Radiologically inserted gastrostomy: differences of maintenance of balloon- vs. loop-retained devices.

PURPOSE: To compare outcome and associated complications of ballon- vs. loop-retained devices for radiologically inserted gastrostomy (RIG). METHODS: From 2007 to 2011 233 patients (age 63.7 ± 10.6 years) were referred for a RIG because of pharyngeal stricture Intervention was performed with four different devices: balloon-retained - Freka® GastroTube, Fresenius Kabi (n = 121); MIC® Gastrostomy Feeding Tube, Kimberly-Clark (n = 34); Russell® Gastrostomy Tray, Cook Medical Inc. (n = 17); and loop-retained - Tilma® Gastrostomy Set, Cook Medical Inc. (n = 50). Follow-up was performed with regard to RIG-related complications, cause of removal and fatalities. Revision-free survival times after RIG were evaluated using Kaplan-Meier analysis and group differences by log-rank tests. For analysis of demographic and methodical variables multivariate Cox regression models were used. RESULTS: With a primary technical success rate of 95.3% (222/233) a total of 92 instances of revisions were necessary in 66 patients (66/233, 28.3%) during follow-up (mean 182.8 ± 86.6 days). The most common complication was tube dislodgement (14.3%). There were no significant differences between the distinct devices (p = 0.098), but analyzing the data in subgroups of balloon-compared to loop-retained gastrostomy tubes we observed a significantly higher probability of minor complications for the latter (p = 0.023). CONCLUSION: As it is significantly less prone to minor complications we recommend the use of balloon-retained gastrostomy tubes to improve the practicability and maintenance of RIG.

Comprehensive analysis of dural ectasia in 150 patients with a causative FBN1 mutation.

The purpose of this study was to perform a comprehensive study of dural ectasia (DE) related to FBN1 mutations. We performed a database analysis of two German metropolitan regions of 150 patients (68 men, 82 women; mean age 35 ± 16 years). All patients had a FBN1 mutation and underwent dural magnetic resonance imaging. Age was <16 years in 20, 16-25 in 27, 26-35 in 67, and >35 in 36 patients. Prevalence of dural ectasia was 89% with criteria of Oosterhof and Habermann, 83% with Fattori, 78% with Lundby, and 59% with Ahn. DE was less frequent in patients <16 years with Ahn and Fattori. DE related to skeletal manifestations with all criteria, to aortic Z-scores and mitral valve prolapse with criteria of Habermann and Lundby, and to age with criteria of Fattori. The Fattori-grade of DE increased with age, aortic Z-scores, and skeletal score points. There was no consistent relationship of DE with any type of FBN1 mutation. DE is frequent in patients with FBN1 mutations irrespective of age and its severity increases during life. Criteria of Oosterhof and Habermann yielded most consistent diagnostic results. DE relates to skeletal involvement, aortic Z-scores, and mitral valve prolapse.

Dural ectasia in Loeys-Dietz syndrome: comprehensive study of 30 patients with a TGFBR1 or TGFBR2 mutation.

The purpose of this study was to assess the frequency, severity, and clinical associations of dural ectasia (DE) in Loeys-Dietz syndrome (LDS). Database analysis of three German metropolitan regions identified 30 patients with LDS and TGFBR1 mutation in 6 and a TGFBR2 mutation in 24 individuals (17 men; mean age: 31 ± 19 years), as well as 60 age and sex-matched control patients with Marfan syndrome carrying a FBN1 mutation. DE was present in 22 patients with LDS (73%), and it related to skeletal score points (p = 0.008), non-skeletal score points (p < 0.001), and to the presence of ≥7 systemic score points (p = 0.010). Similarly, the severity of DE was related to body height (p = 0.010) and non-skeletal score points (p = 0.004). Frequency (p = 0.131) and severity of DE (p = 0.567) was similar in LDS and Marfan syndrome. DE is a manifestation of LDS that occurs with similar frequency and severity as in Marfan syndrome. Severity of DE may serve as a marker of the overall connective tissue disease severity. LDS may be considered in patients with DE.

Analysis of phenotype and genotype information for the diagnosis of Marfan syndrome.

