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Purpose To survey integrative teaching in radiology at German universities. Materials and methods A questionnaire about radiological education was sent electronically to all 37 chairpersons of university radiology departments in Germany. The questions included the course type, teaching methods, concept, perception, and advantages and disadvantages of integrative teaching. Statistical analysis was performed with nonparametric statistics and chi-square test. Results The survey was considered representative with a return rate of 68 %. Integrative teaching is established at 4/5 of all departments. Integrative teaching is well accepted with an acceptance rate that is significantly higher in so-called "Modellstudiengangen" [model courses of study] (100 %) compared to conventional courses of study (72 %). The advantages of integrative teaching include linking of content (92 %) and preparation for interdisciplinary work (76 %). The disadvantages include high effort (75 %) and time (67 %) for organization. Furthermore, there is a risk that basic radiological facts and knowledge cannot be conveyed and that the visibility of radiology as an independent discipline is lost. Conventional radiological teaching has a similarly high acceptance (84 %) compared to integrative courses (76 %). Conclusion Integrative teaching has a high acceptance among chairpersons in radiology in Germany despite the greater effort. A good interdisciplinary collaboration is essential for integrative teaching and at the same time this can be conveyed to the students. However, the visibility of radiology as a discipline and the possibility to cover basic radiological content must be ensured. Therefore, both conventional courses and integrative teaching seems reasonable, especially in cross-disciplinary subjects such as radiology. Key points Both integrative teaching and conventional radiological teaching are highly accepted. The advantages include the linking of multidisciplinary content and the preparation for interdisciplinary cooperation. The disadvantages include more time and effort for organization and reduced visibility of cross-disciplinary subjects.

The aim of this study was to investigate frequencies of typical artifacts in low-dose pediatric lung examinations using high-pitch computed tomography (HPCT) compared to MDCT, and to estimate the effective radiation dose (Eeff).Institutional review board approval for this retrospective study was obtained. 35 patients (17 boys, 18 girls; mean age 112 ± 69 months) were included and underwent MDCT and follow-up scan by HPCT or vice versa (mean follow-up time 87 days), using the same tube voltage and current. The total artifact score (0 - 8) was defined as the sum of artifacts arising from movement, breathing or pulsation of the heart or pulmonary vessels (0 - no; 1 - moderate; 2 - severe artifacts). Eeff was estimated according to the European Guidelines on Quality Criteria for Multislice Computed Tomography. The Mann-Whitney U test was used to analyze differences between the patient groups. The Spearman's rank correlation coefficient was used for correlation of ordinal variables.The scan time was significantly lower for HPCT compared to MDCT (0.72 ± 0.13 s vs. 3.65 ± 0.81s; p 0.0001). In 28 of 35 (80 %) HPCT examinations no artifacts were visible, whereas in MDCT artifacts occurred in all examinations. The frequency of pulsation artifacts and breathing artifacts was higher in MDCT compared to HPCT (100 % vs. 17 % and 31 % vs. 6 %). The total artifact score significantly correlated with the patient's age in MDCT (r = - 0.42; p = 0.01), but not in HPCT (r = - 0.32; p = 0.07). The estimated Eeff was significantly lower in HPCT than in MDCT (1.29 ± 0.31 vs. 1.47 ± 0.37 mSv; p 0.0001).Our study indicates that the use of HPCT has advantages for pediatric lung imaging with a reduction of breathing and pulsation artifacts. Moreover, the estimated Eeff was lower. In addition, examinations can be performed without sedation or breath-hold without losing image quality.• Fewer artifacts in pediatric lung imaging with HPCT• Reduced Eeff in HPCT• HPCT without sedation or breath-hold without loss of image quality.

