[Deep leg and pelvic vein thrombosis in a 4-year-old boy].
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Publications and source records attributed to M Steinborn.
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PURPOSE: To determine the detection of diffuse bone marrow infiltration with MRI in comparison with histopathological findings. MATERIALS AND METHODS: MRI was performed on 45 patients with histologically proven multiple myeloma and on 30 healthy individuals. Three experienced radiologists read separately Tl-weighted SE sequences, STIR sequences and the combination of Tl-weighted SE and STIR sequences of the spine. Additionally, Tl-weighted SE sequences were obtained after gadolinium administration and the percentage increase in signal intensity was calculated. Bone marrow histology was used as gold standard for assessing the grade of infiltration. A dichotomous decision (infiltration yes/no) was made when assessing the MRI examinations. RESULTS: For the visual detection of diffuse infiltration, the best sensitivity was found with Tl-weighted SE sequences, achieving 71 % on average. The specificity was 89 %. The STIR sequences showed a sensitivity of 61 % and a specificity of 98 %, and the combination of Tl-weighted/STIR-sequences achieved a sensitivity of 65 % and a specificity of 94 %. In comparison with the histological findings, the sensitivity of the Tl-weighted sequences was 35 % for low-grade, 89 % for moderate and 100 % for high-grade infiltration. The application of contrast material with calculation of the percentage signal increase improved the detection by 7 %. CONCLUSION: The sensitivity of the visual detection of diffuse multiple myeloma with unenhanced MRI is limited for low-grade or moderate infiltration, whereas the sensitivity for high grade infiltration is reliable. The specificity is high and the diagnostic confidence improves after application of contrast material with calculation of the percentage increase in signal intensity.
BACKGROUND: The problem of metal sensitivity (Ni, Cr, and Co) in arthroplasty is still unsolved. To prevent the risk of allergy in cases with proved metal allergy in an epicutaneous test, a Natural Knee total knee arthroplasty, made totally from titanium (Ti-6Al-4V) and polyethylene, can be implanted. The results of this device have to be compared to the results of normal knee arthroplasty designed with a femoral component out of CrCoNi alloy. The mechanical resistance of this alloy is much higher than that of titanium, and therefore it is the standard for the femoral components of most knee-resurfacing devices. METHODS: Thirty-five patients with a titanium Natural Knee were examined retrospectively after a mean follow-up of 2 years and 5 months (range 6 months to 5 years and 4 months). In comparison, 36 patients with a Genesis-I knee with a CrCoNi alloy femoral component were studied after a mean follow-up of 2 years and 4 months (range 8 months to 6 years and 2 months). RESULTS: In spite of the lower mechanical resistance of titanium, the Natural Knee showed better results (knee score 84.1 points, function score 77.7 points, HSS score 80.1 points, 82.9% excellent and good results) than the Genesis-I knee (knee score 80.6 points, function score 76.4 points, HSS score 76.4 points, 68.5% excellent and good results), although these differences had no statistical significance. CONCLUSIONS: The titanium Natural Knee prosthesis has proven to be a reliable knee joint replacement in the medium term.
AIM OF THE STUDY: The roentgenologic morphology of symptomatic calcified deposits of the rotator cuff can be classified according Gärtner. This classification influences therapeutic procedures and prognosis of clinical outcome in these patients. In the present study intraoberserver-reproducibility and interobserver-reliability of Gärtner's classification were tested. METHODS: Plane radiographs of 100 patients with calcifications of the supraspinatus tendon were classified according the criteria of Gärtner by 6 independent observers twice within 4 months. Intraoberserver-reproducibility and interobserver-reliability were calculated by means of Cohen's kappa-index. RESULTS: kappa-values of intraoberserver-reproducibility had a mean of 0.4208 (SD 0.1299), kappa-values of interobserver-reliability were 0.490 for the first and 0.474 for the second classification. CONCLUSIONS: Determination of intraoberserver-reproducibility gave insufficient to satisfactory results, interobserver-reliability was sufficient. The clinical use of Gärtner's classification to plan therapeutic procedures or to determine clinical prognosis in patients with calcifying tendinitis can be recommended only with limitations.
