Follow-up Of Intracranial Aneurysms Research Articles

Diagnostic Performance of Pointwise Encoding Time Reduction with Radial Acquisition Subtraction-based MR Angiography in the Follow-up of Intracranial Aneurysms after Clipping.

While follow-up assessment of clipped aneurysms (CAs) using magnetic resonance angiography (MRA) can be challenging due to susceptibility artifacts, anovel MRA sequence pointwise encoding time reduction with radial acquisition (PETRA) subtraction-based MRA, has been developed to reduce these artifacts. The aim of the study was to validate the diagnostic performance of PETRA-MRA by comparing it with digital subtraction angiography (DSA) as areference for follow-up of CAs using a 3T MR scanner. Patients with clipping who underwent both PETRA-MRA and DSA between September 2019 and December 2021 were retrospectively included. Two neuroradiologists independently reviewed with the reconstructed images of PETRA-MRA to assess the visibility of the arteries around the clips and aneurysm recurrence or remnants of CA using a3-point scale. The diagnostic accuracy of PETRA-MRA was evaluated in comparison to DSA. The study included 34patients (28females, mean age 59 ± 9.6years) with 48CAs. The PETRA-MRA allowed visualization of the parent vessels around the clips in 98% of cases, compared to 39% with time-of-flight (TOF) MRA (p < 0.0001). The DSA confirmed 14 (29.2%) residual or recurrent aneurysms. The PETRA-MRA demonstrated a high accuracy, specificity, positive predictive value, and negative predictive value of 99.2%, 100%, 100%, and 97.8%, respectively, while the sensitivity was 66.7%. This retrospective study demonstrates that PETRA-MRA provides excellent visibility of adjacent vessels near clips and has ahigh diagnostic accuracy in detecting aneurysm remnants or recurrences in CAs. Further prospective studies are warranted to establish its utility as areliable alternative for follow-up after clipping.

Abstract 15889: Evaluation of a Novel CTA/DSA-Based Deep-Learning Cerebrovascular Segmentation Method for Cavernous Intracranial Aneurysms

Introduction: CTA is a mainstay diagnostic imaging modality for screening and follow-up of intracranial aneurysms (IAs). One challenge facing neuroradiologists is detection and visualization of IAs on the cavernous internal carotid artery (ICA), which are often obstructed by bony tissue. Such IAs are either missed diagnosed, or must be re-imaged by high-resolution DSA. We sought to evaluate the performance of automated deep learning methods in segmenting cavernous ICA aneurysms from CTA. Methods: In 30 cases, we collected and registered CTA-DSA image pairs to train 2 deep-learning (DL) networks (namely, Brave-Net [BN], and DeepMedic [DM]) for brain vessel segmentation from CTA images of patients with IAs. Segmented DSA was used as the ground truth. Independent testing was performed on a separate cohort of 20 cases to compare network performances. The best-performing network was used for comparison against expert rater assessment in IA detection and segmentation. Quantitative evaluation of expert rater IA segmentation was also performed by comparing IA morphology quantified by parameters, such as size, aspect ratio, neck diameter, and undulation index, against DL predictions. Results: In the independent testing dataset, BN significantly outperformed DM in terms of Dice similarity coefficient DSC (0.875±0.0083 vs. 0.864±0.0075, p=0.004), while DM significantly outperformed BN in terms of precision (0.891±0.016 vs. 0.867±0.017, p&lt;0.001). Qualitative assessment confirmed the superiority of DM in segmenting the IAs located on cavernous ICA. Compared to DM, expert raters missed 7 IAs located on cavernous ICA. Furthermore, DM segmentation provided better measurement of neck diameter (p=0.009), aspect ratio (p=0.029) and shape parameters as compared to the expert rater assessment. Conclusions: A deep learning approach using DM can provide a high-fidelity solution for CTA segmentation of vessels and IAs in the cavernous ICA region.

Knowledge framework and emerging trends in intracranial aneurysm magnetic resonance angiography: a scientometric analysis from 2004 to 2020.

