European radiology
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To evaluate the time course of reversed remodeling after pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension(CTPEH), we studied 22 patients (age: 60 +/- 13 years) with MRI immediately before, 1 month, 3 months, and 6 months after PEA. MRI included assessment of biventricular function, aortic and pulmonary artery(PA) flow, and right ventricular (RV) overload using the ratio of RV-to-biventricular diameter. Except in one patient, who died 2 months post-surgery, clinical improvement occurred early after PEA (NYHA class: 3.3 +/- 0.6 to 1.5 +/- 0.8, p < 0.0001) with a decrease of systolic pulmonary artery pressures (79 +/- 14 to 44 +/- 14 mmHg, p < 0.0001). ⋯ RV overload decreased early after PEA (ratio RV-to-biventricular diameter: before: 0.67 +/- 0.04, after: 0.54 +/- 0.06, p < 0.0001), showing a good correlation with the improvement in RVEF (r = 0.7, P < 0.0001). In conclusion, reversed cardiac remodeling occurs early after PEA, to slow down after 1 month. At 6 months, cardiac remodeling is incomplete as witnessed by low-normal RV function and residually elevated PA pressures.
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Single-shot fast spin-echo (SSFSE)-based magnetic resonance imaging (MRI) has been introduced as a technique with less distortion and fewer artifacts for diffusion tensor imaging (DTI). The purpose of this study was to compare mean diffusivity maps, fractional anisotropy (FA) maps, and three-dimensional white-matter tractography using data obtained with SSFSE diffusion-tensor MRI technique and the much more common DTI method, echo-planar imaging (EPI), in the brain using a 1.5-Tesla clinical MR imager. Thirty patients with neurological disorders were scanned with both SSFSE-DTI and EPI-DTI using comparable scan times. ⋯ However, demonstration of three-dimensional fiber-tracking of white matter on SSFSE-DTI was inferior to that on EPI-DTI. In conclusion, SSFSE-DTI is a promising alternative to conventional EPI-DTI imaging, producing fewer image artifacts and geometric distortions. However, for 3D streamline fiber-tracking, EPI data produced more consistent and reliable results.
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The aim of this study was to assess the feasibility of diffusion tensor imaging (DTI) of the prostate and to determine normative fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of healthy prostate with a 3-Tesla magnetic resonance imaging (MRI) system. Thirty volunteers with a mean age of 28 (25-35) years were scanned with a 3-Tesla MRI (Intera Achieva; Philips, The Netherlands) system using a six-channel phased array coil. Initially, T2-weighted turbo spin-echo (TSE) axial images of the prostate were obtained. ⋯ Mean FA of the central gland was significantly higher (0.26), compared with the peripheral gland (0.16) (P < 0.01). This study shows the feasibility of prostate DTI with a 3-Tesla MR system and the normative FA and ADC values of peripheral and central zones of the normal prostate. The results are compatible with the microstructural organization of the gland.
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Comparative Study
Comparison of MR enteroclysis with MR enterography and conventional enteroclysis in patients with Crohn's disease.
To prospectively compare the diagnostic accuracy of MR enteroclysis with duodenal intubation with MRI after drinking oral contrast agent only (MR enterography) with conventional enteroclysis (conv-E) as reference standard in patients with Crohn's disease. Forty consecutive patients (22 males and 18 females; mean age 36; range 16-74 years) with proven Crohn's disease underwent conv-E and MR imaging. Twenty-two patients underwent MR enteroclysis with intubation (MRE) and 18 underwent MR-enterography (MR per OS). ⋯ The number of detected mesenteric findings was significantly higher with both MRE and MR per OS compared to conv-E (P < 0.01). MRE can serve as the diagnostic procedure for initially evaluating patients suspected of having Crohn's disease. MR per OS may have a role in patients that refuse or have failed intubation and also for follow-up.
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The piriformis syndrome is an uncommon cause of sciatica, buttock or thigh pain. Because of the deep location of the muscle and sciatic nerve, infiltration has traditionally been guided by electromyography, fluoroscopy, computed tomography or magnetic resonance imaging. ⋯ This technique was used satisfactorily in ten patients. Although the series in the study is limited, the procedure for US-guided infiltration of the perisciatic nerve is a quick, simple, economical and effective technique and can be considered an alternative in the percutaneous treatment of the piriformis syndrome.