Percutaneous Vascular Closure System Based on an Extravascular, Bioabsorbable Polyglycolic Plug (ExoSeal): Results from 1000 Patients.

PURPOSE: The objective of this prospective study was to evaluate the effectiveness and safety of a percutaneous closure system based on a polyglycolic acid plug for achieving hemostasis. MATERIAL AND METHODS: In this study from 2011 to 2014, a percutaneous vascular closure system (ExoSeal) was used in 1000 patients (mean age 70.6 ± 10.2 years), using antegrade and retrograde techniques within the context of an angiographic intervention. The system was used in conjunction with transfemoral approaches with a sheath size of 6F. Post the intervention (on the following day and after 6 weeks), follow-up was conducted clinically and using color-coded duplex ultrasound. RESULTS: Immediate hemostasis was achieved in 939/1000 patients (93.9%). In the remaining 61 cases, a correct positioning of the polyglycolic acid plug was not possible because of malfunctioning of the device, massive vascular wall calcifications, postoperative scar tissue, or too steep a puncture angle. In these cases, manual compression was successful. There was one retroperitoneal bleeding requiring transfusion. Minor complications were observed (7.4% in total) with 10 pseudoaneurysm (1%), 63 inguinal hematomas (up to 3 cm; 6.3%), and 1 stenosis (0.1%). CONCLUSION: Safe and effective hemostasis is possible with the percutaneous ExoSeal closure system at puncture sizes of 6F.

Value of fat-suppressed proton-density-weighted turbo spin-echo sequences in detecting meniscal lesions: comparison with arthroscopy.

PURPOSE: To evaluate fat-suppressed (FS) proton-density-weighted (PDw) turbo spin-echo (TSE) magnetic resonance imaging (MRI) compared to arthroscopy in the detection of meniscal lesions. MATERIAL AND METHODS: In a prospective study, 31 knee joints were imaged on a 1.5T MR scanner before arthroscopy using the following sequences: (a) coronal and sagittal FS-PDw TSE (TR/TE: 4009/15 ms); (b) coronal T1w SE (TR/TE: 722/20 ms), and sagittal PDw TSE (TR/TE: 3800/15 ms). Other imaging parameters were: slice thickness 3 mm, FOV 160 mm, matrix 256 x 256. A total of 186 meniscal regions (62 menisci; anterior horn, body, posterior horn) were evaluated. Standard of reference was arthroscopy. Sensitivity, specificity, negative predictive value (npv), positive predictive value (ppv), and accuracy were calculated. RESULTS: Arthroscopically, meniscal lesions were detected in 55/186 segments (35 medial and 20 lateral meniscal lesions). Sensitivity, specificity, npv, ppv, and accuracy for combination of coronal and sagittal FS PDw TSE were 91.4%, 98.3%, 95%, 97%, and 93.5% for the medial meniscus, and 90%, 98.6%, 97.3%, 94.7%, and 96.8% for the lateral. The results were comparable to the combination of coronal T1w SE and sagittal PDw TSE for the medial (88.6%, 98.3%, 93.4%, 96.9%, 91.4%) and the lateral (90%, 95.9%, 97.2%, 85.7%, 92.5%) meniscus. CONCLUSION: FS PDw TSE-MR sequences are an excellent alternative for the detection of meniscal lesions in comparison with diagnostic arthroscopy.

Comparable ultrasound measurements of ten anatomical specimens of infant hip joints by the methods of Graf and Terjesen.

