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Background: Iodinated X-ray contrast media (CM) are recognized worldwide to be among the safest and most widely used injectable drugs. However, adverse drug reactions (ADRs) may still occur, ranging in severity from minor disturbances to severe and potentially fatal complications. Purpose: To prospectively determine the incidence and characteristics of acute ADRs during clinical utilization of a single nonionic monomeric contrast agent, iopromide, in routine radiological practice in a large number of nonselected patients. Material and Methods: 74,717 patients were enrolled in a prospective international postmarketing surveillance registry with iopromide (Ultravist; Bayer Schering Pharma AG, Berlin, Germany). A standardized questionnaire was used to collect the following patient information from 762 centers in 27 countries: baseline demographics, risk factors, premedication regimen, type of examination, route of injection, volume and selected concentration of iopromide, and overall tolerance to CM (utilizing specific criteria and descriptors). Results: The overall rate of ADRs, including tolerance indicators (TI) (i.e., heat sensation and pain at the injection site), was 2%; when TIs were excluded, the rate was 1.5%. Fourteen serious adverse reactions were reported (rate 0.02%), of which none were fatal. There was a higher incidence of ADRs among women and for the age group ranging between 18 and 30 years. Patients with established risk factors, such as a history of previous CM reaction or allergic diathesis (7.4% and 4.1%, respectively), were at an increased risk for developing an ADR when compared to patients without risk factors (1.2%). The incidence of ADRs was not altered by the use of premedication. Conclusion: The safety of iopromide in routine clinical practice was shown to be comparable to the published safety profiles of other nonionic iodinated contrast agents. Adverse drug reaction rates were affected by age, gender, and risk factors (especially previous CM reactions or allergies), but not by premedication.

Computer-aided transfer of questionnaire data simplifies the analysis of questionnaires. We present a solution based on an inexpensive barcode pen and its decoder, the software tool Barcode Wizard included in CorelDRAW, and a self-developed application written using Microsoft Visual Basic for Applications. The barcode may be provided on the questionnaire or on a transparency. Error correction is done by means of two different procedures. The present solution can be applied while looking over the completed questionnaire and thus allows time-saving, economic, and precise data transfer from the completed questionnaire directly into computer software.

Combined MRI/PET enables the acquisition of a variety of imaging parameters during one examination, including anatomical and functional information such as perfusion, diffusion, and metabolism.The present article summarizes these methods and their applications in multiparametric imaging via MRI/PET.Numerous studies have shown that the combination of these parameters can improve diagnostic accuracy for many applications, including the imaging of oncological, neurological, and inflammatory conditions. Because of the amount and the complexity of the acquired multiparametric data, there is a need for advanced analysis tools, such as methods of parameter selection and data classification.Currently, the clinical application of this process still has limitations. On the one hand, software for the fast calculation and standardized evaluation of the imaging data acquired is still lacking. On the other hand, there are deficiencies when comparing the results because of a lack of standardization of the assessment and diagnostic procedure.

Besides ischemic heart disease cardiomyopathies are common causes of heart failure and sudden cardiac death.The diagnostic spectrum in cardiomyopathies comprises non-invasive and invasive examination techniques.The exact verification of certain cardiomyopathies necessitates knowledge of the latest classification of cardiomyopathies as well as dedicated examination protocols.Modern imaging modalities, such as echocardiography and cardiac magnetic resonance imaging (MRI) have emerged as useful imaging tools in the investigation of patients suspected of having many different types of cardiomyopathies.Based on a better understanding of the underlying pathophysiology several diagnostic criteria have been defined using cardiac MRI. In particular there is an increasing importance of cardiac MRI in the description of patients with restrictive and unclassified cardiomyopathies.Echocardiography still remains the modality of choice in the diagnostics of unclear left ventricular heart failure. Further diagnostic work-up should include cardiac MRI in case of any lack of clarity.

PURPOSE: To assess the visualisation of the anal sphincter by means of an intravaginal surface coil. METHODS: MR imaging was performed using a 1.0 T unit. In 10 females (6 nullipara, one primipara without and three primipara with postpartum faecal incontinence) a surface coil, originally designed for endorectal use, was placed into the vagina. Transverse oblique T1-weighted spin echo and double echo turbo spin echo sequences with T2- and proton density-weighting were acquired parallel to the puborectal, rectococcygeal and anorectal planes. Three readers analysed the images in consensus. RESULTS: The anatomic structures of the external and internal sphincter as well as the mucosa were differentiated in all cases with a good contrast. The best results were yielded by the proton density weighting. In one case of faecal incontinence a sphincter defect after repair of a complete rupture of the anal sphincter was shown. In another case irregularities in the structure of the external sphincter and perineum were visualised. CONCLUSION: Intravaginal surface coil imaging seems a well-tolerated novel method for the evaluation of the anal sphincter tissues in truly anatomical states. Due to its capability to depict subtle tissue structures as well as pathologic irregularities, it might become a potential tool in the diagnosis and operation planning of postpartal faecal incontinence.