INTRODUCTION: CRPS I represents a frequent complication following distal radial fractures. Early diagnosis may prevent chronification of the disease. However posttraumatic pain, swelling and motor disturbances render the differentiation from normal fracture patients more difficult. The incidence of CRPS I in patients at risk and the diagnostic value of clinical evaluation, radiography and thermography in the early posttraumatic phase are analysed. METHODS: 158 consecutive patients with distal radial fractures were followed-up for 16 weeks after trauma. Apart from a detailed clinical examination 8 and 16 weeks after trauma, thermography and bilateral radiographs of both hands were performed. RESULTS: At the end of the observation period 18 patients (11%) were clinically identified as CRPS I. The severity of the preceding trauma and the chosen therapy did not influence the process of the disease. 16 weeks after trauma easy differentiation between normal fracture patients and CRPS I patients was possible. 8 weeks after distal radial fracture clinical evaluation showed a sensitivity of 78% and a specificity of 94%. Thermography (58%) however and bilateral radiography (33%) revealed a poor sensitivity, respectively. The specificity was high for radiography (91%) and again poor for thermography (66%), respectively. CONCLUSION: The results of the study support the importance of clinical evaluation in the early diagnosis of CRPS I. Plain radiographs facilitate the diagnosis as soon as bony changes develop.
Benign bone-forming tumors include osteomas, enostomas, osteoid osteomas, and osteoblastomas. These lesions are often characterized by typical imaging findings on radiographs, CT and MR imaging studies. Radiologic findings and additional clinical information allow for a specific diagnosis in most cases. This review article emphasizes the radiological patterns of benign bone-forming tumors as well as their epidemiological, clinical, and pathological characteristics. In addition, minimally invasive interventional procedures for the therapy of osteoid osteoma are reviewed.
Today the clinical use of extracorporeal shockwave application (ESWA) for the treatment of lateral tennis elbow is hampered by the lack of results from randomized controlled trials and of predictive parameters of clinical outcome. The present prospective study aimed to provide the latter by means of magnetic resonance imaging (MRI). Twenty-three female and 19 male patients with unilateral chronic tennis elbow of the dominant site were clinically examined before and after repetitive low-energy ESWA. MRI was performed before ESWA to evaluate signal intensity changes or contrast enhancement of the common extensor tendon and the lateral epicondyle. After ESWA (mean follow-up period 18.6 months for all patients), clinical evaluation showed a significantly better mean clinical performance after ESWA than before treatment. Interestingly, male patients showed a significantly better mean clinical performance after ESWA than female patients, and male and female patients differed significantly in the signal intensity of the common extension tendon cross-section and tendon thickening on MRI. For female patients, MRI scans could be applied for predicting a positive clinical outcome of ESWA. This study reports the first indication of predictability of positive clinical outcome of the treatment of chronic lateral tennis elbow by ESWA using imaging prior to treatment. This may serve as an important step towards overcoming the therapeutic nihilism with respect to the non-operative management of this condition recently in the literature.
MRI plays an important role in the diagnostic workup of skeletal metastases. In principle two different applications of MRI can be distinguished: apart from the well known indications of clarifying uncertain lesions seen with other imaging modalities or demonstrating known osseous lesions with high resolution imaging for therapeutic planing, MRI can also be used as a primary screening modality for skeletal metastases. Besides the higher lesion detection rate the major advantage of MRI compared to bone scintigraphy lies in the demonstration of morphology which on the one hand exactly shows the extension of tumorous lesions and on the other hand clearly distinguishes between malign and benign processes. As unclear findings on bone scintigraphy often require additional imaging studies, especially in patients with clinical findings or lab results suggestive for metastatic disease, we think that whole-body-skeletal-MRI is not only an accurate but also a cost effective diagnostic modality in the detection and screening for skeletal metastases, if the indication for the examination is closely related to clinical findings and the therapeutic relevance of the imaging results.