Purpose: Energy transfer from radiofrequency (RF) applicator to tissue is both precondition and limiting factor. The purpose of this ex vivo study was to examine the influence of form of energy delivery on ablation result during RF ablation with cryo-cooled applicators. Materials and Methods: One hundred eight ablations were performed in ex vivo bovine liver under continuous energy delivery (A), pulsed energy delivery with reduced current during ablation pause (B) and impedance-dependent energy delivery. Maximum ablation time was 20 min. Early termination of ablation in case of loss of conductivity. Optimal ablation parameters were assessed. Short axis diameter of the ablation zone and ablation duration were determined. Ablation results under mode A, B and C were compared with analysis of variance and Tukey-Kramer HSD test. Influence of ablation duration on short axis diameter was evaluated with regression analysis. Results: Significantly largest short axis diameter (51.1 mm ± SD 2.3; p = 0.01) was reached with impedance-dependent energy delivery (pulsed: 46.1 mm ± SD 5.6; continuous: 44.4 mm ± SD 4.1). Significantly longest ablation duration (1061.6 s ± SD 42.4; p = 0.01) was reached with impedance-dependent energy delivery (pulsed: 815.7 s ± 41.3; continuous: 715.3 s ± SD 82.2). Linear correlation between ablation duration and short axis diameter was calculated (R = 0.7). Conclusion: Modification of energy delivery during RF ablation with cryo-cooled applicators improves energy transfer to tissue and enables larger ablation zones. Key Points: • Impedance-dependent energy delivery prevents early termination in kryo-based RF-ablation, • Impedance-dependent energy delivery enables larger ablation zones than continuous energy delivery, • Reduced current during ablation pause does not improve ablation results. Citation Format: • Hoffmann R, Bustamante J, Pitsaer C et al. Forms of Energy Delivery during Cryo-cooled Radiofrequency Ablation for Optimization of the Ablation Result. Fortschr Rontgenstr 2014; 186: 945 – 950

Purpose: Sudden cardiac death [SCD] in competitive athletes is caused by a diverse set of cardiovascular diseases such as hypertrophic and dilated cardiomyopathy [HCM/DCM], myocarditis, coronary anomalies or even coronary artery disease. In order to identify potential risk factors responsible for SCD, elite athletes underwent cardiac magnetic resonance [CMR] imaging. Materials and Methods: 73 male [M] and 22 female [F] athletes (mean age 35.2 ± 11.4 years) underwent CMR imaging. ECG-gated breath-hold cine SSFP sequences were used for the evaluation of wall motion abnormalities and myocardial hypertrophy as well as for quantitative analysis (left and right ventricular [LV, RV] end-diastolic and end-systolic volume [EDV, ESV], stroke volume [SV], ejection fraction [EF] and myocardial mass [MM]). Furthermore, left and right atrial sizes were assessed by planimetry and delayed enhancement imaging was performed 10 minutes after the application of contrast agent. Coronary arteries were depicted using free-breathing Flash-3 D MR angiography. Results: The quantitative analyses showed eccentric hypertrophy of the left ventricle (remodeling index [MM/LV-EDV]: M 0.75, F 0.665), enlargement of the RV volumes (RV-EDV: M 122.6 ± 19.0 ml/m², F 99.9 ± 7.2 ml/m²) and an increased SV (LV-SV: M 64.7 ± 10.0 ml/m², F 56.5 ± 5.7 ml/m²; RV-SV; M 66.7 ± 10.4 ml/m², F 54.2 ± 7.1 ml/m²). Abnormal findings were detected in 6 athletes (6.3 %) including one benign variant of coronary anomaly and abnormal late gadolinium enhancement in 2 cases. None of the athletes showed wall motion abnormalities or signs of myocardial ischemia. Conclusion: CMR imaging of endurance athletes revealed abnormal findings in more than 5 % of the athletes. However, the prognostic significance remains unclear. Thus, cardiac MRI cannot be recommended as a routine examination in the care of athletes. Key points: Citation Format

Purpose: Comparison of dose area products (DAP) in diagnostic angiography procedures between an image intensifier (II) and a flat panel detector (FPD) angiography system and the evaluation of DAP/body mass index (BMI) dependency. Materials and Methods: An image intensifier system or a flat panel detector system was used to perform 571 diagnostic angiographies (n = 328 and n = 243, respectively) of 5 different types: peripheral arterial, venous, single leg, abdominal and upper extremity. The results were retrospectively analyzed. The DAP, fluoroscopy time (t) and the number of series of the respective interventions as calculated by the respective machines was compared for all interventions and for the respective subtypes and machines. The BMI dependency was calculated separately for both machines for all interventions by subdividing the patients into 6 BMI classes defined by the WHO. Results: The average DAP for all diagnostic interventions was 1958.9 cGy×cm 2 (t = 384.6 s, n = 7.85 series) for the II and 2927.4 cGy×cm 2 (t = 267.4 s, n = 7.02 series) for the FPD. Group-dependent differences ranged between + 21 and + 252 % when using the FPD system. After time standardization, the respective increases were found to be 120 % for the FPD system. The DAPs increased considerably in patients with higher BMIs (766.7 cGy × cm 2 – 6892.6 cGy × cm 2 , II machine, 950.5 cGy × cm 2 – 12 487.7 cGy × cm 2 , FPD machine) with a greater DAP gain seen for the FPD. The average duration of the interventions was higher using the II machine. Conclusion: The use of an FPD system led to higher DAP values compared to the II system in diagnostic angiographic procedures. In addition, increased BMI values led to higher DAPs, especially for the FPD machine. However, the average fluoroscopy times were shorter.