Die Rate erfolgloser Probelaparotomien zur intraoperativen Lokalisation von Gastrinomen betragt 30-35% und von Insulinomen 7-10%. Praoperative Lokalisationsstudien sind daher weiterhin essentiell. Die perkutane Ultraschalluntersuchung ist wegen ihrer ungenugenden Treffsicherheit nicht wegweisend. Bei Verfugbarkeit der Endosonographie kann die Sensitivitat auf 80% bei der Tumordetektion im Pankreas gesteigert werden. Vergleichbare Informationen kann auch eine subtile intraoperative Sonographie bei tiefgelegenen endokrinen Tumoren des Pankreas geben. Die Computertomographie (CT) des Abdomens ist unentbehrlich, da sie einen kompletten Uberblick uber das Zielorgan, die anatomische Topographie des Oberbauches und insbesondere einen etwaigen Metastasenbefall der Leber gibt. Die Magnetresonanztomographie hat ein groses technisches Entwicklungspotential, bietet derzeit aber noch keine gesicherten Zusatzinformationen gegenuber der CT. Die Arteriographie hat aufgrund der Hypervaskularisation von Insulinomen hier immanente Vorteile. Demgegenuber bereiten Gastrinome aufgrund ihrer Kleinheit und haufig extrapankreatischen Lage auch angiographisch Probleme. Die Kombination von Arteriographie und CT im Rahmen einer CT-Arteriographie der Leber stellt 95% der Lebermetastasen von Insulinomen und Gastrinomen dar und ist hier von grosem Wert. Die selektive portale Venenblutentnahme ist ein sensitives Verfahren fur die Lokalisation endokriner Tumoren des Pankreas. Die Methode bietet jedoch neben der Invasivitat noch Probleme bei der Inteφretation der Ergebnisse durch die variable venose Drainage des Pankreas. Die Somatostatinrezeptorszintigraphie kann Tumoren mit einer hohen Zahl von Somatostatinrezeptoren darstellen. Dies ist aber nur bei 40-80% der neuroendokrinen Tumoren des Pankreas der Fall. Therapeutisch kann die Angiographie neben der selektiven Embolisation massiv blutender Dunndarmtumoren mit der Chemoembolisation eine effektive und komplikationsarme Methode zur symptomatischen Therapie von Lebermetastasen endokriner Tumoren anbieten.

Ultrasound remains the most readily available and least expensive of the imaging techniques used in assessment of the upper abdomen. Ultrasound is very useful in the detection of pancreatic tumors as well as in the evaluation of the extent of the disease. If ultrasound fails technically or is inconclusive, CT is recommended. Determination of CA 19-9 may help to decide whether ultrasound should be followed by CT or other examinations (51). Patients with any equivocal or inconclusive abnormality on ultrasound or CT should undergo ERCP. Even when ultrasound and CT of the pancreas appear normal there may be an indication for performing ERCP if the clinical suspicion of pancreatic cancer is still strong (52). Angiography is a reliable method of assessing major vascular tumor involvement, which to most surgeons would be a sign of unresectability. Although for some investigators CT is superior to angiography in assessing vascular involvement, angiography is performed preoperatively in many cases because it delineates the vascular anatomy, which can be abnormal in up to one third of patients. Percutaneous biopsy is an important technique for confirming the radiologic diagnosis of unresectable pancreatic carcinoma, particularly for differentiating pancreas carcinoma from other focal pancreatic lesions such as islet cell tumor, lymphoma, and chronic pancreatitis.

The study was designed as a feasibility trial to evaluate the use of GP IIb/IIIa blockade in connection with drug eluting stents, bare stents and PTA only. Sixty patients with current ulcers were randomly assigned to receive abciximab plus a sirolimus coated stent (N.=14), abciximab plus a bare stent (N.=16), abciximab plus PTA (N.=14) and PTA alone (N.=19). Angiographic control was performed at two and six months. Recanalization was successful in all cases. Two month restenosis rate was 9%, 45.5%, 67% and 46%. At six month follow-up restenosis rate was 9%, 67%, 75% and 58%, respectively; 14% of all patients had major amputations within six months. Adjunctive administration of abciximab during peripheral arterial intervention below the knee was found to be safe. Sirolimus coated stent administration was followed by a higher patency rate.

This experimental study was designed to define the potential value of a mid-infrared holmium laser in the free running mode for angioplasty. Immediately after removal, fresh normal and diseased human cadaveric arteries were irradiated under saline with a Ho:YAG laser (wavelength 2.13 μm). The laser was pulsed at 3 Hz, 250 μs pulse width and fluences of 10 to 40 J/cm2. The laser beam was coupled to ring catheters with multiple low-OH quartz fibers. The tip of the delivery device was held in direct contact with the vessel surface with the laser beam oriented perpendicularly. Ablation of atherosclerotic plaque was accomplished at an ablation threshold of 10 J/cm2. The ablation rate was 2.1 to 8.3 μm/pulse. Removal of calcified plaque was only partially effective. There were marked thermal effects with vacuolizations extending up to 1505 ± 178 μm into the adjacent tissue. Laser light at the mid-infrared wavelength of 2.13 μm is supposed to be attractive as it is readily absorbed in water and can easily be transmitted through optical fibers. However, Q-switching seems to be essential to minimize thermal side effects and to make effective ablation of calcium possible.

Analysis of enhancement characteristics and T 2 signal intensity (SI) of breast cancers and normal breast parenchyma on MR imaging (MRI) before and after neoadjuvant treatment (NT) to improve the assessment of therapy response.Retrospective data analysis of 43 consecutive patients (mean age 49.9 years) with invasive breast cancers (T2 /T3) who received NT. Evaluation of breast MRI before and after NT with assessment of therapy response according to RECIST criteria as well as calculation of the maximum initial enhancement (Enh (max)), delayed enhancement (Enh (post)) and T 2 SI by ROI analyses of breast cancers and breast parenchyma. Comparison of therapy response and enhancement characteristics.Therapy response on MRI: 16.3 % (n = 7) complete remission (CR (MRT)), 53.5 % (n = 23) partial remission (PR (MRT)), 27.9 % (n = 12) stable disease (SD (MRT)) und 2.3 % (n = 1) progressive disease (PD (MRT)). Breast cancers showed a significant decrease in Enh (max) and T 2 SI as well as a significant increase in Enh (post) after NT (p0.01). Not any SI parameter of normal breast parenchyma showed a significant change after NT (p0.05). All cases with CR (MRT) had wash out or plateau shape of the SI time curve before NT and showed continuous enhancement thereafter.Breast MRI shows significant changes in enhancement characteristics and T 2 SI of breast cancers after NT, whereas normal breast parenchyma remains unchanged. SI data could possibly help to improve the assessment of therapy response by MRI. Prospective trials with larger study cohorts and MRI monitoring during NT are necessary to validate these results.

