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Magnetic resonance imaging (MRI) is the most sensitive technique for detecting inflammatory demyelinating lesions in multiple sclerosis (MS) and plays a crucial role in diagnosis and monitoring treatment effectiveness, and for predicting the disease course. In clinical practice, detection of MS lesions is mainly based on T2-weighted and contrast-enhanced T1-weighted sequences. Contrast-enhancing lesions (CEL) on T1-weighted sequences are related to (sub)acute inflammation, while new or enlarging T2 lesions reflect the permanent footprint from a previous acute inflammatory demyelinating event. These two types of MRI features provide redundant information, at least in regular monitoring of the disease. Due to the concern of gadolinium deposition after repetitive injections of gadolinium-based contrast agents (GBCAs), scientific organizations and regulatory agencies in Europe and North America have proposed that these contrast agents should be administered only if clinically necessary. In this article, we provide data on the mode of action of GBCAs in MS, the indications of the use of these agents in clinical practice, their value in MS for diagnostic, prognostic, and monitoring purposes, and their use in specific populations (children, pregnant women, and breast-feeders). We discuss imaging strategies that achieve the highest sensitivity for detecting CELs in compliance with the safety regulations established by different regulatory agencies. Finally, we will briefly discuss some alternatives to the use of GBCA for detecting blood–brain barrier disruption in MS lesions. Clinical relevance statement: Although use of GBCA at diagnostic workup of suspected MS is highly valuable for diagnostic and prognostic purposes, their use in routine monitoring is not mandatory and must be reduced, as detection of disease activity can be based on the identification of new or enlarging lesions on T2-weighted images. Key Points: • Both the EMA and the FDA state that the use of GBCA in medicine should be restricted to clinical scenarios in which the additional information offered by the contrast agent is required. • The use of GBCA is generally recommended in the diagnostic workup in subjects with suspected MS and is generally not necessary for routine monitoring in clinical practice. • Alternative MRI-based approaches for detecting acute focal inflammatory MS lesions are not yet ready to be used in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: To assess the additional value of multiplanar reformations (MPR) in comparison with axial images alone for location of the transition zone in CT of mechanical small-bowel obstruction (SBO). Materials and Methods: Sixty-nine consecutive patients with mechanical SBO underwent 16-slice multi detector row CT (MDCT). The gold standard for the precise location of the transition zone was established by two experienced abdominal radiologists, unblinded to clinical and surgical reports, reviewing all CT examinations. On a workstation, two blinded readers independently located the transition zone using first axial slices alone and then 1 month later MPR (axial, coronal, sagittal and oblique views) according to a three-point confidence scale. Diagnostic accuracy and mean confidence score were evaluated for both the transverse and multiplanar data sets. Results: Accuracy of transition zone location for reader 1 and reader 2 was 86% and 84% with axial slices alone, and by using MPR 93% (significant: P = 0.03) and 90% (not significant: P = 0.08), respectively. Mean confidence score was significantly increased for both readers using MPR: 0.3 higher (P = 0.0001) and 0.37 higher (P = 0.0001) respectively. Conclusion: MPR can increase both accuracy and confidence in the location of the transition zone in CT of SBO. [ABSTRACT FROM AUTHOR]