Marfan syndrome is considered a clinical diagnosis. Three diagnostic classifications comprising first, Marfan genotype with a causative FBN1 gene mutation; second, Marfan phenotype with clinical criteria of the original Ghent nosology (Ghent-1); and third, phenotype with clinical criteria of its current revision (Ghent-2) in 300 consecutive persons referred for confirmation or exclusion of Marfan syndrome (150 men, 150 women aged 35 ± 13 years) were used. Sequencing of TGBR1/2 genes was performed in 128 persons without FBN1 mutation. Marfan genotype was present in 140, Ghent-1 phenotype in 139, and Ghent-2 phenotype in 124 of 300 study patients. Marfan syndrome was confirmed in 94 and excluded in 129 persons consistently by all classifications, but classifications were discordant in 77 persons. With combined genotype and phenotype information confirmation of Marfan syndrome was finally achieved in 126 persons by Ghent-1 and in 125 persons by Ghent-2 among 140 persons with Marfan genotype, and exclusion was accomplished in 139 persons by Ghent-1 and in 141 persons by Ghent-2 among 160 persons without Marfan genotype. In total, genotype information changed final diagnoses in 22 persons with Ghent-1, and in 32 persons with Ghent-2. It is concluded that genotype information is essential for diagnosis or exclusion of Marfan syndrome.

Dural ectasia in individuals with Marfan-like features but exclusion of mutations in the genes FBN1, TGFBR1 and TGFBR2.

Mutations in the genes FBN1, TGFBR1, and TGFBR2 can result in heritable connective tissue disorders comprising the Marfan syndrome and the Loeys-Dietz syndrome. Dural ectasia is a characteristic manifestation of both syndromes. However, dural ectasia has not yet been investigated in connective tissue disorders that are unrelated to mutations in the FBN1, TGFBR1 or TGFBR2 genes. Here, we assessed dural ectasia in 33 individuals both with typical manifestations of heritable connective tissue disease and in whom mutations in all three genes had been excluded. We identified 19 individuals with dural ectasia (58%), who exhibited major skeletal manifestations of the Marfan syndrome more frequently than the remaining 14 persons without dural ectasia (p = 0.06). Moreover, only persons with dural ectasia fulfilled clinical criteria of the Marfan syndrome (p = 0.01). Conversely, aortic aneurysm (12 patients; p = 0.8), aortic dissection (five patients; p = 0.1), spontaneous dissection of the carotid arteries (five patients; p = 1), and mitral valve prolapse (13 patients; p = 0.4) were similarly frequent irrespective of dural ectasia. We conclude that dural ectasia is a marker for connective tissue disease which coincides with skeletal rather than with cardiovascular manifestations, and which may involve currently uncharacterized pathogenetic mechanisms and syndromes.

Interventional management of intractable sympathetically mediated pain by computed tomography-guided catheter implantation for block and neuroablation of the thoracic sympathetic chain: technical approach and review of 322 procedures.

We retrospectively evaluated the safety and efficacy of computed tomography-guided placement of percutaneous catheters in close proximity to the thoracic sympathetic chain by rating pain intensity and systematically reviewing charts and computed tomography scans. Interventions were performed 322 times in 293 patients of mean (SD) age 59.4 (17.0) years, and male to female ratio 105:188, with postherpetic neuralgia (n = 103, 35.1%), various neuralgias (n = 88, 30.0%), complex regional pain syndrome (n = 69, 23.6%), facial pain (n = 17, 5.8%), ischaemic limb pain (n = 7, 2.4%), phantom limb pain (n = 4, 1.4%), pain following cerebrovascular accident (n = 2, 0.7%), syringomyelia (n = 2, 0.7%) and palmar hyperhidrosis (n = 1, 0.3%). The interventions were associated with a total of 23 adverse events (7.1% of all procedures): catheter dislocation (n = 9, 2.8%); increase in pain intensity (n = 8, 2.5%); pneumothorax (n = 3, 0.9%); local infection (n = 2, 0.6%); and puncture of the spinal cord (n = 1, 0.3%). Continuous infusion of 10 ml.h(-1) ropivacaine 0.2% through the catheters decreased median (IQR [range]) pain scores from 8 (6-9 [2-10]) to 2 (1-3 [0-10]) (p < 0.0001). Chemical neuroablation was necessary in 137 patients (46.8%). We conclude that this procedure leads to a significant reduction of pain intensity in otherwise obstinate burning or stabbing pain and is associated with few hazards.