To determine whether lesion scoring allows valid BI-RADS ((R)) classification and prediction of malignancy of breast lesions detectable solely with MRI.Retrospective analysis of 86 patients who underwent MRI-guided localization and excisional biopsy of 100 breast lesions detectable only with MRI. Breast MRI was performed at 1.5 Tesla by means of a T 1w dynamic GE sequence. The positive predictive value (PPV) for malignancy was calculated for each score criterion separately, for the total score, and for corresponding BI-RADS classes. The PPV was correlated with histology.31% (31/100) of breast lesions detectable only with MRI were malignant. Of the single score criteria only the lesion morphology criterion was significantly correlated with malignancy. The malignancy rate according to the breast MRI score was 0% for score 3, 18.2% for score 4, 32.1% for score 5 and each 50% for lesions of score 6 and 7. After translation into BI-RADS the malignancy rates were 0% for BI-RADS 3, 24.6% for BI-RADS 4 and 48.5% for BI-RADS 5 lesions. The thus defined BI-RADS classes were significantly correlated with malignancy.The combination of different lesion criteria to form a total breast MRI score and its translation into BI-RADS is useful in case of lesions detectable only with MRI. It enables standardized BI-RADS classification with satisfying PPV of malignancy for each BI-RADS class. Because of their low malignancy rate (18.2%), we suggest classifying lesions with a breast MRI score of 4 points as BI-RADS 4a.

If diagnostic imaging during pregnancy is performed, potential risks not only for the mother but also for the fetus have to be considered. Ultrasonography should be performed primarily because it is harmless for the fetus. Other imaging modalities like x-ray, computed tomography (CT) and magnetic resonance imaging (MRI) should be reserved for cases in which results of ultrasonography are inconclusive and patient care depends on further imaging. If pulmonary disease is suspected (e. g. pneumonia) chest x-ray should be performed. CT should be considered if chest x-ray is nondiagnostic or inadequate (e. g. suspicion of pulmonary embolism). In patients with abdominal symptoms the indication either for CT or MRI depends on the presumed disease. Every abdominal CT during pregnancy should include an estimation of radiation dose. Dose estimation is not necessary after CT of the chest. In case of pelvic disease in particular concerning the ovaries and the uterus as well as fetal imaging MRI is the method of choice. Contrast media should only given intravenously when a compelling clinical indication exists and the potential benefit to the patient outhweights the potential risk to the fetus.

Evaluation of a newly developed Clip (Tumark Professional) for MRI-guided lesion localization after MRI-guided vacuum-assisted biopsy (VAB) with regard to the exactness of positioning, migration, and visibility on mammography (MG), ultrasound (US) and MR imaging (MRI).27 consecutive patients with 29 suspicious breast lesions detected with MRI were prospectively evaluated. The location of the lesion was determined with Tumark (Somatex, Teltow, Germany) after MRI-guided VAB. The distance between the clip and lesion was measured via MRI. The qualitative visibility of the clip was assessed by means of a 5-point scale from very good (1 point) to not visible (5 points). The analysis was performed for MG, US and MRI separately. Clip movement was measured via MG.9 lesions were malignant (31%). All but one lesion (96%) were able to be localized exactly with a clip-lesion distance ofor = 10 mm. The Tumark was visible in 27 cases (93.1%) in US and in 25 cases (86.2%) in MRI. The visibility of the clip was moderate for both modalities (mean 3.2 points). Its visibility in MG was always very good (1 point). The clip position was stable at the time of short term follow-up (1 - 7 months; mean deviation 4.5 mm).Precise positioning of the Tumark Professional is usually possible. The clip is mostly visible in US. At the time of short-term follow-up, there was no relevant movement. Therefore, Tumark seems to be suitable for MRI-guided lesion localization after MRI-guided VAB of suspicious breast lesions. Further improvement of US visibility would be beneficial.

Objective: To evaluate diffusion-weighted imaging (DWI) in the response monitoring of hepatocellular carcinoma (HCC) treated with the oral multikinase inhibitor Sorafenib.

Only few studies have been reported on DTI applications focused on human kidney. The restriction of these studies to a single breath-hold limits the possible spatial resolution and the precision of the diffusion measurement. The aim of the present study was to evaluate the feasibility of respiratory triggered DTI in the assessment of the fiber architecture of the renal medulla in healthy volunteers.

To evaluate the impact of laser ablation of arteriosclerotic material on the long-term results of transluminal angioplasty, 103 patients were treated by laser-assisted recanalization of peripheral arterial occlusion and followed-up for 6 and 12 months. Two pulsed laser systems (308 nm-excimer laser and 504 nm-dye laser) were tested. Laser energy was transmitted via wire-guided 4.5-, 7- and 9-French multifiber catheters. Stand-alone laser angioplasty was possible in 22% of the patients, especially in the popliteal and the lower-limb arteries. Compared to the results of balloon dilatation in the literature, the clinical success rate at 6 and 12 months after the treatment was better in occlusions with a length between 6 and 10 cm, however no improvement was seen in either shorter or longer occlusion. Due to the limited size of percutaneously applicable catheters, laser treatment and pretreatment seemed to be of most benefit in distal femoropopliteal arteries and in lower-limb arteries. Clinical improvement after revascularization depends on a sufficient run-off in branching vessels distal to the recanalized artery segment.

