Philipp J Schaefer

Universitätsklinikum Schleswig - Holstein, Kiel, Schleswig-Holstein, Germany

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Publications (21)60.05 Total impact

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    ABSTRACT: The hypothesis that endovascular treatment with covered stents has equal risks but higher efficacy than BMS in long femoro-popliteal artery disease was tested. While endovascular treatment of short SFA lesions revealed excellent results, efficacy in long lesions remains unsatisfactory. In a prospective, randomized, single-blind, multicenter study 141 patients with symptomatic PAD were assigned to treatment with heparin-bonded, covered stents (VIABAHN®, 72 patients) or BMS (69 patients). Clinical outcomes and patency rates were assessed at 1, 6, and 12-months. Mean lesion length was 19.0±6.3cm versus 17.3±6.6cm in the VIABAHN® versus BMS group. Major complications within 30-days were observed in 1.4%. The 12-months primary patency rates in the VIABAHN® and BMS group were: ITT 70.9% (95%CI, 0.58-0.80) and 55.1% (95%CI, 0.41-0.67; log rank p=0.11), TPP 78.1% (95%CI, 0.65-0.86) and 53.5% (95%CI, 0.39-0.65) (HR 2.23, 95%CI, 1.14-4.34; log rank p=0.009). In lesions ≥20cm (TASC D) the 12-months patency rate was significantly longer in VIA patients in the ITT-analysis (VIA 71.3% versus BMS 36.8%; p=0.01) and the TPP-analysis (VIA 73.3% versus BMS 33.3%; p=0.004). Freedom from target lesion revascularization was 84.6% for VIABAHN® (95%CI, 0.72-0.91) versus BMS 77.0% (95%CI, 0.63-0.85; p=0.37). The ankle-brachial index in the VIABAHN® group significantly increased to 0.94±0.23 (versus BMS 0.85±0.23; p<0.05) at 12-months. This randomized trial in symptomatic PAD patients who underwent endovascular treatment for long femoro-popliteal lesions demonstrated significant clinical and patency benefits for heparin-bonded covered stents compared to BMS in lesions ≥20cm and for all lesions in the TPP analysis. In the ITT analysis for all lesions, which however was diluted by 8.5% major protocol violations, the difference was not significant (Reg.Nr. ISRCTN48164244). Clinical trial ID: VIASTAR; http://www.controlled-trials.com/ISRCTN48164244; ISRCTN48164244.
    Journal of the American College of Cardiology 07/2013; · 14.09 Impact Factor
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    ABSTRACT: Background Breast cancer screening programs have been established worldwide and early detection of breast cancer has increased steadily. The most common way to confirm dignity of non-palpable and sonographically-occult suspicious findings on mammography is the stereotactically-guided vacuum-assisted breast biopsyPurposeTo compare two stereotactically guided vacuum-assisted breast biopsy systems measuring time effectiveness and quality of harvested material in clinical practice.Material and Methods One hundred and forty-six patients presenting with suspicious microcalcifications on mammography were included in the study. Biopsies were carried out with either the Mammotome(®) system (11-gauge and 8-gauge) or the ATEC(®) system (12-gauge and 9-gauge). Lesions with a diameter <15 mm on mammography were biopsied with 11-gauge or 12-gauge devices whereas lesions >15 mm were targeted with 8-gauge and 9-gauge. Mammotome(®) system 8-gauge device was used in 34 patients, the 11-gauge system in 37 patients. The ATEC(®) system 9-gauge system was used in 37 patients and 12-gauge in 38 patients. Time was taken, focusing on preparing the system, time of collecting the samples, preparing the samples, and cleaning the site. During the biopsies 24 samples were taken. The histologic quality of the tissue samples was judged by a pathologist in a blinded fashion according to a specimen grading classification concerning tissue fragmentation, artefacts, and the adequacy of the tissue for diagnosis.ResultsThe median overall time for the Mammotome(®) system was 879 s (11-gauge) and 934 s (8-gauge) and for the ATEC(®) system 671 s (12-gauge) and 673 s (9-gauge). The ATEC(®) system displays a significantly shorter overall time for small and large biopsy devices (U-test, P < 0.001). Concerning the mean time difference of the overall time comparing small and large systems the ATEC(®) system was 267.6 s faster using the small and 244.8 s faster using the large system. Comparing the histologic quality of tissue samples the Mammotome(®) system shows significantly higher values for the large and the small system (Chi-square test, P < 0.001).Conclusion Both biopsy systems meet all requirements for daily practice and confirm the diagnosis of suspicious microcalcifications. The ATEC(®) system was observed to be faster but this difference of about 250 s might not be relevant in daily practice. The Mammotome(®) system provides a better histologic quality of tissue samples.