Incidentally detected splenic lesions in ultrasound: does contrast-enhanced ultrasonography improve the differentiation of benign hemangioma/hamartoma from malignant lesions?

PURPOSE: The aim of the study was to identify and validate enhancing features for differentiating benign vascular neoplasms of the hemangioma/hamartoma type from malignant splenic lesions on contrast-enhanced ultrasonography (CEUS). MATERIALS AND METHODS: 136 splenic lesions (58 benign vascular neoplasms, 78 malignant) in 136 patients underwent baseline US and pulse-inversion CEUS after sulfur hexafluoride-filled microbubble injection. Two on-site readers assessed lesion enhancement features during arterial and parenchymal phase in consensus. Best predicting CEUS features for lesion diagnosis were identified through univariate and multivariate analyses. Two blinded off-site readers independently issued a confidence rating for lesion diagnosis in baseline US and CEUS using extracted diagnostic CEUS features. Diagnostic performance, receiver operating curves (Az-value), and interreader agreement were calculated. The reference standards were histopathology or CT and/or MR imaging with clinical follow-up.  RESULTS: Multivariate analysis outlined arterial hyperenhancement or isoenhancement to be an independent CEUS predictor of benign vascular neoplasms (odds ratio, 3.558; p < 0.0017). Within the subgroup of isoechoic or hypoechoic lesions, arterial hyperenhancement was virtually diagnostic for benign vascular neoplasm (odds ratio, 21.333; p < 0.001). The diagnostic accuracy and confidence (Az-value) of the two readers was 63.2 % and 70.6 % (0.785 and 0.818) for baseline US, which improved significantly to 87.5 % and 88.2 % (0.915 and 0.908) for CEUS (p < 0.001). Interreader agreement also increased with CEUS (қ = 0.88) compared to baseline US (қ = 0.52). CONCLUSION: Sulfur hexafluoride-enhanced CEUS improves differentiation between benign vascular and malignant splenic tumors and may be especially useful in clinical scenarios in which the incidental hypoechoic splenic lesion is unclear on conventional US.

Aortic aneurysms after correction of aortic coarctation: a systematic review.

Despite advanced techniques for surgical or percutaneous therapy coarctation of the aorta continues to carry a high risk of aneurysmal formation. Mortality of these aneurysms ranges between <1 and >90%, reflecting remarkable differences in surgical strategies and the follow-up management of coarctation. We review the frequency, anatomical types, risk factors and mechanisms of aortic aneurysm forming late after surgical or percutaneous therapy of aortic coarctation. We emphasize that aneurysms do not form exclusively at the site of previous intervention, but also at remote locations such as the ascending aorta. Moreover, aneurysm formation may only in part be attributed to a specific technique of coarctation therapy, and we emphasize the role of a bicuspid aortic valve and inherent weakness of the aortic wall as significant risk factors for aneurysm after aortic coarctation. We report the presenting symptoms, follow-up protocols, and imaging criteria for local and proximal aneurysms. Finally, we discuss criteria for prophylactic intervention at the site of such aneurysms, and present therapeutic options for different types of aneurysms. With this systematic review, we wish to provide data for establishing more uniform strategies for preventing, diagnosing and treating aneurysms associated with aortic coarctation.

[Osteoid osteoma. X-ray-controlled resection and histologic verification using a minimally invasive diamond bone-cutting system]. / Osteoidosteom. Minimal-invasive, bildwandlergesteuerte Resektion und histopathologische Diagnosesicherung mittels Diamanthohlfräsen.

