External Validation of a Model for Persistent Perfusion Deficit in Patients With Incomplete Reperfusion After Thrombectomy: EXTEND-PROCEED.

BACKGROUND AND OBJECTIVES: We recently developed a model (PROCEED) that predicts the occurrence of persistent perfusion deficit (PPD) at 24 hours in patients with incomplete angiographic reperfusion after thrombectomy. This study aims to externally validate the PROCEED model using prospectively acquired multicenter data. METHODS: Individual patient data for external validation were obtained from the Endovascular Therapy for Ischemic Stroke with Perfusion-Imaging Selection, Tenecteplase versus Alteplase Before Endovascular Therapy for Ischemic Stroke part 1 and 2 trials, and a prospective cohort of the Medical University of Graz. The model's primary outcome was the occurrence of PPD, defined as a focal, wedge-shaped perfusion delay on 24-hour follow-up perfusion imaging that corresponds to the capillary phase deficit on last angiographic series in patients with

The Use of a Commercially Available Endovascular Filter Catheter (Capturex®) for Thoracic Endovascular Aortic Repair (TEVAR) in a Patient with a Coral Reef Aorta.

Due to the risk of mobilizing plaque fragments, transfemoral TEVAR is a potentially dangerous procedure in patients with a coral reef aorta. We describe a practical method for transfemoral TEVAR in a patient with a degenerative thoracic aneurysm and a coral reef aorta. After placing a filter catheter in the abdominal aorta via a contralateral percutaneous femoral access, a working channel through the distal thoracic aorta was created with a balloon-expandable stent graft in the coral reef segment. Thereafter, transfemoral TEVAR could be performed successfully, without any complications. The additional use of a percutaneously placed filter catheter potentially allows reduction of peripheral embolism and hence may prevent patients from more invasive treatment.

Volume Computed Tomography Perfusion Imaging: Evaluation of the Significance in Oncologic Follow-up of Metastasizing Renal Cell Carcinoma in the Early Period of Targeted Therapy - Preliminary Results.

INTRODUCTION: The aim of this study was to assess the significance of volume computed tomography perfusion imaging of metastasizing renal cell carcinoma (mRCC) in the early period after the initiation of targeted therapy. METHODS: Blood flow (BF), blood volume, and clearance (CL) were calculated in 10 patients with histologically verified mRCC before and 1 month after initiation of targeted therapy using compartmental analysis algorithms. In addition, the longest diameter of tumor was measured for both time points and compared. Correlation test was performed between perfusion parameters and size changes with time to progression (TTP). RESULTS: Blood flow and CL were significantly lower after therapy initiation, whereas blood volume and the long diameter remained unchanged. Median values before and after 4 weeks of therapy were 144.2 versus 99.4 mL/min/100 mL for BF (P = 0.009) and 115.5 versus 46.8 mL/min/100 mL for CL (P = 0.007). Changes in BF and CL showed very strong negative correlation with TTP (r = -0.838, P = 0.009 and r = -0.826, P = 0.011, respectively). CONCLUSIONS: Our preliminary study results indicate that volume computed tomography perfusion may assess targeted therapy response of mRCC earlier than the currently used Response Evaluation Criteria in Solid Tumors. In addition, changes in BF and CL may be a promising parameter for prediction of TTP.

Placement of hemoparin-coated stents in the iliac arteries: early experience and midterm results in 28 patients.