PURPOSE: To define which sonographic section planes relative to the acetabular inlet plane will produce analyzable images with the methods of Graf and Terjesen. MATERIAL AND METHODS: Anatomical specimens of infant hip joints were investigated in a water bath using the methods of Graf and Terjesen. Acetabular position was varied in defined increments with respect to the ultrasound beam. The alpha angles and the femoral head coverage (FHC) were measured. RESULTS: To obtain images analyzable by the two methods, the ultrasound beam had to intersect with the acetabular inlet plane at defined angles. The acetabular notch had to be anteriorly rotated from the ultrasound beam plane by at least 20 degrees. Beam entry within a 50 degrees sector posterior to the perpendicular on the inlet plane resulted in analyzable images. The stepwise multiple linear regression analysis showed that alpha angles and FHC were much affected by the coronal-plane transducer tilt. CONCLUSION: The fact that caudal tilts of the transducer are associated with reduced alpha angles and FHC values should be kept in mind in clinical ultrasound investigations. It is recommended that the transducer should be put on the greater trochanter perpendicular to the transverse axis of the body.

[First clinical results in a study of contrast enhanced magnetic resonance angiography with the 1.0 molar gadobutrol in peripheral arterial occlusive disease--comparison to intraarterial DSA]. / Erste klinische Erfahrungen zur Wertigkeit der kontrastverstärkten Magnetresonanzangiographie der Becken-Bein-Strombahn mit dem 1,0 molaren Gadobutrol--Vergleich zur i. a. DSA.

PURPOSE: To assess the value of contrast enhanced (CE)-MR angiography (MRA) with 1.0 molar Gadobutrol (Schering, Germany) in comparison to intraarterial DSA in peripheral arterial occlusive disease (PAOD). MATERIALS AND METHODS: Within 48 hours, 30 symptomatic patients with PAOD were examined by CE-MRA (Gadobutrol dose 0.2-0.3 mmol/kg body weight) and DSA. For CE-MRA, a 1.5 T magnet (Vision, Siemens, Germany) was used (FA 35 degrees, TR/TE 4.6/1.8 ms, FOV 400 mm, matrix 230 x 512, total acquisition time 81 sec). Two radiologists evaluated a total of 600 vessel segments for stenotic lesions and image quality (1 = not visible to 5 = excellent). Treatment was independently planned on the basis of the MRA and DSA findings. RESULTS: The Kendall's tau-b coefficient was 0.92 for overall stenotic grading, and 0.92, 0.93 and 0.92, respectively, for the vascular flow in the iliac, femoropopliteal and crural arteries. Sensitivity, specificity, negative and positive predictive value, and accuracy were, respectively, 94, 97, 98 and 92, 96 % for > 50 % stenoses, 95, 99, 99, 95 and 99 % for iliac arteries, 96, 98, 98%, 94 and 97 % for femoropopliteal arteries, and 92, 94, 96, 89 and 94 % for crural arteries. Therapy planning by MRA and DSA coincided in 51 of 54 cases. No relevant adverse event occurred. CONCLUSION: CE-MRA with 1.0 molar Gadobutrol is highly efficient in diagnosing peripheral arterial occlusive disease and correlates excellently with DSA.

Bolus-chasing contrast-enhanced 3D MRA of the lower extremity. Comparison with intraarterial DSA.

PURPOSE: To evaluate step-table 3D contrast-enhanced (CE) MRA with bolus chasing for the detection and grading of stenoses in patients with peripheral vascular disease (PVD) of the lower extremities. MATERIAL AND METHODS: Fifty patients were studied by step-table bolus-chasing 3D-CE-MRA and i.a. DSA within 24 h. After determination of the individual circulation time, CE-MRA was performed during power injection of 40 ml of Gd-DTPA. To cover the whole range between the renal arteries and the feet with three slab locations, the scanner table was manually advanced twice for 350 mm. Total imaging time was 1 min 23 s. The degree of stenosis and image quality of the images were evaluated by 2 observers. In addition, a treatment plan was established based on the 3D-CE-MRA and DSA investigations. RESULTS: In 44 of 50 patients (88%), the visualization of the arterial tree from the renal arteries to the foot was possible. Forty-six of 50 patients (92%) had good or very good image quality. In the calf, 3D-CE-MRA was superior to DSA in 6 patients. For the detection of stenosis >50%, sensitivity was 99.5%, specificity 98.8%, positive predictive value 95.6% and the negative predictive value 99.8%. Cohen's kappa for 3D-CE-MRA vs. DSA was 0.926; for interobserver agreement it was 0.96. CONCLUSION: Bolus-chasing 3D-CE-MRA with manual table movement is a simple, robust and easy to perform technique which provides high quality angiograms of the lower extremity arterial system and is comparable to, i.a., DSA for the diagnosis of PVD.