    Acta Radiologica 01/2013; · 1.33 Impact Factor
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    ABSTRACT: To examine and compare in an ex vivo study different nitinol stent designs intended for the superficial femoral artery (SFA) with regard to the appearance of fracture. Seven different 8-×40-mm nitinol stents were evaluated (Misago, Absolute, Smart, Luminexx, Sentinol, Lifestent NT, and Sinus-Superflex). Finite element analysis (FEA) was used for digitalized stent design comparison; the strain during stent movement was calculated for bending, compression, and torsion. Additional mechanical fatigue tests for bending (70°), compression (40%), and torsion (twisted counterclockwise by 180°) were performed up to 650,000 cycles or until a fracture was observed. The FEA bending test showed that only the Misago, LifeStent, and Absolute stents presented no zones of high strain; in the torsion test, the Smart stent also had no zones of high strain. Macroscopic evaluation after mechanical bending indicated that the LifeStent performed the best (no stent fracture after 650,000 cycles). Misago and Absolute stents showed fractures at 536,000 cycles and 456,667 cycles, respectively (range 320,000-650,000 cycles). After compression and torsion testing, Misago showed no stent fracture after 650,000 cycles. The worst performing stent was Luminexx during all test cycles. The 7 SFA stents showed differences in the incidence of high strain zones, which indicates a potential for stent fracture, as demonstrated by the mechanical fatigue tests. Differences in stent design might play a major role in the appearance of stent strut fracture related to restenosis and reocclusion.
    Journal of Endovascular Therapy 12/2010; 17(6):767-76. · 2.70 Impact Factor
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    ABSTRACT: To evaluate safety and efficacy of cryoplasty versus conventional angioplasty for focal popliteal arterial occlusive disease. Patients with focal atherosclerotic stenoses and occlusions of the popliteal artery were randomized to cryoplasty or conventional angioplasty as the initial treatment strategy. The primary objective was target lesion patency. The secondary endpoint was treatment success without the need for stents. Duplex ultrasonography was performed at 3, 6, 9, and 15 months. Eighty-six patients (mean age, 72 years; age range, 50-94 years) were enrolled in this study. Forty patients were randomized to cryoplasty and 46 to conventional angioplasty. Demographics, risk factors, clinical stage of disease, and lesion details were comparable. On intention-to-treat basis, initial success was 35% for cryoplasty versus 54% for conventional angioplasty (P = .02). The rate of grade C dissection was 35% after cryoplasty and 26% after conventional angioplasty (P = .4). Optional long-term percutaneous transluminal angioplasty (PTA) was performed in 58% of cryoplasty patients. The rate of stent placement for dissection and/or residual stenosis was 30% after cryoplasty (including long-term dilation) and 39% after conventional angioplasty (P = .34). The mean (+/-standard deviation) target lesion patency at 9 months was 79.3% +/- 7.5 for cryoplasty and 66.7% +/-8.1 for conventional angioplasty; however, the results are not significant (P = .14). Cryoplasty of the popliteal artery alone showed a lower anatomic success when compared with conventional angioplasty. Combined with optional long-term PTA, however, stent placement was not needed more often. There was a trend toward higher patency after cryoplasty, but differences were not statistically significant and results of long-term follow-up have to be awaited.
