bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epiphyseal bone-marrow abnormalities and restitution in legg-calvé-perthes disease
Authors: Hochbergs P. , Eckervall G. , Wingstrand H. , Egund N. , Jonsson K. 
Published: January 2010

Purpose: By means of MR imaging, to determine signal abnormalities in the femoral epiphysis; to determine their location, extent and restitution over time; and to correlate these findings to the Catterall radiological classification. Material and Methods: A total of 247 MR images in 86 patients (101 hips) with Legg-CalvC-Perthes disease were examined. The MR images were taken in the coronal plane, and the images through the center of the femoral head were used for this study. Results: T1-weighted images proved as good as T2-weighted images for the MR evaluation of the extent of the necrosis. In almost every case, the central-cranial part of the epiphysis showed a low initial signal. In Catterall group I, the medial part was never involved. In Catterall III and IV, almost the entire epiphysis showed signal changes. In the period 3–6 years after diagnosis, we still found signal changes in the epiphysis in some hips but there was no correlation with the Catterall classification. After 6 years, the epiphysis showed normal signal intensity in MR imaging. In T1-weighted images, Gd-enhancement occurred in the peripheral regions in the early stages of the disease. The central part of the epiphysis became more enhanced over time and peaked in the period 1–3 years after diagnosis. Conclusion: MR is a valuable modality for monitoring changes in the femoral epiphysis. We propose a new classification of the extent and pattern of epiphyseal bone-marrow abnormalities based on the 4 zones most commonly observed in MR imaging.
Ct of the sacroiliac joints
Authors: Damilakis J. , Prassopoulos P. , Perisinakis K. , Faflia C. , Gourtsoyiannis N. 
Published: January 2010

Purpose: The aim was to select an optimal technique for low-dose high-resolution CT of the sacroiliac joints (SJ). Material and Methods: Dose measurements were performed on a Rando anthropomorphic phantom using thermoluminescence dosimeters for 4 CT protocols and 2 conventional radiography protocols used for SJ evaluation. Six available reconstruction algorithms were tested on CT protocols using 285–665 mAs and 120 or 130 kVp settings and noncontiguous 1.5-mm-thin sections with 3.5-mm intervals. Settings with optimum performance on phantom tests were also applied in a series of 10 patients with SJ arthropathies. Results: A CT protocol using 120 kVp/175 mA2.9 s/1.5-mm slice thicknessb-mm table increment implied the lower radiation dose among all examination protocols tested and provided high image quality of the SJ. A reconstruction algorithm yielding images of improved spatial resolution with acceptable noise was selected. Conclusion: A high spatial frequency reconstruction algorithm, and 120 kVp and 508 mAs were considered optimal for a low-dose CT examination of the SJ that employed narrow (1.5 mm) slice images with interspacing.
MR imaging of meniscal subluxation in the knee
Authors: Breitenseher M. J. , Trattni S. , Dobrocky I. , Kukla C. , Nehrer S. , Steiner E. , Imhof H. 
Published: January 2010

Purpose: The aim of this study was to establish diagnostic criteria for meniscal subluxation, and to determine whether there was any connection between meniscal subluxation and other common meniscal and knee-joint abnormalities. Material and Methods: The normal position of the meniscal body was assessed in 10 asymptomatic volunteers. MR signs of meniscal subluxation were evaluated retrospectively in 60 symptomatic patients with pain in the knee, impaired mobility, and/or joint swelling who had no clear diagnosis after the evaluation of case history, clinical examination, and radiography. The criterion for subluxation of the meniscus was defined as a distance of ≥3 mm between the peripheral border of the meniscus and the edge of the tibial plateau. Results: In the volunteers, the mean distance from the medial meniscus to the edge of the tibial plateau was 0.07 mm, and that from the lateral meniscus was 0 mm. In 55 symptomatic patients without meniscal subluxation, the mean distance from.the meniscus to the edge of the tibial plateau was 0.27 mm. Five patients (8%) had evidence of meniscal subluxation, 4 in the medial meniscus and one in the lateral meniscus. The most commonly associated knee abnormality was joint effusion in 5 knees and osteoarthritis in 2 knees. Conclusion: Meniscal subluxation was not a rare finding with MR imaging in patients with painful knees. Meniscal subluxation was associated with other knee abnormalities such as joint effusion or osteoarthritis.
Kinematic MR imaging of the ankle — initial results with ultra-fast sequence imaging
Authors: Muhle C. , Brinkmann G. , Brossmann J. , Wesner F. , Heller M. 
Published: January 2010