PURPOSE: To assess the value of MR imaging in demonstrating ongoing spondylolysis in adolescents. METHODS: MRI was performed in 9 juvenile patients (3 female, 6 male aged 8-16 years; mean 12.5 y) with pain during hyperextension. In 6 patients a CT scan and in 5 a plain film was available. RESULTS: In all patients bone marrow edema was found in the pars interarticularis and the pedicle, which was bilateral in 4 patients. In 7/9 cases the L5 vertebra was affected, in 2/9 cases spondylolysis was found in L4. In 3 cases the edema reached the middle third of the vertebral body and a tumor was suspected. In all CT scans a bilateral incomplete or complete cleft in the pars inter-articularis was found. In 4/6 CT-scans a sclerosis was seen in the area of the bone marrow edema. Only in 1/5 plain films was there a suspicion for a spondylolysis, four examinations were completely normal. CONCLUSIONS: To eliminate underlying causal conditions of spondylolysis and to install specific therapy, early diagnosis is mandatory. MR imaging should be the first and only imaging modality in young patients with low back pain during and after exercise and pain with hyperextension. Bone scans and CT scans should be avoided due to irradiation, plain films usually do not reveal pathological findings in developing sponylolysis.
OBJECTIVE: To clarify morphologic features associated with the clinical outcome of extracorporeal shock wave application (ESWA) in chronic plantar fasciitis. METHODS: In this prospective study 43 patients (48 heels) with chronic courses of plantar fasciitis were clinically examined before and after repetitive low energy ESWA. Standard radiographs of the affected heels were obtained before ESWA to document the existence of a calcaneal heel spur. Magnetic resonance imaging (MRI) was performed before ESWA to evaluate abnormalities of the plantar fascia, the surrounding soft tissue structures, and bone marrow edema of the calcaneus. RESULTS: After ESWA (mean followup 19.3 mo), clinical evaluation of all 48 heels revealed a statistically significant decrease in the mean visual analog scale score from 74.5 to 25.4. Using the Roles and Maudsley score (RM), an established scoring system for categorizing results of treatment following ESWA for patients with plantar fasciitis, patients could be divided into 2 groups, i.e., satisfactory clinical outcome of ESWA (grades 1 and 2 by RM scale; n = 36 heels) and unsatisfactory outcome (grades 3 and 4 by RM scale; n = 12 heels). While thickness of plantar aponeurosis, soft tissue signal intensity changes, and soft tissue contrast medium uptake did not correlate with clinical outcome, the presence of a calcaneal bone marrow edema was highly predictive for satisfactory clinical outcome (positive predictive value 0.94, sensitivity 0.89, specificity 0.8). CONCLUSION: This study indicates that in patients with chronic plantar fasciitis, the presence of calcaneal bone marrow edema on pretherapeutic MRI is a good predictive variable for a satisfactory clinical outcome of ESWA.
PURPOSE: Determination of the value of 13-MHz high-frequency ultrasound in the diagnosis of acute injuries of the lateral ankle ligaments and the anterior tibiofibular ligament by comparison with MRI. METHOD: Sonography was performed prospectively in 64 acutely injured patients using a mechanical 13-MHz sector probe; for diagnosis of the anterior tibiofibular ligament a 15-MHz sector probe was employed during the course of this trial. Using a 0.2-T unit for MRI examination, T1-weighted (TR 580 ms, TE 24 ms) and T2-weighted (TR 3000 ms, TE 80 ms) spin-echo sequences were obtained in various oblique axial imaging planes. RESULTS: In the differentiation of intact and injured ligaments, ultrasound and MRI agreed in 95.3% of cases for the anterior fibulotalar ligament, in 88.3% for the fibulocalcanear ligament and in 85.0% for the anterior tibiofibular ligament. CONCLUSION: Lesions of the anterior talofibular and fibulocalcanear ligament can be accurately demonstrated by ultrasound if a 13-MHz sector scanner is used. The detection of lesions in the anterior tibiofibular ligament is more difficult. With increasing experience and by using a 15-MHz sector scanner, better results can be expected for this ligament.
