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Endoscopic retrograde cholangiopancreaticography (ERCP) is the morphologic gold standard for the diagnosis of chronic pancreatitis. Magnetic Resonance Imaging (MRI) enables the visualization of not only the pancreatic duct but also the surrounding parenchyma using T2- and T1-weighted sequences before and after the application of a contrast agent. Moreover, it allows the depiction of ductal segments distal to a stenosis or occlusion. However, conventional Magnetic Resonance Cholangiopancreaticography (MRCP) was not able to achieve accuracy similar to that of ERCP. Despite many technological innovations, such as fast breath-hold acquisitions or respiratory-gated 3D sequences, this drawback could not be overcome. In recent years, secretin-enhanced MRCP has been used for the diagnosis of chronic pancreatitis. A recent study showed that secretin not only improves the visibility of the pancreatic duct and its side branches but it also enhances the diagnostic accuracy of MRCP. The sensitivity, specificity, and positive and negative predictive values were improved by the application of secretin. Moreover, the agreement between independent observers increased after the use of secretin. In addition, quantitative post-processing tools have been developed that enable the measurement of the exocrine pancreatic output non-invasively using secretin-enhanced MRCP. These tools facilitate applications, such as functional follow-up after pancreaticogastrostomy and pancreaticogastric anastomoses, evaluation of the functional status of the graft after pancreas transplantation and follow-up of pancreatic drainage procedures and duct disruption.

Integration of MR venography in a comprehensive MR imaging protocol in patients with suspected pulmonary embolism (PE) and evaluation of contrast media dosage, timing and postprocessing for diagnostic accuracy.Forty-eight consecutive inpatients with suspected PE or deep vein thrombosis were examined by MR venography according to one of the following protocols: protocol I: MR venography only, 0.25 mmol/kg body weight (BW) Gadopentate dimeglumine (Gd-DTPA) as single dose, bolus timing; protocol II: MR angiography of pulmonary arteries with a cumulative dosage of 0.25 mmol/kg contrast media, modification of coil setting for MR venography without further contrast media application; protocol III: as protocol II but with 0.125 mmol/kg BW, followed by MR venography. Signal-to-noise ratio, contrast-to-noise ratio, number of definable vascular segments and image quality were evaluated. The results were compared to conventional bilateral venography.All MR venography examinations were of diagnostic quality and the examination time was below 10 min. MR venography could be performed in all 48 patients compared to 43 of 48 patients for conventional venography. Significantly more superficial and deep veins of the leg could be visualized by MR venography (94 % compared to 83 % for conventional venography). Sensitivity and specificity were 100 % and 92 %, respectively. Quality differed significantly between 0.125 mmol/kg (protocol III) and 0.25 mmol/kg Gd-DTPA (protocols I and II) while timing did not influence quality (protocol I vs. II).An integrated MR diagnostic evaluation of pulmonary arteries and veins of the leg is feasible in patients with suspected PE. MR venography with 0.25 mmol/kg Gd-DTPA reliably depicts the venous system of the leg more completely than conventional venography with at least equivalent diagnostic confidence.

Definition of the prognostic value of clinical and morphological findings in the mid-term follow-up of OCD of the femoral condyle and talus. Demonstration of the consolidation of OCD on MRI depending on different therapies.76 patients were examined before and at an average of 30 months after conservative or surgical therapy using T1 and T2 weighted SE and 3D-FISP sequences and contrast enhanced studies. Six clinical (age, gender, site, duration and severity of symptoms, therapy) and six morphological (size, signal intensity, fragmentation, contrast enhancement, condition of cartilage, staging) data were registered on first MRI and correlated with the degree of consolidation of OCD (partial and complete remission, no change and progression) on control MRI.Patients under 17 years showed partial or complete remissions in 73%, those of 17 years or older in 33%. Conservatively treated patients had a higher remission rate (54%) than those treated with different surgical techniques (drilling 50%, refixation 43%, abrasio 38%). Small OCDs had a higher remission rate than large lesions (63% vs. 33%). OCDs covered with intact cartilage healed better than lesions with chondral defects (61% vs. 26%). Contrast enhancing fragments had a better prognosis than non-enhancing lesions (100% vs. 40%).Prognosis of OCD can be better estimated when size of OCD, condition of cartilage and enhancement of contrast agent is graduated with MRI and patient age is registered. The consequences for therapy planning are great.

An experimental study was performed on joint specimens of the knee to assess the advantages and disadvantages of 14 generally available sequences in cartilage imaging.Each of the 50 surgically exposed cadaveric joints of the knee was examined by the following sequences: T1, proton- and T2 weighted spin echo(SE) sequences, proton- and T2 weighted Turbo-SE, T1 weighted SE with fat suppression, MTC combined with T1-weighted SE and T2 weighted FLASH-2 D, STIR, FISP-3 D, FLASH-3 D (with fat suppression), and MR arthrography. We assessed the image quality by a scale, signal to noise-ratio of cartilage and joint fluid, and the accuracy in detection of cartilage lesions. Pathology and arthroscopy were reference methods to MRI, and demonstrated grade 1-4 lesions on 186 of 300 joint facettes.Advanced stages of cartilage lesions (65 grade 3 and 4 lesions) were detected by standard SE sequences in 67-94%. Application of volume techniques (FISP-3 D, FLASH-3 D), high definition matrix (512 pixel), MTC with FLASH-2 D and MR-arthrography improved the sensitivity up to 82-100%. Superficial lesions (65 grade 2 lesions) were demonstrated in 3-38%, and on MR arthrography in 45%. Structural changes (56 Grade 1 lesions) were recorded on MR) in only 10%.With regard to standard SE sequences, the detectability of cartilage lesions can be improved by techniques that use 512 matrices, selective cartilage imaging, and volume acquisition.