Selective water excitation for faster MR imaging of articular cartilage defects: initial clinical results.

Our objective was to compare a water-excitation (WE) 3D fast low-angle shot (FLASH) MR sequence for faster imaging of articular cartilage defects of the knee to a conventional fat-saturated (FS) 3D FLASH MR sequence. This prospective study included 16 knees of 16 patients with suspected cartilage lesions. The MR imaging in transverse and sagittal planes included (a) FS 3D FLASH (TR/TE: 45 ms/11 ms, scan time 8 min, flip angle 50 degrees), and (b) WE 3D FLASH (TR/TE: 28 ms/11 ms, scan time 4 min 58 s, flip angle 40 degrees). For each sequence signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were quantified. The detected cartilage lesions were evaluated using a semi-quantitative four-scale scoring system (grades 0-III). The data were compared between the sequences using the paired Student's t-test. No statistically significant differences between the sequences were found for SNR, CNR, and cartilage defect grading (p=0.14-0.8). The WE 3D FLASH MR imaging seems to be promising for fast imaging of articular cartilage lesions of the knee.

Percutaneous management of occlusive arterial disease associated with vasculitis: a single center experience.

The purpose of this study was to evaluate the safety and effectiveness of percutaneous transluminal angioplasty for occlusive arterial disease associated with vasculitis. Eleven patients (10 women, 1 man; ages 35-82 years) with the diagnosis of vasculitis of the large vessels underwent interventional treatment during intraarterial angiography. The causes included giant cell arteritis (n = 8) and Takayasu arteritis (n = 3). Thirty-three occlusive lesions (including brachiocephalic and renal arteries, and arteries of upper and lower extremities) were treated with balloon angioplasty and/or stent placement. Follow-up included clinical examination, angiography, and color duplex ultrasound. Technical success was 100% (25/25) for stenoses and 50% (4/8) for occlusive lesions, representing all lesions combined from different anatomic locations. Dissection (n = 3) and arterial rupture with retroperitoneal hematoma (n = 1) was found in three patients. During follow-up (mean 12 months), restenoses (n = 8) and re-restenoses (n = 1) occurred in 8 vascular areas. Three of these lesions were treated with repeated PTA (n = 4). The cumulative primary clinical success rate was 67.6%, cumulative secondary success rate 74.4%, and cumulative tertiary success rate 75.9%. Interventional therapy in systemic vasculitis provides promising results in technical success rates and followup. Angioplasty may result in arterial injury, but the rate of complications is low.

Influence of the pulmonary annulus diameter on pulmonary regurgitation and right ventricular pressure load after repair of tetralogy of Fallot.