PURPOSE: Aim was to determine immediate results and mid-term outcome of the hemoparin-coated (HC) stainless-steel stent (camouflage coating) in the treatment of occlusive lesions of the iliac arteries. MATERIALS AND METHODS: Twenty-eight patients were prospectively treated with the use of a HC stent between January 2007 and March 2010. Clinical examination and color-doppler ultrasound were performed at 1, 3, 6 and 12 months, CT angiography (CTA) or MR angiography (MRA) at 12 months. Indication for treatment was a high-grade stenosis of the common iliac and/or external iliac artery. RESULTS: Successful placement was achieved in all patients. Significant decrease in translesional pressure gradient (>10 mm Hg) was measured in 27 patients (96%). In one patient, proximal dissection occurred without flow limitation. A minor complication (small access site hematoma) occurred in one patient (4%). Two patients (7%) were lost to follow-up. After 12 months, stent patency in CTA, MRA and ultrasound was 100%. 20 patients (77%) experienced an initial improvement of at least one clinical stage. In one patient (4%), mild intimal hyperplasia without significant stenosis was observed. In three patients (12%), proximal or distal stenosis occurred. A non-significant increase of mean ankle-brachial index (ABI) after treatment was measured (0.85 ± 0.27 vs. 0.75 ± 0.22, respectively; p=0.328). CONCLUSIONS: The use of HC stents in patients with iliac artery occlusive disease may lead to a lower rate of intimal hyperplasia and thus to increased patency rates even in heavily calcified vessels. However, large-scale prospective trials have to be performed to evaluate the long-term patency rates of the HC coated stents.

Acute pulmonary embolism: comparison of standard axial MDCT with paddlewheel technique.

PURPOSE: The purpose of this study was to evaluate the ability of rotated paddlewheel reformations for the detection of central and peripheral pulmonary embolism (PE) compared to standard axial multi detector CT (MDCT) images. MATERIAL AND METHODS: CT scans of 35 patients with PE were reviewed by three independent readers for the detection of pulmonary emboli using standard axial CT scans and reformatted paddlewheel technique. All images were evaluated in random order. MDCT examinations were performed with a collimation of 1.25 mm, a pitch of six and a reconstruction interval of 0.8mm. For each patient MIP were reformatted by using a paddlewheel arrangement with 5mm slab thickness and 5 degrees rotation. Standard of reference for PE was a consensus reading of the axial images by all three readers. RESULTS: The overall sensitivity for the axial images for the three readers ranged between 91% and 96%; for paddlewheel reformations from 78% to 83%; the specificity for both methods was 98-99%. Inter- and intraobserver agreement was also higher for axial images than for paddlewheel reformations. CONCLUSION: Comparing standard axial MDCT scans and reformatted paddlewheel images no significant difference for the detection of central PE was found, whereas for the detection of peripheral emboli standard axial images showed a significant higher percentage of detecting PE than paddlewheel reformations.

Endoluminal therapy in patients with peripheral arterial disease: prospective assessment of quality of life in 190 patients.

OBJECTIVE: The objective of our study was to assess the impact of endoluminal treatment on health-related quality of life in patients with peripheral arterial disease. SUBJECTS AND METHODS: Changes in quality of life were prospectively evaluated in 190 patients before and 1, 3, 6, and 12 months after treatment. Physical, emotional, and general health components were determined using the short-form (36 items) health survey (SF-36). Claudicant patients were compared with patients who had critical limb ischemia. The influence of the lesion location (iliac, femoropopliteal, or crural) restenosis, and additional interventions on quality of life were evaluated. RESULTS: Six- and 12-month follow-up data were available for 136 and 103 patients, respectively. Significant improvements in quality of life were observed in most of the patients after the intervention. Many of the SF-36 scores decreased from the 6- to the 12-month follow-up but remained significantly higher than the score before the intervention. Reduction of bodily pain was the most evident effect of treatment. Claudicant patients seemed to benefit more from treatment than patients with critical limb ischemia. In terms of SF-36 scores, percutaneous transluminal angioplasty of the crural arteries was equally as effective as endoluminal revascularization of the iliac and femoropopliteal arteries and multilevel interventions were as effective as single-level interventions. The occurrence of a restenosis was significantly related to lower SF-36 scores, and restenosis not followed by a second intervention was associated with lower SF-36 scores. CONCLUSION: Although there were several differences between the groups, significant improvements in quality of life up to 12 months after endoluminal therapy were observed in most patients.

MDCT angiography of the pulmonary arteries: influence of body weight, body mass index, and scan length on arterial enhancement at different iodine flow rates.