Purpose: In order to evaluate the advantages of ultra-fast MR sequences, kinematic MR imaging studies were performed in 4 patients with osteochondritis dissecans of the talus and in 12 healthy volunteers. Material and Methods: The patients and volunteers were placed inside a custom-made positioning device. Sagittal ultra-fast T2-weighted turbo gradient-echo sequences and HASTE sequences were obtained during active joint motion from dorsiflexion to plantar flexion. Eight sagittal slices were scanned separately to cover this ankle motion. In each slice, 8 to 10 images were obtained in 12-s or 18-s periods. Results: Adequate image quality for analyzing the normal kinematics of the ankle was obtained in all subjects. At surgery, the osteochondral fragment was found to be mobile in 3 of the 4 of the patients. In none of these cases was fragment mobility observed on kinematic MR imaging. No motion of the fragments was observed in the fourth patient, neither at surgery nor on kinematic MR imaging. Conclusion: Ultra-fast MR imaging sequences made it possible to produce kinematic MR imaging studies of active joint motion. The positioning device was useful for guiding joint motion in patients and for obtaining adequate image quality.
Assessment of suspected bone metastases
Authors: Çiray I. , Åström G. , Sundström C. , Hagberg H. , Ahlström H. 
Published: January 2010

Purpose: To evaluate the role of CT with and without clinical information as compared to CT-guided bone biopsy in the assessment of suspected bone metastases. Material and Methods: The study comprised 51 consecutive patients with suspected bone metastases who had undergone CT-guided bone biopsies with an eccentric drill system. CT of the targets, clinical information, and histopathology were scored separately as malignant, uncertain or benign. The results of CT alone and CT in combination with clinical information were compared to the results of histopathology. Results: Histopathology diagnosed 45/51 lesions (88%), 23 as malignant and 22 as benign. CT correctly depicted 17 of these 23 malignant lesions. The remaining 6 malignant lesions were CT-scored as uncertain (n=5) or benign (n=l). CT correctly depicted only 3 of the 22 benign lesions. The remaining 19 benign lesions were CT-scored as malignant (n=2) or uncertain (n=17). When uncertain CT scores were combined with clinical scores, the true-positive and true-negative results for malignancy increased from 44% to 82%. Conclusion: In most cases, CT in combination with clinical information gives enough information about the nature — malignant or benign — of a skeletal lesion. In uncertain cases, diagnostic accuracy can be improved by means of CT-guided bone biopsy.
Bone-marrow MR imaging before and after autologous marrow transplantation in lymphoma patients without known bone-marrow involvement
Authors: Lien H. H. , Blomlie V. , Blystad A. K. , Holte H. , Langholm R. , Kvaløy S. 
Published: January 2010

Purpose: To study lumbar bone marrow by means of MR imaging before and after bone-marrow transplantation in lymphoma patients. Particular emphasis was paid to heterogeneity and to focal manifestations, i.e. appearances that could simulate tumor. Material and Methods: Twenty-two patients who were disease-free for a minimum of 30 months after transplantation were studied in 107 MR examinations. Two radiologists visually evaluated coronal T1-weighted and short inversion time inversion-recovery (STIR) images. Results: T1-weighted images demonstrated a more heterogeneous marrow after transplantation than before it. Sharply defined focal low signal intensity areas appeared on this sequence in 5 (23%) of the 22 patients at between 21 and 60 weeks after transplantation. The mean age of these 5 patients was 48.4 years (range 42–54 years). The difference in age between these 5 patients and the remaining 17 patients, who had a mean age of 33.4 years (range 14–51 years), was statistically significant (p < 0.01, Student's t-test, 2-sided test). Conclusion: Sharply defined focal low signal intensity areas may be seen on T1-weighted images of bone marrow in patients who are in complete remission after transplantation, particularly in those aged over 40–45 years.
CT, MR imaging and muscle biopsy in severe crush injury
Authors: Nakanishi K. , Shimamoto S. , Kishi M. , Yoshioka T. , Ishida T. , Tomoda K. , Nakamura H. 
Published: January 2010