OBJECTIVE: To assess the influence of the pulmonary annulus diameter after reconstruction of the right ventricular (RV) outflow tract at repair of tetralogy of Fallot on pulmonary regurgitation and RV pressure load; and to evaluate the impact of pulmonary regurgitation on RV size and function. SETTING: Paediatric cardiology and diagnostic radiology departments of a tertiary referral centre. PATIENTS: 67 patients were examined at a median of 4.8 years after repair of tetralogy of Fallot by means of biplane angiocardiography and magnetic resonance imaging (MRI). MAIN OUTCOME MEASURES: Pulmonary annulus diameter and area, pulmonary regurgitant fraction, RV to left ventricular (LV) systolic pressure ratio, RV end diastolic volume, and RV ejection fraction were assessed. RESULTS: There was a significant positive correlation between pulmonary annulus area indexed to body surface area and pulmonary regurgitation (angiocardiography: r = 0.55, p < 0.001; MRI: r = 0.59, p < 0.001). No significant correlation was found between pulmonary annulus index and RV to LV systolic pressure ratio even in patients with small pulmonary annulus areas (r = -0.24, NS). Pulmonary regurgitant fraction was positively correlated with normalised RV end diastolic volume (angiocardiography: r = 0.42, p < 0.05; MRI: r = 0.56, p < 0.01). RV ejection fraction decreased with increasing pulmonary regurgitation (angiocardiography: r = -0.42, p < 0.05; MRI: r = -0.41, p < 0.05). CONCLUSIONS: The extent of pulmonary regurgitation after tetralogy of Fallot repair correlates with the postoperative size of the pulmonary annulus and is closely correlated with the enlargement of the RV. An enlargement of the pulmonary annulus to the second lower standard deviation of normal results in a decrease of pulmonary regurgitation and is sufficient to achieve adequate RV pressure unloading.

[Sport injuries of the extensor mechanism of the knee]. / Sportverletzungen des Kniestreckapparates.

Injuries of the extensor mechanism of the knee occur frequently during sport activity. For a successful treatment they must be diagnosed early. Besides osseous structures the patellar tendon, the patella, the quadriceps muscle and tendon, retinacula and bursae can be affected. After initial clinical examination there are different noninvasive imaging modalities available for assessment of bone, cartilage, ligaments, tendons and soft tissue. Conventional radiographs are still the basic imaging tool for the clinician. Additional information about the osseous status is provided by computed tomography, whereas sonography plays an important role concerning diagnosis of soft tissue injuries. For the detection of cartilagenous, ligamentous or tendon lesions MRI is the superior non-invasive imaging modality.

Gadobutrol: an alternative contrast agent for digital subtraction dacryocystography.

We report the application of gadobutrol as a contrast medium for digital subtraction dacryocystography (DS-DCG) in patients with known allergy to iodinated contrast agent. Gadobutrol has the double gadolinium concentration (1.0 mmol/ml) of other gadolinium-based contrast agents. Quality of the DS-DCG images obtained with gadobutrol was comparable to DS-DCG images obtained with iodinated contrast medium. Radiodensity measurements using a micro-CT scanner confirmed a high radiodensity of gadobutrol which was comparable to the radiodensity of iopentol with a iodine concentration of 250 mg/ml and only approximately 20% lower than the radiodensity of iopentol with a concentration of 300 mg/l. Gadobutrol is a well-suited substitute for DS-DCG in patients with allergy to iodinated contrast agents.

Acetabular inclination and anteversion in infants using 3D MR imaging.

PURPOSE: To establish if 3D MR imaging could be used for measurements of acetabular inclination and anteversion in infants specimens. MATERIAL AND METHODS: 3D MR data of 3 pelvic preparations of 6-week- to 10-month-old infant specimens was gathered. MR imaging in transaxial and frontal planes was carried out to measure the acetabular inclination and anteversion: a method to determine the MR planes for measurements is described. It was oriented on anatomical landmarks of the pelvis and therefore allowed adjustment of the frontal and transaxial planes, independent of the pelvis position. RESULTS: The mean acetabular inclination angle was 48 degrees, and the mean acetabular anteversion was 23 degrees. Because of the low number of cases the results can only be assessed as a tendency, but MR imaging seems to be suitable for measurements of acetabular inclination and anteversion.

MR imaging of the neural foramina of the cervical spine. Comparison of 3D-DESS and 3D-FISP sequences.

