Extent of Signal Hyperintensity on Unenhanced T1-weighted Brain MR Images after More than 35 Administrations of Linear Gadolinium-based Contrast Agents.

Purpose To explore the extent of signal hyperintensity in the brain on unenhanced T1-weighted magnetic resonance (MR) images with increasing gadolinium-based contrast agent (GBCA) doses in patients who received 35 or more linear GBCA administrations. Materials and Methods In this institutional review board-approved HIPAA-compliant retrospective study, picture archiving and communication systems of two tertiary referral hospitals were searched to identify patients who received 35 or more linear GBCA administrations. Unenhanced T1-weighted images of the brain in patients after six, 12, and 24 GBCA administrations and after the final GBCA administration were independently reviewed by three radiologists to identify sites where T1 signal intensity was increasing. Areas identified by all three observers as increasing in T1 signal intensity when compared with baseline images were further analyzed with a quantitative region of interest analysis measuring the rate of signal increase per injection and the total change after 24 linear GBCA administrations relative to reference tissues that did not show T1 shortening. Results Qualitative analysis of 13 patients with 39-59 linear GBCA administrations showed visually detectable T1 shortening in the dentate nucleus (n = 13), globus pallidus (n = 13), substantia nigra (n = 13), posterior thalamus (n = 12), red nucleus (n = 10), colliculi (n = 10), superior cerebellar peduncle (n = 7), caudate nucleus (n = 4), whole thalamus (n = 3), and putamen (n = 2). Quantitative analysis enable confirmation of signal intensity increases on unenhanced T1-weighted images relative to reference tissues in the dentate nucleus (0.53% signal intensity increase per injection, P < .001), globus pallidus (0.23% increase, P = .009), posterior thalamus (0.26% increase, P < .001), substantia nigra (0.25% increase, P = .01), red nucleus (0.25% increase, P = .01), cerebellar peduncle (0.19% increase, P = .001), and colliculi (0.21% increase, P = .02). Conclusion Increased signal intensity on unenhanced T1-weighted images was seen in the posterior thalamus, substantia nigra, red nucleus, cerebellar peduncle, colliculi, dentate nucleus, and globus pallidus. © RSNA, 2016.

Visual Interpretation with Three-Dimensional Annotations (VITA): three-dimensional image interpretation tool for radiological reporting.

This paper introduces a software framework called Visual Interpretation with Three-Dimensional Annotations (VITA) that is able to automatically generate three-dimensional (3D) visual summaries based on radiological annotations made during routine exam reporting. VITA summaries are in the form of rotating 3D volumes where radiological annotations are highlighted to place important clinical observations into a 3D context. The rendered volume is produced as a Digital Imaging and Communications in Medicine (DICOM) object and is automatically added to the study for archival in Picture Archiving and Communication System (PACS). In addition, a video summary (e.g., MPEG4) can be generated for sharing with patients and for situations where DICOM viewers are not readily available to referring physicians. The current version of VITA is compatible with ClearCanvas; however, VITA can work with any PACS workstation that has a structured annotation implementation (e.g., Extendible Markup Language, Health Level 7, Annotation and Image Markup) and is able to seamlessly integrate into the existing reporting workflow. In a survey with referring physicians, the vast majority strongly agreed that 3D visual summaries improve the communication of the radiologists' reports and aid communication with patients.

Duodenogastric reflux in a hiatal hernia seen as retrocardiac activity on 99mTc-tetrofosmin cardiac SPECT raw-data images.

We present a patient with a large hiatal hernia resulting in duodenogastric reflux that was seen as abnormal activity below and behind the heart (retrocardiac) on SPECT images and on (99m)Tc-tetrofosmin cardiac SPECT raw-data projection images. Incidental findings such as extra- and retrocardiac activity in the thorax and abdomen should be included on all comprehensive cardiac SPECT reports.