This in-vivo study quantifies the accuracy of automated pulmonary nodule volumetry in reconstructions with different slice thicknesses (ST) of clinical routine CT scans. The accuracy of volumetry is compared to that of unidimensional and bidimensional measurements.28 patients underwent contrast enhanced 64-row CT scans of the chest and abdomen obtained in the clinical routine. All scans were reconstructed with 1, 3, and 5 mm ST. Volume, maximum axial diameter, and areas following the guidelines of Response Evaluation Criteria in Solid Tumors (RECIST) and the World Health Organization (WHO) were measured in all 101 lesions located in the overlap region of both scans using the new software tool OncoTreat (MeVis, Deutschland). The accuracy of quantifications in both scans was evaluated using the Bland and Altmann method. The reproducibility of measurements in dependence on the ST was compared using the likelihood ratio Chi-squared test.A total of 101 nodules were identified in all patients. Segmentation was considered successful in 88.1% of the cases without local manual correction which was deliberately not employed in this study. For 80 nodules all 6 measurements were successful. These were statistically evaluated. The volumes were in the range 0.1 to 15.6 ml. Of all 80 lesions, 34 (42%) had direct contact to the pleura parietalis oder diaphragmalis and were termed parapleural, 32 (40%) were paravascular, 7 (9%) both parapleural and paravascular, the remaining 21 (27%) were free standing in the lung. The trueness differed significantly (Chi-square 7.22, p value 0.027) and was best with an ST of 3 mm and worst at 5 mm. Differences in precision were not significant (Chi-square 5.20, p value 0.074). The limits of agreement for an ST of 3 mm were +/- 17.5 % of the mean volume for volumetry, for maximum diameters +/- 1.3 mm, and +/- 31.8 % for the calculated areas.Automated volumetry of pulmonary nodules using OncoTREAT has a conformable accuracy for an ST of 3 mm and 1 mm and is even more accurate for an ST of 5 mm than unidimensional or bidimensional measurements. A difference of more than +/- 17.5% occurs with a probability of less than 5% at an ST of 3 mm.

To describe typical morphological patterns of abacterial prostatitis using magnetic resonance imagine (MRI) in chronic pelvic pain syndrome patients including spectroscopy.18 patients (age range between 25 and 67 years, average 46.2 years) with recurrent chronic pelvic pain syndrome for at least 3 months were evaluated clinically in the urological department and included if there were no suspicious findings from endorectal digital palpation and if their PSA values were5 ng/ml. A retrospective analysis of these 18 patients with 30 contrast-enhanced MRI investigations with endorectal coils in 28 of 30 cases was performed with a 1.5T MRI. T 2w signal intensity (SI) and spectroscopy data (9 / 18 patients) were acquired for the normal peripheral zone, the central zone, for the peripheral zone suspected of inflammation and for the muscle including SI ratios for the unaltered and the suspicious inflammatory peripheral zone.Typical MR patterns of signal alterations suspected of inflammation of CPPS patients were able to be detected as T 2w hypointense triangular, stringy (n = 12, 66.6 %) contrast-enhancing signal alterations without a nodular shape with well circumscribed margins of the capsula and without pericapsular signal alterations. In 6 patients changes also had a triangular but more homogeneous aspect (33.3 %). Three patients had an additional periurethral uptake (16.6 %). T 2w SI measurements and T 2w SI ratios showed much lower values for the peripheral zone suspected of inflammation as compared to the normal peripheral zone of the prostate (277.29 STD 77.5 to 432.9 STD 112.02 and 4.94 STD 1.47 to 7.58 STD 2.01 respectively). The spectroscopic analysis of the signal alterations suspected of inflammation showed normal Cholin+Creatin/Citrate SI ratio values in 3 patients (SI0.5), ratios suspected of low grade cancer in 3 patients (SI 0.5 and0.7) and ratios suspected of intermediate grade prostate cancer in 3 patients (SI0.7 and3.0).We saw typical MR patterns in CPPS patients. However, spectroscopy can mimic findings of cancer so that the knowledge of typical morphological patterns and a solid clinical evaluation play a major role in the diagnosis of CPPS.

The aim of the study was to assess the feasibility and additional diagnostic information of cardiac MRI as a supplement to state-of-the-art MR angiography (MRA) in the case of vascular risk patients. Therefore, the prevalence of delayed myocardial enhancement (DE) was determined in patients suffering from peripheral artery disease (PAD) and a clinical follow-up was evaluated after 2 years.87 consecutive patients (ages 66 +/- 10 years, 67 males) with symptomatic peripheral arterial occlusive disease (n = 68) or abdominal aortic aneurysm (n = 19) were examined using delayed cardiac enhancement (DE) within the clinical indication of MRA at a 1.5T system. A follow-up examination was carried out two years later (24 months +/- 4 months) with regards to cardiac events (cardiac death, myocardial infarction or acute coronary syndrome, heart insufficiency, coronary revascularization).In total, 40 / 87 patients had myocardial infarctions shown in MRI (46 %). In 25 patients (29 %), the myocardial infarction was already known, while in 15 patients (17 %) an occult progressing infarction was diagnosed (38 % of the myocardial infarcts). Follow-up data was able to be obtained after 2 years for 82 patients. 15 patients had a major cardiac event during the follow-up period, and 10 (67 %) of them already showed DE in the MRI. In the group with occult progressing infarctions, cardiac events occurred in 40 % (6 / 15 patients, cardiac death n = 1, ischemia n = 4, heart insufficiency n = 1, bypass n = 1), in patients with known infarction in 17 % (4 / 23 patients, cardiac death n = 1, ischemia n = 3, bypass n = 2) and in 11 % of patients without myocardial scars (5 / 44 patients, cardiac death n = 1, ischemia n = 2, heart insufficiency n = 2).Cardiac MRI in combination with MRA was feasible and showed a high prevalence of known and unexpected myocardial infarctions. This was of prognostic relevance in the follow-up 2 years later. Therefore, this enables important additional information regarding to the risk stratification and eventually targeted therapy in risk patients with PAD.

Prostate cancer continues to be the third leading cancer-related mortality of western men. Early diagnosis of bone metastasis is important for the therapy regime and for assessing the prognosis. The standard method is bone scintigraphy. Whole-body MRI proved to be more sensitive for early detection of skeletal metastasis. However, studies of homogenous tumor entities are not available. The aim of the study was to compare bone scintigraphy and whole-body MRI regarding the detection of bone metastasis of prostate cancer.14 patients with histologically confirmed prostate cancer and a bone scintigraphy as well as whole-body MRI within one month were included. The mean age was 68 years. Scintigraphy was performed using the planar whole-body technique (ventral and dorsal projections). Suspect areas were enlarged. Whole-body MRI was conducted using native T 1w and STIR sequences in the coronary plane of the whole body, sagittal imaging of spine and breath-hold STIR and T 1w-Flash-2D sequences of ribs and chest. Bone scintigraphy and whole-body MRI were evaluated retrospectively by experienced radiologists in a consensus reading on a lesion-based level.Whole-body MRI detected significantly more bone metastasis (p = 0.024). 96.4 % of the demonstrated skeletal metastases in bone scintigraphy were founded in whole-body MRI while only 58.6 % of the depicted metastases in MRI were able to be located in scintigraphy. There was no significant difference regarding bone metastasis greater than one centimeter (p = 0.082) in contrast to metastasis less than one centimeter (p = 0.035). Small osteoblastic metastases showed a considerably higher contrast in T 1w sequences than in STIR imaging. Further advantages of whole-body MRI were additional information about extra-osseous tumor infiltration and their complications, for example stenosis of spinal canal or vertebral body fractures, found in 42.9 % of patients.Whole-body MRI using native STIR and T 1w sequences is superior to bone scintigraphy for the detection of small bone metastasis of prostate cancer. Simultaneous clarification of associated complications demonstrates further advantages.