BACKGROUND: In recent years, osteoid osteomas have been treated more frequently by means of percutaneous procedures. The main disadvantage in patients with suspected osteoid osteoma is the lack of histological verification. Our study presents the results that we obtained using a minimally invasive diamond bone-cutting system allowing histologic verification. MATERIALS AND METHODS: Six patients (age 10-20 years) with osteoid osteoma in the lower extremities were subjected to resection of the nidus using a minimally invasive water-cooled diamond bone-cutting system. All specimens were histologically processed and diagnosed. RESULTS: In all patients the nidus was resected successfully, and the diagnosis was histologically confirmed. The mean operating time was 22.8 min. All patients were allowed full weight-bearing immediately, and hospitalization was a maximum of 2 days. All patients were free of pain and relapse-free during the entire 2-year postoperative follow-up. CONCLUSION: In selected localizations with a clearly visible nidus, the minimally invasive diamond bone-cutting system presented here offers an alternative to the established surgical and percutaneous procedures for treating osteoid osteomas. This procedure combines the advantages of a minimally invasive technique with the option of histological verification of the diagnosis and correct nidus ablation.

Variability of non-clinical behavioral CNS safety assessment: An intercompany comparison.

INTRODUCTION: Irwin/FOB testing is routinely conducted to investigate the neurofunctional integrity of laboratory animals during preclinical development of new drugs, however, the study design frequently varies to meet specific needs. Representatives of several European-based pharmaceutical companies performed a "state-of-the-art" assessment of how they conduct their CNS safety evaluation using Irwin/FOB tests. METHODS: This assessment consisted of (1) a survey of current/historical practice, (2) an evaluation of historical studies with reference compounds (amphetamine, chlorpromazine) to determine intercompany reproducibility of results, and (3) an interlaboratory test using reference compounds (MK-801, chlorpromazine) to determine whether partially standardized conditions (animals, sex, doses, vehicles, administration route, observation time points, systemic exposure) might reduce variability of results. RESULTS: Our survey revealed several similarities, e.g., main endpoints of home cage and openfield observations, species, and positive control substances, but also a high level of heterogeneity between different companies with regard to behavioral endpoints during handling and reflex testing, scoring, group size, and timing of studies. Analysis of heterogeneously designed historical studies with amphetamine and chlorpromazine showed the anticipated behavioral changes, albeit with quantitative variability, and identified more robust (e.g., activity, posture, muscle tone, startle reflex, body temperature) and less robust (piloerection, stereotypical behavior, palpebral closure, respiration) Irwin/FOB parameters. A partially standardized interlaboratory test with MK-801 and chlorpromazine showed the expected behavioral changes and principally confirmed the historically-based more/less robust Irwin/FOB parameters, however, it also showed exposure variability and did not show a markedly reduced quantitative variability of behavioral results. DISCUSSION: Our survey and intercompany test results demonstrate certain heterogeneity in design and conduct of Irwin/FOB tests by pharmaceutical companies. Although the general behavioral profiles for the reference compounds were consistently found, quantitative variability of results remained even under partially standardized conditions. This suggests the importance of a high level of standardization with regard to the Irwin/FOB test modification used, scoring system, and observer training, in order to achieve an improved intercompany comparability of Irwin/FOB results.

Comparison between positron emission tomography using 2-[fluorine-18]fluoro-2-deoxy-D-glucose, conventional imaging and computed tomography for staging of breast cancer.

BACKGROUND: The presence, extent and localization of distant metastases are key prognostic factors in breast cancer patients and play a central role in therapeutic decision making. The aim of this study was to compare the diagnostic performance of positron emission tomography using 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG-PET) with that of computed tomography (CT) and conventional imaging including chest radiography, abdominal ultrasound and bone scintigraphy. PATIENTS AND METHODS: A total of 119 consecutive patients with newly diagnosed locally advanced disease (n = 69) or previous history of breast cancer (n = 50) who had clinical suspicion of metastatic disease underwent FDG-PET, CT and conventional imaging procedures. Imaging results were retrospectively compared with histopathology and clinical follow-up which served as a reference standard. RESULTS: FDG-PET detected distant metastases with a sensitivity of 87% and a specificity of 83%. In contrast, the sensitivity and specificity of combined conventional imaging procedures were 43% and 98%, respectively. CT revealed a sensitivity of 83% and a specificity of 85%. CONCLUSIONS: In breast cancer, FDG-PET is superior to conventional imaging procedures for detection of distant metastases. Although FDG-PET and CT provided similar diagnostic accuracy, the information was often found to be complementary. With increasing availability of FDG-PET/CT, prospective studies are needed to determine whether it could potentially replace the array of conventional imaging procedures used today.

