resulted in durable responses in 75% of patients <60 years with primary CNS lymphoma (PCNSL), but was complicated by a high rate of Ommaya reservoir infections. Here, the efficacy and toxicity of this regimen without intraventricular treatment was evaluated in PCNSL. PATIENTS AND METHODS: From August 2003 to November 2005, 18 patients with PCNSL <60 years (median age, 53 years) were treated in a phase II trial with a high-dose methotrexate (MTX; cycles 1, 2, 4 and 5) and cytarabine (Ara-C; cycles 3 and 6) based systemic therapy including dexamethasone, vinca-alkaloids, ifosfamide and cyclophosphamide. RESULTS: Study accrual was prematurely stopped in November 2005 due to a high rate of early relapses. Seventeen of 18 patients were assessable for response: nine (53%) achieved complete response (CR), two (12%) complete response/unconfirmed (CRu) and two (12%) partial response (PR); four (24%) showed progressive disease (PD). One treatment was stopped due to toxicity. Median follow-up was 23 months, median response duration was only 10 months in responding patients, and median time to treatment failure (TTF) was 8 months in the whole group. Median overall survival (OS) has not been reached. Systemic toxicity was mainly hematologic. CONCLUSIONS: In PCNSL patients <60 years, polychemotherapy without intraventricular treatment results in a high response rate, but is associated with early relapses in the majority of cases. This is in contrast to the results achieved with the same protocol but with intraventricular treatment.

Which parameters are needed for targeting a multitined radiofrequency device--an approach to a simple algorithm.

BACKGROUND: The use of radiofrequency ablation (RFA) for treatment of liver malignancies is limited by the high rate of local recurrences. The aim of this experimental study was to evaluate parameters describing the reproducible target volume of a RFA procedure in order to facilitate better applicator placement. MATERIALS AND METHODS: RFA was performed in perfused and nonperfused pig livers. The following parameters were measured: axial and transverse diameter, front margin, coagulation center, diameter of sphere ablated (D(S)), distance to center (DC), and volume. Graphic overlays were utilized to visualize variability. Parameters were evaluated for Rita XL (2 algorithms), LeVeen, and Rita Xli applicators. RESULTS: The best prediction of a reproducibly ablated target volume can be made by the diameter of the sphere ablated and the distance of the applicator tip to center of the sphere (DC). The spheres were significantly different in diameter (D(S)) depending on the applicator Rita XL 29 +/- 6 mm, Rita XL(wet) 35 +/- 5 mm, LeVeen 35 +/- 8 mm, Rita Xli 44 +/- 5 mm (perfused livers, p < 0.001). Graphic overlay demonstrated differences in variability that can influence the reliability of the system. CONCLUSIONS: D(S) and DC as specific values for each applicator and algorithm facilitate a placement of the applicator relative to the target volume that maximizes the chance of complete ablation.

Real-time MR-guided wire localization of breast lesions by using an open 1.0-T imager: initial experience.

The purpose of this study was to prospectively evaluate technique and time factors for real-time magnetic resonance (MR) imaging-guided wire localization of suspicious breast lesions by using an open 1.0-T MR imager. It was conducted with institutional review board approval; informed consent was given by patients. Needle placement was monitored in 30 women (mean age, 50.5 years; range, 28-70 years) by using a dynamic balanced gradient-echo (single-shot turbo field-echo [TFE]) sequence with a temporal resolution of 0.5 second. In all patients, the tip of the needle was clearly identified during placement. Consistent with balanced TFE (BTFE) imaging, diagnostic MR imaging after the interventional procedure confirmed that the hookwires were placed 0-6 mm (mean, 3.3 mm) from the target lesions. The total procedure time ranged from 16-36 minutes. Results show that real-time MR-guided wire localization permits correction of the needle position during placement and reduces the interventional procedure time.