The aim of this study was to evaluate and discuss economic aspects of whole-body MRI and PET/CT in oncologic staging. Considerations from the perspective of the health care system, the radiologist, and the patients are presented.Costs of both whole-body techniques are compared with the conventional radiologic diagnostic recommendations of the AWFM (Arbeitsgemeinschaft Wissenschaftlich Medizinischer Fachgesellschaften) in oncologic staging of the five most frequent tumor entities. Temporal and monetary aspects are calculated. Invasive, endoscopic, and endosonographic techniques are regarded as essential and cannot be replaced by other techniques. Thus only the minimal potential for cost reduction is quantified.In the German system there is no cipher to correctly balance whole-body MRI and PET/CT. Using the frequently applied ciphers 5700-5730 and 5378, 5489 (factor 1.0) total costs were 440.45 euros, and adding the cipher for additional series 545.37 euros (60 min examination time) for whole-body MRI and 774.74 euros (879.66 euros) (60/90 min examination time) for whole-body PET/CT. Using the common factor 1.8 costs were 981.66 and 1583.38 euros. On the basis of a simple full cost analysis total costs of whole-body PET/CT were higher than of whole-body MRI by a factor of about 2.0 (about 1123 vs 575 euros). There were substantial monetary and temporal differences between tumor entities. In extended bronchial carcinoma 375.32 euros and 55 min can be saved using whole-body MRI in comparison to conventional recommended techniques and using whole-body PET/CT 88.14 euros and 45 min. In tumor entities of lower stages with thus less essential radiologic diagnostics the potential for cost reduction is substantially lower.Whole-body imaging techniques make it possible to reduce the number of necessary separate radiologic examinations and thus time in oncologic staging. A substantial reduction of health care costs seems to be possible in many tumor entities but differences between different tumor entities are decisive.

The aim of the present study was to determine the correlation of myocardial perfusion MR imaging (MPMRI) and coronary angiography for the detection of flow-limiting stenosis in symptomatic patients with known coronary artery disease and a history of intervention.MPMRI was performed in 51 symptomatic patients (44 male, 64.7 +/- 9.5 years) with known coronary artery disease and a history of stent implantation (between 5 years and 2 weeks prior to MRI). Malperfused myocardial regions were correlated with findings of coronary angiography. A stenosis of70% was regarded as hemodynamically significant.In MPMRI 37 patients (73%) showed a stress induced perfusion deficit. In 35 of these patients coronary angiography revealed a stenosis of70 %. A total of 38 patients (75%) showed stenoses of70%. MPMRI yielded a sensitivity of 92% with a specificity of 85 %. The positive predictive value was 95 % and negative predictive value was 79%. The assignment of malperfused segments to coronary artery territories was carried out according to the standardized myocardial model of the American Heart Association (sensitivity/specificity was 59/85% for RCA, 79/81% for LAD and 54/68 % for LCX).MPMRI is a suitable non-invasive method for detecting flow-limiting coronary artery stenoses in patients with a history of stent implantation.

To evaluate an improved method of dynamic magnetic resonance (MR) nephrography with short acquisition time and compensation of breathing motion for assessment of renal excretion and split renal function in children with anomalies of the urinary tract.A protocol for dynamic MR nephrography was implemented using a T1-weighted navigator-gated TurboFLASH sequence (TR/TE 498 ms/1.25 ms, saturation recovery time 300 ms, flip angle 8 degrees ). After bolus injection of 0.05 mmol/kg gadolinium dimeglumine (Gd-DTPA), split renal function was determined from the contrast-medium excretion. In 20 patients (ages between 3 months and 14 years), dynamic MR nephrography and MAG3 radionuclide scintigraphy as the gold standard were performed.In all children, T1-weighted images were able to be recorded over 40 minutes at a nearly identical diaphragm position using the TurboFLASH sequence, thus allowing for exact region-of-interest analysis of the excretion and split renal function. The course of the contrast-medium concentration was able to be measured in the renal pelvis with good accuracy due to the high spatial resolution and the lack of breathing artifacts. Excellent correlation to the MAG3 scintigraphy was demonstrated for the excretion and split renal function (correlation coefficient: 0.975).Dynamic MR nephrography allows for reliable assessment of renal function in children with anomalies of the urinary tract with higher spatial resolution as compared to radionuclide scintigraphy.