[Detection of metastases in breast cancer patients: comparison of FDG PET with chest X-ray, bone scintigraphy and ultrasound of the abdomen]. / Nachweis von Metastasen bei Patientinnen mit Mamma - karzinom Vergleich von FDG-PET mit Röntgen-Thorax, Oberbauchsonographie und Skelett szintigraphie.

UNLABELLED: Distant metastases at primary diagnosis are a prognostic key factor in breast cancer patients and play a central role in therapeutic decisions. To detect them, chest X-ray, abdominal ultrasound, and bone scintigraphy are performed as standard of care in Germany and many centers world-wide. Although FDG PET detects metastatic disease with high accuracy, its diagnostic value in breast cancer still needs to be defined. The aim of this study was to compare the diagnostic performance of FDG PET with conventional imaging. PATIENTS, METHODS: A retrospective analysis of 119 breast cancer patients who presented for staging was performed. Whole-body FDG-PET (n = 119) was compared with chest X-ray (n = 106) and bone scintigraphy (n = 95). Each imaging modality was independently assessed and classified for metastasis (negative, equivocal and positive. The results of abdominal ultrasound (n = 100) were classified as negative and positive according to written reports. Imaging results were compared with clinical follow-up including follow-up imaging procedures and histopathology. RESULTS: FDG-PET detected distant metastases with a sensitivity of 87.3% and a specificity of 83.3%. In contrast, the sensitivity and specificity of combined conventional imaging procedures was 43.1% and 98.5%, respectively. Regarding so-called equivocal and positive results as positive, the sensitivity and specificity of FDG-PET was 93.1% and 76.6%, respectively, compared to 61.2% and 86.6% for conventional imaging. Regarding different locations of metastases the sensitivity of FDG PET was superior in the detection of pulmonary metastases and lymph node metastases of the mediastinum in comparison to chest x-ray, whereas the sensitivity of FDG PET in the detection of bone and liver metastases was comparable with bone scintigraphy and ultrasound of the abdomen. CONCLUSIONS: FDG-PET is more sensitive than conventional imaging procedures for detection of distant breast cancer metastases and should be considered for additional staging especially in patients with high risk primary breast cancer.

[Sonography for evaluation of containment in perthes disease: a comparison with magnetic resonance imaging]. / Wertigkeit der Ultraschalluntersuchung in der Containmentdiagnostik des M. Perthes im Vergleich zur Magnetresonanztomografie.

PURPOSE: The objective of the present study was to investigate whether the sonographic visualization of lateralization of the femoral head is comparable to magnetic resonance imaging (MRI) and would therefore be able to contribute to the diagnosis of containment in patients with Perthes disease. MATERIALS AND METHODS: 46 patients with unilateral Perthes disease (age: 5.9 +/- 2.3 years) of Catterall group III/IV were evaluated at first presentation by means of ultrasound (US) and MRI of both hip joints to evaluate the morphology of the acetabular lip (LA) and the epiphysis (EP). The diagnosis of containment was performed in MRI as well as in US by the protrusion and deformity of the epiphysis of the femoral head with cranialization of the labrum. The evaluation of the sonographic and MRI findings was carried out independently by three observers (high experience: 1, 2, low experience: 3). Statistical analysis was performed using Cohen's non-weighted kappa kappa (kappa > 0.75 very high level of correlation). The study was conducted in accordance with the recommendations of the local ethics committee that approved our study. RESULTS: There was a high to very high agreement of the morphology of the LA and EP between observers 1 and 2 (MRI: LA: kappa = 0.87; EP: kappa = 0.90; US: LA kappa = 1.0; EP: kappa = 0.57). The comparison of observers 1 and 2 with observer 3 showed only a poor to acceptable level of agreement. US agreed well with MRI in the evaluation of the containment of the femoral head (1: kappa = 0.79; 2: kappa = 0.70, 3: kappa = 0.72). CONCLUSION: The results of our study suggest that US is a reliable examination method for monitoring the containment of the femoral head in Perthes disease. The evaluation of both methods depends on the experience of the observer.

Monitoring of gustatory stimulation of salivary glands by diffusion-weighted MR imaging: comparison of 1.5T and 3T.