As magnetic resonance angiography (MRA) has been increasingly used in the follow-up of intracranial aneurysms (IAs) as a non-invasive technique, the knowledge framework and areas of research interest in intracranial aneurysms magnetic resonance angiography (IAMRA) change approximately every 10 years. However, few studies have quantitatively analyzed the published literature in this field. In the present study, we used scientometrics to survey the knowledge field, development trends, and research focus of IAMRA with the aim of providing a reference for further study. We collected articles on IAMRA published from 2004 (Jan 1, 2004) to 2020 (May 24, 2020). Web of Science Core Collection databases (WoSCCd) including the Science Citation Index Expanded were searched. An experienced staff member from the Department of Radiology at Southern Medical University, assisted in screening articles for relevant articles. We used ArcGIS (a mapping and location analytics platform) to perform geographic visualization. Excel 2016 was used to analyze the literature data, including number of publications, impact factor (IF), and publication year. CiteSpace V was used to conduct a series of literature feature clustering, including author co-citation analysis, reference co-citation analysis (RCA), and burst keywords analysis. A total of 1,272 articles on IAMRA published between 2004 and 2020 were included. Of 257 journals, American Journal of Neuroradiology (IF 2018: 3.256) published the most IAMRA articles (109 publications, 8.57%), followed by Journal of Neurosurgery (IF 2018: 4.131, 51 publications, 4.16%), and Neuroradiology (IF 2018: 2.504, 51 publications, 4.01%). Of 56 countries, the USA published the most, with 347 articles [27.28%, IF: 3.14 (average IF of all journals in the country)], followed by Japan (242 articles, 19.03%, IF: 2.38), Germany (135 articles, 10.61%, IF: 3.21), and China (101 articles, 7.94%, IF: 2.86). A total of 1387 institutions published articles, with the Mayo Clinic publishing the most (33 articles, 2.59%), followed by Shanghai Jiao Tong University (25 article, 1.97%), Seoul National University (23 articles, 1.81%), and University Medical Center Utrecht (19 articles, 1.49%). Of 399 authors, Rinkel ranked first with 19 articles, followed by Li MH (18 articles), Uchino A (15 articles), and Saito N (13 articles). Cluster RCA showed that the first cluster was "#0 growth", followed by "#1 Guglielmi detachable coils". Timeline views showed that the time span of "#0 growth" was the closest to today. The modularity value was 0.6971, and the mean silhouette value was 0.5477. According to the burst keyword analysis, "risk factors associated to rupture" was the topic with the strongest burst since 2017. Studies conducted in several countries suggested that age is inversely related to the risk of rupture, which implies the importance of MRA follow-up for patients of different age. From 2004 to 2020, the number of published IAMRA-related articles gradually increased. The USA and Western Europe lead in the field, with a concentration of cutting-edge talents and high-level scientific research institutions. A synthesis of the clustering results of RCA and burst keyword analysis indicated that unruptured IA growth, stent-assisted coil embolization, and risk factors associated to rupture were the current hotspots in IAMRA research.

Necessity of follow-up cerebral digital subtraction angiography after endovascular coiling or microsurgical cliping of ruptured intracranial aneurysms to exclude de novo or aneurysmal regrow and avoid its rupture: report of 2 cases

Objective – to improve treatment results of patients with ruptured brain aneurysms using follow-up cerebral digital subtraction angiography to avoid de novo or aneurismal regrow.Materials and methods. Analysis of follow-up cerebral digital subtraction angiography and treatment results of two patient (60 and 64-year-old females) with brain anterior communicated artery de novo aneurysm and regrowed aneurysm of an anterior communicated artery after microsurgical clipping.Results. Two patient underwent endovascular treatment of ruptured brain aneurysms after non follow-up cerebral digital subtraction angiography. In first case de novo aneurysm of anterior communicating artery and in second – regrowed aneurys of anterior communicating artery after surgical clipping. Both patients were discharged from the clinic in I and IV modified Rankin scale. Conclusions. Digital subtraction angiography follow-up of intracranial aneurysms treated by endovascular or microsurgical approach is important for the detection and prediction for the risk of bleeding (aneurysm recurrence and de novo aneurysm). There exist no guidelines on the frequency of monitoring and imaging modality to adopt and the monitoring is adapted on a case-by-case basis. Digital subtraction angiography is the gold standard for the evaluation of aneurysmal occlusion after coiling and microsurgical clipping and remains also necessary for evaluating other devices.