Purpose: We reviewed CT and MR findings in crush injuries in muscles and compared them with findings at muscle biopsy. Material and Methods: CT and MR examinations were made of the lower extremities in 6 adult patients whose muscles were crushed in the big earthquake in Kobe, Japan, on 17 January 1995. All CT examinations were performed twice and within 60 days of the earthquake. In 5 of the 6 patients, biopsies were taken of the injured muscle after the CT and MR examinations. Results: At CT investigation, the images in 5 patients showed calcification in the muscles, and the crushed muscle appeared atrophic. In 3 of these 5, the degree of calcification decreased with time. At MR investigation, T1-weighted images of the crushed muscle showed isointensity in 4 of the 6 patients and high intensity in the remaining 2. T2-weighted images of the crushed muscle showed inhomogeneous high intensity in all patients. After Gd injection, all the crushed muscles were enhanced, either slightly or markedly. At muscle biospy, in 5 of the 6 cases, the findings showed calcification in the muscle cells and the total destruction of the normal muscle structure. Conclusion: CT and MR findings in crush injury correlated well with the findings at histopathology.
Role of MR venography in the evaluation of deep venous thrombosis
Authors: Catalano C. , Pavone P. , Laghi A. , Scipioni A. , Fanelli F. , Assael F. G. , Grossi A. , Venosi S. , Passariello R. 
Published: January 2010

Purpose: MR venography has been recommended for the evaluation of deep venous thrombosis. The purpose of our study was to determine the role of MR venography, in particular at the level of the pelvis where other diagnostic modalities show major limitations. Materials and Methods: Forty-three patients with clinical suspicion of deep venous thrombosis were examined by means of pelvic MR venography. In all cases, a 2D-TOF sequence was used with cranial arterial presaturation. In selected cases, i.e. when a small intraluminal filling defect was present, a cine-PC sequence was used in addition in order to exclude the presence of a pulsatility artifact as causing the filling defect. In all cases, contrast venography was also performed and considered to be the standard of reference. Results: MR venography showed 26 patients to be positive for deep venous thrombosis at the pelvic level. These positive results were correct in 25 cases. The analysis of the results provided values of sensitivity and specificity of respectively 100% and 94%, with an overall accuracy of 97.6%. Conclusion: Our results indicate that MR can provide highly accurate images, similar to those of contrast venography, in a noninvasive fashion. It is particularly useful in the pelvic region where the limitations of other imaging modalities are more evident.
Optimising imaging parameters in experimental spiral CT
Authors: Tiitola M. , Vehmas T. , Kivisaari R. P. , Kivisaari L. 
Published: January 2010

Purpose: This in vitro study was conducted to analyse lesion detection and relative radiation exposure in different CT techniques. Material and Methods: We used a plastic phantom (12x8x2 cm) containing holes filled with air or fluid of varying densities to simulate lesions. This was imaged with Siemens Somatom Plus S and GE High Speed Advantage units. We varied table feeds (3 and 6 mm/s in Siemens and 3 and 4.5 mm/s in GE) and increments (2 mm and 4 mm) while keeping collimation at 3 mm. The Smartscan program of GE and the reformatting algorithm of Siemens were also analysed. To evaluate the different methods, the phantom lesions were counted by 3 observers. Radiation exposures associated with each technique were also measured. Results: The images reformatted to a coronal direction were significantly inferior (p < 0.01) to those in other techniques. The use of Smartscan did not influence lesion detection, nor did changes in pitch or increment. Spiral and non-spiral techniques proved to be equal. Radiation exposure was lowest when a greater pitch or the Smartscan program was used. Conclusion: Radiation exposure in CT can be limited without significantly impairing the image quality by using low-dose techniques. Reformatting to a coronal direction should be used with care as it debases the image quality.
Permeability of contrast media through hemodialysis membrane
Authors: Furukawa T. , Ueda J. , Higashino K. , Takahashi S. , Sakaguchi K. , Imai T. 
Published: January 2010