Due to technical innovations in sectional diagram methods, whole-body imaging has increased in importance for clinical radiology, particularly for the diagnosis of systemic tumor disease. Large numbers of images have to be evaluated in increasingly shorter time periods. The aim was to create and evaluate a new software tool to assist and automate the process of diagnosing whole-body datasets.Thirteen whole-body datasets were evaluated by 3 readers using the conventional system and the new software tool. The times for loading the datasets, examining 5 different regions (head, neck, thorax, abdomen and pelvis/skeletal system) and retrieving a relevant finding for demonstration were acquired. Additionally a Student T-Test was performed. For qualitative analysis the 3 readers used a scale from 0 - 4 (0 = bad, 4 = very good) to assess dataset loading convenience, lesion location assistance, and ease of use. Additionally a kappa value was calculated.The average loading time was 39.7 s (+/- 5.5) with the conventional system and 6.5 s (+/- 1.4) (p0.01) with the new software tool. For the different regions (conventional system/new software tool), the time reduction for readers 1, 2, and 3 were as follows: in the head region 35.9 % (p0.01)/49.9 % (p0.01)/54.3 % (p0,01), in the neck region 48.5 % (p0.01)/52.6 % (p0.01)/59.4 % (p0.05), in the thorax region 59.1 % (p0.01)/56.2 % (p0.05)/62.1 % (p0.05), in the abdominal region 61.9 % (p0.01)/62.7 % (p0.05)/47.9 % (p0.01) and in the pelvis region 73.1 % (p0.01)/63.7 % (p0.05)/55 % (p0.01), respectively. 148.2 s (+/- 94.8) compared to 2.5 s (+/- 0.5) were required to retrieve a previously described finding (p0.01). With and without the new software tool the same number of metastases was found (p0.01, k0.9). The qualitative analysis showed a significant advantage with respect to convenience (p0.01, k0.9).Use of the new software can achieve a significant time savings when working with whole-body datasets with a constant quality of findings and a significant advantage with respect to convenience. As a result, the problem of evaluating examinations with thousands of images can be approached systematically.

Evaluation of bipolar radiofrequency (RF) ablation using internally cooled electrodes in an ex-vivo experiment.Bipolar RF ablations (n = 154) were performed in ex-vivo bovine liver. Both electrodes with a total length of the active tip of 4 cm were located on the same shaft of an internally cooled applicator. The power output was systematically varied between 20 and 100 watts (W). The energy application was continuous or modulated depending on the tissue resistance. In relationship to the maximum power output, the volume of coagulation was assessed.In continuous energy application the induced volume of coagulation was increased at lower power outputs up to 33.7 cm (3) (20 watts). Parallel to an increased volume of coagulation, the required duration of energy application was increased up to a maximum of 51.6 minutes. Modulation of the power output as a function of the tissue resistance enabled application of a wide range of power outputs (40 - 75 watts) leading to a comparable extent of coagulation with a maximum of 14.9 cm (3) (10 min.), 16.8 cm (3) (15 min.), and 19.1 cm (3) (20 min.).Continuous application of RF energy leads to an inverse relationship between volume of coagulation and power output. Modulation of the power output as a function of the tissue resistance enables application of a wider range of power outputs compared to continuous application of RF energy.

The purpose of this study was to establish a reliable and simple parameter for alignment evaluation and the evaluation and optimization of state-of-the-art contrast-enhanced examination protocols for (18)F FDG-PET/CT.44 consecutive patients were referred to 4 examination protocols. Group A and B underwent single-phase, contrast-enhanced CT (90 s delay) performed either during free shallow breathing (FA; group A) or normal expiration (NormExp; group B). Groups C and D underwent arterial and portal venous multiphase examinations performed during FA (group C) or during NormExp (group D) followed by a low-dose CT scan for attenuation correction. Organ displacement in the cranio-caudal direction was correlated with a 3D-vectorial shift. For alignment evaluation discrepancies with respect to size and liver location, the spleen and kidneys were calculated. Additionally, the groups were compared with regard to the presence of CT artifacts.Cranio-caudal organ shift and 3D-vectorial shift showed a high correlation (r0.8). Single-phase CT scans performed during NormExp yielded better image quality (p0.001) and alignment (p0.01 for liver, spleen and right kidney) than those performed during FA. Differences in organ size did not differ during FA and NormExp. Depending on the evaluated organ, breathing and contrast protocol misalignment was in the cranio-caudal direction 0-27 mm (mean: 6.8; standard deviation: +/- 4.9) in multiphase CT compared to 0 - 11 mm (mean: 4.5 +/- 2.3) in single-phase examinations.1. Organ shift in the cranio-caudal direction is a good and simple parameter for alignment evaluation. 2. Alignment and CT quality are best in expiration protocols. 3. Despite comparatively low alignment quality, integrated multiphase CT examinations show acceptable quality and alignment.

To examine patients with peripheral-arterial-occlusive-disease (PAOD) for systemic effects associated with atherosclerosis using a comprehensive state-of-the-art whole-body MR examination protocol. The protocol comprises the assessment of the complete arterial vasculature (except coronary arteries), the brain, and the heart.Multi-station whole-body 3D MR angiography was performed in sixty consecutive patients with clinical suspicion for PAOD at 1.5 T (Magnetom Avanto, Siemens, Erlangen, Germany). Functional and delayed enhancement cardiac images were acquired, as well as FLAIR images of the brain and TOF angiography of intracranial vessels. MR and DSA images were assessed by independent observers for atherosclerotic manifestations and other pathology. Sensitivity and specificity for the detection of vascular pathology was calculated for MR data using conventional DSA of the symptomatic region as standard-of-reference.Sensitivity and specificity for the detection of significant vascular stenosis (70 % luminal narrowing) was 94 % and 96 % (PPV 87 %, NPV 98 %). Significant microangiopathic tissue alterations (n = 7) and/or cerebral infarction (n = 18) were diagnosed in 23/60 patients. Thirty-eight of 60 patients presented with systolic left ventricular wall motion abnormalities. In 24 patients subendocardial or transmural delayed enhancement was detected in corresponding regions, indicating prior myocardial infarction.For patients with PAOD and suspected systemic atherosclerotic disease a comprehensive diagnosis of accompanying cardiovascular pathology and therefore staging of systemic atherosclerotic disease is feasible within one MR examination.

