[Infrarenal aortic ectasia in retroperitoneal fibrosis (RPF)]. / Aufweitungen der infrarenalen Aorta bei retroperitonealer Fibrose (RPF).

We analysed the infrarenal aortic morphology by abdominal MR-examinations of 47 RPF patients compared to a control group. A significant larger aortic calibre and higher rates of infrarenal dilatation in male RPF patients were observed. The larger aortic diameter in male RPF patients may be due to periaortic inflammation with resulting aortic ectasia and supports the classification of RPF into the spectrum of chronic periaortitis.

Stridor caused by duplication cyst in a female infant and temporary vocal cord paralysis. A case report.

INTRODUCTION AND IMPORTANCE: Congenital hypopharynx duplication cysts are a medical rarity; nevertheless, they offer an important differential diagnosis in neonatal dyspnea or feeding problems. CASE REPORT: Herein, we describe a case of delayed diagnosis but successful surgical removal of a large congenital hypopharynx cyst in a 4-month-old infant presenting with stridor. CLINICAL DISCUSSION: Early and proper diagnosis and surgical handling of hypopharynx cyst can help to achieve the best prognosis and outcome. CONCLUSION: We present the successful management of a newborn with a pharyngeal duplication cyst. In our case, the temporary postoperative laryngeal nerve palsy resolved within four weeks. Overstretching of recurrent laryngeal nerve might have caused this complication.

Evaluation of a resorbable, in situ setting bone substitute in a sheep model.

The gold standard for bone substitution is the autologous bone graft, but because of its limited supply and the associated morbidity, the search for synthetic alternatives is necessary. A new in situ setting tricalcium phosphate cement was implanted in a trepanation defect (9.4 mm diameter, 10 mm depth) in the distal femoral epiphysis of sheep. Empty cavities and autologous bone graft were used as controls. Histologic and histomorphometric examinations were carried out after 12 weeks. Nearly 90% of the implanted cement was resorbed and replaced by ingrown bone with close contact between surrounding bone, new bone, and remaining cement particles. The amount of bone in the defect area was significantly higher in defects filled with cement relative to defects filled with autologous bone graft (mean 27 vs. 21%, 95% confidence intervals 23 to 31 and 18 to 23, p = 0.026). In conclusion, this new in situ setting cement is bioactive, resorbable, and osteoconductive. It will be useful as an alternative to autologous bone graft to fill stable defects.

Diffusion-weighted MRI findings of treated and untreated retroperitoneal fibrosis.

PURPOSE: We aimed to evaluate diffusion-weighted imaging (DWI) findings in patients with treated and untreated retroperitoneal fibrosis (RPF). METHODS: We analyzed magnetic resonance imaging examinations of 44 RPF patients (36 male, 8 female), of which 15 were untreated and 29 were under therapy. Qualitative DWI and T1 postcontrast signal intensities and the largest perivascular extent of RPF were compared between treated and untreated groups and correlated to erythrocyte sedimentation rate and C-reactive protein values. Quantitative DWI signal intensities and apparent-diffusion-coefficients were calculated in regions-of-interest, together with a relative index between signal intensities of RPF and psoas muscle in 15 untreated patients and 14 patients under treatment with remaining perivascular fibrosis of more than 5 mm. RESULTS: The extent of RPF in untreated patients was significantly larger compared with the extent of RPF in treated patients (P <0.0001). DWI signal intensities were significantly higher in untreated patients than in patients under therapy (mean, 27 s/mm2 vs. 20 s/mm2; P = 0.009). The calculated DWI-index was significantly higher in untreated patients than in patients under therapy (P = 0.003). CONCLUSION: Our data show significant differences in the DWI findings (b800 signal intensities and relative DWI-index) of patients with treated and untreated RPF. DWI is a promising technique in the assessment of disease activity and the selection of patients suitable for medical therapy.

The potential role of modern US in the follow-up of patients with retroperitoneal fibrosis.