The purpose of this study was to evaluate MR imaging findings of the common extensor tendon in patients with lateral epicondylitis and asymptomatic volunteers studied on a 0.2-T dedicated system. In 23 patients (age range 29-58 years, mean age 47 years) with clinical symptoms of lateral epicondylitis MR imaging was performed using T1-, T2- and contrast-enhanced T1-weighted spin-echo sequences. In addition, the elbows of seven healthy volunteers (age range 22-29 years, mean age 25 years) and the symptom-free contralateral elbow of 11 of the 23 patients (age range 29-58 years, mean age 47 years) were studied as controls. Five patients were surgically treated after the MR examination and the results of histopathology were correlated with MR findings. Of the patients, 95.6 % showed intratendinous signal intensity changes on T1-weighted images on the symptomatic side. In 69.6 % signal alterations were observed on T2-weighted sequences and in 56.5 % an intratendinous contrast enhancement was present. Histopathology showed fibrovascular proliferation and fatty degeneration in patients with distinct signal intensity changes and contrast enhancement. Patients with only minor signal intensity changes on T1- and T2-weighted sequences and no contrast enhancement demonstrated fibrosclerotic degeneration and intratendinous cartilage formation in histopathology. The contralateral elbow showed signal intensity changes in 6 of 11 (54.5 %) cases on T1-weighted images and in 3 of 11 (27.3 %) on T2-weighted images. In the group of healthy volunteers minor signal intensity changes of the common extensor tendon could be seen in only 1 case. In patients with lateral epicondylitis of the elbow the type and extent of pathologic changes within the common extensor tendon can be evaluated using a dedicated low-field MR system. On the basis of MR imaging findings a more specified therapy planning among the variety of treatment modalities can be achieved.
We report on a 2.5-year-old boy with severe mental retardation, choreoathetosis, dystonia, muscle rigidity, opisthotonus and severe hearing impairment. He had history of severe hyperbilirubinaemia immediately after birth presumably due to ABO incompatibility. The history and the clinical picture suggested the diagnosis of Kernicterus. The MR imaging examination upon admission revealed bilateral signal intensity increase in the globus pallidum on T2-weighted sequences. Additionally, our patient showed signal intensity changes within the subthalamic nuclei, which is known to be another characteristic area of bilirubin deposition in Kernicterus.
PURPOSE: To compare Gadolinium-enhanced MR angiography with conventional DSA in the preoperative evaluation of living kidney donors. MATERIAL AND METHODS: 27 potential living kidney donors were examined with contrast-enhanced MR angiography after conventional angiography. The MR angiograms were evaluated for the number of renal arteries, the presence of early arterial branching and vascular pathologies by two independent readers. The results were compared with those of selective conventional angiography and intraoperative findings. RESULTS: Conventional angiography detected 14 accessory renal arteries. Reader A detected 13 of 14 accessory arteries with no false positive result (sensitivity 93%, specificity 100%). Reader B detected 11 of 14 accessory vessels with one false positive finding (sensitivity 79%, specificity 98%). Early arterial branching was detected by both readers in 9 of 12 vessels with no false positive result (sensitivity 75%, specificity 100%). None of the patients had additional vascular pathology. DISCUSSION: Gadolinium-enhanced MR angiography is a non-invasive alternative to conventional angiography in the preoperative evaluation of living kidney donors. In order to achieve high accuracy in detecting accessory renal arteries and early arterial branching extensive experience with the method and the specific preoperative needs is required. Selective conventional angiography is still superior in detecting very small accessory vessels and early arterial branching.
PURPOSE: The purpose of this study was to determine the type and frequency of characteristic bone and soft tissue changes on MRI of patients with a clinical diagnosis of plantar fasciitis. MATERIALS AND METHODS: 28 patients with a clinical diagnosis of plantar fasciitis underwent MR imaging. Besides T1- and T2-weighted sequences, short-tau-inversion-recovery sequences were used routinely. In 27 patients T1-weighted images after intravenous contrast injection were acquired additionally. As a control group the images of 15 patients without clinical signs for plantar fasciitis were evaluated. RESULTS: In 25 of 28 cases (89%) the clinical diagnosis of plantar fasciitis was established by MR imaging. The most common finding was a peritendinous edema at the calcaneal insertion site which was found in all 25 patients. In 19 of 25 cases (76%) a bone marrow edema of the calcaneus was present. In 14 of 25 cases (56%) an intratendinous signal intensity increase of the plantar fascia could be observed which showed contrast enhancement in 12 cases. Compared to the control group (mean thickness 3.3 mm) the plantar fascia showed significant thickening in the 25 MR positive patients (mean thickness 6.72 mm). DISCUSSION: Besides thickening of the plantar fascia and intratendinous signal intensity increase with contrast enhancement to some extent, bone marrow edema of the calcaneus and peritendinous edema close to the plantar fascia are characteristic signs of plantar fasciitis on MRI. Both signs can reliably be seen on STIR sequences only.