OBJECTIVE: The purpose of this study was to assess whether body weight, body mass index, and scan length influence arterial enhancement during CT angiography (CTA) of the pulmonary arteries at different iodine flow rates. MATERIALS AND METHODS: CTA examinations of the pulmonary arteries performed for routine clinical care of 120 patients between March and December 2003 were retrospectively evaluated. Patients had received either 120 mL of contrast medium with an iodine concentration of 300 mg I/mL (group A) or 90 mL of contrast medium with an iodine concentration of 400 mg I/mL (group B). The iodine dose was 36 g, and the injection rate was 4 mL/s in all examinations. The iodine flow rate was 1.2 g I/s in group A and 1.6 g I/s in group B. Arterial attenuation along the z-axis was measured per patient, and the influence of body weight, body mass index, and scan length on enhancement of the pulmonary arteries in the two groups was assessed. RESULTS: In group A and in group B, body weight and body mass index correlated significantly with mean enhancement along the z-axis (r = -0.35 and -0.26 for group A and -0.48 and -0.40 for group B). Scan length showed no correlation with pulmonary attenuation. Mean pulmonary artery enhancement was significantly higher in group B with a difference of 51 H compared with group A. CONCLUSION: Pulmonary artery attenuation in CTA of the pulmonary arteries shows a small but significant correlation with body weight and body mass index independently of the iodine flow rate used. A higher iodine flow rate improves pulmonary artery enhancement.

Psoriatic arthritis and rheumatoid arthritis: findings in contrast-enhanced MRI.

OBJECTIVE: Our objective was to define typical MRI findings of the wrist and the hand in patients with psoriatic arthritis (PsA) and rheumatoid arthritis (RA). MATERIALS AND METHODS: Eighteen PsA and 21 RA patients with arthralgia of the wrist or hand joints underwent gadolinium-enhanced MRI of the wrist and hand. Two experienced radiologists interpreted abnormalities in consensus with respect to periarticular soft-tissue swelling, synovitis with or without effusion, periostitis, bone edema, bone erosions, bone cysts, and tenosynovitis. The distribution of the abnormalities also was evaluated. RESULTS: Erosions were statistically more frequent in patients with RA (p < 0.05). Periostitis was statistically seen more frequently in patients with PsA (p < 0.05). No statistically significant difference was found in the frequency of synovitis, bone marrow edema, bone cysts, and tenosynovitis between the two groups (p > 0.05). The radiocarpal joint, the midcarpal joints, the carpometacarpal joints, and the metacarpophalangeal joints were significantly affected more frequently in patients with RA than in patients with PsA (p < 0.05), whereas the proximal interphalangeal joints were significantly more frequently affected in patients with PsA (p < 0.05). CONCLUSION: Periostitis and synovitis of the proximal interphalangeal joints are typical MRI findings in patients with PsA, whereas synovitis with erosions of the wrist, the midcarpal joints, the carpometacarpal joints, and the metacarpophalangeal joints are typical findings in patients with RA.

Routine use of three-dimensional contrast-enhanced moving-table MR angiography in patients with peripheral arterial occlusive disease: comparison with selective digital subtraction angiography.

PURPOSE: To compare the diagnostic accuracy of contrast-enhanced (CE) three-dimensional (3D) moving-table magnetic resonance (MR) angiography with that of selective digital subtraction angiography (DSA) for routine clinical investigation in patients with peripheral arterial occlusive disease. METHODS: Thirty-eight patients underwent CE 3D moving-table MR angiography of the pelvic and peripheral arteries. A commercially available large-field-of-view adapter and a dedicated peripheral vascular phased-array coil were used. MR angiograms were evaluated for grade of arterial stenosis, diagnostic quality, and presence of artifacts. MR imaging results for each patient were compared with those of selective DSA. RESULTS: Two hundred and twenty-six arterial segments in 38 patients were evaluated by both selective DSA and MR angiography. No complications related to MR angiography were observed. There was agreement in stenosis classification in 204 (90.3%) segments; MR angiography overgraded 16 (7%) segments and undergraded 6 (2.7%) segments. Compared with selective DSA, MR angiography provided high sensitivity and specificity and excellent interobserver agreement for detection of severe stenosis (97% and 95%, kappa = 0.9 +/- 0.03) and moderate stenosis (96.5% and 94.3%, kappa = 0.9 +/- 0.03). CONCLUSION: Compared with selective DSA, moving-table MR angiography proved to be an accurate, noninvasive method for evaluation of peripheral arterial occlusive disease and may thus serve as an alternative to DSA in clinical routine.