PURPOSE: To assess whether a single three-dimensional double-echo steady state (3D-DESS) sequence can produce equivalent results when compared to a 3D free induction with steady precession (3D-FISP) sequence for the evaluation of the neural foraminal diameter and structures. MATERIAL AND METHODS: Five phantoms were imaged on CT with 3-mm axial slices followed by reformatted axial 3D-DESS and 3D-FISP sequences. In addition, 3D-DESS and 3D-FISP sequences of 20 healthy subjects were compared with regard to image quality, differentiation between vertebrae and discs, differentiation between discs and neural foramina, and differentiation between vertebrae and neural foramina. RESULTS: Compared with CT, 3D-DESS and 3D-FISP sequences consistently underestimated the diameters of the neural foramina. The mean difference values for the 3D-DESS was 12.8%, compared to 9.5% for the 3D-FISP sequence. Concerning the in vivo studies, the 3D-DESS sequence was superior but not statistical significant to the 3D-FISP sequence with regard to image quality, differentiation between vertebrae and discs, differentiation between discs and neural formina, and identification of the nerve roots. CONCLUSION: The 3D-DESS sequence is moderately accurate in the evaluation of the neural foraminal size. Compared to the 3D-FISP sequence, the 3D-DESS sequence is compatible concerning the image quality, differentiation between the cervical vertebrae and discs, and between the discs and neural foramina.

[Alar ligaments: radiological aspects in the diagnosis of patients with whiplash injuries]. / Stellenwert bildgebender Verfahren in der Diagnostik der Ligg. alaria nach Beschleunigungsverletzung der Halswirbelsäule.

Post-traumatic changes of the alar ligaments have been proposed to be the cause of chronic pain in patients after whiplash injury of the cervical spine. In addition to an asymmetric dens position, widening of the atlantodental distance to more than 12 mm can be an indirect sign of an alar ligament rupture. CT is recommended for detection of a avulsion fracture of the occipital condyle. Isolated ruptures of the alar ligaments are best visualized on MRI. In patients with chronic impairments after whiplash injuries changes of the alar ligaments on MRI must be differentiated from normal variants in healthy individuals.

[Early results with a monorail-stent-balloon device for endovascular treatment of renal artery stenosis]. / Erste Erfahrungen mit einem Monorail-Stent-Ballon-System zur endovaskulären Behandlung von Nierenarterienstenosen.

OBJECTIVE: To evaluate the technical feasibility of a new monorail-stent-balloon device for treatment of renal artery stenosis (RAS). PATIENTS AND METHODS: During a study period of 18 months, 38 patients with proven RAS in 41 cases (hypertension n = 36, renal insufficiency n = 13) and indication for stenting (calicified ostial lesions n = 35, insufficient PTA n = 4, dissection n = 2) were enrolled into this prospective evaluation. Pre-mounted stents (Rx-Herculink(TM) 5 mm = 13, 6 mm = 34, 7 mm = 1) were implanted a transfemoral (n = 35) or transbrachial approach (n = 6). Mean grade and lengths of stenosis measured were 88 % plus minus 10 and 9 mm plus minus 5. RESULTS: Renal stent implantation was technically successful in all cases (100 %). In 7 cases a second stent had to be implanted to cover the entire lesion. The transstenotic pressure drop decreased from 88 mmHg plus minus 10 before to 1 mmHg plus minus 1.8 after the procedure. Remaining stenosis measured 0.7 % plus minus 4.2. Serum creatine levels decreased from 1.9 mm/dl to 1.5 mg/dl (n. s.), blood pressure decreased from 178/94 mmHg to 148/79 mmHg (p < 0.0001) after the intervention. Primary and secondary patency rates at 6 months were 72 % (Standard Error 9.8 %) and 77 (% (Standard Error 9.2 %), respectively. CONCLUSION: With the used monorail-stend-balloon device a technically easy, secure and exact renal stent placement is guaranteed, patency rates are similar to those described in the current literature.

Uncommon presentation of a giant biliary cystadenoma: correlation between MRI and pathologic findings.