Endovascular aneurysm repair (EVAR) can be challenging in angulated access vessels. The aim of this study was to evaluate a new wire technique for installing a buddy wire in the event of failure of simple advancing of a super stiff guide.We investigated 8 patients eligible for EVAR. All patients presented with heavily kinked pelvic access and failure of primary advancing of a stiff guide wire through a placed catheter. A double wire technique with a combination of soft and stiff wires was applied to place a super stiff buddy wire. Cumulative angulation quantified by the sum of angles of the tortuous pelvic access vessels was measured in pre- and post-interventional CT as well as in angiographic studies of the EVAR procedure. Patients were followed up on by CT in the first 6 months.A buddy wire could be installed in all patients (100%) with significant straightening of the access vessel from a median cumulative angulation of 252.4±38.1° before intervention to 159.4±44.6° after placement of the buddy wire (p0.001). There was no technical failure of device passage and all stent-grafts could be deployed safely. Three cases of stenosis caused by torsion distal to the aortic stent-graft were seen after stent-graft delivery. One case of stenosis was hemodynamically relevant and was successfully stented. No major adverse events occurred within the first 6 months of follow-up. The new step-by-step wire technique is feasible and safe in the case of hostile pelvic vessel access, and facilitates the advancement of aortic stent-grafts in off-label patients.

Ziel: Evaluierung der CT-gesteuerten Radiofrequenz(RF)-Ablation von Osteoidosteomen bei unselektierten Patienten mittels intern-gekuhlten monopolaren RF-Einzelsonden hinsichtlich technischem Erfolg, Komplikationen und unter besonderer Berucksichtigung des klinischen Langzeiterfolgs. Material und Methoden: Zwischen April 1999 bis Juli 2009 wurde bei n = 23 Patienten unter Vollnarkose eine CT-gesteuerte RF-Ablation durchgefuhrt mittels intern-gekuhlten Einzelsonden (Cool-tip, Valleylab, TycoHealthcare, Boulder, USA/aktive Elektrodenlange: 10 mm). Der Nidus wurde entweder durch manuelle oder maschinelle Bohrung mit einem koaxialen System (Bonopty, Radi Medical System, Schweden und Handakku-Bohrer, Fa. Hager/Meisinger, Deutschland) erreicht. Der technische Erfolg wurde anhand einer CT-Kontrolle (Mehrzeilenspiral-CT, Siemens Medical Solutions, Forchheim) wahrend der RF-Ablation uberpruft. Der klinische Langzeiterfolg wurde durch Patientenbefragung ermittelt vor Entlassung sowie in Verlaufskontrollen nach 6, 12 und 18 Monaten. Nach 18 Monaten erfolgte jahrlich eine mundliche Befragung der Patienten. Ergebnisse: Der technische Erfolg lag bei 100 %. Der Nidus war in n = 19 der Falle an der unteren Extremitat (Femur n = 11; Tibia n = 7, OSG n = 1) und in n = 4 der Falle an der oberen Extremitat (Humerus n = 1, Ellenbogen n = 2, Radius n = 1) lokalisiert. Minor-Komplikationen (n = 2) wurden bei maschineller Bohrung beobachtet (jeweils Abbruch der Bohrerspitze). Die Hospitalisation betrug durchschnittlich 1,5 Tage (1-2 Tage). Wahrend einer durchschnittlichen Verlaufskontrolle von 75,9 (18-120) Monaten waren alle Patienten ohne Lokalrezidiv. Ein Patient hatte eine Woche nach der Behandlung erneut vorubergehend Schmerzen ohne Rezidivnachweis. Schlussfolgerung: Die CT-gesteuerte RF-Ablation mittels intern-gekuhlten monopolaren RF-Einzelsonden ist eine effektive und sichere minimalinvasive Methode zur Behandlung von Osteoidosteomen mit einem exzellenten klinischen Langzeiterfolg.