Density histogram analysis of unenhanced hepatic computed tomography in patients with diffuse liver diseases.

OBJECTIVE: The aim of the study was to assess the potential of density histogram analysis of unenhanced hepatic computed tomography (CT) in the diagnosis and differentiation of diffuse liver diseases. METHODS: Twenty-six patients with normal liver parenchyma, 35 patients with diffuse steatosis, 14 patients with acute steatohepatitis, 15 patients with active alcoholic cirrhosis, 23 patients with inactive alcoholic cirrhosis, 15 patients with virus-induced cirrhosis, and 8 patients with hemochromatosis underwent unenhanced hepatic CT. All diffuse liver diseases and the absence of diffuse liver disease were histologically proven. Quantitative analysis of unenhanced liver parenchyma was performed in each patient. RESULTS: The hepatic density histogram showed no significant differences in kurtosis and skewness between the groups (P > 0.05). Except for steatosis, active alcoholic cirrhosis, and hemochromatosis, diffuse liver diseases led to similar densities of liver parenchyma in unenhanced hepatic CT. CONCLUSION: A reliable diagnosis and differentiation of diffuse liver diseases on the basis of density histogram analysis is not possible.

Multiphasic multidetector-row CT (MDCT) in detection and staging of transitional cell carcinomas of the upper urinary tract.

The aim of this study was to evaluate the potential of multiphasic multidetector-row CT (MDCT) in the detection and staging of transitional cell carcinomas (TCC) of the upper urinary tract. We performed a retrospective chart review of 39 consecutive patients with 41 histologically verified TCC of the renal pelvis and/or the ureter. The urinary tract was examined using MDCT performing unenhanced and contrast-enhanced scans during the corticomedullary (CMP), nephrographic (NP) and pyelographic phase (PP). Tumors were staged according to the TNM classification. MDCT and histopathological findings were correlated. The attenuation of the lesions was documented in Hounsfield units (HU). In MDCT, all 41 TCC--including two multicentric TCC--were detected. TCC confined to the organ (stage 0a-II) was correctly staged in 28/29 tumors (96.6%). Stage III-IV tumors were correctly staged in 8/12 patients (66.6%). Overall, MDCT was accurate in predicting pathologic TNM stage in 36/41 upper urinary tract TCC (87.8%). There was no significant difference of mean attenuation of TCC between CMP, NP and PP (P > 0.05). MDCT with its high spatial and temporal resolution is an accurate tool for detection TCC of the upper urinary tract, with 87.8% accuracy in predicting its stage.

High-concentration contrast media in multiphasic abdominal multidetector-row computed tomography: effect of increased iodine flow rate on parenchymal and vascular enhancement.

OBJECTIVE: The purpose of this study was to assess the influence of the iodine flow rate on parenchymal and vascular enhancement during multiphasic abdominal multidetector-row computed tomography (MDCT). METHODS: Fifteen patients underwent MDCT at an iodine flow rate of 1.2 g/s as well as 1.6 g/s (group A, protocols 1 and 2), and 90 patients underwent MDCT at an iodine flow rate of 1.2 g/s (group B) or 1.6 g/s (group C). Measurements were performed for all groups in the liver, spleen, pancreas, portal vein, inferior vena cava, and abdominal aorta. RESULTS: Aortal and pancreatic enhancement during the arterial phase was significantly higher with the higher iodine flow rate. The mean difference in aortal enhancement was 60 Hounsfield units (HU) between protocols 1 and 2 of group A, and the mean difference was 70 HU between groups B and C. The mean difference in pancreatic enhancement was 10 HU between protocols 1 and 2 of group A and 17 HU between groups B and C. During the portal and hepatic venous phases, no significant difference in enhancement was observed. CONCLUSION: A high iodine flow rate in multiphasic abdominal MDCT improves enhancement of the aorta and the pancreas during the arterial phase but does not influence later phases.