    Journal of vascular and interventional radiology: JVIR 02/2010; 21(2):186-94. · 1.81 Impact Factor
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    ABSTRACT: The purpose was to evaluate ex-vivo a prototype of a novel biopsy canula under CT fluoroscopy-guidance in ventilated porcine lung explants in respiratory motion simulations. Using an established chest phantom for porcine lung explants, n = 24 artificial lesions consisting of a fat-wax-Lipiodol mixture (approx. 70HU) were placed adjacent to sensible structures such as aorta, pericardium, diaphragm, bronchus and pulmonary artery. A piston pump connected to a reservoir beneath a flexible silicone reconstruction of a diaphragm simulated respiratory motion by rhythmic inflation and deflation of 1.5 L water. As biopsy device an 18-gauge prototype biopsy canula with a lancet-like, helically bended cutting edge was used. The artificial lesions were punctured under CT fluoroscopy-guidance (SOMATOM Sensation 64, Siemens, Erlangen, Germany; 30mAs/120 kV/5 mm slice thickness) implementing a dedicated protocol for CT fluoroscopy-guided lung biopsy. The mean-diameter of the artificial lesions was 8.3 +/- 2.6 mm, and the mean-distance of the phantom wall to the lesions was 54.1 +/- 13.5 mm. The mean-displacement of the lesions by respiratory motion was 14.1 +/- 4.0 mm. The mean-duration of CT fluoroscopy was 9.6 +/- 5.1 s. On a 4-point scale (1 = central; 2 = peripheral; 3 = marginal; 4 = off target), the mean-targeted precision was 1.9 +/- 0.9. No misplacement of the biopsy canula affecting adjacent structures could be detected. The novel steerable biopsy canula proved to be efficient in the ex-vivo set-up. The chest phantom enabling respiratory motion and the steerable biopsy canula offer a feasible ex-vivo system for evaluating and training CT fluoroscopy-guided lung biopsy adapted to respiratory motion.
    CardioVascular and Interventional Radiology 12/2009; 33(4):828-34. · 2.09 Impact Factor
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    ABSTRACT: We present a safe and quick technique for crossover embolization procedures of the internal iliac artery with high-profile guiding catheter systems, after a pull-through maneuver with establishment of a crossover catheter-snare system. The attached snare is used to stabilize and direct the guiding catheter.
    CardioVascular and Interventional Radiology 11/2009; 33(3):583-5. · 2.09 Impact Factor
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    ABSTRACT: The purpose of this study was to examine the safety and efficacy of the Frontrunner XP CTO (chronic total occlusion) Catheter (Cordis) for recanalization of long femoropopliteal artery occlusions. A Frontrunner catheter was used to treat 26 CTOs in SFA after guidewire failure (68.3 +/- 8.8 years). Sixty-seven percent of patients had severe claudication. Critical lower limb ischemia with rest pain or minor tissue loss was present in three and eight patients, respectively. All the lesions were considered complex (TASC B, C, and D); 68% of the lesions were heavily calcified. The mean lesion length was 17.6 cm (range, 10-42 cm). The initial attempt to cross the occlusion with the CTO guidewire V18 was unsuccessful in 26 of 76 limbs (34.26%). A secondary attempt using the Frontrunner catheter (crossover approach, 27%; antegrade, 73%) performed in all 26 failed cases was successful in 17 limbs (65.38%), increasing the technical success rate to 88.12%. The main reasons for failure with the Frontrunner were inability to cross the lesion due to heavy calcification (six of nine) and inability to re-enter the true lumen after subintimal passage of the occluded segment (three of nine). The mean fluoroscopy time was 22.9 min. Minor complications included one distal extension of the dissection with involvement of the first popliteal segment and one perforation in the occluded segment. No major complications were seen. In conclusion, recanalization with the Frontrunner CTO catheter is a simple and safe method with a high technical success rate in the endovascular treatment of long superficial femoral artery occlusions and should be an alternative method after guidewire failure.
    CardioVascular and Interventional Radiology 09/2009; 33(1):25-33. · 2.09 Impact Factor
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    ABSTRACT: To evaluate the efficiency of 2 distal filtration devices designed for cerebral protection during carotid angioplasty in an in-vitro bench-top model. After positioning the respective protection devices (RX Accunet and DynaCap) 5 cm distal to the bifurcation, embolization from carotid angioplasty was simulated by injecting polyvinyl alcohol particles in groups of small (150 to 250-microm diameter, approximately 500 particles), medium (250 to 355-microm diameter, approximately 200 particles), and large (700 to 1000-microm diameter, approximately 80 particles). Five milligrams of each group were injected separately into the internal carotid artery (ICA) model proximal to the protection filters. Particles passing the protection devices were caught in 100-microm filters and weighed. For small particles, the amount in the effluent of the ICA was 0.34+/-0.12 mg (6.8%) for the RX Accunet and 0.51+/-0.16 mg (11.2%) for the Occam DynaCap (p<0.05). For the other particle sizes, there was no statistical difference between the filters (p>0.05). In all test runs, neither of the tested devices prevented embolization completely, with approximately 3% to 6% of particles penetrating. For small particles, the lowest amount of particles passing the protection device was achieved using the RX Accunet system.
