Henning Bovenschulte

Significant improvement of right ventricular function by imatinib mesylate in scleroderma-associated pulmonary arterial hypertension

Sirs: Pulmonary arterial hypertension (PAH) is a devastating disease that harbours a poor prognosis, particularly in patients with scleroderma-associated PAH. Although modern therapies such as endothelin receptor antagonists (ERA), phosphodiesterase type-5 inhibitors (PDE5i) and prostanoids have improved the clinical situation and outcome of affected patients [5], the current medical treatment of PAH is not satisfactory. Recent experimental data suggest that platelet-derived growth factor (PDGF) plays a pivotal role in the pathobiology of PAH by initiating and maintaining the underlying pulmonary vascular remodelling [9]. Consistently, inhibition of PDGF receptor (PDGFR) signalling by the tyrosine kinase inhibitor imatinib mesylate was recently shown to reverse PAH in animal models and to improve the clinical situation in selected patients [3, 7, 9, 10]. However, imatinib was also shown to exert significant cardiotoxicity in animals and humans through its inhibitory effect on the non-receptor Abelson tyrosine kinase (c-Abl) [4]. Further analyses of clinical studies revealed that congestive heart failure is a rare event in patients receiving imatinib therapy, but occurs more frequently in patients with pre-existing cardiac conditions [1]. The latter fact may be of particular significance in patients with PAH and impaired right ventricular function since the right ventricle responds particularly sensitive to hemodynamic and/or cardiotoxic impairment. In addition, patients with scleroderma-associated PAH harbour a lower right ventricular contractility as compared to those with idiopathic PAH [6].

Feasibility of peripheral contrast-enhanced magnetic resonance angiography at 3.0 Tesla with a hybrid technique: comparison with digital subtraction angiography.

Purpose:To prospectively determine feasibility and diagnostic accuracy of 3D contrast-enhanced MR-angiography (CE-MRA) at 3.0 tesla (T) in patients with peripheral arterial occlusive disease. Digital subtraction angiography (DSA) was used as reference standard. Material and Methods:Thirty consecutive patients with suspected peripheral arterial occlusive disease were examined on a 3.0 T MR system by using the integrated whole body coil. A 4-station examination protocol in hybrid technique was chosen, containing 2 gadodiamide injections, the first one for imaging the calf and foot arteries (single-step technique) and the second injection for the visualization of the aortoiliacal and femoral arteries (bolus-chase MRA). All patients underwent DSA within the following 48 hours. The arterial tree of each leg was divided in 15 segments and 4 anatomic regions (iliacal, femoral, popliteal/proximal calf, distal calf/foot). Two radiologists analyzed the MR-images with regard to image quality, grade of stenosis, and venous overlap. DSA-images were analyzed by 2 radiologists in consensus with regard to the stenosis grade. Results:Eight hundred eighty-five and 884 of 889 arterial segments at CE-MRA were rated with excellent or good diagnostic image quality by observer 1 and observer 2, respectively. In only 3 segments image quality was affected by venous contamination. Sensitivity of CE-MRA for determination of relevant arterial stenoses (50%–99%) and occlusions—as compared with DSA—was 95.3% (both observer) and specificity was 98.5% and 97.8% for observer 1 and observer 2, respectively. Conclusion:Peripheral hybrid CE-MRA at 3.0 T is feasible and proved to be reliable at depiction of stenoses and occlusions of the whole pelvic and lower leg arterial system.

Hybrid contrast-enhanced MR angiography of pelvic and lower extremity vasculature at 3.0 T: Initial experience

PURPOSE The objective of this study was to describe contrast-enhanced magnetic resonance angiography (MRA) of the lower extremities at 3.0 T system for assessment of high resolution images in patients with peripheral arterial occlusive disease (PAOD). MATERIAL AND METHODS 21 Patients with suspected PAOD were examined with four-station MRA at a 3.0 T MR system. The MRA protocol consisted of a hybrid technique with two contrast media injections, the first one for visualization of the calf and foot vasculature (non-moving-table technique), the second one for imaging the aortoiliacal and femoral arteries (moving-table technique). For the femoropopliteal and calf station a randomly segmented central k-space ordering (contrast-enhanced timing-robust angiography [CENTRA]) was used. MR-images were analyzed independently by two radiologists with regard to image quality, venous overlap and grade of stenosis. In 6 patients digital subtraction angiography was performed within the following 7 days and evaluated by two radiologists in consensus with regard to the grade of stenosis. The vasculature-tree of each leg was divided in 12 segments, and 3 anatomical regions (iliacal, femoropopliteal, calf/foot). RESULTS 490 and 488 of 495 arterial segments were visualized with diagnostic image quality by observer 1 and observer 2, respectively. Image quality was excellent in 470 and 457 arterial segments, respectively. Only 4 segments were rendered as non-diagnostic due to venous overlap. Relevant arterial stenoses (50-99%) were detected in 43 and 47 segments by observer 1 and observer 2, 66 and 65 arterial segments, respectively, were interpreted as occluded. CONCLUSION The hybrid MRA protocol at 3.0 T offers high diagnostic quality for the whole peripheral arterial tree without venous contamination at high spatial resolution.