Safety and Efficacy of Low-Profile, Self-Expandable Stents for Treatment of Intracranial Aneurysms: Initial and Midterm Results - A Systematic Review and Meta-Analysis

Low-profile stents seem to be associated with a higher incidence of thromboembolic events compared with preexisting stents. We conducted a systematic review of 11 eligible reports and a meta-analysis of 7 reports with respect to the clinical efficacy and safety of low-profile stents. There were 217 intracranial aneurysms reported; 22% were ruptured aneurysms. In all, 72% were treated using single stenting, 19% were treated using overlapping stenting, and 6% were treated using balloon angioplasty followed by stenting; 3% were used to assess the flow diverter effect in a dissecting aneurysm or were treated using unexpected subtotal coil packing. On immediate postprocedural angiographic results, Raymond class I and II obliteration was obtained in 87% of the aneurysms. On angiographic results at 3-6 months, Raymond class I and II obliteration or stability was obtained in 79% of the aneurysms, and Raymond class III obliteration was obtained in 3% of the aneurysms. The recurrence rate on follow-up of intracranial aneurysms was 6.5% (5.7% with LEO Baby and 1.3% with LVIS Jr). The periprocedural complication rate was 12.4%. Periprocedural thromboembolism occurred in 6.5% of the cases. The rate of in-stent stenosis on follow-up of intracranial aneurysms was 10%. In the midterm result, the recurrence rate with use of low-profile, self-expandable stents was relatively low compared to that with use of other self-expandable stents. In the meta-analysis comparing LEO Baby with LVIS Jr, the obliteration rate at 6 months was not significantly different, but the periprocedural complication rate was relatively low with LVIS Jr.

Detection and characterization of intracranial aneurysms: a 10-year multidetector CT angiography experience in a large center

BackgroundCT angiography (CTA) is increasingly used for the detection, characterization, and follow-up of intracranial aneurysms. A lower threshold to request a CT angiogram may render a patient population that differs...

Time-resolved imaging of contrast kinetics does not improve performance of follow-up MRA of embolized intracranial aneurysms

SummaryBackgroundThe use of contrast media and the time-resolved imaging of contrast kinetics (TRICKS) technique have some theoretical advantages over time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. We prospectively compared the diagnostic performance of TRICKS and TOF-MRA with digital subtracted angiography (DSA) in the assessment of occlusion of embolized aneurysms.Material/MethodsSeventy-two consecutive patients with 72 aneurysms were examined 3 months after embolization. Test characteristics of TOF-MRA and TRICKS were calculated for the detection of residual flow. The results of quantification of flow were compared with weighted kappa. Intraobserver and interobserver reproducibility was determined.ResultsThe sensitivity of TOF-MRA was 85% (95% CI, 65–96%) and of TRICKS, 89% (95% CI, 70–97%). The specificity of both methods was 91% (95% CI, 79–98%). The accuracy of the flow quantification ranged from 0.76 (TOF-MRA) to 0.83 (TRICKS). There was no significant difference between the methods in the area under the ROC curve regarding both the detection and the quantification of flow. Intraobserver reproducibility was very good with both techniques (kappa, 0.86–0.89). The interobserver reproducibility was moderate for TOF-MRA and very good for TRICKS (kappa, 0.74–0.80).ConclusionsIn this study, TOF-MRA and TRICKS presented similar diagnostic performance; therefore, the use of time-resolved contrast-enhanced MRA is not justified in the follow-up of embolized aneurysms.

Wertigkeit der CT- und MR-Angiographie zur Diagnostik intrakranieller Aneurysmen

Digital subtraction angiography (DSA) is still considered the gold standard in neurovascular imaging. However, due to permanent progress in the field of cross-sectional imaging modalities many questions can be answered with these less invasive methods. The following article gives an overview of the principles of computed tomography angiography (CTA) and magnetic resonance angiography (MRA) and demonstrates the growing importance in the diagnosis and follow-up of intracranial aneurysms.

Long-term follow-up of Intracranial Aneurysms facilitated by three-dimensional reconstruction of DSA and MRA Imaging

Long-term follow-up of Intracranial Aneurysms facilitated by three-dimensional reconstruction of DSA and MRA Imaging

MR Angiography Follow-Up of Aneurysms Treated with Coils: Is There a Need for the Use of Gadolinium?