    Journal of Endovascular Therapy 05/2009; 16(2):161-7. · 2.70 Impact Factor
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    ABSTRACT: To examine and compare different carotid stent designs with regard to flexibility, adaptability (adjustability), conformability (compliance) to the vessel, and scaffolding to reduce plaque prolapse and embolization. Six stents of different design were compared (Precise, Acculink, Protégé, Xact, Wallstent, and Cristallo Ideale). Optical microscopy was used to determine exact dimensions and scaffolding of each stent. Radial force was tested using a parallel plate setup, and flexibility (torsion and bending) was measured in water at body temperature. Particle penetration simulation was performed using plastic spheres from 1.5- to 6.0-mm outer diameter. Stent dimensions met the manufacturers' data; none of the products showed any failure during the test program. Cell sizes in the middle part of the stents ranged from 1.36 mm(2) (Wallstent) to 15.10 mm(2) (Acculink). Bending forces at 20 degrees /30 degrees ranged from 0.063 N / 0.074 N (Cristallo Ideale) to 0.890 N / 0.616 N (Xact); forces to achieve torsion at 10 degrees /15 degrees ranged from 0.032 N / 0.043 N (Acculink) to 0.905 N / 1.071 N (Xact). According to the parallel plate method, mean lowest force was measured for Xact (0.765 N), while the Wallstent had the highest force (2.136 N). Mean radial force measurements were lowest for Cristallo Ideale (9.06 N at mid part) and highest for Protégé (24.09 N). The Cristallo Ideale stent at mid part resisted penetration by all but the smallest plastic spheres (1.5-mm spheres penetrated only at 0.65 N); the Precise and Protégé stent had the highest variation in sphere penetration (1.5- to 4.0-mm spheres). Only the Acculink let 6-mm spheres penetrate. Despite comparable stent sizes, these carotid stents showed differences in behavior due to stent design. The open-cell design displayed the greatest flexibility and adaptability to the vessel but easily allowed particle penetration due to the open structure. Closed-cell designs had low flexibility and thus low adaptability to the vessel but high resistance to particle penetration due to the closed-cell design and high scaffolding. The hybrid stent design (Cristallo Ideale) was able to combine both the flexibility of an open-cell structure and the resistance to particle penetration of closed-cell structures.
    Journal of Endovascular Therapy 05/2009; 16(2):168-77. · 2.70 Impact Factor
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    ABSTRACT: Distal embolization following percutaneous intervention is a universal phenomenon that has been reported in various vascular beds. Distal emboli are also very common during lower extremity percutaneous peripheral interventions. Some data from case reports and registries are currently available. Clinical data have shown that the application of an embolic protection device in the lower limb arteries is safe. Prospective and, ideally, randomized trial data are warranted to justify the increased use of filters in lower extremity interventions, despite the obvious benefits that these devices provide. However, the clinical relevance of distal embolization in the lower extremity remains unquantified.
    Journal of Endovascular Therapy 02/2009; 16 Suppl 1:I163-9. · 2.70 Impact Factor
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    ABSTRACT: To analyze the immediate and midterm success of low-profile stent placement in calcified ulcerated lesions of the infrarenal aorta in patients with arterial occlusive disease. In this prospective case series, 13 symptomatic patients (eight men, five women; mean age, 64.8 years +/- 12.1; age range, 44-84 years) with focal calcified ulcerated stenoses of the infrarenal aorta were treated with stent placement by using a low-profile technique in a radiology intervention center during a 4-year period. Clinical examinations and duplex ultrasonography were used to evaluate the stents? patency and clinical success. Kaplan-Meier graphs were calculated to analyze the freedom-of-symptom rate. The initial technical success rate was 92% (12 of 13 patients). Due to extended calcifications, a residual stenosis of 50%-60% remained in one patient. No peri-interventional complications occurred. The mean follow-up was 26 months (range, 5-53 months). During follow-up, one patient had a restenosis after 7 months and presented clinically with Fontaine stage IIb. Two patients had iliac and/or femoral stenoses, and both presented with Fontaine stage IIb. One patient's symptoms originated from the lumbar spine. Primary patency and primary clinical success rates were 85% and 69%, respectively. According to Kaplan-Meier tables, the freedom-from-symptom rates were 92%, 84%, 73%, and 63% at 0, 7, 12, and 21 months, respectively. Low-profile stent placement in calcified, ulcerated lesions of the infrarenal aorta is an effective and safe treatment for symptomatic stenoses in patients with arterial occlusive disease after a mean follow-up of 26 months.
