Evaluation of extensive inflammatory conditions of the bowel using three-dimensional CT cinematic rendering: focus on inflammatory bowel disease

Inflammatory conditions that affect long segments of bowel and/or the mesentery and mesenteric vasculature are a common cause of emergency department visits and evaluation by cross-sectional imaging. Inflammatory bowel disease, specifically Crohn disease and ulcerative colitis, can be unsuspected at presentation and may only be eventually diagnosed based on initial imaging findings. Traditional 2D axial reconstructions and multi-planar reformations can be limited in their ability to globally assess the extent of disease. 3D methods such as volume rendering (VR) are often used as adjunctive means of visualizing the pathology in such patients. Recently, a novel technique known as cinematic rendering (CR) has emerged, utilizing advanced lighting models and ray tracing to simulate photon interactions with tissues, resulting in realistic shadows and enhanced surface detail compared to VR. Generating CR images from select presets takes an experienced radiologist approximately 5 min, meaning that the technique can be incorporated into meaningful emergency department workflows. Given the apparent advantages of CR, we highlight its application in a series of cases in which patients had inflammatory conditions that affected long segments of bowel and/or involved the mesentery, particularly those patients with inflammatory bowel disease, but also including patients with mesenteric venous thrombosis and lymphedema. Those conditions included inflammatory bowel disease, mesenteric venous thrombosis, and bowel lymphedema. We present examples of those conditions in this pictorial essay and describe the potential of CR to visualize key findings. As CR exhibits possible advantages, further studies are warranted to support its broader clinical adoption and assess its efficacy in diagnosing and guiding managing of inflammatory conditions in emergency settings.