No abstract

On ferumoxtran-10-enhanced MR lymphangiography, contrast-enhanced images alone may suffice for lymph node characterization. However, a certain level of interpretation experience may be required before contrast-enhanced images can be used alone.

Detection of local or regional metastases to lymph nodes is clinically important in virtually any type of primary tumor. Current imaging techniques rely heavily on the size criterion for characterization of nodal disease. However, size can be an ineffective parameter for diagnosis of tumor spread to lymph nodes. Magnetic resonance (MR) imaging performed before and after administration of ferumoxtran-10 is a promising technique for characterization of lymph nodes in patients with various primary tumors. Normal homogeneous uptake of ferumoxtran-10 in nonmetastatic nodes shortens the T2 and T2*, turning these nodes dark, whereas malignant nodes lack uptake and remain hyperintense. To optimize acquisition strategies, the following factors should be considered: the timing of contrast material-enhanced imaging, the section thickness, the imaging plane, and the imaging parameters for T2*-weighted sequences. In addition, MR imaging with ferumoxtran-10 allows presurgical mapping of lymph nodes and quantitative estimation of T2*.

PurposeMagnetic resonance imaging (MRI) is the most current diagnostic imaging procedure for suspected ACL injuries. It is an accurate, highly sensitive and specific tool for the diagnosis of ACL tears, graft tears and associated injuries. However, it can also be used for various other aspects of anatomic ACL reconstruction.MethodsSpecial sequences as the oblique sagittal plane should be obtained from a parallel line to the lateral epicondyle, ensuring a proper visualization of both bundles of the ACL. Another special set of images, the oblique-coronal sequence, allows for the ACL long-axis evaluation. The coronal-oblique sequence increases the sensitivity and specificity of diagnosing isolated AM or PL bundle injuries and also helps to visualize the proximal insertion of the bundles for haemorrhage and rupture.ResultsQuantitative measurements can be taken from a proper MRI protocol, so as to determine the rupture pattern; measure insertion site size, inclination angle and autograft size; and evaluate for post-operative complications. These parameters help surgeons to objectively decide for a better graft and technique for an individualized approach and to evaluate the anatomic placement of the graft.ConclusionsMRI can be used in different ways, serving as a very valuable tool in anatomic ACL reconstruction. Special protocols can provide accurate visualization of the double-bundle anatomy. Objective parameters to aid in pre-operative decisions and graft’s anatomic placement evaluation can be also extracted from the MR images.