The authors of “MR Angiographic Follow-Up of Intracranial Aneurysms Treated with Detachable Coils: Evaluation of a Blood-Pool Contrast” report a series of 37 cerebral aneurysms treated with coils studied at 1.5T with time-of-flight (TOF) MR angiography (MRA) and contrast-enhanced (CE) MRA with a

MR angiographic follow-up of intracranial aneurysms treated with detachable coils: Is there a need for blood-pool agents?

MR angiographic follow-up of intracranial aneurysms treated with detachable coils: Is there a need for blood-pool agents?

Three-dimensional time-of-flight (3d tof) magnetic resonance angiography (mra) and contrast-enhanced mra of intracranial aneurysms treated with platinum coils

Contrast-enhanced magnetic resonance angiography (CE-MRA) is less prone to flow-related signal intensity loss than three-dimensional time-of-flight (3D TOF) MRA and may therefore be more sensitive for detection of residual patency in platinum coil-treated intracranial aneurysms. To compare MRA and CE-MRA in the follow-up of intracranial aneurysms treated with platinum coils. CE-MRA and 3D TOF MRA (pre- and postcontrast injection) of the intracranial vasculature was performed at 1.5T in 38 patients (47 aneurysms) referred for DSA in the follow-up of coiled intracranial aneurysms. DSA showed aneurysm patency in 22/47 investigations. Patent aneurysm components were observed with CE-MRA in 18/22 cases, and with 3D TOF MRA in 21/22 cases. There was no significant difference in patent aneurysm component size between CE-MRA and 3D TOF MRA. In addition, CE-MRA showed six, 3D TOF MRA before contrast injection showed seven, and 3D TOF MRA after contrast injection showed eight cases with patent aneurysm components not observed on DSA. 3D TOF MRA was highly sensitive for detection of patent aneurysm components, and at least as sensitive as CE-MRA. Residual aneurysm patency seems to be better visualized with MRA than with DSA in some cases.

Modern cross-sectional imaging in the diagnosis and follow-up of intracranial aneurysms

Digital subtraction angiography (DSA) is still considered the gold standard for most applications in neurovascular imaging. However, with the ongoing development of cross-sectional imaging modalities DSA is increasingly being replaced by less invasive methods. This contribution describes the diagnostic value and the increasing potential of computed tomography angiography (CTA) and magnetic resonance angiography (MRA) in the diagnosis and follow-up of intracranial aneurysms. The main role of CTA is in the diagnosis and therapy planning of ruptured aneurysms; in contrast, MRA plays an increasingly important role in the screening for asymptomatic aneurysms (especially in cases of familial subarachnoid hemorrhage) and in the follow-up after endovascular therapy with coils and/or intracranial stents. Technical issues concerning examination technique are covered here as well as an approach to advanced postprocessing of the image data. Furthermore, a brief outlook on the impact of new developments (MRA with parallel imaging and at 3.0 T) is given.

Contrast-enhanced transcranial Doppler sonography in the follow-up of intracranial aneurysms after endovascular treatment

Two pilot studies on a small number of patients demonstrated the feasibility of transcranial Doppler ultrasound evaluation in the follow-up of intracranial aneurysms treated with detachable coils. This prospective study aimed to assess the sensitivity of contrast-enhanced transcranial echo-Doppler in detecting partial aneurysmal occlusion following endovascular treatment. Transcranial Doppler sonography (TCD) with contrast administration and magnetic resonance angiography (MRA) or angiography were carried out after endovascular treatment in 92 patients for 98 aneurysms of the anterior circulation. In 18% of cases, the quality of ultrasound exploration was deemed unsatisfactory for evaluation of the aneurysmal site. Results were concordant in 63% of patients (49/78). When occlusion appeared satisfactory at angiography or MRA, the result was concordant with TCD in 68% of cases (44/77). When a residual aneurysm was detected, TCD sensitivity was 38% (8/18). An analysis of subgroups failed to disclose anatomic or morphological aneurysm features in which transcranial echo-Doppler is sufficiently sensitive and specific to detect possible residual aneurysm or recanalisation. In our experience, even after contrast administration TCD is not sufficiently sensitive or specific in the detection of residual aneurysm to replace angiography or MRA.