An uncommon case of a giant mucinous biliary cystadenoma (BCA) of the liver is described. On T2-weighted and STIR images, a large hyperintense cystic mass revealed some septations and multiple intracystic masses of similar size and shape and uniform signal intensity, which was isointense to liver parenchyma. On T1-weighted images, intracystic bodies were obscured and the cyst was hyperintense. The magnetic resonance (MR) appearance of intracystic fluid and structures was not due to mucinous or proteinous or hyperproteinous material, but corresponded to clots floating within hemorrhagic fluid.

Assessment of the position of the distal portion of the ulna in lateral projection radiographs of the wrist: analysis of the influence of pronation-supination and flexion-extension on the pisoscaphoid and the ulnotriquetral distances: a cadaver study.

RATIONALE AND OBJECTIVES: Accurate assessment of the distal radioulnar joint is of paramount importance for the detection of possible dislocation or subluxation. Using a cadaveric model, the authors attempted to establish a quantitative method that would allow identification of normal and abnormal distal radioulnar joint anatomy on well-positioned and rotated conventional radiographs. METHODS: Four cadaveric wrists, in which subsequent sectioning confirmed the absence of disease, and one cadaveric wrist with a circumscribed lesion of the triangular fibrocartilaginous complex were studied. Defined movements in flexion and extension (+/- 10 degrees, 20 degrees, 30 degrees ) and in pronation and supination (+/- 10 degrees, 20 degrees, 30 degrees ) as well as combined flexion/extension and pronation/supination were performed. The ulnotriquetral and the pisoscaphoid distances were assessed in each position. Correlation with cryosections was achieved. RESULTS: A strong linear correlation between the degree of pronation or supination and the pisoscaphoid and ulnotriquetral distances was noted. Flexion and extension produced no significant effect on the pisoscaphoid distance, but a defined shift of the ulnotriquetral distance occurred with increasing flexion and extension. CONCLUSIONS: If all parameters are taken into account, this correlation aids in estimating the degree of possible malpositioning of the wrist during radiography and the degree of subluxation of the distal radioulnar joint. Tabular data with parameters to correct for instances of malrotated images and to estimate the extent of dislocation or malrotation of the distal radioulnar joint are provided.

Magnetic resonance arthrography of the acetabular labrum: value of radial reconstructions.

The intention was to compare the sensitivity and specificity of radial planes with oblique coronal and oblique axial planes for the detection of labral abnormalities of the acetabulum on magnetic resonance arthrography (MRa). Twenty cadaveric hip joints were examined by radiography and MRa. For MRa, 15 ml of a solution of iodinated contrast material and gadolinium diethylene triamine tetra-acetic acid (Gd-DTPA; 100:1) were injected under fluoroscopic guidance. MRI was performed on a 1.5-T MR scanner with a fat-suppressed 3D-FLASH sequence (TR/TE/flip-angle 42 ms/10 ms/40 degrees; field of view 16 cm, matrix 256 x 256, section thickness 1.5 mm, pixel size 0.7 x 0.7 mm). Multiplanar image reconstructions were done perpendicular to the acetabulum in oblique coronal and oblique axial planes and in radial planes. Macroscopic and histopathologic examination of the labral specimens was performed. Labral lesions were found in 15/20 hips (75%) on pathologic examination. Six hips demonstrated labral degeneration. The labrum was partially detached in 7 hips and completely detached in 2 hips. A flap-like labrum was found in 2 cases, 1 with partial detachment of the labrum and 1 with a degenerated labrum. Using oblique coronal and oblique axial reconstructions, pathologic findings were confirmed by MRa in 9/15 specimens (sensitivity 60%). There were no false-positive findings (specificity 100%, accuracy 70%). Also, 3/6 labral degenerations without detachment, 4/7 partial detachments, and 2/2 complete detachments were correctly diagnosed. Two flap-like labra were not recognized. With radial reconstructions, pathologic findings were correctly confirmed in 12/15 specimens (sensitivity 80%) without false-positive findings (specificity 100%, accuracy 85%). Also, 3/6 labral degenerations without detachment, 6/7 partial detachments, 2/2 complete detachments, and 1/2 flap-like labra were correctly diagnosed. MRa of the acetabular labrum using radial reconstructions is well suited to delineate the acetabular labrum and to diagnose labral detachments. Radial reconstructions allow for perpendicular display of the whole acetabular circumference and are more accurate for the diagnosis of acetabular labral lesions, when compared with oblique coronal and oblique axial reconstructions.