PURPOSE: This study investigates the features of neutropenic enterocolitis (NE) in adults. MATERIALS AND METHODS: Chart and radiology report reviews were used to identify neutropenic patients with hematological diseases undergoing chemotherapy, who had CT scans for the clarification of abdominal symptoms between October 2003 and October 2009. Patients with any cause for enteritis other than NE were excluded. The scans were analyzed with respect to imaging features and location. Morphological findings were correlated with clinical data. RESULTS: Thirty-one patients with NE (median age 46 years; range 20 – 75) could be identified. Wall thickening and hyperemia could be found in all bowel segments from jejunum to rectum. The right hemicolon was the most frequent location in 19 patients (61 %). Involvement was generalized in 6 patients (19 %) and segmental in 25 cases (81 %). The longer the duration of neutropenia, the more likely generalized involvement of the bowel was. In 8 patients who underwent CT follow-up, the appearance of bowel segments had completely (n = 5) or partially (n = 3) returned to normal at the latest 14 days after the initial diagnosis. Eight patients (26 %) died 1 – 78 days after NE, 7 of who had previously recovered from NE. CONCLUSION: CT findings are useful for the diagnosis of NE and should be considered even in the presence of isolated small bowel involvement. The terms NE and typhlitis should thus no longer be used synonymously.

PURPOSE: 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. MATERIALS AND METHODS: 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. RESULTS: 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 (p 0.05). All cases with CR MRT had wash out or plateau shape of the SI time curve before NT and showed continuous enhancement thereafter. CONCLUSION: 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.

PURPOSE: To determine whether lesion scoring allows valid BI-RADS ® classification and prediction of malignancy of breast lesions detectable solely with MRI. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

PURPOSE: 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). MATERIALS UND METHODS: 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. RESULTS: 9 lesions were malignant (31 %). All but one lesion (96 %) were able to be localized exactly with a clip-lesion distance of ≤ 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). CONCLUSION: 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.

Ziel: Die Darstellbarkeit oropharyngealer Leitstrukturen ist durch Metallartefakte von Zahnimplantaten eingeschrankt. Ziel der Studie war der Vergleich der Bildqualitat von multiplanaren Rekonstruktionen (MPR) mit einer zusatzlichen angulierten Spirale in der Halsbildgebung mittels Dual-Source-CT. Material und Methoden: Bei 62 Patienten wurde eine Halsbildgebung mittels DSCT durchgefuhrt. MPRs des axialen Datensatzes sowie eine zusatzliche angulierte Spirale parallel zum Mundboden wurden akquiriert. Anschliesend wurden anatomische Leitstrukturen bezuglich ihrer Uberlagerung durch Metallartefakte anhand einer Visualskala von 1 (keine Artefakte) bis 4 (starke Artefakte) analysiert. Ergebnisse: Wahrend 87,1 % der anatomischen Strukturen in den MPRs starke Artefakte (3,12 ± 0,86) aufwiesen, zeigten die Leitstrukturen in der angulierten Spirale lediglich geringfugige Artefakte (1,28 ± 0,46). Der diagnostische Zugewinn durch die angulierte Spirale bezuglich des Schweregrads der Artefakte war signifikant (p < 0,01). Schlussfolgerung: MPRs sind nicht geeignet, um Zahnartefakte ausreichend zu reduzieren. Eine zusatzliche angulierte Spirale ist bei Patienten mit Zahnartefakten, die die anatomischen Leitstrukturen des Oropharynx uberlagern, empfehlenswert und sollte in der taglichen Routine eingesetzt werden. Als Folge des statischen Gantryaufbaus des DSCT ist der Einsatz einer flexiblen Kopfschale zur Akquisition einer angulierten Spirale notwendig. Purpose: Important oropharyngeal structures can be superimposed by metallic artifacts due to dental implants. The aim of this study was to compare the image quality of multiplanar reconstructions and an angulated spiral in dual-source computed tomography (DSCT) of the neck. Materials and Methods: Sixty-two patients were included for neck imaging with DSCT. MPRs from an axial dataset and an additional short spiral parallel to the mouth floor were acquired. Leading anatomical structures were then evaluated with respect to the extent to which they were affected by dental artifacts using a visual scale, ranging from 1 (least artifacts) to 4 (most artifacts). Results: In MPR, 87.1 % of anatomical structures had significant artifacts (3.12 ± 0.86), while in angulated slices leading anatomical structures of the oropharynx showed negligible artifacts (1.28 ± 0.46). The diagnostic growth due to primarily angulated slices concerning artifact severity was significant (p < 0.01). Conclusion: MPRs are not capable of reducing dental artifacts sufficiently. In patients with dental artifacts overlying the anatomical structures of the oropharynx, an additional short angulated spiral parallel to the floor of the mouth is recommended and should be applied for daily routine. As a result of the static gantry design of DSCT, the use of a flexible head holder is essential.