MDCT angiography of the pulmonary arteries: influence of iodine flow concentration on vessel attenuation and visualization.

OBJECTIVE: Our objective was to assess the influence of iodine flow concentration on attenuation and visualization of the pulmonary arteries in thoracic MDCT angiography. MATERIALS AND METHODS: One hundred consecutive patients who were referred to our department with suspected acute pulmonary embolism underwent MDCT angiography of the pulmonary arteries either with 120 mL of standard contrast medium (300 mg I/mL) (group A) or with 90 mL of high-concentration contrast medium (400 mg I/mL) (group B). The contrast medium was injected at a flow rate of 4 mL/sec. The scan delay was determined using a semiautomatic bolus-tracking system in all examinations conducted with the same scanning parameters. Quantitative analysis was performed by region-of-interest measurements along the z-axis to compare the attenuation profiles of the two groups. Attenuation of the fourth-, fifth-, and sixth-order arteries was assessed visually for differences between the two groups. RESULTS: The mean enhancement along the z-axis was 268 +/- 56 H in group A and 344 +/- 108 in group B. The difference of 76 H was statistically significant (p < 0.001). The attenuation profile was similar in both groups. The detection rate of fifth- and sixth-order arteries was significantly higher in group B than in group A (94% compared with 91% and 72% compared with 60%, respectively, p < 0.01). CONCLUSION: Use of a high flow concentration of iodine in MDCT angiography of the pulmonary arteries significantly increases attenuation of the pulmonary arteries, thereby improving visualization of subsegmental pulmonary arteries.

Frequency and significance of lumbar and inferior mesenteric artery perfusion after endovascular repair of abdominal aortic aneurysms.

PURPOSE: To evaluate the frequency and influence of perfused side branches (lumbar arteries [LA] and inferior mesenteric artery trunks) on development of type II endoleaks (EL-II) and on volume changes of abdominal aortic aneurysms (AAA) after endovascular repair. METHODS: Of 114 patients undergoing EVR of AAA, 89 patients (83 men; mean age 72+/-7.5 years, range 51-88) with >6 months' follow-up and no type I endoleaks were retrospectively analyzed to determine any relationships between retrograde perfusion, endoleaks, and sac volume. Data were derived from computed tomographic angiographic (CTA) scans taken before and after intervention, at discharge, and at 1, 3, 6, and semi-annually thereafter in follow-up. Two groups were identified and compared based on their status at 6 months post EVR: without perfused side branches (group 1) and with perfused collaterals (group 2); group 2 was further divided according to the absence (2a) or presence (2b) of endoleak. RESULTS: Median follow-up was 24 months (range 6-36). Based on a total of 582 CTAs analyzed, 17 (19%) patients developed type II endoleaks (EL-II) during follow-up. There was a significant difference in the number of perfused LAs prior to EVR between groups 1 (n=44) and the 45 patients with postprocedural patent collateral arteries in group 2 (p<0.05); there was no significant difference between groups 2a and 2b (p=0.88) relative to the number of pre-existing patent collaterals. The number of pLAs preoperatively and the rate of type II endoleak were significantly correlated (p<0.05). No type II endoleak was seen in patients without perfused side branches (p=0.01). No significant differences in mean volumes were found between groups 1 and 2a (no EL-II), but significant differences between groups 1 and 2b were seen in later follow-up. CONCLUSIONS: A larger number of patent LAs before EVR was associated with a significantly higher rate of type II endoleak. Patent collateral vessels were common after aneurysm repair, but the frequency decreased during follow-up. Persistent side branch perfusion was associated with increased type II endoleak after endovascular AAA repair. Significant differences in volume changes in later follow-up were seen between patients with or without type II endoleak.

Aortoiliac enhancement during computed tomography angiography with reduced contrast material dose and saline solution flush: influence on magnitude and uniformity of the contrast column.