Follow-up of intracranial aneurysms in autosomal-dominant polycystic kidney disease

Approximately 8% of autosomal-dominant polycystic kidney disease (ADPKD) patients have intracranial aneurysms. The risk of growth and rupture of those discovered by presymptomatic screening is key to the feasibility and success of a screening program. This study was initiated to ascertain this risk. ADPKD patients were offered screening with magnetic resonance (MR) imaging that included three-dimensional time-of-flight MR angiographic and three-dimensional phase-contrast sequences. Patients with aneurysms were recommended periodic surveillance, initially at 6 months and yearly, and less frequently after demonstration of their stability. Twenty-two saccular and one fusiform aneurysms were detected at the initial screening in 21 patients from 19 families (seven men and 14 women, 47.9 +/- 10.6 years old). All the saccular aneurysms were small (mean diameter 3.5 mm, range 2.0 to 6.5 mm) and the majority (77%) in the anterior circulation. Two patients died from unrelated causes without further follow-up. One patient was lost to follow-up. A new 2 mm middle cerebral artery aneurysm developed in one patient. One aneurysm increased from a size of 4 mm to 5 mm after a follow-up of 105 months. No aneurysmal development or growth occurred in the remaining 16 patients. No aneurysmal rupture occurred during a mean imaging follow-up of 81 months and a mean clinical follow-up of 92 months. During the period of the study, two additional ADPKD patients, with three intracranial aneurysms detected elsewhere by presymptomatic MR angiographic screening, were referred for surgical treatment. The larger size of these aneurysms (10, 8, and 8 mm) probably reflects referral bias. Most intracranial aneurysms detected by presymptomatic screening in ADPKD patients are small and in the anterior circulation. The follow-up results do not suggest an increased risk for growth and rupture, compared to those of intracranial aneurysms in the general population. These data do not support widespread screening for intracranial aneurysms in the ADPKD population.

The Reliability of MR Angiography as the Sole Imaging Method for Non-Invasive Follow-up of Intracranial Aneurysms Treated with Guglielmi Detachable Coils

The Reliability of MR Angiography as the Sole Imaging Method for Non-Invasive Follow-up of Intracranial Aneurysms Treated with Guglielmi Detachable Coils

Follow-up of intracranial aneurysms in autosomal dominant polycystic kidney disease by magnetic resonance angiography.

The purpose of this study was to assess the value of magnetic resonance angiography (MRA) in the follow-up of patients with autosomal dominant polycystic kidney disease (ADPKD) and saccular intracranial aneurysms (ICA), the risk of MRA-defined growth of asymptomatic incidental ICA, and the rate of development of MRA-defined de novo ICA in these patients. Between 1989 and 1995, 15 asymptomatic incidental ICA measuring 1.5 to 6.5 mm in diameter, three symptomatic aneurysms, and one asymptomatic concurrent aneurysm were detected by MRA in this study in 18 patients from 15 families. Four-vessel cerebral angiography in the three patients with symptomatic ICA and autopsy in one patient with an asymptomatic incidental ICA did not reveal additional aneurysms undetected by MRA. Thirty MRA studies were obtained in 10 of the 15 patients with incidental ICA during a cumulative clinical follow-up of 500 months (mean, 33.3; range, 0 to 65 months). The cumulative interval between the initial and the last MRA was 306 months (mean, 30.6; range, 14 to 51 months). No change in aneurysmal size or development of de novo aneurysms was detected. Eight MRA studies were obtained in the three patients with symptomatic ICA during a cumulative clinical follow-up of 130 months (mean, 43.3; range, 23 to 64 months). The cumulative interval between the first and the last MRA was 95 months (mean, 31.7; range, 15 to 49 months). Development of de novo aneurysms was not detected. These results indicate that MRA is an appropriate technique to follow small asymptomatic incidental ICA in patients with ADPKD and that the risk for rapid growth of these aneurysms is low. Although the results of this study should be viewed as preliminary, they do not suggest a higher rate of development of de novo aneurysms or a higher frequency of multiple aneurysms in patients with ADPKD and ICA as compared with patients with sporadic ICA in the general population.