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[en] We describe a cheap and efficient method for filling the vascular space of ex vivo tissue samples with a radiopaque material that can be used in computed tomography imaging. The filling material consists of curd, water, and a radiological contrast agent. Viscosity ranges and the degree of attenuation of X-rays of the filling material can be easily adjusted to the requirements of a specific application. The method is non-destructive and without negative effects on subsequent histological examinations.

[en] Over the last few years, cross-sectional imaging became clinically accepted for qualitative and quantitative analysis of left ventricular (LV) function. The results have an impact on diagnosis, therapy and follow-up, and some parameters even proved to be independent predictors of mortality. Besides well established cardiologic techniques, such as ventriculography and echocardiography, more recent radiologic techniques, especially magnetic resonance imaging (MRI) and multislice spiral computed tomography (MSCT), became accepted for imaging of LV function. Assessment of LV function with cardiac MRI is based on cine sequences. Over the last years, parallel imaging techniques, fast imaging with steady state free precession and real time sequences were successfully introduced. Further improvements were achieved by stress examinations and MR-tagging. Cardiac MSCT with retrospective ECG-dating allows for reliable determination of LV volumes. Assessment of wall motion is feasible but limited to some degree. Nevertheless, cardiac MSCT is a powerful alternative for patients with contraindications to MRI. Aim of this article is to review theoretical and technical aspects, opportunities and limitations of MRI and MSCT for functional imaging of the heart. (orig.)

[en] Liposarcoma accounts for approximately 14 % of all malignant soft-tissue tumors, regardless of anatomical location (Kransdorf MJ et al. Imaging of soft tissue tumors. Philadelphia: Lippincott Williams and Wilkins, 2014). Primary mediastinal liposarcomas are rare. Liposarcoma is classified into four histologic subtypes: Myxoid/round cell, pleomorphic, atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma. Dedifferentiated liposarcoma occurs most commonly in the retroperitoneum and in the soft tissues of the extremities. Like atypical lipomatous tumor/well-differentiated liposarcoma, it is characterized by amplification of MDM2 and CDK4 genes on chromosome 12 (Crago AM et al. Curr Opin Oncol 2011; 23: 373 - 378). Possible symptoms of mediastinal liposarcoma are dyspnea, wheezing, chest pain, cough, superior vena cava syndrome, and weight loss (Macchiarini P et al. Lancet Oncol 2004; 5: 107 - 118).

[en] Mesenchymal tumors in childhood comprise benign and malign entities and differ regarding typical sites of manifestation, age peak and clinical symptoms. In some cases biopsy is mandatory. If nephroblastoma is a possible diagnosis, biopsy must be avoided by all means in order to avoid biopsy tract metastasis. Imaging is used to narrow the differential diagnosis, describe the exact extent of the lesion and deliver complete staging. In pediatric patients sonography and MRI are the most important imaging modalities. Low-dose CT of the thorax serves for assessment of possible pulmonary metastases. (orig.)

[en] PURPOSE: To measure the accuracy of laser-guided punctures and to evaluate the usefulness of the developed laser-guided system. MATERIAL AND METHODS: The study included 67 patients referred for computed-tomography-guided puncture. The majority of the punctured lesions were located in the chest (28 patients) or abdomen (19 patients). The mean diameter of the lesion was 3.1 cm, and the mean path length was 6.8 cm. The laser guide was movable along a horizontal or vertical rail and not physically connected to the CT unit. The angle of insertion was entered manually into the display of the unit by the interventional radiologist. A prospective multicenter trial was carried out. RESULTS: A mean of 1.1 needle passes were necessary to reach the target, and in 55 (84.6%) of the patients the target was reached on the first needle pass. The mean deviation of the needle from the preselected angle was 1.8 degrees. The mean targeting time (from the initial localizing scan until the needle was in the target) was 15.6 min. In every case, both the usefulness and the ease of use of the laser guidance system were subjectively evaluated on a 5-point scale; the mean usefulness score was 4.5, while the mean ease of use score was 4.7. CONCLUSION: Different users at four different centers found the laser guidance system useful and easy to use. A high level of accuracy of the puncture angle was obtained in most cases