The aim of this study was the optimization of a gradient echo (GRE) MR tagging sequence at 3.0 T in comparison to 1.5 T in order to obtain the best image contrast between the myocardium, tag lines and blood signal. Theoretically expected improvements of signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were also calculated.14 healthy volunteers (8 male, 6 female; mean age 43.4 +/- 10.3 years) were scanned using a 3.0 T as well as a 1.5 T whole-body system. A GRE flash-2 D tagging sequence was evaluated (midventricular short axis view) by varying the flip angle (8 - 16 degrees ), slice thickness (4 - 8 mm; fixed flip angle 1.5/3.0 T: 12 degrees /8 degrees , tag size 8 mm) and tag size (4 - 8 mm, fixed flip angle 1.5/3.0 T: 12 degrees /8 degrees , slice thickness 6 mm). The field of view, acquisition time and temporal resolution (45 ms) were kept constant. Qualitative and quantitative image analysis was performed by calculating the SNR, CNR (tag) as well as the relative contrast between the myocardium and tag lines (RCMT).Based on individual comparison, the best imaging protocol was found at a slice thickness of 6 mm, tag size of 8 mm, optimized flip angle of 8 degrees (3.0 T) and 12 degrees (1.5 T), respectively. Compared to 1.5 T, a significantly higher overall image score was determined (mean +/- sd; 3.2 +/- 0.2 vs. 2.7 +/- 0.4) and a strong correlation between the CNR (tag) and RCMT for flip angle alpha and the slice thickness was found. A higher field strength resulted in an 80 % increase in the CNR (tag) compared to 1.5 T (mean 10.7/6.1). Furthermore, the SNR was improved by 35 % (mean 20.6/15.3) and the RCMT by 35 % (mean 0.47/0.35).Myocardial tagging at 3.0 T has shown superior image quality in comparison to 1.5 T due to a higher baseline SNR and an improved CNR as well as RCMT. The suppressed fading of the tags enables the accessibility to the diastolic phase of the cardiac cycle.

The purpose of this study was to determine the volume of the tongue using MRI. The correlation of the individual volume of the tongue and the size of the oral cavity was to be investigated.To analyze the tongue volume we combined coronal and sagittal data acquisition, which divided the tongue virtually into two lateral and one medial part. This procedure helped to decrease artefacts by partial volume effect. In 20 probands (m/f 7/13, average age of 36.3 years) the volume of the tongue was determined. Imaging protocol: Magnetom 63 SP (Siemens, Erlangen), T1-weighted sequences (TR/TE 500 ms/10 ms), slice thickness 5 mm, matrix 256 x 256, FOV 250 mm.There was a significant linear regression between the tongue volume and height of the mouth cavity. This correlation can be used to calculate the normal volume of a patient's tongue.Volumetry of the tongue can be carried out by means of MRI without application of injurious X-rays. It can be employed before as well as after tongue reduction surgeries for therapy control. The individual ideal tongue volume can be determined easily by determination of the height of the oral cavity.

The superficial femoral artery (SFA) is a frequent target of atherosclerotic disease predominantly in the proximal section near the bifurcation to the deep femoral artery and in the distal section where the adductor muscles tend to compress the artery. In the past, SFA revascularization was the domain of vascular surgery (femoropopliteal and femorodistal bypasses). However, with the development of endovascular treatment and advancing techniques as well as more sophisticated stenting material and balloons, endovascular treatment is nowadays not just a treatment option but, in most cases, preferable at least as initial revascularization procedure in the treatment of peripheral artery vascular disease. In the last years, many efforts have been made to fight restenosis in revascularized artery segments after stenting and/or angioplasty. This article aims to give a review on this topic including the most recent experience with the various latest revascularization techniques such as drug eluting stents, coated stent grafts, brachytherapy, cryoplasty, cutting balloons, and drug coated balloons.

Dorsoventral stabilization is a common procedure to treat thoracolumbar spine fractures. Especially in respect of the evaluation of alternative procedures to autogenous bone graft, a standardized evaluation score for ventral spondylodesis is necessary.In a group of 44 patients a follow-up CT scan was evaluated with a standardized scoring system by four different independent evaluators (a trauma surgeon, an orthopedic surgeon, and two radiologists). The score is based on the morphologic classification of the region between graft and vertebral body. It allows a classification of the spondylodesis as sufficient, partial, and not sufficient.The statistical evaluation of the classification of the different evaluators shows very good interobserver agreement in monosegmental fusion and good agreement in bisegmental fusion.The demonstrated score is easy to handle, does not need special equipment for CT scans, and shows good interobserver agreement in the classification of spinal fusion after ventral spondylodesis for thoracolumbar spine fracture.

First results of a study about the efficacy of magnetic resonance-(MR-)guided radiofrequency ablation of renal cell carcinomas (RCC) are presented.Eight patients (63 to 82 years old) with RCC up to 3.9 cm in diameter were treated by percutaneous RF ablation under MR-guidance in an open MR scanner at 0.2T field strength. For positioning of the RF-electrode, fluoroscopic rapid gradient echo sequences (acquisition time about 2 sec) were used. The ablation was monitored by intermittent imaging with T1- and T2-weighted spin echo sequences.In each patient, the applicator was successfully positioned within the tumor using MR-guidance. Seven of eight patients were completely treated within one single session; one patient had to be retreated for tumor relapse at 13 months. The mean number of electrode repositionings under MR guidance for complete ablation was 2.0; ablation time ranged between 12 and 28 minutes. Maximum diameter (volume) of induced coagulation necrosis within one session was 3.9 cm (30.2 cm (3)) by using cluster electrodes. With single electrodes, maximum short axis diameter of coagulation without repositioning was 2.4 cm (11.6 cm (3)). All patients are now disease-free after a mean follow up of 13 months (5 to 21 months). No major complications occurred during or after the ablation procedure.MR-guided RF ablation in an open interventional 0.2T MR-unit is a safe and effective modality for the treatment of RCC. Fast MR-imaging is a convenient method for exact positioning of MR-compatible RF-electrodes. Near on-line MR-monitoring of ablation procedure with T2-weighted imaging allows for immediate assessment of the coagulation extent.