Noninvasive in vivo tracking of mesenchymal stem cells and evaluation of cell therapeutic effects in a murine model using a clinical 3.0 T MRI

Cardiac cell therapy with mesenchymal stem cells (MSCs) represents a promising treatment approach for endstage heart failure. However, little is known about the underlying mechanisms and the fate of the transplanted cells. The objective of the presented work is to determine the feasibility of magnetic resonance imaging (MRI) and in vivo monitoring after transplantation into infarcted mouse hearts using a clinical 3.0 T MRI device. The labeling procedure of bone marrow-derived MSCs with micron-sized paramagnetic iron oxide particles (MPIOs) did not affect the viability of the cells and their cell type-defining properties when compared to unlabeled cells. Using a clinical 3.0 T MRI scanner equipped with a dedicated small animal solenoid coil, 105 labeled MSCs could be detected and localized in the mouse hearts for up to 4 weeks after intramyocardial transplantation. Weekly ECG-gated scans using T1-weighted sequences were performed, and left ventricular function was assessed. Histological analysis of hearts confirmed the survival of labeled MSCs in the target area up to 4 weeks after transplantation. In conclusion, in vivo tracking of labeled MSCs using a clinical 3.0 T MRI scanner is feasible. In combination with assessment of heart function, this technology allows the monitoring of the therapeutic efficacy of regenerative therapies in a small animal model.

Complete Remission in a Colon Cancer Patient with a Large, Irresectable Liver Metastasis after XELOX/Cetuximab/Bevacizumab Treatment

Background: Stage IV colorectal cancer is usually an incurable disease. However, patients with resectable metastases have 5-year disease-free survival rates of up to 30%. Even with primarily irresectable disease, cure can be achieved in patients who become operable after neoadjuvant treatment. To improve the prognosis of these patients, highly effective neoadjuvant regimens need to be developed. Case Report: Here, we report the case of a 62-year-old male patient who had been diagnosed with International Union against Cancer (UICC) stage III colon cancer 7 years previously and now presented with a large, irresectable liver metastasis and enlarged perihepatic lymph nodes. After neoadjuvant treatment with cetuximab, bevacizumab and XELOX, the patient showed a complete remission and underwent surgery. Histopathologically, the resected tissue and lymph nodes were free of residual tumor. Conclusion: To our knowledge, this is the first report of a complete pathological response in a patient with irresectable colorectal cancer after intensive chemotherapy/anti-EGFR/ VEGF antibody therapy. This combination regimen may help to improve the survival rates for patients with irresectable disease.

CT coronary angiography: Coronary CT-flow quantification supplements morphological stenosis analysis

BACKGROUND Our rationale was to evaluate whether a 64-slice CT scanner allows accurate measurement of computed tomographic (CT) changes in coronary artery flow profiles and whether CT flow measurements are suitable for classifying the significance and hemodynamic relevance of a stenosis and thereby supplement as a functional parameter for morphological stenosis analysis. METHODS A total of 50 patients prospectively underwent computed tomography coronary angiography (coronary CTA) in a multidetector CT scanner (Brilliance 64, Philips)±1 day before or after invasive coronary angiography (ICA). Immediately thereafter, 2 radiologists reviewed the imaging data to detect any vessel segments with morphology poorly evaluable by coronary CTA. A locally constant cyclical measurement was acquired in these coronary arteries in breath-hold technique during the passage of a 50ml bolus of contrast media. For analysis, time-density curves of the bolus passage were registered in the coronary artery and the aorta (internal reference), the up-slopes were determined and correlated with each other. The results were compared with the ICA findings. RESULTS 47 of 50 CT flow measurements were evaluable. A good correlation was found between the degrees of stenosis and slope ratios in aorta and coronary artery (R(2)=0.92). The threshold corridor was 0.55-0.77 for distinguishing hemodynamically (≥70%) from non-hemodynamically relevant stenoses. CONCLUSIONS CT-based coronary artery flow measurements (CTFM) correlate well with the angiographically determined degree of stenosis and can elevate by non-invasive means the diagnostic accuracy of coronary CTA. From both a clinically diagnostic and scientific standpoint, CTFM proves a suitable method for quantifying coronary blood flow.