OBJECTIVE/PATIENTS: To investigate the efficacy of standard sequences of a low field system for the detection of osteomyelitis, we tested T1wI pre and post i.v. contrast, T2w and fat suppressed IR sequences. DESIGN: On the basis of clinical and laboratory evidence, pathology reports, and three phase granulocyte scintigraphy, osteomyelitis was diagnosed in 18 of 21 patients with Charcot's joints. A consecutive low and high field magnetic resonance (MR) scan confirmed osteomyelitic bone marrow changes in the same osseous regions. These 18 diabetic patients were then studied on a 0.2 Tesla dedicated MR system (Esaote ArtoScan) using T1wI (SE: relaxation time (TR) 520/echo time (TE) 24: axial and coronal) before and after i.v. application of 0.1 mmol/l Gd-DTPA/kg BW, T2w imaging (TSE: TR 3500/TE 80 or TR 2000/TE 120: axial), and fat suppressed inversion recovery (IR) imaging (short tau inversion recovery (STIR): TR 3000/TE 30/TI 80 or inversion recovery gradient echo (IRGE)/fat suppressed IRGE (GEFS): TR 1000/TE 16m 80: coronal). RESULTS: The SE T1w sequence showed a significantly higher contrast-to-noise ratio (CNR) before administration of i.v. contrast. The TSE T2w pulse sequence demonstrated bone marrow changes superiorily utilizing a TE of 120 ms (CNR = 16.5+/-2.7 compared to 5.5+/-2.5 with TE = 80 ms). The IRGE showed a higher CNR than the standard STIR (CNR = 19.2+/-2.5 compared to 12.4+/-2.9). CONCLUSION: Fat suppressed IRGE imaging and longer TE in T2w TSE sequences result in a significantly better CNR in osteomyelitis. This way, using optimized sequences, low field systems are apt to depict bone marrow changes in the course of osteomyelitis.
The purpose of the study was to determine the changes that might be detected using magnetic resonance imaging (MRI) on patients with chronic lateral epicondylitis of the elbow and to judge its value concerning the clinical treatment. Thirty-four patients with chronic lateral epicondylitis were included in a prospective study. All individuals underwent MRI of the elbow on a 0.2-T dedicated system. The MRI findings were interpreted by an independent radiologist without knowledge of the clinical findings. In 6 surgical cases an additional histological study was done. The biopsy of the extensor tendon was performed for correlation with the MRI. In 21 of 34 symptomatic patients, increased signal changes in T1- and T2-weighted images were seen. In a further 11 cases, the morphology and signal intensity were normal. The histopathological analysis of 6 surgical cases confirmed the preoperative MRI findings by showing either focal fibrous degenerative tendon tissue or microruptures of collagenous fibres. MRI in patients with chronic lateral epicondylitis can help to differentiate the disease and may be of use in clinical management, preoperative planning, and in the evaluation of the degree of degeneration at the common extensor tendon insertion.
PURPOSE: The aim of this study was to compare various pulse-sequences employing the spine array coil while considering the different infiltration patterns in multiple myeloma, in order to develop a fast and cost effective screening method. MATERIALS AND METHODS: In a prospective study, 50 patients with histologically proven multiple myeloma were examined with the following standardised sequences: T1-weighted SE, T2-weighted FSE, opposed phase GRE, FSE STIR, T1-weighted SE post gadopentate dimeglumine without and with fat saturation. The images were evaluated in a ROC analysis by three radiologists in consensus with a 5-grade scale separatively for diffuse and focal involvement. The gold standard was bone marrow histology in cases of diffuse infiltration and the combination of all sequences with the staging system according to Durie and Salmon. RESULTS: For focal bone marrow involvement the area under curve was greatest for FSE STIR sequences, in cases of diffuse infiltration the area under curve was superior for unenhanced T1-w SE-Sequenz images. The sensitivity can be increased by contrast material application and signal intensity measurements. A combined focal and diffuse infiltration and a "salt and pepper" pattern can be diagnosed with the combination of T1-w SE-Sequenz and FSE STIR sequences. CONCLUSION: With T1-weighted SE-Sequenz sequences pre- and post-contrast and FSE STIR all therapeutical relevant infiltration patterns of plasmocytoma can be identified and bone marrow screening of the spine can be carried out with an acquisition time of 5.58 minutes.