Purpose: To compare the permeability of 10 contrast media (CM) through the hemodialysis membrane. Material and Methods: An experimental model was constructed from clinical hemodialysis equipment. The 10 CM that were used were: diatrizoate, iothalamate, iopami-dol, iohexol, iopromide, ioversol, iomeprol, ioxaglate, iodixanol and iotrolan. They were dissolved into the dialysate. Each solution ran into the blood circuit of the dialyzer at a rate of 200 ml/min and into the dialysate circuit of the dialysis machine at a rate of 500 ml/min. Permeability was expressed as clearance, calculated from the iodine concentration at the afferent and efferent lines of the dialyzer, and from the blood-flow rate. Results: The clearance of all the monomeric CM was superior to that of all the dimeric CM. Values of clearance and molecular weight correlated well. Conclusion: The molecular weight of a contrast medium is the main factor that influences the efficiency of CM removal by hemodialysis.
Ultrasound Diagnosis of Soft-Tissue Tumours in the Hand and Forearm
Authors: Höglund M. 
Published: January 2010

Purpose: The aim of this prospective investigation was to evaluate the accuracy of certain ultrasound characteristics in diagnosing 5 common types of soft-tissue tumour in the hand and forearm. Material and Methods: The study comprised 50 soft-tissue tumours, diagnosed by ultrasonography or histopathology as belonging to one of 5 soft-tissue tumour groups. The reported ultrasound diagnoses and the histopathological results were compared, and their sensitivity was calculated. A statistical model was applied to the prospective material. The first and second diagnostic alternatives were calculated for each specific tumour and for the whole prospective material. In the second part of this study, the prospective material was combined with a retrospective material of 96 tumours from a previous study. The combined material was analysed and the accuracy of the first and second diagnostic alternatives for each tumour and for the whole material was calculated. Results: The sensitivity for the prospective material was 84%. The correct diagnosis predicted by the model for the combined material was 56% for the first alternative and 79% when the second alternative was included. Conclusion: Ultrasonography is useful in the diagnosis of soft-tissue tumours of the hand.
Diagnosis of Hill-Sachs Lesion of the Shoulder
Authors: Pancione L. , Gatti G. , Mecozzi B. 
Published: January 2010

Aim: The Hill-Sachs lesion is a compression fracture caused by impact on the trabeculae of the humeral head during anterior glenohumeral dislocation. The early and accurate identification of patients who risk recurrence of shoulder dislocation requires a suitable screening method. This should be characterized by high sensitivity and specificity, low cost, and repeatability. Material and Methods: The results of ultrasound examination as a screening method were evaluated, the indicator being the identification of the Hill-Sachs lesion. Using ultrasonography and conventional radiological techniques, and double contrast CT (arthro-CT), we studied 60 patients with posttraumatic instability of the shoulder. Results: Against arthro-CT as the true standard, ultrasonography showed a sensitivity of 95.6%, specificity of 92.8%, and diagnostic accuracy of 95%. Conclusion: Ultrasonography is an acceptable screening examination for recurrent scapulohumeral dislocation and should be applied prior to other techniques of investigation such as arthro-CT or MR imaging.
CT Measurement of Anteversion in the Femoral Neck
Authors: Hermann K. L. , Egund N. 
Published: January 2010

Purpose: To evaluate CT methods of measuring anteversion in the femoral neck with respect to measurement accuracy and with respect to the influence exerted by different femoral shaft positions; and to describe a new CT measurement concept that introduces a mathematical adjustment for different femoral shaft positions. The new technique facilitates the taking of measurements in patients who cannot be correctly positioned in traditional methods. Material and Methods: CT examinations of previously measured anteversions in the femoral neck were reviewed in retrospect in 30 patients with fractures of the femoral neck. The position of the femoral shaft was assessed. A reference angle was compared with direct traditional measurements and with measurements adjusted for the actual position of the femoral shaft by means of a 3D mathematical reconstruction. Reproducibility and inter— and intraobserver variability were assessed in 10 cases. Results: All femurs varied in position within the gantry. The mean difference between the direct CT measurement and the adjusted CT measurement compared to the reference angle were -8.8° (range -35.0-16.3°) and -0.1° (range -1.4-1.4°), respectively. For the adjusted CT method, reproducibility and inter- and intraobserver variability were 1.4 intraobserver variability were 1.4, 1.6 intraobserver variability were 1.4 and 1.4° (SD of difference), respectively. Conclusion: CT measurement of femoral anteversion in clinical practice can only be accurate when corrected for variation in the position of the femoral shaft.
Characterization of Sonographically Indeterminate Ovarian Tumors with MR Imaging
Authors: Yamashita Y. , Hatanaka Y. , Torashima M. , Takahashi M. , Miyazaki K. , Okamura H. 
Published: January 2010

