Imaging of giant cerebral aneurysms

Comparative Study of the Diagnostic Value of Zero-Echo-Time Magnetic Resonance Angiography With Time-of-Flight Magnetic Resonance Angiography for Intracranial Aneurysm

OBJECTIVE

Intracranial aneurysm (IAN) is a class of cerebrovascular diseases with a serious threat to patients, and an accurate diagnosis of IAN is very important for both selection of the appropriate therapy and prediction of the prognosis. This study aimed to evaluate the diagnostic values of zero-echo-time magnetic resonance angiography (ZTE-MRA) and time-of-flight magnetic resonance angiography (TOF-MRA) in patients with IAN.

METHODS

Digital subtraction angiography, ZTE-MRA, and TOF-MRA were performed in 18 patients diagnosed with IAN. The images of ZTE-MRA and TOF-MRA were compared for image quality, qualitative diagnosis, detailed diagnosis, number of thrombi, and residual aneurysm lumen, with digital subtraction angiography as the reference.

RESULTS

Zero-echo-time MRA and TOF-MRA did not show a significant difference in image quality or detailed information (including aneurysm size, growth direction, and angle with the aneurysm-carrying vessel) ( P > 0.05). However, ZTE-MRA showed advantages over TOF-MRA in terms of qualitative diagnosis (sensitivity and specificity), intra-aneurismal thrombus detection, and residual aneurysm lumen detection after embolization ( P < 0.05).

CONCLUSIONS

Compared with TOF-MRA, ZTE-MRA showed greater diagnostic value for IAN patients in terms of qualitative diagnosis, as well as the detection of intra-aneurysm thrombi and residual aneurysm lumen after embolization.

A Supplemental Technique for Preoperative Evaluation of Giant Intracranial Aneurysm

BACKGROUND

 Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in giant intracranial aneurysms (GIAs). In this study, we aimed to reconstruct the circulating and noncirculating parts of GIAs with the time-of-flight (TOF) and motion-sensitized driven-equilibrium (MSDE) sequences with 3D Slicer to reveal an integrated presentation of GIAs, compare its accuracy, and validate the usefulness for preoperative planning.

MATERIAL AND METHODS

 Patients with GIAs who were treated with microsurgery in our department were included in this study. Both the TOF and MSDE sequence data for each patient were loaded into 3D Slicer for reconstruction and segmentation. The parameters measured by 3D Slicer were compared with those measured by DSA.

RESULTS

 The mean diameter for all GIAs was 28.7 ± 1.5 mm (range, 25.9-31.9 mm). The mean diameter for all GIAs measured by DSA and 3D Slicer was 24.46 ± 5.25 and 28.66 ± 1.48 mm, respectively (t = 4.948, p < 0.01). When only the nonthrombotic GIAs were included, the mean diameter measured by DSA and 3D Slicer was 28.69 ± 2.03 and 28.97 ± 1.79 mm, respectively (t = 1.023, p = 0.323). The mean aneurysmal volume was 8,292.6 ± 1,175.1 mm³ and the mean thrombotic volume was 3,590.0 ± 1,003.7 mm³.

CONCLUSION

 The MSDE sequence brings diagnostic benefits as a comparison to other MRI sequences. Reconstruction of GIAs with 3D Slicer is a low-cost, dependable, and useful supplemental technique for surgical planning.

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

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), contrast-enhanced 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.

Giant serpentine aneurysm of the internal cerebral artery and mandibular aneurysm: a case report

BACKGROUND

Giant serpentine aneurysms (GSA) originate from saccular or spindle aneurysm, dissimilar from dissected aneurysm, that are defined as partially thrombosed giant aneurysms with tortuous internal vascular channel. The clinical and neuroradiologic characteristics are clarified and the mechanism of formation and the efficacy of double stent implantation in GSA are discussed.

CASE PRESENTATION

An 18-year-old man presented himself with a GSA arising from the internal cerebral artery (ICA). In addition, a mandibular aneurysm (MA) arose from the external cerebral artery (ECA). Success was achieved in treating GSA through endovascular treatment with double stents implanted in the parent artery, which were LEO stent and Tubridge flow diverter. After 1 year of follow-up, three-dimensional reconstruction of blood vessels revealed the disappearance of the serpentine access of GSA, which was found to be replaced with a roughly normal vascular structure.

CONCLUSIONS

Double stent implantation has provided a feasible treatment option for giant serpentine internal carotid aneurysms and eliminated the possibility of causing collateral circulation occlusion. Therefore, it represents a simple and suitable treatment method for anatomical structure and operation.

Giant Serpentine Middle Cerebral Artery Aneurysm

Giant serpentine aneurysms are rare entity, which have unique presentations and distinct angiographic features, with poor prognosis if not treated. In this paper, a patient with a giant serpentine aneurysm originated from right middle cerebral artery was reported. A 38-year-old woman suffered from progressively headache and vision declined. The computed tomography and magnetic resonance image revealed a partially calcified, large mass (approximately 80 × 70 × 60 mm sized) in the right frontal-temple lobe. On computed tomography angiography, an unruptured, giant, partially thrombosed, serpentine aneurysm was confirmed. After treatment by craniotomy, the patient was rehabilitation. Operation is an effective method for the treatment of giant serpentine aneurysms. In addition, cerebral angiography and balloon test occlusion are the crucial way of preoperative assessment.