Giant Cerebral Aneurysms: Comparing CTA, MRA, and Digital Subtraction Angiography Assessments

Abstract

BACKGROUND AND PURPOSE: Comprehensive imaging characterization of the morphology and luminal patency of cerebral aneurysms are cornerstones of their successful treatment and subsequent appropriate management. Giant cerebral aneurysms (GCAs), a distinct subgroup of aneurysms, are defined by large size (ࣙ 25 mm in greatest diameter), complex blood flow dynamics, and a high risk of rupture. The purpose of this study is to explore compare multiple imaging modalities in the assessment of GCAs. METHODS: This study retrospectively evaluated CT angiography (CTA), 3D time-of-flight (TOF) MR angiography (MRA), contrastenhanced MRA (CEMRA), and digital subtraction angiography (DSA) in characterizing GCAs in 21 patients. RESULTS: Aneurysm size ranged from 26 to 58 mm (mean 31.3 ± 12.2) and 18/21 (85.7%) had intraluminal thrombus. No significant difference was found between the aneurysmal sizes of any two modalities regarding comparisons of CTA, 3D TOFMRA, and CEMRA. However, there were significant differences in the aneurysmal patency visibility grade between CTA versus TOFMRA and CTA versus CEMRA. Moreover, the patent luminal size measured on CTA was significantly larger than DSA. CONCLUSIONS: CTA, 3D TOFMRA, and CEMRA are equivalent in the delineation of size of GCAs. Nevertheless, 3D TOFMRA and CEMRA seem to be inferior to CTA in demonstrating luminal size/patency, likely because of the signal loss resulting from the presence of intraluminal thrombus and flow turbulence. Moreover, CTA is superior to DSA in determining lumen patency in GCAs, probably due to CTA's multipass-related luminal enhancement while DSA general fills the lesion via the first pass of enhancement or soon thereafter. In addition, CTA may also better demonstrate intraluminal thrombus, adjacent anatomical structures, and calcified rims.

Intracranial Aneurysms Mimicking Third Ventricular and adjoining parts Masses Associated with Obstructive Hydrocephalus: Diagnosis and Treatment

“…Several studies have determined that CTA can replace DSA for aneurysm diagnosis, 28-30 especially for giant aneurysms. 31,32 We used CTA to diagnose giant aneurysms mimicking intraventricular tumors and used it as the main index of follow-up after aneurysm coil occlusion procedures, and the results of CTA are precise and stable. Aneurysms presenting as third ventricular masses have been studied in several limited cases between 1979 and 2020 because of the infrequency of this disease.…”

“…CT angiography is increasingly becoming a diagnostic tool for vessel pathology. 31 Aneurysms larger than 3 or 4 mm can be recognized with CTA. Teksam et al reported that CTA missed only seven out of 106 cases, and of these, only two were larger than 4 mm.…”

Noninvasive Angiographic Results of Clipped or Coiled Intracranial Aneurysms: An Inter- and Intraobserver Reliability Study

“…11,29 CTA of clipped aneurysms has generally not been as accurate compared with conventional angiography, especially for small aneurysms, when multiple clips were used, on small parent vessels, or when the aneurysm was in the vicinity of bony structures. 12,[30][31][32] These same technical limitations may explain the trend toward lower agreement for clipped aneurysm subgroups assessed by CTA compared with coiled aneurysms assessed by MRA.…”

Risk Factors and Distribution Characteristics of Intracranial and Intracranial Artery Stenosis in Young Sufferers with Ischemic Stroke

“…If the stenosis is serious and the blood flow speed is slow, thrombosis may be formed in the blood vessels. However, digital subtraction angiography (DSA) of the whole brain is unified as the “golden gold” for diagnosing the occurrence of AS in young IS sufferers [ 6 , 7 ]. The reason is that DSA can clearly show the distribution site and stenosis degree of AS and provide diagnostic criteria for subsequent therapy.…”