case_images: PMC8248007_01
case_images: Cerebral angiogram of the left ICA, showing the 18 mm intracavernous fusiform aneurysm.
case_images: SNI-12-225-g001.jpg
case_images: PMC8248007_01_SNI-12-225-g001.jpg
case_images: F1
case_images: This unruptured, partially thrombosed aneurysm was confirmed on diagnostic cerebral angiography, [Figure 1].
case_images: PMC8248007_02
case_images: PMC8248007_03
case_images: Conventional unenhanced CT showing diffuse subarachnoid hyperdensity of the left cerebral hemisphere.
case_images: SNI-12-225-g002.jpg
case_images: PMC8248007_03_SNI-12-225-g002.jpg
case_images: F2
case_images: CT, which is standard first-line radiographic assessment to assess for a postoperative complication. CT showed diffuse subarachnoid hyperdensity of the left cerebral hemisphere, shown in [Figure 2].
case_images: (a) Images from dual-energy CT. Conventional CT images again illustrating diffuse subarachnoid hyperdensity of the left cerebral hemisphere. (b) Iodine map, illustrating the ability to isolate only iodine contrast material as this has a single density that differs to that of hemorrhage. (c) Virtual nonenhanced image, where iodine contrast material identified on iodine map has been removed. Therefore, as showing no residual hyperdensity, this illustrates that it was all contrast material extravasation.
case_images: SNI-12-225-g003.jpg
case_images: PMC8248007_03_SNI-12-225-g003.jpg
case_images: F3
case_images: The use of dual-energy CT is illustrated in [Figure 3]. [Figure 3a] shows conventional CT images, whereas [Figure 3b] illustrates the iodine map. Iodine contrast can then be removed to create a virtual nonenhanced image, shown in [Figure 3c].
case_images: Conventional unenhanced CT performed 24 h post procedure showing resolution of hyperdensity.
case_images: SNI-12-225-g004.jpg
case_images: PMC8248007_03_SNI-12-225-g004.jpg
case_images: F4
case_images: Follow-up conventional CT imaging shown in [Figure 4] was performed the following day and confirmed this diagnosis, as all hyperdensity had resolved, in keeping with contrast medium extravasation.
case_images: PMC8248007_04
case_images: PMC8248007_05