BACKGROUND AND PURPOSE: Our aim was to compare different field strengths monitoring physiologic changes due to oral stimulation of parotid glands by using diffusion-weighted (DW) echo-planar imaging (EPI). MATERIALS AND METHODS: Twenty-seven healthy volunteers were examined with a DW-EPI sequence at 1.5T and 3T before and after oral stimulation with commercially available lemon juice. The b factors used were 0, 500, and 1000 s/mm(2). Apparent diffusion coefficient (ADC) maps were evaluated with a manually placed region of interest including the entire parotid gland. For comparison of results, a Student t test was used on the basis of the mean of the volunteer median values. To compare both field strengths, we calculated the Pearson correlation coefficient (r). RESULTS: DW-EPI MR imaging visualized the parotid glands of all volunteers. With 1.5T, the mean ADC before stimulation was 1.12 x 10(-3) mm(2)/s +/- 0.08 x 10(-3) mm(2)/s. After stimulation with lemon juice, the ADC increased to 1.18 x 10(-3) mm(2)/s +/- 0.09 x 10(-3) mm(2)/s. For 3T, the ADC before stimulation was 1.14 x 10(-3) mm(2)/s +/- 0.04 x 10(-3) mm(2)/s, with an increase to 1.17 x 10(-3) mm(2)/s +/- 0.05 x 10(-3) mm(2)/s after stimulation. For both field strengths, the increase in ADC after stimulation was significant (P < .001). High correlations between both field strengths were found pre- and poststimulation (r = 0.955, and 0.936, respectively). CONCLUSION: DW-EPI MR imaging allows monitoring of physiologic changes due to oral stimulation of parotid glands by using DW imaging with high correlation between 1.5T and 3T.

[MR sialography: evaluation of an ultra-fast sequence in consideration of a parallel acquisition technique and different functional conditions in patients with salivary gland diseases]. / MR-Sialographie: Prospektive Evaluation ultraschneller Sequenzen mit paralleler Bildgebung und oraler Stimulation bei Patienten.

PURPOSE: To evaluate an ultra-fast sequence for MR sialography requiring no post-processing and to compare the acquisition technique regarding the effect of oral stimulation with a parallel acquisition technique in patients with salivary gland diseases. MATERIALS AND METHODS: 128 patients with salivary gland disease were prospectively examined using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and a maximum slew rate of 125 mT/m/sec. A single-shot turbo-spin-echo sequence (ss-TSE) with an acquisition time of 2.8 sec was used in transverse and oblique sagittal orientation. All images were obtained with and without a parallel imaging technique. The evaluation of the ductal system of the parotid and submandibular gland was performed using a visual scale of 1-5 for each side. The images were assessed by two independent experienced radiologists. An ANOVA with post-hoc comparisons and an overall two tailed significance level of p = 0.05 was used for the statistical evaluation. An intraclass correlation was computed to evaluate interobserver variability and a correlation of > 0.8 was determined, thereby indicating a high correlation. RESULTS: Depending on the diagnosed diseases and the absence of abruption of the ducts, all parts of excretory ducts were able to be visualized in all patients using the developed technique with an overall rating for all ducts of 2.70 (SD +/- 0.89). A high correlation was achieved between the two observers with an intraclass correlation of 0.73. Oral application of a sialogogum improved the visibility of excretory ducts significantly (p < 0.001). In contrast, the use of a parallel imaging technique led to a significant decrease in image quality (p = 0,011). CONCLUSION: The applied ss-TSE for MR sialography allows fast and sufficient visualization of the excretory ducts of the main salivary glands in patients, and no elaborate post-processing is required. Use of an oral sialogogum is suggested to improve the results of MR sialography.

Cementless fixation of megaprostheses using a conical fluted stem in the treatment of bone tumours.