RATIONALE AND OBJECTIVES: To compare the magnitude and uniformity of aortoiliac contrast enhancement obtained from uniphasic contrast material injections versus contrast material injections with reduced iodine dose followed by a saline flush in aortoiliac multislice CT angiography (CTA). METHODS: Twenty-nine patients with abdominal aortic aneurysms underwent aortoiliac CTA using protocols A and B. With protocol A, 120 mL contrast material (300 mgI/mL), and with protocol B, 100 mL contrast material followed by a 40-mL saline solution flush were administered at a flow rate of 4 mL/s. Quantitative analysis was performed by calculating mean aortoiliac attenuation, mean plateau deviation, and mean difference between maximum and minimum attenuation value for both groups. Qualitative analysis was performed by visual assessment of vascular enhancement using 2-dimensional and 3-dimensional postprocessing techniques. RESULTS: The mean aortoiliac attenuation with protocol A was 291 +/- 62 HU, and with protocol B it was 285 +/- 61 HU. The difference of 6 HU was not statistically significant (P = 0.27). Mean plateau deviation was significantly smaller using protocol A than protocol B (16 +/- 9 HU vs. 20 +/- 10 HU, P = 0.03). In addition, the mean difference between maximum and minimum attenuation value was significantly smaller with protocol A than with protocol B (59 +/- 29 HU vs. 72 +/- 32 HU, P = 0.01). Visual analysis showed no difference in contrast material magnitude and homogeneity between the protocols. CONCLUSIONS: In aortoiliac CTA, a saline solution flush after contrast material bolus allows an iodine dose reduction of approximately 20 mL without impairing the magnitude of contrast enhancement but degrades the uniformity of the contrast column. However, the degradation does not affect visual analysis.

Improvement of parenchymal and vascular enhancement using saline flush and power injection for multiple-detector-row abdominal CT.

The aim of this study was to determine if a saline solution flush following low dose contrast material bolus improves parenchymal and vascular enhancement during abdominal multiple detector-row computed tomography (MDCT). Forty-one patients (24 men and 17 women; mean age 49 years, age range 27-86 years) underwent abdominal MDCT (collimation 4x5 mm, 15-mm table increment, reconstruction interval 5 mm, gantry rotation period 0.8 s) with a single- as well as with a double syringe power injector. Indication for examination were benign and malignant tumors and inflammatory diseases. Patients received 100 ml nonionic contrast material (300 mgI/ml) alone or pushed with 20 ml saline solution. Mean enhancement values for both protocols were measured in the liver, the spleen, the pancreas, the renal cortex, the portal vein, the inferior vena cava and the abdominal aorta. Double syringe power-injector protocol led to significantly higher parenchymal and vascular enhancement than single syringe power-injector protocol (p<0.05). The improvement in mean enhancement of the liver was 9 +/- 9 HU, of the spleen 8 +/- 10 HU, of the pancreas 7 +/- 9 HU, and of the renal cortex 8 +/- 20 HU. The improvement in mean enhancement of the portal vein was 10 +/- 17 HU of the inferior vena cava 8 +/- 13 HU and of the abdominal aorta 10 +/- 17 HU. The use of a double syringe power injector with saline flush following contrast material bolus significantly improves parenchymal and vascular enhancement during contrast-enhanced abdominal MDCT with low iodine doses.

Abdominal multidetector row computed tomography: reduction of cost and contrast material dose using saline flush.

OBJECTIVE: To evaluate the potential of a saline solution flush after the contrast material bolus in abdominal multidetector row CT (MDCT) in contrast material dose and cost reduction. METHODS: Abdominal MDCT was performed in 78 patients who were assigned randomly to 2 groups receiving 120 mL nonionic contrast material (300 mgI/mL) alone or 100 mL of the same contrast material pushed with 40 mL of saline solution. Mean attenuation values for both groups were measured in the liver, the spleen, the pancreas, the portal vein, the inferior vena cava, and the abdominal aorta. Cost analyses were performed for both groups. RESULTS: There was no significant difference in parenchymal and vascular enhancement between both groups. The difference of the enhancement was 2 HU for the liver (P = 0.11), 2 HU for the spleen (P = 0.44), 3 HU for the pancreas (P = 0.38), 9 HU for the portal vein (P = 0.11), 3 HU for the inferior vena cava (P = 0.55), and 10 HU for the aorta (P = 0.06). Taking the costs of contrast material, saline solution, and disposal material into account, 7.30 dollars was saved by the patient using a saline solution flush. CONCLUSIONS: Using a saline flush after the contrast material bolus in abdominal MDCT allows an iodine dose reduction of approximately 6 g, or 17%, without impairing mean parenchymal and vascular enhancement and a cost reduction of 7.30 dollars per patient.