PURPOSE: We aimed to evaluate a standardized ultrasonography (US) algorithm for the visualization of pathologic para-aortic tissue in retroperitoneal fibrosis (RPF). MATERIALS AND METHODS: Thirty-five patients with lumbar RPF of typical extent, as determined by abdominal magnetic resonance imaging, were included. Examinations were conducted using standardized abdominal US with axial sections obtained at the levels of the renal arteries, aortic bifurcation, and both common iliac arteries. Imaging of each section was acquired with fundamental B-mode (US) and tissue harmonic imaging, respectively. In addition, we examined RPF visualized using extended field-of-view US. RESULTS: Tissue harmonic imaging adequately visualized RPF of typical extent in 33 patients (94.2%). Excellent and good visualization with mild artifacts were achieved in 25 (71.4%) and six (17.1%) patients, respectively. When RPF spread along the iliac arteries, excellent visualization was achieved in 38.7% for the left side and 34.5% for the right side. There were significantly fewer diagnostic examinations for the right iliac (27.6%) than for the left one (9.7%) (P = 0.016). Overall, harmonic imaging achieved significantly better visualization than fundamental B-Mode (P < 0.001). CONCLUSION: We described the first systematic evaluation of RPF visualization by modern US techniques. The best imaging quality was found in the typical RPF location, at the level of the aortic bifurcation. These results advocate for the presented US algorithm as an efficient follow-up alternative to cross-sectional imaging in RPF patients.

An aid to decision-making in therapy of retroperitoneal fibrosis: dynamic enhancement analysis of gadolinium MRI.

BACKGROUND: Idiopathic retroperitoneal fibrosis (IRF) as an uncommon cause of obstructive uropathy is often primarily treated medically by the attending urologist. We evaluated dynamic enhancement analysis (DEA) as a possible predictor of response to medical treatment and for treatment monitoring. METHODS: From 2007, 24 patients with fibrosis were assessed by magnetic resonance imaging (MRI) with DEA. The dynamic enhancement quotient (DEQ) was measured before therapy with prednisone (n = 12) or tamoxifen (n = 12) and in follow-up investigations after 3 and 6 months. Response to medical treatment was recorded by changes in the retroperitoneal mass on MRI and possible relief of ureteral obstruction, which was monitored by intravenous pyelogram and/or MAG3 scan after removal of DJ stents. RESULTS: Treatment groups did not differ significantly as to age, gender, or laboratory values, and response to medical treatment showed no significant difference between agents. Overall there were no cases of progression, 2 cases of stable disease, 11 cases of mild fibrotic regression, and 11 of significant or complete regression. DJ stents could successfully be removed in 21 of 35 renal units (60.0%). In a total of 61 DEAs the DEQ was significantly higher (P < 0.001) in patients with a good response (DEQ = 4.02) than in those with an average response (3.11) or none (2.14). CONCLUSIONS: DEA was able to distinguish between patients with different response rates to medical treatment of IRF and may be useful to individualize therapeutic decision-making.

Workflow optimization in vertebrobasilar occlusion.

OBJECTIVE: In vertebrobasilar occlusion, rapid recanalization is the only substantial means to improve the prognosis. We introduced a standard operating procedure (SOP) for interventional therapy to analyze the effects on interdisciplinary time management. METHODS: Intrahospital time periods between hospital admission and neuroradiological intervention were retrospectively analyzed, together with the patients' outcome, before (n=18) and after (n=20) implementation of the SOP. RESULTS: After implementation of the SOP, we observed statistically significant improvement of postinterventional patient neurological status (p=0.017). In addition, we found a decrease of 5:33 h for the mean time period from hospital admission until neuroradiological intervention. The recanalization rate increased from 72.2% to 80% after implementation of the SOP. CONCLUSION: Our results underscore the relevance of SOP implementation and analysis of time management for clinical workflow optimization. Both may trigger awareness for the need of efficient interdisciplinary time management. This could be an explanation for the decreased time periods and improved postinterventional patient status after SOP implementation.