Bronchogenic cyst mimicking ischemic heart disease.

Bronchogenic cysts are generally asymptomatic and are detected incidentally by radiographic imaging as a smooth homogeneous mediastinal/pulmonary lesion. We present a case of a large bronchogenic cyst in the posterior mediastinum mimicking ischemic heart disease in a 70-year-old man with unknown heart disease. In patients with chest pain the rare case of a bronchogenic cyst has to be considered for management of atypical angina pectoris.

Image Quality of Digital Direct Flat-Panel Mammography Versus an Indirect Small-Field CCD Technique Using a High-Contrast Phantom

Objective. To compare the detection of microcalcifications on mammograms of an anthropomorphic breast phantom acquired by a direct digital flat-panel detector mammography system (FPM) versus a stereotactic breast biopsy system utilizing CCD (charge-coupled device) technology with either a 1024 or 512 acquisition matrix (1024 CCD and 512 CCD). Materials and Methods. Randomly distributed silica beads (diameter 100–1400 μm) and anthropomorphic scatter bodies were applied to 48 transparent films. The test specimens were radiographed on a direct digital FPM and by the indirect 1024 CCD and 512 CCD techniques. Four radiologists rated the monitor-displayed images independently of each other in random order. Results. The rate of correct positive readings for the “number of detectable microcalcifications” for silica beads of 100–199 μm in diameter was 54.2%, 50.0% and 45.8% by FPM, 1024 CCD and 512 CCD, respectively. The inter-rater variability was most pronounced for silica beads of 100–199 μm in diameter. The greatest agreement with the gold standard was observed for beads >400 μm in diameter across all methods. Conclusion. Stereotactic spot images taken by 1024 matrix CCD technique are diagnostically equivalent to direct digital flat-panel mammograms for visualizing simulated microcalcifications >400 μm in diameter.

[Nausea, diarrhea and paraumbilical flow murmur after ileum resection. Arteriovenous fistula of the superior mesenteric artery].

Der 74-jahrige Patient wurde wegen Ubelkeit, Erbrechen und schon seit Jahren intermittierenden progredienten Diarrhoen vorstellig. Aufgrund eines Non-Hodgkin-Lymphoms mit Dunndarmbefall war bei dem Patienten vor 10 Jahren eine Dunndarmresektion vorgenommen worden. Bei der korperlichen Untersuchung fiel insbesondere ein links paraumbilikales pulssynchrones Stromungsgerausch auf, sodass die Indikation fur ein Angio-CT-Abdomen gestellt wurde. DIE ANGIO-CT ERBRACHTE ZWEI BEFUNDE.WELCHE SIND DAS?ERLAUBEN DIESE BEFUNDE EINE DIAGNOSE? WENN JA, WELCHE?SIND DIFFERENZIALDIAGNOSEN MoGLICH? WENN JA, WELCHE?Auflosung

Internal Impingement of the Shoulder: A Risk of False Positive Test Outcomes in External Impingement Tests?

Background External impingement tests are considered as being particularly reliable for identifying subacromial and coracoid shoulder impingement mechanisms. The purpose of the present study was to evaluate if these tests are likely to provoke an internal shoulder impingement mechanism which, in cases of a pathologic condition, can lead to a positive test result. Method In 37 subjects, the mechanical contact between the glenoid rim and the rotator cuff (RC) was measured quantitatively and qualitatively in external impingement test positions using an open MRI system. Results Mechanical contact of the supraspinatus with the posterosuperior glenoid was present in 30 subjects in the Neer test. In the Hawkins test, the subscapularis was in contact with the anterosuperior glenoid in 33 subjects and the supraspinatus in 18. In the horizontal impingement test, anterosuperior contact of the supraspinatus with the glenoid was identified in 35 subjects. Conclusion The Neer, Hawkins, and horizontal impingement tests are likely to provoke the mechanism of an internal shoulder impingement. A posterosuperior internal impingement mechanism is being provoked predominately in the Neer test. The Hawkins test narrows the distance between the insertions of the subscapularis and supraspinatus and the anterosuperior labrum, which leads to an anterosuperior impingement mechanism.