Purpose 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. Materials and methods 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. Results 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. Conclusion 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.

Purpose 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. Materials and methods 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. Results 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. Conclusion 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.

Ziel: Charakterisierung des Erscheinungsbildes der chronisch abakteriellen Prostatitis beim chronisch pelvinem Schmerzsyndrom (CPPS) in der MRT mit spektroskopischer Analyse. Material und Methoden: 18 Patienten im Alter zwischen 25 und 67 Jahren (mittleres Alter 46,2 Jahre, PSA kleiner 5 ng/ml, negativer endorektaler digitaler Tastbefund) mit einem unklaren pelvinen rekurrierendem Schmerzsyndrom uber mindestens 3 Monate wurden klinisch nach den Leitlinien der Urologie fur das CPP Syndrom untersucht. Es erfolgte eine retrospektive Analyse von 30 Prostata 1,5 T-MRT-Untersuchungen mit i. v. Kontrastmittel und endorektaler Spule (28 / 30 Untersuchungen). Es erfolgte eine bildmorphologische Charakterisierung der entzundlich verdachtigen Veranderungen sowie eine semiquantitative T 2w-Signalintensitatswertanalyse (SI Analyse) der peripheren, zentralen und entzundlich verdachtigen Areale sowie des Muskelsignals einschlieslich einer Spektroskopie (9 / 18 Patienten). Zusatzlich eine SI Ratioanalyse der verdachtig entzundlichen und der unauffalligen peripheren Areale zum Muskel. Ergebnisse: Es konnten typische bildmorphologische Stigmata beim CPP Syndrom aufgezeigt werden als T 2w-hypointense, streifige, radiare (n = 12, 66,6 %), kontrastmittelaffine, nichtnodulare Veranderungen ohne Kapselunscharfe und ohne perikapsulare Begleitreaktion. 6 Patienten (33,3 %) zeigten flachenhafte, dreiecksformige Signalabsenkungen. Ein periurethrales Enhancement bestand in 16,6 % der Falle. Die T 2w-SI-Werte und die auf das Muskelgewebe normierte SI Ratio der verdachtig entzundlichen Areale waren im Vergleich zur unauffalligen peripheren Zone deutlich erniedrigt (277,29 STD 77,5 zu 432,9 STD 112,02 respektive 4,94 STD 1,47 zu 7,58 STD 2,01). Spektroskopisch zeigten 3 Patienten ein unauffalliges Cholin+Creatin/Citrat SI Verhaltnis (SI 0,7 und 0.7 and < 3.0). Conclusions: 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.

PURPOSE Evaluation of MR standard imaging and short time inversion recovery (STIR) imaging to assess changes in red bone marrow cellularity after high-dose chemotherapy (HDC) and peripheral blood stem cells transplantation (PBSCT). MATERIALS AND METHODS Sixty-one magnetic resonance (MR) studies were performed in 15 patients (8 female and 7 male, average age 45 years) who received HDC and PBSCT for therapy of either a solid tumor or multiple myeloma. All patients underwent MR examinations of the lumbar region and both femora with T1- and T2-weighted turbo spin-echo (TSE) and STIR sequences at predefined time intervals. Qualitative analysis of the signal intensity was performed by consensus reading of four radiologists. MR results were correlated with results of blood smears and marrow histology. RESULTS STIR sequences demonstrated marked changes in signal intensity not only until the aplasia occurred but also during bone marrow repopulation. An increased signal intensity was observed after HDC in 13/15 patients (87%), followed by a decrease in signal intensity immediately after aplasia in 14/15 patients (93%). Signal intensity further changed parallel to marrow engraftment in 11/15 patients (73%). T2-TSE only showed clear changes during repopulation in 8/15 patients (53%). The individual course of the signal in T1-TSE was markedly inhomogeneous. CONCLUSIONS STIR sequences show bone marrow edema during aplasia and marrow cellularity during reconstitution and are suitable for characterisation of red bone marrow after HDC and autologous PBSCT.