We reviewed 25 patients in whom a MUTARS megaprosthesis with a conical fluted stem had been implanted. There were three types of stem: a standard stem was used in 17 cases (three in the proximal femur, nine in the distal femur and five proximal tibia), a custom-made proximal femoral stem in four cases and a custom-made distal femoral stem in four cases. The mean age of the patients was 40.1 years (17 to 70) and the mean follow-up was for 2.5 years (0.9 to 7.4). At follow-up two patients had died from their disease: one was alive with disease and 22 were disease-free. One of 23 prostheses had been removed for infection and another revised to a cemented stem. The mean Musculoskeletal Tumor Society score was 24.9 (12 to 30) and the mean Karnofsky index was 82% (60% to 100%). There was no radiological evidence of loosening or subsidence. Stem stress shielding was seen in 11 patients and was marked in five of these. There were five complications, rupture of the extensor mechanism of the knee after extra-articular resection in two patients, deep venous thrombosis in one, septic loosening in one, and dislocation of the hip in one. The survival rate after seven years was 87% (95% confidence interval (CI) 83 to 91) for the patients and 95% (95% CI 91 to 99) for the megaprosthesis. A longer follow-up is needed to confirm these encouraging results.

[Functional imaging of submandibular glands: diffusion-weighted echo-planar MRI before and after stimulation]. / Diffusionsgewichtete MRT zur Funktionsdiagnostik der Glandula submandibularis.

PURPOSE: To investigate the feasibility of diffusion-weighted (DWI) echo-planar imaging (EPI) to depict the submandibular glands and to measure different functional conditions. MATERIALS AND METHODS: Twenty-seven healthy volunteers were examined. Diffusion weighted sequence was performed prior to stimulation. Exactly 30 seconds after a commercially available lemon juice was given orally, the diffusion weighted sequence was repeated. All examinations were performed by using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and maximum slew rate of 125 mT/m/sec (Magnetom Symphony, Siemens, Erlangen, Germany). The lower part of the circularly polarized (CP) head coil and a standard two-element CP neck array coil were used. The flexibility of the neck array coil allowed positioning the N1 element (upper part of the coil) right next to the submandibular gland. The axial diffusion-weighted EPI (echo planar imaging) sequence was performed using a matrix of 119 x 128, a field of view of 250 x 250 mm (pixel size 2.1 x 1.95 mm), a section thickness of 5 mm with an interslice gap of 1 mm. The b factors used were 0 sec/mm(2), 500 sec/ mm(2) and 1000 sec/mm(2). Apparent diffusion coefficiant (ADC) maps were digitally transferred to MRIcro (Chris Rorden, Universitiy of Nottingham, Great Britain). After detecting the submandibular glands a region of interest (ROI) was placed manually exactly within the boarder of both submandibular glands, excluding the external carotid artery on ADC maps. These procedures were performed on all ADC slices the submandibular glands could be differentiated in before and after oral stimulation. For statistical comparison of results, a student's t-test was performed with an overall two-tailed significance level of p = 0.05. RESULTS: The visualization of the submandibular glands using the diffusion-weighted EPI sequence was possible in all of the 27 volunteers. Prior to oral stimulation an ADC of 1.31 x 10(-3) mm(2)/sec (95 % CI, 1.39 x 10(-3) mm(2)/sec, 1.44 x 10(-3) mm(2)/sec) was calculated which increased to 1.41 x 10(-3) mm(2)/sec (95 % KI, 1.39 x 10(- 3) mm(2)/sec, 1.44 x 10(-3) mm(2)/sec) 30 seconds after stimulation. This increase proved to be significant (p < 0.001). CONCLUSION: Diffusion-weighted echo-planar MR imaging allows non-invasive quantification of functional changes in the submandibular gland.

[Imaging in rheumatology. Degenerative diseases of the spine]. / Bildgebende Verfahren in der Rheumatologie. Bildgebung bei degenerativen Erkrankungen der Wirbelsäule.

Degeneration of the spine is a common reason for pain in the musculoskeletal system. Radiography is an important tool for diagnosis and differential diagnosis. Cost efficacy and economy of time are advantages in using conventional x-rays. Although narrowing of intervertebral disc spaces, irregular ossification of the vertebral end-plate as well as osteophytes, facet joint osteoarthritis and spondylolisthesis can be observed, early changes in the discs or the subdiscal bone can not be detected by x-rays. Moreover, 3-dimensional imaging is not possible. Computer tomography (CT) and magnetic resonance imaging (MRI) are reliable for identifying disorders of the spine and soft-tissue. Differentiation between inflammation, trauma and tumor is possible. There is still a problem with the relationship between the information obtained by x-rays or MRI and clinical symptoms. Therefore, interpretation of radiological examinations assumes a knowledge of clinical symptoms and the different kinds of diseases which are possible.