    Journal of Vascular and Interventional Radiology 03/2008; 19(2 Pt 1):182-8. · 2.00 Impact Factor
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    ABSTRACT: To characterize a new protocol of computed tomographic (CT) fluoroscopy-guided biopsy of the lung and upper abdomen to minimize the intervention time, complication rate, and exposure to ionizing radiation for both the patient and the radiologist. Fifty patients (23 women, 27 men; mean age, 64.3 years; age range, 36-83 years) with lung (n = 41) or upper abdomen (n = 9) nodules 15 mm or smaller underwent CT fluoroscopy-guided biopsy from November 2005 to October 2006. The mean nodule diameter was 12.6 mm (range, 8-15 mm), the mean depth to skin was 57.3 mm (range, 20-114 mm), and the mean depth of nodules from pleura and/or peritoneum was 18.9 mm (range, 1-77 mm). Histopathologic evaluation of samples was performed on the day of the procedure. A CT fluoroscopy-guided biopsy protocol was established as follows: (a) native CT with breath-holding at an intermediate respiration level, (b) selection of section position with target nodule and insertion of an 18-gauge coaxial biopsy needle extrapleurally and/or extraperitoneally virtually targeting at nodule, (c) start of CT fluoroscopy (130 kVp, 30 mAs, 5-mm-thick sections) at inspiration level with the patient expiring, (d) stop of CT fluoroscopy when the target nodule reaches the section position, short breath-hold, needle advancement to the target nodule, (e) control of needle position with CT fluoroscopy, and (f) biopsy. The mean total table time was 23.8 minutes (range, 15-41 minutes), the mean duration of CT fluoroscopy was 8.2 seconds (range, 4-23 seconds), and the mean duration of breath-holding--including needle insertion to target nodule and control CT fluoroscopy--was 10.3 seconds (range, 5-15 seconds). There were three minor pneumothoraces that required no further intervention, seven minor pulmonary hemorrhages, three moderate pulmonary hemorrhages with hemoptysis, and one moderate liver hematoma. There were no major complications. The diagnostic accuracy of biopsy samples was 96%. The presented modification of CT fluoroscopy-guided biopsy of mobile pulmonary and upper abdominal lesions is a rapid and safe procedure, requiring only short exposure to ionizing radiation.
    Journal of Vascular and Interventional Radiology 11/2007; 18(10):1241-8. · 2.00 Impact Factor
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    ABSTRACT: The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committe was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30 degrees , field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses > or = 50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies.
    CardioVascular and Interventional Radiology 06/2007; 30(3):376-82. · 2.14 Impact Factor
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    ABSTRACT: Prospective evaluation of diagnostic accuracy of single field-of-view contrast-enhanced MR Angiography (ceMRA) with 1.0M gadobutrol compared to intraarterial DSA in body arteries. In an European multicenter study 179 patients underwent ceMRA and DSA. For each indication five prospectively defined vessel segments were evaluated by local investigators onsite and by three site-independent blinded readers (BR) independently. The agreement between ceMRA and DSA diagnosis was statistically significant in the onsite (96.6%) and blinded reader (86.6-90.2%) evaluation. Sensitivity, specificity, accuracy, positive (PPV) and negative predictive values (NPV) for detection of relevant stenosis (>50%) were calculated for the right and left internal carotid arteries, and common and external iliac arteries: Sensitivity was 95-98% (onsite) and 76-96% (BR), specificity 94-96% (onsite) and 86-94% (BR), accuracy 96% (onsite) and 87-93% (BR), NPV 98-99% (onsite) and 84-98% (BR), and PPV 79-93% (onsite) and 44-91% (BR), respectively. CeMRA of body arteries using 1.0M gadobutrol provides diagnostic information comparable to intraarterial DSA.
