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Objective: To determine the dosage of gadobenate dimeglumine (Gd-BOPTA) necessary for MRI of rheumatoid arthritis of the wrist., Design and Patients: Seven wrists inflamed with rheumatoid arthritis were imaged using a dedicated 0.2-T MR unit. Four cumulative dosages of 0.0125, 0.025, 0.05 and 0.1 mmol/kg body weight (BW) Gd-BOPTA were tested. Three-dimensional T1-weighted gradient-recalled echo sequences (GRE; TR: 100 ms, TE: 18 ms, flip angle 90 degrees , 4:55 min) were acquired prior to an intravenous injection and after each additional dosage of Gd-BOPTA. Relative enhancement, signal-difference-to-noise ratios (SDNRs) and the size of the inflamed tissue were quantified. Three radiologists independently evaluated the image quality, the size and the contrast of the enhancing tissue., Results: The readers agreed on a dose of 0.05 mmol/kg BW as satisfactory for the evaluation of the size of the inflammatory tissue and for determination of bone involvement (kappa = 0.9, P < 0.001). Highly inflammatory pannus was depicted with adequate image contrast using 0.025 mmol/kg BW Gd-BOPTA. According to the SDNR and relative enhancement findings, a dose of 0.05 mmol/kg BW suffices for both off-center and centered regions of tissue inflammation (t-test, P < 0.05)., Conclusion: Gadolinium-BOPTA is an alternative contrast agent for MRI of rheumatoid disease. This study shows that a dose of 0.05 mmol/kg BW suffices at low field strength.

Purpose: To determine if, in a patient with an endometrial cancer, in addition to the knowledge of tumor grade, preoperative magnetic resonance (MR) imaging findings contribute to treatment stratification and specialist referral., Materials and Methods: By using a MEDLINE literature search and institutional pathology reports, pretest probabilities for myometrial invasion were correlated with tumor grade. Likelihood ratios (LRs) were obtained through summary receiver operating characteristics., Results: The mean pretest probabilities of deep myometrial invasion were derived from seven articles (1,875 patients) and from 125 institutional pathology reports. LRs for the prediction of myometrial invasion with contrast-enhanced MR imaging were derived from nine studies (742 patients); positive and negative LRs were 10.11 and 0.1, respectively. The mean weighted pretest probabilities of deep myometrial invasion in patients with tumor grades 1, 2, or 3 were 13%, 35%, or 54%, respectively. Posttest probabilities of deep myometrial invasion for grades 1, 2, or 3 increased to 60%, 84%, or 92%, respectively, for positive and decreased to 1%, 5%, or 10%, respectively, for negative MR imaging findings., Conclusion: Use of contrast-enhanced MR imaging significantly affects the posttest probability of deep myometrial invasion in patients with all grades of endometrial cancer and could be used to select patients for specialist referral.

Purpose: To give an overview of various diagnostic techniques and indications for phlebography in different parts of the body., Methods: Procedures of conventional phlebography of the lower and upper extremity and cavography are described and their indications in comparison to alternative techniques are discussed. The literature is reviewed with regard to specific advantages and disadvantages of the different methods., Results: Conventional phlebography with iodine contrast media is still considered to be the gold standard in many regards. The diagnosis of acute and chronic thrombotic disease, venous vascular occlusions, hemodynamic malfunctions and anatomic variants of the venous system can readily be established with contrast phlebography., Discussion: Main disadvantages of contrast studies of the venous system are radiation exposure and adverse effects of contrast media. Non-invasive methods such as ultrasound and MR-phlebography are becoming more and more popular and may replace venography. Other techniques such as CT-phlebography and the use of CO2 as contrast medium are under investigation. The latter can be indicated in the case of contraindications against iodine contrast media., Conclusion: When choosing diagnostic methods for the venous system, their sensitivity and specificity for specific diagnoses and vascular territories have to be balanced against the risks and disadvantages.

The purpose of the study was to evaluate observer performance in the detection of pneumothorax with cesium iodide and amorphous silicon flat-panel detector radiography (CsI/a-Si FDR) presented as 1K and 3K soft-copy images. Forty patients with and 40 patients without pneumothorax diagnosed on previous and subsequent digital storage phosphor radiography (SPR, gold standard) had follow-up chest radiographs with CsI/a-Si FDR. Four observers confirmed or excluded the diagnosis of pneumothorax according to a five-point scale first on the 1K soft-copy image and then with help of 3K zoom function (1K monitor). Receiver operating characteristic (ROC) analysis was performed for each modality (1K and 3K). The area under the curve (AUC) values for each observer were 0.7815, 0.7779, 0.7946 and 0.7066 with 1K-matrix soft copies and 0.8123, 0.7997, 0.8078 and 0.7522 with 3K zoom. Overall detection of pneumothorax was better with 3K zoom. Differences between the two display methods were not statistically significant in 3 of 4 observers (p-values between 0.13 and 0.44; observer 4: p = 0.02). The detection of pneumothorax with 3K zoom is better than with 1K soft copy but not at a statistically significant level. Differences between both display methods may be subtle. Still, our results indicate that 3K zoom should be employed in clinical practice. [ABSTRACT FROM AUTHOR]

Die konventionelle Phlebographie mit jodhaltigen Kontrastmitteln gilt in vieler Hinsicht noch als Goldstandard. Die Diagnose von akuten und chronischen Thrombosen, Gefäßverschlüssen, hämodynamischen Dysfunktionen oder angeborenen Anomalien im Venensystem gehört zu den Aufgaben von Phlebographie mit Kontrastmittel. Sie kann in nahezu allen venösen Gefäßabschnitten des Körpers eingesetzt werden. Nachteile sind die Exposition mit ionisierenden Strahlen und die mit jodhaltigen Kontrastmitteln verbundenen Nebenwirkungen. Nichtinvasive Verfahren wie der Ultraschall und die MR-Phlebographie gewinnen zunehmend an Bedeutung und können bei bestimmten Fragestellungen die Phlebographie ersetzen. Alternative Verfahren wie die CT-Phlebographie oder die Verwendung von CO2 als Kontrastmittel sind eher die Ausnahme. Letztere kommt bei Kontraindikationen gegen Kontrastmittelgabe zum Einsatz. Bei der Auswahl der Untersuchungsverfahren muß deren diagnostische Aussagekraft einerseits und mögliche Risiken und Limitationen andererseits berücksichtigt werden. Purpose: To give an overview of various diagnostic techniques and indications for phlebography in different parts of the body. Methods: Procedures of conventional phlebography of the lower and upper extremity and cavography are described and their indications in comparison to alternative techniques are discussed. The literature is reviewed with regard to specific advantages and disadvantages of the different methods. Results: Conventional phlebography with iodine contrast media is still considered to be the gold standard in many regards. The diagnosis of acute and chronic thrombotic disease, venous vascular occlusions, hemodynamic malfunctions and anatomic variants of the venous system can readily be established with contrast phlebography. Discussion: Main disadvantages of contrast studies of the venous system are radiation exposure and adverse effects of contrast media. Non-invasive methods such as ultrasound and MR-phlebography are becoming more and more popular and may replace venography. Other techniques such as CT-phlebography and the use of CO2 as contrast medium are under investigation. The latter can be indicated in the case of contraindications against iodine contrast media. Conclusion: When choosing diagnostic methods for the venous system, their sensitivity and specificity for specific diagnoses and vascular territories have to be balanced against the risks and disadvantages. [ABSTRACT FROM AUTHOR]