Carotid and vertebral injury study (CAVIS) technique for characterization of blunt traumatic aneurysms with reliability assessment

Endovascular treatment of blunt injury of the extracranial internal carotid artery: the prospect and dilemma

The extracranial internal carotid artery (ICA) refers to the anatomic location that reaches from the common carotid artery proximally to the skull base distally. The extracranial ICA belongs to the C1 segment of the Bouthillier classification and is at considerable risk for injury. Currently, the understanding of endovascular treatment (EVT) for blunt injury of the extracranial ICA is limited, and a comprehensive review is therefore important. In this review, we found that extracranial ICA blunt injury should be identified in patients presenting after blunt trauma, including classical dissection, pseudoaneurysm, and stenosis/occlusion. Computed tomography angiography (CTA) is the first-line method for screening for extracranial ICA blunt injury, although digital subtraction angiography (DSA) remains the "gold standard" in imaging. Antithrombotic treatment is effective for stroke prevention. However, routine EVT in the form of stenting should be reserved for patients with prolonged neurological symptoms from arterial stenosis or considerably enlarged pseudoaneurysm. Endovascular repair is now emerging as a favored therapeutic option given its demonstrated safety and positive clinical and radiographic outcomes.

Wall enhancement of intracranial saccular and fusiform aneurysms may differ in intensity and extension: a pilot study using 7-T high-resolution black-blood MRI

PURPOSE

To evaluate and compare wall enhancement patterns in saccular and fusiform intracranial aneurysms using high-resolution black-blood MRI at 7 T.

METHODS

Thirty-one patients with 32 unruptured intracranial aneurysms (21 saccular and 11 fusiform) underwent 7-T black-blood MRI. Aneurysm wall enhancement (AWE) was categorized as follows: no wall enhancement (NWE), focal wall enhancement (FWE), and uniform wall enhancement (UWE). The degree of enhancement was scored as follows: 0 (no enhancement), 1 (signal intensity (SI) of the aneurysm wall less than that of the pituitary infundibulum), and 2 (equal to that of the pituitary infundibulum). The chi-squared test was used to compare the AWE pattern and degree between saccular and fusiform aneurysms.

RESULTS

In saccular aneurysms, 12/21 (57%) enhanced. Of these, 9 showed FWE (5 grade 1 and 4 grade 2), and 3 showed UWE (2 grade 1 and 1 grade 2). In fusiform aneurysms, 11/11 (100%) enhanced. Of these, 1 showed FWE and 10 showed UWE. All fusiform aneurysms had grade-2 enhancement. Fusiform aneurysms had more extensive and higher SI AWE than saccular aneurysms (p < 0.01) despite having a similar size (6.9 ± 3.0 mm vs. 8.0 ± 2.9, p = 0.23). For saccular aneurysm, larger aneurysm size was correlated with higher degree of enhancement with Pearson's r = 0.64 (p = 0.002).

CONCLUSION

Intracranial fusiform aneurysms had enhancement of higher SI and that covered a more extensive area than saccular aneurysms, which might indicate differences in vessel wall pathology.

KEY POINTS

• Intracranial aneurysm wall enhancement can be reliably characterized by 7-T black-blood MRI. • AWE in intracranial fusiform aneurysms presents over a larger surface area and with greater signal intensity as compared with that in saccular aneurysms, which might indicate differences in pathology. • Stronger signal intensity of AWE correlates with the aneurysm size in saccular aneurysms.

Optical coherence tomography of traumatic aneurysms of the internal carotid artery: report of 2 cases

The pathophysiology of extracranial traumatic aneurysm formation has not been fully elucidated. Intraarterial optical coherence tomography (OCT), an imaging modality capable of micrometer cross-sectional resolution, was used to evaluate patients presenting with saccular traumatic aneurysms of the internal carotid artery (ICA). Two consecutive trauma patients diagnosed with saccular traumatic aneurysms of the cervical ICA, per the institutional screening protocol for traumatic cerebrovascular injury, underwent digital subtraction angiography (DSA) with OCT. Optical coherence tomography demonstrated disruption of the intima with preservation and stretching of the more peripheral layers. In 1 patient the traumatic aneurysm was associated with thrombus formation and a separate, more proximal dissection not visible on CT angiography (CTA) or DSA. Imaging with OCT indicates that saccular traumatic aneurysms may develop from disruption of the intima with at least partial preservation of the media and adventitia. This provides in vivo evidence that saccular traumatic aneurysms result from a partial arterial wall tear rather than complete disruption. Interestingly, OCT was also able to detect arterial injury and thrombi not visible on CTA or DSA.