Randomized study to compare PTA alone versus PTA with Palmaz stent placement for femoropopliteal lesions.

PURPOSE: The purpose of this study was to evaluate whether percutaneous transluminal angioplasty (PTA) combined with Palmaz stent placement provides long-term advantages compared to PTA alone after 34 months of follow-up in the femoropopliteal region. MATERIALS AND METHODS: Thirty patients randomized to undergo PTA in combination with stent placement and 23 patients randomized to undergo PTA alone were evaluated. RESULTS: Mean follow-up (+/-SD) for the PTA group was 33.8 months (+/- 8.7) and for the Palmaz group 29.1 months (+/- 6.2), with a maximum follow-up period of 39 months for both groups. No significant differences in primary or secondary patency rates could be observed at 12 or 39 months. After 39 months, the primary patency rate for PTA alone was 68.4% and the secondary patency rate was 89.5%; the primary patency rate for PTA with stent placement was 62% and the secondary patency rate was 90%. CONCLUSIONS: The results of this study show that even after a long-term follow up of more than 3 years, PTA with stent placement in the femoropopliteal artery does not produce better results than PTA alone, although it does provide better initial luminal gain after the procedure.

Mechanical thrombectomy of major and massive pulmonary embolism with use of the Amplatz thrombectomy device.

RATIONALE AND OBJECTIVES: To evaluate the feasibility of mechanical thrombectomy with the Amplatz thrombectomy device (ATD) in restoring patency of acutely thrombosed pulmonary arteries resulting from pulmonary embolism for the improvement of patient outcome. METHODS: Mechanical thrombectomy with the ATD (8F) was performed in nine consecutive patients with angiographically documented thrombus in the left or right pulmonary artery resulting from deep vein thrombosis (n = 4) or unknown cause (n = 5). RESULTS: The Miller index decreased from 18 to 11. In all patients, the majority of the thrombus in the pulmonary artery was cleared after a mean activation time of the ATD of 367 seconds. Thrombectomy was performed with the ATD alone (n = 4) or with additional long-term fibrinolysis therapy (n = 5) with infusion of recombinant tissue-type plasminogen activator. Pulmonary arterial pressure decreased from a mean of 57 mm Hg before mechanical thrombectomy to 55 mm Hg directly after the procedure and to 39 mm Hg after termination of the recombinant tissue-type plasminogen activator infusion. CONCLUSIONS: Mechanical thrombectomy with the ATD in patients with minor and major pulmonary embolism is technically feasible and safe. It is a potential alternative to drug-mediated thrombolysis and surgery. However, the incremental benefit of the ATD over conventional treatments could be shown only in a randomized controlled study.

[MR imaging of the articular cartilage]. / Gelenkknorpel in der MR-Tomographie.

MR imaging has evolved to the best non-invasive method for the evaluation of articular cartilage. MR imaging helps to understand the structure and physiology of cartilage, and to diagnose cartilage lesions. Numerous studies have shown high accuracy and reliability concerning detection of cartilage lesions and early changes in both structure and biochemistry. High contrast-to-noise ratio and high spatial resolution are essential for analysis of articular cartilage. Fat-suppressed 3D-T1 weighted gradient echo and T2-weighted fast spin echo sequences with or without fat suppression are recommended for clinical routine. In this article the anatomy and pathology of hyaline articular cartilage and the complex imaging characteristics of hyaline cartilage will be discussed.