PURPOSE: To analyse the diagnostic accuracy of computed tomography (CT) in ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: 23 patients on mechanical ventilation with a new pulmonary abnormality on chest X-ray were examined with both spiral-CT and high-resolution CT. The diagnosis VAP was made according to prospectively defined criteria. Bronchoscopic specimen asservation with protected specimen brushing (PSB) served as gold standard. RESULTS: With PSB, 11 of 23 patients were found to have VAP. CT showed a sensitivity and specificity of 53% and 63%, respectively. Ground glass infiltrates appeared to have a 100% specificity but were found in only 5/11 patients. CONCLUSIONS: CT is not the method of choice for diagnosing VAP. Ground glass infiltrates seeming to be highly specific are only inconstantly found.

PURPOSE To assess renal artery stenosis (RAS) by 3D phase contrast (PC) MR angiography and dynamic perfusion imaging of the kidneys. METHODS On a standard 1.0 T MR imaging system (Magnetom Expert, Siemens), 32 patients with angiographically proven unilateral RAS were examined using a 3D PC sequence (TR 40 ms/TE 9 ms/venc 30 cm/s). An ECG-gated Turbo-FLASH 2D sequence (TR 4.5 ms/TE 2.2 ms/TIeff. 400 ms) was applied to study the first pass of paramagnetic contrast agent (0.1 mmol Gd-DTPA/kg) through the kidneys. Signal intensity (SI) over time curves of the renal cortex were obtained and evaluated considering temporal relation and percentage of maximum SI compared to the aorta and normal kidneys. Analysis of the MRA was performed by two independent blinded readers. The gold-standard DSA was interpreted by consensus reading of two experienced radiologists. RESULTS RAS was detected by 3D PC MRA with a sensitivity of 93% and specificity of 81% (ppv 82%, npv 93%, accuracy 87%, kappa = 0.61). Maximum SI in RAS was significantly decreased (p 75% (p 0.1). CONCLUSIONS 3D PC MRA is capable of detecting RAS in a high percentage of patients. Dynamic perfusion imaging of the kidneys, applied additionally, can confirm the diagnosis and give valuable information about the hemodynamic relevance of RAS in suspected unilateral disease.

PURPOSE To prove the accuracy of MR methods in the determination of left ventricular (LV) functional parameters and anatomy. MATERIALS AND METHODS At 1.5 T, 20 healthy volunteers and 22 patients with aortic valvular disease (stenosis n = 15, regurgitation n = 7) were examined. Functional parameters like cardiac output, ejection fraction, end-diastolic volume, aortic flow maximum, and time interval from the R-wave to maximum flow were obtained using a velocity encoding 2D FLASH sequence (TR 24 ms, TE 5 ms, venc 250 cm/sec) and segmented breath-hold cine FLASH 2D technique (TR 100 ms, TE 4.8 ms, flip angle 25 degrees, temporal resolution 50 ms). Invasive measurements (Fick principle) served as gold standard, intra- and interobserver variability were determined. RESULTS Differences of functional parameters between normal volunteers and patients were detectable at a high level of significance (p < 0.0001). For cardiac output a superior correlation with the gold standard was found using flow measurements (r = 0.66, p < 0.0007) compared to volumetric calculations from cine studies (r = 0.47, p < 0.02). Interobserver variability was 2.5 +/- 2.7%/4.5 +/- 6.9% (flow quantification/calculations from cine studies), intraobserver variability was 1.7 +/- 1.6%/3.3 +/- 2.2%. CONCLUSIONS MRI is an appropriate tool for determining LV functional parameters and anatomy. Differences between normal volunteers and patients with aortic valvular disease can be detected reliably. Flow measurements turned out to be more accurate than calculations from cine images. Therefore, flow quantification techniques should be preferred for clinical use.