Purpose: The goal of this study was to maximize the discrimination between benign and malignant masses in patients with sonographically indeterminate ovarian lesions by means of unenhanced and contrast-enhanced MR imaging, and to develop a computer-assisted diagnosis system. Material and Methods: Findings in precontrast and Gd-DTPA contrast-enhanced MR images of 104 patients with 115 sonographically indeterminate ovarian masses were analyzed, and the results were correlated with histopathological findings. of 115 lesions, 65 were benign (23 cystadenomas, 13 complex cysts, 11 teratomas, 6 fibro-thecomas, 12 others) and 50 were malignant (32 ovarian carcinomas, 7 metastatic tumors of the ovary, 4 carcinomas of the fallopian tubes, 7 others). A logistic regression analysis was performed to discriminate between benign and malignant lesions, and a model of a computer-assisted diagnosis was developed. This model was pro-spectively tested in 75 cases of ovarian tumors found at other institutions. Results: From the univariate analysis, the following parameters were selected as significant for predicting malignancy (p<0.05): a solid or cystic mass with a large solid component or wall thickness greater than 3 mm; complex internal architecture; ascites; and bilaterality. Based on these parameters, a model of a computer-assisted diagnosis system was developed with the logistic regression analysis. To distinguish benign from malignant lesions, the maximum cut-off point was obtained between 0.47 and 0.51. In a prospective application of this model, 87% of the lesions were accurately identified as benign or malignant. Conclusion: Benign and malignant ovarian lesions can be distinguished in most sonographically indeterminate lesions by means of parameters obtained from contrast-enhanced MR imaging.
Magnetic Iron Oxide Particles Coated with Carboxydextran for Parenteral Administration and Liver Contrasting
Authors: Lawaczeck R. , Bauer H. , Frenzel T. , Hasegawa M. , Ito Y. , Kito K. , Miwa N. , Tsutsui H. , Vogler H. , Weinmann H.-J. 
Published: January 2010

Rationale and objectives: To evaluate the physical and pharmacological profiles of SH U555A, a suspension of magnetic iron oxide particles that is designed to enhance the visualization of liver tumors and metastases. Material and Methods: Chemical and physical methods were used to characterize the size and structure of these magnetic iron oxide particles in aqueous solution. The biodistribution and pharmacokinetics of the particles were studied in mice, rats and dogs. The imaging efficacy of the particles was demonstrated by MR imaging in rat liver tumors Results: The SH U555A particles consist of low-molecular-weight carboxydextran-coated iron oxides predominantly of the γ-Fe2O3 form with a hydrodynamic diameter ranging from 57-59 nm and strong T2 relaxivity of 164 liters * mmol−1 * S−1 (water, 0.47 T). In rats the particles exhibited a dose-dependent half-life of between 2 and 3 days in the liver at a dose of 20 μmol Fe/kg and a shorter half-life at lower doses. No major side effects were found. In a rat tumor model the tumor-to-liver contrast was markedly improved after i.v. administration of SH U555A. At a dose of 14 μmol Fe/kg the half-maximal contrast-effect was obtained even in nonoptimized T1-weighted spin-echo images. Conclusion: SH U555A is a superparamagnetic MR contrast agent for i.v. administration and has substantial potential for the demarcation of liver tumors.
Peak Systolic Velocity, Resistance Index and Pulsatility Index
Authors: Mikkonen R. , Kreula J. M. , Virkkunen P. J. 
Published: January 2010

Purpose: To study variation in the process of measuring Doppler ultrasound (US) wave forms. Material and Methods: Eleven radiologists measured peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) from a pre-recorded videotape. The wave forms were taken from the carotid, brachiàl, celiac, and renal interlobar arteries in a healthy volunteer. Each radiologist obtained measurements 10 times from a freely chosen wave form of 10 wave forms (10-beat series) and then a further set of measurements also 10 times from a specific wave form (1-beat series). Results: There was a significant variation in all the PSV, RI and PI values measured, both in the 1-beat series and in the 10-beat series. The greatest variation was seen in the PI values: up to 5.1-fold. Both intraobserver and interobserver reproducibilities were poor. Conclusion: The process of obtaining measurements from an identified wave form is a major source of error in Doppler US studies. Special attention should be paid to this final phase of an examination. We recommend that measurements be obtained from more than one heart beat.