[en] We examined to what degree the visualization of anatomic structures in the human knee is improved using 3.0-T magnetic resonance imaging (MRI) and many element RF receive coils as compared to 1.5 T. We imaged 20 knees at 1.5 and 3.0 T using T2-weighted STIR, T2-weighted gradient echo, T1-weighted spin-echo, true-FISP and T2-weighted fast spin echo techniques in conjunction with 32-element RF coil arrays. The 3.0-T examination was considerably faster than its 1.5-T counterpart. A superior subjective visibility at 3.0 T vs 1.5 T was found in 27 of 50 evaluated structures (meniscus, ligaments) with the exception of true-FISP techniques. The 3.0-T examination provided a better visibility (evaluated by blinded consensus-reading by two radiologists) of small structures such as the ligamentum transversum genu. Also, cartilage was better delineated at 3.0 T. A 23% increased average signal-to-noise ratio as assessed using a temporal filter was observed at 3.0 T as compared to 1.5 T. At 3.0 T, imaging of the human knee is faster and results in a subjective visibility of anatomic structures that is superior to and competitive with 1.5 T. (orig.)

[en] Transthoracic echocardiography is usually the initial diagnostic test in patients with a suspected cardiac mass. However, this technique is restricted by its small field of views and insufficient acoustic window in some patients. Magnetic resonance imaging (MRI) and, since its introduction, multislice spiral computed tomography allow for detailed delineation of intra and pericardiac tumors, their extent, and their influence on cardiac function. Primary benign and malignant cardiac tumors have several characteristic features in MR imaging. Assessment of such features may narrow down the differential diagnosis or even allow for reliable diagnosis in selected cases. Many such features can also be assessed using MSCT. This article provides an overview of examination protocols of MRI and CT for cases in which a cardiac mass is suspected and describes the appearance of primary and secondary cardiac masses as well as intracavitary thrombi. (orig.)

[en] Purpose: To evaluate the prototype of a new optical target device for CT-guided punctures and interventions. Methods: An optical target device for CT-guided punctures was applied in 24 interventions. The system consists of a laser target device mounted on a stand. The biopsy needle is adjusted according the course of a laserbeam. The target angle has to be adjusted on the laser unit. The laser carrier can be moved along an 90 -angled rail, allowing punctures from any angle in plane. Furthermore, angulation in the z-plane is possible, supporting interventions with gantry tilt. Size and depth of the target lesions, the planned and the actual angle of the inserted needle, the numbers of corrections of the needle position, and the time required for the puncture were evaluated. The user rated the benefit of the system and the ease of the application. Results: All 24 interventions were carried out successfully. The mean difference between the planned and the actual angle of the needle was 1.3 (SD: 0.7 ). The system was considered as easy to handle and as a valuable aid. Conclusions: The laser target device is a simple navigation system which allows accurate positioning of a needle. Requiring an acceptable low preparation time, it easily can be integrated into the procedure. (orig.)

[en] Purpose: to evaluate the impact of magnetic resonance imaging (MRI) with use of True-FISP sequences in the evaluation of inflammatory bowel-wall changes in children and adolescents with Crohn's disease. Furthermore, the diagnostic procedure in children and adolescents with chronic inflammatory bowel disease (IBD) will be discussed in light of the relevant literature. Material and methods: twenty-four children and adolescents aged between 7 and 21 years with suspected or known IBD underwent MRI on a 1.5T-scanner (Philips ACS-NT, Best, Netherlands). One hour after 11 of a 2.5% mannitol solution was given orally, MR imaging was performed using coronal HASTE-M2D, coronal fat-suppressed T2-TSE, axial dynamic T1-weighted GE-sequences before and after i.v.-contrast material injection (0.1 mmol/kg Gd-DTPA) and using a 2D-balanced-FFE-sequence (True-FISP) before and after i.v.-contrast material injection in coronal and axial planes. The MR-images were correlated with endoscopy and the clinical findings. In 14 patients, a recently performed conventional radiographic enteroclysis was available. Each performed MRI sequence was evaluated by three experienced radiologists regarding the sensitivity and specificity of each sequence in the detection of inflammatory bowel wall changes. In addition, the image quality was assessed regarding the different tissue contrasts and the susceptibility to artifacts. The distension of the bowel wall and the patients' acceptance of the MRI examination were recorded. Results: with a sensitivity in detecting inflammatory small bowel changes of 93.3% (axial pre-contrast, coronal post-contrast) and 100% (axial post-contrast, coronal pre-contrast), the True-FISP outnumbers the other performed sequences (T1 = 80%, HASTE = 13.3% and T2-TSE = 53.3%). The difference between True-FISP and contrast-enhanced T1 was not statistically significant, whereas the difference between True-FISP and HASTE and T2-TSE, respectively. (orig.)