PURPOSE: 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. MATERIALS AND METHODS: 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 of > 70 % was regarded as hemodynamically significant. RESULTS: In MPMRI 37 patients (73 %) showed a stress induced perfusion deficit. In 35 of these patients coronary angiography revealed a stenosis of > 70 %. A total of 38 patients (75 %) showed stenoses of > 70 %. 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). CONCLUSION: MPMRI is a suitable non-invasive method for detecting flow-limiting coronary artery stenoses in patients with a history of stent implantation.

PURPOSE 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. MATERIALS AND METHODS 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. RESULTS 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). CONCLUSION 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.

Ziel: Durch innovative Neuerungen im Bereich der Schichtbildverfahren gewinnt die Ganzkörperbildgebung, insbesondere zur Diagnostik systemischer Tumorerkrankungen, zunehmend an Bedeutung für die klinische Radiologie. Die erhebliche Zahl zu beurteilender Bilder bei zunehmender Arbeitsverdichtung stellt ein wachsendes Problem für den Radiologen dar. Ziel der Arbeit war die Entwicklung und Evaluierung eines Computer-unterstützten Befundungstools, das den Ablauf der Befunderstellung von Ganzkörper-MRT-Datensätzen automatisiert unterstützt. Material und Methoden: Es wurden 13 Ganzkörper-MRT-Datensätze von Patienten mit malignem Melanom sowohl mit konventioneller als auch mit workflowoptimierter Befundungssoftware im Rahmen einer Multireader-Analyse befundet. Zur quantitativen Auswertung wurden von den 3 geblindeten Readern jeweils die Zeiten zum Laden des Datensatzes, die Dauer der Auswertung einer Körperregion (jeweils Kopf, Hals, Thorax, Abdomen und Becken/Skelettsystem) sowie die Dauer zum Wiederauffinden eines vorbeschriebenen Befundes verglichen. Zusätzlich wurde ein Student-t-Test ausgeführt. Für die qualitative Auswertung wurden jeweils der Komfort beim Laden, die Hilfe beim Finden von Läsionen und der Bedienkomfort getrennt bewertet und der Kappa-Wert auf einer Skala von 0 - 4 (0 = schlecht, 4 = sehr gut) berechnet. Ergebnisse: Die Ladezeiten der Untersuchungen betrugen bei dem konventionellen Befundungssystem 39,7 s (± 5,5) und bei dem workflowoptimierten 6,5 s (± 1,4) (p < 0,01), dies entspricht einer durchschnittlichen Verkürzung der Ladezeiten um 83,6 %. In der Kopfregion konnte mittels Befundnavigator die Befundungszeit (konventionell/workflowoptimiert) bei Reader 1/2/3 um 35,9 % (p < 0,01)/49,9 % (p < 0,01)/54,3 % (p < 0,01), in der Halsregion um 48,5 % (p < 0,01)/ 52,6 % (p < 0,01)/59,4 % (p < 0,05), in der Thoraxregion um 59,1 % (p < 0,01)/56,2 % (p < 0,05)/62,1 % (p < 0,05), in der Abdomenregion um 61,9 % (p < 0,01)/62,7 % (p < 0,05)/47,9 % (p < 0,01) und in der Beckenregion um 73,1 % (p < 0,01)/63,7 % (p < 0,05)/ 55 % (p < 0,01) verkürzt werden. Zum Wiederauffinden eines vorbeschriebenen Befundes wurden 148,2 s (± 94,8) gegenüber 2,5 s (± 0,5) benötigt (p < 0,01). Mit und ohne Befundnavigator wurde dieselbe Anzahl an Metastasen gefunden (p < 0,01, k > 0,9). Die qualitative Analyse zeigte in allen Kategorien einen signifikanten Komfortgewinn (p < 0,01, k > 0,9). Schlussfolgerung: Durch den Einsatz der entwickelten Befundungssoftware kann eine signifikante Zeitersparnis bei der Befundung von Ganzkörper-MRT-Datensätzen bei gleichbleibender Befundungsqualität und signifikantem Komfortgewinn erzielt werden. Durch diese Workflowoptimierung erscheint eine breitere klinische Anwendung von Ganzkörperuntersuchungen hinsichtlich der Befundung sowie Befunddemonstration möglich zu werden.