    European Journal of Radiology 02/2007; 61(2):315-23. · 2.51 Impact Factor
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    ABSTRACT: To determine mid-term patency rates after endovascular treatment of supraaortic atherosclerotic arterial stenoses and occlusions using percutaneous transluminal angioplasty (PTA) and stent placement. During a period of 83 months, 48 patients (18 female, 30 male; mean age 61 years, range 31-82 years) were included into this prospective single-center study. Fifty-five lesions of the brachial and cephalic arteries (subclavian/axillary artery n = 42, innominate artery n = 7, origin common carotid artery n = 6) were treated using PTA (n = 38), PTA plus stent (n = 11) or primary stent placement (n = 6). For anticoagulation, patients received a bolus of heparin (5000 IU) intraarterially during the intervention followed by intravenous application for 24h. At discharge, life-time application of ASA (100mg/day) was initiated. Follow-up protocol included clinical examination, colour-coded duplex ultrasound and intraarterial angiography in case of re-stenosis. PTA and stent placement were technically successful in all patients (100%). No major complications occurred. Of seven patients presenting with total occlusions, six were treated with stent placement. Stent implantation was also performed in all lesions located at the origin of the supraaortic arteries (n = 6). In 38 lesions, the result of PTA was satisfactory. Mean follow-up time is 22 months (range 1-83 months). During follow-up examinations, re-stenoses occurred in 10 cases (at 1 month n = 2, at 6 months n = 2, at 12 months n = 3, at 24 months n = 3). In 9 lesions, re-interventions were performed (PTA n = 7; PTA plus stent n = 2). According to Kaplan-Meier life-table analysis, cumulative primary and primary assisted patency rates are 69.5% (patients at risk n = 15; standard error 9%) and 90.6% (patients at risk n = 16; standard error 6.3%) at 20 months, respectively. Endovascular treatment of atherosclerotic obstructive disease in brachial and cephalic arteries is a safe procedure showing promising mid-term patency rates.
    Rontgenpraxis 01/2007; 56(4):119-28.
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    ABSTRACT: ObjectiveTo determine mid-term patency rates after endovascular treatment of supraaortic atherosclerotic arterial stenoses and occlusions using percutaneous transluminal angioplasty (PTA) and stent placement.Patients and MethodsDuring a period of 83 months, 48 patients (18 female, 30 male; mean age 61 years, range 31–82 years) were included into this prospective single-center study. Fifty-five lesions of the brachial and cephalic arteries (subclavian/axillary artery n=42, innominate artery n=7, origin common carotid artery n=6) were treated using PTA (n=38), PTA plus stent (n=11) or primary stent placement (n=6). For anticoagulation, patients received a bolus of heparin (5000 IU) intraarterially during the intervention followed by intravenous application for 24 h. At discharge, life-time application of ASA (100 mg/day) was initiated. Follow-up protocol included clinical examination, colour-coded duplex ultrasound and intraarterial angiography in case of re-stenosis.ResultsPTA and stent placement were technically successful in all patients (100%). No major complications occurred. Of seven patients presenting with total occlusions, six were treated with stent placement. Stent implantation was also performed in all lesions located at the origin of the supraaortic arteries (n=6). In 38 lesions, the result of PTA was satisfactory. Mean follow-up time is 22 months (range 1–83 months). During follow-up examinations, re-stenoses occurred in 10 cases (at 1 month n=2, at 6 months n=2, at 12 months n=3, at 24 months n=3). In 9 lesions, re-interventions were performed (PTA n=7; PTA plus stent n=2). According to Kaplan–Meier life-table analysis, cumulative primary and primary assisted patency rates are 69.5% (patients at risk n=15; standard error 9%) and 90.6% (patients at risk n=16; standard error 6.3%) at 20 months, respectively.ConclusionsEndovascular treatment of atherosclerotic obstructive disease in brachial and cephalic arteries is a safe procedure showing promising mid-term patency rates.
    Rontgenpraxis. 01/2007;
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    ABSTRACT: This article focuses on stent placement in mesenteric arteries in patients with the rare diagnosis of chronic mesenteric ischemia. We present a survey from the initial stage of recognition of this gastrointestinal disorder and its manifestations to treatment by stenting to avoid further ischemic episodes and bowel infarction and necrosis. The advantages of stent placement in splanchnic arteries are discussed in comparison to open surgical revascularization.