Magnetic resonance imaging of the brain in children with headache: the clinical relevance with modern acquisition techniques.

The aim of this study was to evaluate the frequency of abnormal findings in magnetic resonance imaging (MRI) in children with headache, the clinical relevance of these findings, and whether more sophisticated technologies also result in more relevant abnormal findings. The MRIs of 1004 children with age ranging from 1 to 17 years were retrospectively analyzed. Children who were investigated with established sequences (n = 419) were compared with those examined with state-of-the-art MRI acquisition technology (n = 585). In 216/1004 investigations, MRI was performed because of headache (74/216 with established sequences, 142/216 with state-of-the-art acquisition technology). In 114/216 (52.8%) patients with headache, the MRI was abnormal with relevant findings in 23/114 patients and findings without clinical relevance in 91/114 children. A higher incidence of abnormal findings than in previous reports was found but there was only limited clinical gain of information using modern sequences in children with headache.

Endovascular treatment of dysfunctional hemodialysis catheters.

Hemodialysis-catheter dysfunction is a common clinical condition in nephrology. Like other central venous devices, hemodialysis-catheters show a disposition for partial or complete thrombotic obstruction and fibrin sleeve formation. Thrombolytic infusion is recommended as therapy of first choice. Alternative interventional strategies include over-the-wire catheter exchange, mechanical fibrin sleeve stripping with a snare and angioplastic sleeve disruption. Those approaches show extremely variable results with mediocre long-term patency rates. Therefore, catheter-avoiding strategies should be considered in detail and AV-fistula creation preferred.

Treatment for acetabular dysplasia using the uncemented RM acetabular component - a 20 year follow-up.

Our study reports a sub-group of patients with developmental dysplasia from a previously published larger series, with particular emphasis on the use of the uncemented RM acetabular component. We evaluated the long term results of 93 consecutive uncemented THAs in 80 patients using the titanium-coated RM acetabular component and the CLS femoral component in a prospective study. Eighteen hips in 16 patients had osteoarthritis secondary to developmental dysplasia of the hip. The mean follow-up was 19.6 years (18.2 to 20.9). Fourteen patients with 15 hips were clinically and radiographically examined and evaluated. Two patients with 3 hips died. No patient was lost to follow-up. No implant had to be revised, and no cases showed evidence of radiographic loosening. Nine acetabular components were not completely covered by host bone but this did not affect the outcome. At the latest follow-up the mean Harris Hip Score was 92 (81 to 100). The mean annual wear rate was 0.12 mm. The RM acetabular component performed well over 20 years in this selected group of patients. Complete acetabular containment was not needed, thus allowing reliable reconstruction of the anatomical centre of rotation.

Pulmonary embolism: comparison of angiography with spiral computed tomography, magnetic resonance angiography, and real-time magnetic resonance imaging.

In the last decade, spiral computed tomography (CT) and magnetic resonance (MR) angiography (MRA) have become a viable alternative to conventional angiography in the diagnosis of acute pulmonary embolism. However, patients with dyspnea are often unable to hold their breath for a longer time and thus image degradation is frequently observed. Consequently, an imaging sequence that allows free breathing is desirable. The aim of this animal study was to compare contrast-enhanced spiral CT, MRA and a real-time MR sequence, the latter without breath-hold, with pulmonary angiography as reference gold standard. Nine pigs with artificially induced pulmonary embolism underwent this multimodality comparison. All images were independently evaluated for the presence of pulmonary emboli by two reviewers. Forty-three filling defects were detected by conventional angiography on lobar and segmental levels. Sensitivity of CT images was 72.1 and 69.8% for Readers 1 and 2, respectively, and sensitivity of MRA images was 79.1 and 81.4%. With real-time MR imaging, however, the detection rate was 97.7% for both readers. We conclude that, under experimental conditions, real-time MR imaging without the use of radiation or iodinated contrast material is comparable with angiography in the detection of pulmonary emboli.