The value of narrow CT window settings in the recognition of subtle acute aortic intramural haematoma

Four patients with acute aortic intramural haematoma are presented. In all patients the typical crescentic hyperdense rim within the aortic wall was not obvious on unenhanced CT when reviewed on standard mediastinal windows, but the hyperdense crescentic rim was well seen on narrow window settings. The findings suggest that all patients with a typical clinical presentation of acute thoracic aortic dissection who do not have a classical dissection on contrast-enhanced CT or a hyperdense intramural haematoma on standard mediastinal settings, should have the non-contrast scans reviewed on narrow window settings. Copyright (1999) Blackwell Science Pty Ltd