    Abdominal Imaging 01/2007; 32(3):304-9. · 1.91 Impact Factor
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    ABSTRACT: The objective of the study was to evaluate MRI for visualization of acromioclavicular (ac) joint structures in cadaveric shoulders, asymptomatic volunteers and symptomatic patients with trauma of the ac-joint. Three cadaveric shoulders were examined to find adequate planes and sequences for MRI. Afterwards, MR images were correlated to corresponding anatomical sections. Six asymptomatic volunteers and 13 patients were scanned in a 1.5 T Magnetom Vision with three sequences in the following planes: (1) parallel to the clavicle; (2) orthogonal to the ac joint, each time a fat-suppressed proton density-weighted + T2-sequence (TR/TE 4,000/15 ms) was performed; (3) parallel to the clavicle, T1-SE (TR/TE 817/20 ms). The parameters were: slice thickness 3 mm, field-of-view 180 mm, matrix 210x256 pixels. Standard of reference in the patients was clinical examination and conventional X-rays. Classification was by Rockwood grades I-VI. MRI allowed excellent visualization and diagnoses of ac-joint structures in volunteers and patients (n=6 normal, n=1 Rockwood I, n=5 Rockwood II, n=3 Rockwood III, n=4 Rockwood V). On MRI, in one lesion type II and III each, a lower lesion type was suspected clinically and by X-ray. In one patient additional information by MRI led to surgery. MRI allows excellent anatomical display of ac-joint structures and can give clinically relevant information on type and extension of ac-joint trauma, which may influence therapy.
    European Radiology 08/2006; 16(7):1488-93. · 4.34 Impact Factor
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    ABSTRACT: To evaluate fat-suppressed (FS) proton-density-weighted (PDw) turbo spin-echo (TSE) magnetic resonance imaging for the detection of anterior and posterior cruciate ligament lesions in comparison to arthroscopy. In a prospective study 31 knee joints were imaged on a 1.5T MR scanner (Vision, Siemens, Erlangen) prior to arthroscopy using following sequences: (a) sagittal FS-PDw/T2w TSE (TR/TE: 4009/15/105 ms); (b) sagittal PDw/T2w TSE (TR/TE:3800/15/105 ms). Further imaging parameters: slice thickness 3mm, FOV 160 mm, matrix 256 x 256. A total of 62 anterior and posterior cruciate ligaments (ACL/PCL) were evaluated, standard of reference was arthroscopy. Sensitivity, specificity, positive (ppv) and negative predictive value (npv) and accuracy were calculated. Twenty-one cruciate ligament ruptures were detected in arthroscopy, 19 ACL- and 2 PCL-ruptures (on MRI 34/124, 25/62 ACL, 9/62 PCL lesions). For all four sequences in the 31 patients with arthroscopic correlation sensitivity, specificity, ppv, npv and accuracy were 86%, 98%, 95%, 93% and 94% for detection of tears, and 84%, 100%, 100%, 80% and 90% for ACL-ruptures respectively. The two PCL-ruptures were true positive in all sequences, one intact PCL was diagnosed as torn (false positive). Fat-suppressed PDw/T2w TSE-MR sequences are comparable to PDw TSE sequences for the detection of ACL/PCL-lesions.
    European Journal of Radiology 07/2006; 58(3):411-5. · 2.51 Impact Factor
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    ABSTRACT: To analyze the immediate and midterm success of stenting of mesenteric arteries by a monorail technique in patients with chronic mesenteric ischemia. In this prospective case series, 19 patients (11 male, 8 female; mean age, 62.9 +/- 10.4 y; range, 36-82 y) with 23 symptomatic stenoses of mesenteric arteries were treated with stent placement by a monorail technique in a radiologic intervention center over a period of 4.5 years. Clinical examinations and duplex sonography were used to evaluate the stents' patency and clinical success. Kaplan-Meier graphs were calculated to analyze the patency and freedom-from-symptom rate. Initial technical success rate was 22/23 (96%). Mean follow-up was 17 months (range, 1-58 mo). Primary patency and primary clinical success rates were 82% and 78%, respectively. According to Kaplan-Meier tables, the patency rates were 96%, 87%, 76%, and 61% at 0, 1, 15, and 24 months, respectively, and the freedom-from-symptom rates were 95%, 90%, 72%, and 54% at 0, 1, 24, and 30 months, respectively. No peri-interventional complications occurred. Two patients died of cardiac failure in the hospital within 30 days after intervention; deaths were not related to the intervention. Stent placement by a monorail technique in mesenteric arteries is an effective and safe treatment for symptomatic stenoses in patients with chronic mesenteric ischemia after a mean follow-up of 17 months.
    Journal of Vascular and Interventional Radiology 05/2006; 17(4):637-43. · 2.00 Impact Factor