Atypical presentation of an impending thoracoabdominal aortic aneurysm rupture: The hyperattenuating crescent sign as a life-saving imaging feature

An aortic aneurysm is defined as a focal dilatation of the aortic diameter, often remaining clinically silent until the onset of potentially fatal complications. Detection at the prerupture stage represents a major diagnostic challenge for both clinicians and radiologists, yet it can be life-saving. We report the case of a 55-year-old female patient who presented with persistent epigastric pain unresponsive to medical treatment. CT angiography revealed an approximately 58-mm symptomatic thoracoabdominal aortic aneurysm with a hyperattenuating crescent sign concerning for impending rupture, highlighting the pivotal role of vascular imaging in the early diagnosis of this silent but life-threatening condition.