Value of a blood pool contrast agent in MR venography of the lower extremities and pelvis: preliminary results in 12 patients.

The purpose of this study was to determine the value of a blood-pool contrast media (NC100150, Nycomed Imaging (now Amersham Health) Oslo, Norway) for evaluation of venous thrombosis of the deep veins of the pelvis and lower extremities. Twelve patients were prospectively evaluated with conventional X-ray venography (XRV) and MR venography (MRV) after injection of NC100150 (2 ml/kg body weight). The source images and 3D maximum intensity projection (MIP) were viewed on an independent workstation. Diagnosis was made in consensus from two radiologists. Diagnostic image quality was achieved in 87 veins with XRV and MRV. As determined by XRV, thrombus was present in 30 out of 87 veins (34.5%). There was agreement concerning absence or presence of thrombi in 83 out of 87 veins (95.4%; kappa = 0.9 +/- 0.05). Compared to XRV, overall sensitivity and specificity of blood-pool MRV were 93.3% and 96.5%, respectively. Two venous thromboses of the popliteal and posterior tibial vein were diagnosed in MRV, but not in XRV. Conversely, two venous thromboses below the knee had been missed by MRV. NC100150 allows prolonged and improved visualization of the peripheral vasculature and may overcome some limitations of gadolinium contrast media. A more complete examination of the proximal venous tree may be possible than with conventional XRV. Arterial and venous enhancement and motion artifacts can limit image interpretation.

Early experience and midterm follow-up results with a new, rotational thrombectomy catheter.

PURPOSE: To assess the efficacy and safety of the Rotarex rotational thrombectomy catheter in treating occlusions of the femoropopliteal arteries. METHODS: The Rotarex catheter (Straub Medical, Switzerland) is a rotational thrombectomy device which is supposed to be able to remove fresh and partially organized clot material from an acutely or subacutely occluded vessel. Nineteen limbs of 18 patients (10 women, 8 men; mean age 72.9 +/- 7.3 years) with acute or subacute (23 +/- 16 days) occlusions of the middle or distal third of the superficial femoral artery or the popliteal artery were treated. The occlusions were 3-20 cm long. RESULTS: Thrombectomy was technically successful in 15 of 19 vessels (79%). The primary procedural success including additional procedures such as angioplasty and/or stent-graft placement in 17 limbs was 94%. The mean ankle-brachial index improved from 0.36 +/- 0.26 (before thrombectomy) to 0.81 +/- 0.21 (2 days after the procedure) (p = 0.012). Clinical symptoms shifted to at least one Fontaine stage lower in 13 limbs. As complications we observed two perforations (arteries showing heavily calcified plaques), one arteriovenous fistula and three distal embolizations. One perforation, the fistula and one intimal tear after percutaneous transluminal angioplasty were treated with covered stents; the three distal embolizations were treated successfully with aspiration or Rotarex thrombectomy. In the other perforation the intervention was terminated. None of the complications needed surgical treatment. The complication rate was 31.5%. Follow-up studies showed three early (4-11 days) and six late (1-6 months) reocclusions. The cumulative primary patency rate was 68 +/- 12% at 3 months, and 39 +/- 13% at 6, 12 and 19 months; the secondary patency rate was 68 +/- 12% at 3 months and 53 +/- 13% at 6, 12 and 20 months. CONCLUSION: The Rotarex thrombectomy catheter is effective and quick in treating acute and subacute occlusions of the superficial femoral and popliteal arteries. It should not be used in arteries with heavily calcified plaques because of the risk of perforation. Limited long-term patency is mainly due to the complexity of the underlying lesion. Our results suggest that the Rotarex mechanical thrombectomy catheter is effective and might serve as an alternative treatment modality to intra-arterial lysis.