To evaluate graft patency, flow and flow reserve in patients with minimal invasive direct coronary artery bypass (MIDCAB) of internal mammary artery (IMA) grafts using a combined MR protocol with phase-contrast technique and MR angiography.At a 1.5T Magnetom Sonata (SIEMENS), 19 symptomatic (angina CCS I-III, intermittent thoracic discomfort, scar disorders) patients (59.9 +/- 7.9 years old) with 19 left internal mammary artery (LIMA) grafts implanted in minimal invasive technique were examined 6.9 +/- 1.5 years post surgery. Contrast enhanced MR angiography (TR 2.5 ms, TE 1 ms, flip angle 20 (o), spatial resolution 1.4 x 0.9 x 1.0 mm(3), breath hold technique, no ECG-triggering, 25 ml Gd-DTPA) was performed to assess bypass patency. Phase-contrast flow measurements with retrospective gating (TR 41 msec, TE 3.2 msec, flip angle 30 degrees , spatial resolution 1.1 x 1.1 x 5 mm(3), temporal resolution 42 msec, venc 90 cm/sec) were applied in the IMA grafts at rest and after stress induction with dipyridamole (0.56 mg/kg/BW). For comparison, graft patency was evaluated by multidetector-row computed tomography (16-row CT). In 9 patients a selective catheter angiography was performed.MIDCAB grafts were occluded in 4/19 patients. In 4 patients the anastomosis to LAD was highly stenotic (70 %) at MDCT (2 experienced investigators in consensus reading). In MRA 9 grafts could be delineated completely including the distal anastomosis to LAD (47 %). In 9 patients the distal part could not be evaluated. In patients with patent grafts (MDCT), a significant improvement of graft flow (at rest 75.4 +/- 33.3 ml/min; after stress 202.7 +/- 49.6; P0.002) and flow reserve (patent grafts 3.0 +/- 1.1; stenotic grafts 1.5 +/- 0.2, P0.02; occluded grafts 0.9 +/- 0.2, P0.01) after stress induction was detected. Diastolic-to-systolic peak velocity ratios (D/S-PVR) at baseline were not significant between patent and stenotic grafts. Mean flow at baseline and after stress induction and flow reserve show a high sensitivity (91/92 /83 %) and specificity (86 /100/83 %) for detection of graft stenosis. MR angiography combined with flow reserve measurements could distinguish between occluded/stenotic and patent grafts in all MIDCAB grafts.MR imaging allows combined assessment of bypass patency and flow with flow reserve in patients after MIDCAB. The protocol of this study is applicable for the evaluation of graft patency in patients after revascularization.

PURPOSE. This work aims to present a preparation technique for ex-vivo MR examination of SPIO (superparamagnetic iron oxide) containing solutions or SPIO labeled cells. Accumulations of SPIO particles and labeled cells were prepared in different concentrations using agar gel phantoms. Signal extinction around accumulations of magnetic material was examined systematically by gradient echo sequences with variable echo times and spatial resolution. The correlation between local iron concentration and diameter of signal extinction in MR gradient echo images was investigated.Resovist, (SHU 555A) was used as superparamagnetic contrast medium. Different concentrations of SPIO-containing solutions (0.75 - 15 mg Fe/10 ml) and magnetically labeled SK-Mel28 cells (25,000-1,000,000 cells/10 ml) were accommodated inside a defined volume in an agar matrix. Diameters of signal void were assessed in dependence on local iron concentration, echo time (5-25 ms) and isotropic spatial resolution (length of voxel 0.25 - 0.60 mm). Measurements were performed on a clinical MR whole body scanner (3 Tesla) using a spoiled gradient echo sequence (FLASH).For the present experimental conditions sensitivity to detect the magnetic label was maximized using TE 25 ms. In contrast, the area of signal cancellation was minimized using TE 5 ms and isotropic resolution of 0.25 mm. In the latter case the image indicated the area of magnetic material most precisely. Diameter of signal cancellation was a logarithmic function on local iron concentration. In the presented set-up detection of concentrations as low as 0.75 mg Fe/10 ml in SPIO-containing solution or 1.25 mg Fe/10 ml in SPIO-labeled SK-Mel28 cells was certainly possible.The proposed preparation strategy with a well defined spatial distribution of the magnetic material in an agar gel phantom produced reliable results and appears clearly superior compared to set-ups with randomly distributed material in glass tubes. The diameter of the signal extinction in gradient echo images was significantly affected by the choice of echo time and spatial resolution. The calibration of signal cancellation versus iron concentrations may be valuable to assess SPIO concentrations and possibly numbers of labeled cells under specific conditions in vitro or even in vivo.

To evaluate the efficacy and specific properties of MR imaging-guided corticosteroid infiltration of the sacroiliac (SI) joints in the treatment of therapy-refractory sacroiliitis in patients with ankylosing spondylitis.In this study, 26 patients were prospectively included. Inclusion criteria were AS with therapy refractory acute sacroiliitis and inflammatory back painor = 6 months. The intervention was performed using an open low-field MR-scanner. Inflammatory back pain was assessed on a visual analog scale (VAS). Success of the therapy was defined as an absolute reduction of the VAS score/= 5, a relative reduction of the VAS scoreor = 35 % and persisting improvementor = 2 months. The grade of sacroiliitis was documented using high-field MR imaging. Variables were compared using McNemar test and Wilcoxon test. The mean remission time was calculated using a Kaplan-Meier analysis. A p-value0.05 was considered statistically significant.The intervention was technically successfully performed in all patients. Following MR imaging-guided corticosteroid infiltration of the SI joints, the VAS score improved from 8 (5 - 10) points to 4.5 (0 - 8) points (- 44 %) in all patients (n = 26), which was statistically significant (p0.001). Of 26 patients, 22 (85 %) fulfilled the predefined criteria for successful therapy. This group had a statistically significant (p0.01) improvement of the VAS score from 8 (6 - 10) to 3 (0 - 5) (- 63 %). Improvement was seen after 7 (1 - 30) days. There was a marked reduction of the subchondral bone marrow edema (- 38 %). The mean remission time was 12 (4 - 18) months.MR imaging-guided corticosteroid infiltration of the SI joints proved to be an effective therapy of inflammatory back pain in patients with therapy refractory AS. With the ability of multiplanar imaging, precise localization of the bone marrow edema and the lack of ionizing radiation, interventional MR imaging currently represents the superior method for the treatment of the predominantly young patient group presenting with ankylosing spondylitis. Owing to short intervention times, open MR-scanners are ideally suited for MR imaging-guided infiltration of the SI joints.