[Osteochondritis Dissecans of the Talus - A Critical Review]. / Osteochondrosis dissecans tali ­ eine kritische Übersicht.

The etiology remains unclear. Mechanical factors seem to play an important role. Most histologies report clefts between the cartilage and bone and necrotic areas. Several classifications have been published based on observations from imaging techniques or on intraoperative findings. Clinical symptoms are unspecific. Imaging techniques are of great importance: X-rays of the ankle joint enable a quick diagnostic overview. MRT is the imaging-technique of choice for diagnosing OCDT-lesions. Regarding treatment, a tremendous number of retrospective publications exist. Only a few are classified as level I or II papers. Patients with open physes and low-grade lesions have good results with conservative therapy. Adults do not profit from a longer conservative procedure. Where surgery is necessary, the procedure depends on the stage of the lesion and on the state of the cartilage. With intact cartilage, retrograde procedures or transchondral drilling are to be favoured. Where the cartilage is damaged, several techniques can be used: while techniques such as drilling and microfracturing, or matrix-associated microfracturing produces repair cartilage, other techniques reconstruct the defect with osteochondral grafts or cell-based procedures such as chondrocyte transplantation. Regarding the outcome, it is difficult to make a precise, scientifically-based recommendation which has been confirmed by more than one prospective study. Only limited recommendations are possible: In juveniles with intact cartilage, initially conservative treatment is indicated. If there is no improvement, conservative invasive techniques such as drilling may help. In adults conservative therapy should be limited to a few weeks. Regarding the surgical treatment options, there is a tendency towards better results with procedures which reconstruct the bone and the cartilage and there is also a trend towards better long-term results when co-morbidities are treated. Severe grades of osteoarthrosis are rare.

Diffusion-weighted echo-planar MRI: a valuable tool for differentiating primary parotid gland tumors?

PURPOSE: To investigate the feasibility of using diffusion-weighted (DW) echo-planar imaging (EPI) for differentiating primary parotid gland tumors. MATERIAL AND METHODS: Fifty consecutive patients with a suspected primary tumor of the parotid gland were examined with a DW EPI sequence (TR 1,500 msec, TE 77 msec, field of view 250 x 250 mm, pixel size 2.10 x 1.95 mm, section thickness 5 mm). The b factors used were 0, 500, and 1,000 sec/mm (2). Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain) and evaluated with a manually placed irregular region of interest (ROI) containing the entire tumor. Additionally, the contralateral, non affected parotid gland was measured and a circular ROI containing 100 - 200 pixels was placed in the cerebrospinal fluid (CSF) next to the spinal cord in every patient. For comparison of the results, the two-tailed Student's t test was used, based on the median ADC values for each patient, and a p-value <.05 was determined to indicate statistical significance. RESULTS: In 45 patients, a primary neoplasm of the parotid gland could be histologically verified. For the non-affected parotid glands of all 45 evaluated patients, the mean ADC value was 1.14 x 10 ( - 3) mm (2)/sec +/- 0.12 x 10 ( - 3) mm (2)/sec (mean +/- standard deviation). Seven different entities of parotid gland tumors were histologically discriminated. Pleomorphic adenomas (2.14 x 10 ( - 3) mm (2)/sec +/- 0.11 x 10 ( - 3) mm (2)/sec), Warthin tumors (0.85 x 10 ( - 3) mm (2)/sec +/- 0.1 x 10 ( - 3) mm (2)/sec), and mucoepidermoid carcinomas (1.04 x 10 ( - 3) mm (2)/sec +/- 0.3 x 10 ( - 3) mm (2)/sec) showed statistically significant different ADC values in comparison to all other evaluated tumors (p .001), and also among each other (p <.001). Additionally, ADC values presented by lipomas were statistically significant compared to all other entities (p <.001 to .015). Among all other [corrected] primary malignant parotid gland tumors, no statistically significant ADC values could be observed (p .18 to 1). CONCLUSION: Diffusion-weighted echo-planar MRI seems to be a valuable tool for differentiating benign from malignant primary parotid gland tumors.