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Meta-analysis of computed tomography angiography versus magnetic resonance angiography for intracranial aneurysm


Abstract and Figures

Background: Whether the diagnosis value of computed tomography angiography (CTA) for intracranial aneurysm is in accordance with magnetic resonance angiography (MRA) remains inconclusive. This meta-analysis aims to synthesize relevant studies to compare the diagnostic efficacies of the 2 methods. Methods: Potentially relevant studies were selected through PubMed, Embase, Wanfang, Chongqing VIP, and China National Knowledge Infrastructure databases by using the core terms "computer tomography angiography" (CTA) and "magnetic resonance angiography" (MRA) and "intracranial aneurysm*" in the titles, abstracts, and keywords of the articles. Quality Assessment for Diagnostic Accuracy Studies (QUADAS-2) was utilized to evaluate the quality. Pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were count. Summary receiver operating characteristic curves (SROC) and area under the curve (AUC) were used to summarize the overall diagnostic performance. Statistical analyses were performed by Stata version 12.0 and MetaDisc 1.4 software. Results: Ten articles were identified in this current paper. For CTA, the pooled estimates of diagnostic parameters for intracranial aneurysm were as follows: sensitivity, 0.84 (95%CI = 0.81-0.86); specificity, 0.85 (95%CI = 0.79-0.89); PLR, 4.09 (95%CI = 2.45-6.81); NLR, 0.18 (95%CI = 0.11-0.28); DOR, 23.74 (95%CI = 10.49-53.74); AUC, 0.90, respectively. For MRA, the pooled estimates of diagnostic parameters for intracranial aneurysm were as follows: sensitivity, 0.80 (95%CI = 0.77-0.83); specificity, 0.87 (95%CI = 0.82-0.91); PLR, 3.61 (95%CI = 1.72-7.55); NLR; 0.27 (95%CI = 0.21-0.35); DOR, 16.77 (95%CI = 7.38-38.11); AUC, 0.87, respectively. No significant difference was found the AUC value between CTA and MRA for intracranial aneurysm (Z = 0.828, P > .05). Conclusion: This comprehensive meta-analysis demonstrated that the diagnosis value of CTA was in accordance with MRA for intracranial aneurysm. However, considering the limitation of sample size, the results should be treated with caution.
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Meta-analysis of computed tomography
angiography versus magnetic resonance
angiography for intracranial aneurysm
Xiaodan Chen, MD
, Yun Liu, MD
, Huazhang Tong, MD
, Yonghai Dong, MD
, Dongyang Ma, MD
Lei Xu, MD
, Cheng Yang, MD
Background: Whether the diagnosis value of computed tomography angiography (CTA) for intracranial aneurysm is in accordance
with magnetic resonance angiography (MRA) remains inconclusive. This meta-analysis aims to synthesize relevant studies to
compare the diagnostic efcacies of the 2 methods.
Methods: Potentially relevant studies were selected through PubMed, Embase, Wanfang, Chongqing VIP, and China National
Knowledge Infrastructure databases by using the core terms computer tomography angiography(CTA) and magnetic resonance
angiography(MRA) and intracranial aneurysmin the titles, abstracts, and keywords of the articles. Quality Assessment for
Diagnostic Accuracy Studies (QUADAS-2) was utilized to evaluate the quality. Pooled sensitivity, specicity, positive likelihood ratio
(PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were count. Summary receiver operating characteristic curves
(SROC) and area under the curve (AUC) were used to summarize the overall diagnostic performance. Statistical analyses were
performed by Stata version 12.0 and MetaDisc 1.4 software.
Results: Ten articles were identied in this current paper. For CTA, the pooled estimates of diagnostic parameters for intracranial
aneurysm were as follows: sensitivity, 0.84 (95%CI =0.810.86); specicity, 0.85 (95%CI =0.790.89); PLR, 4.09 (95%CI =2.45
6.81); NLR, 0.18 (95%CI =0.110.28); DOR, 23.74 (95%CI =10.4953.74); AUC, 0.90, respectively. For MRA, the pooled estimates
of diagnostic parameters for intracranial aneurysm were as follows: sensitivity, 0.80 (95%CI =0.770.83); specicity, 0.87 (95%CI =
0.820.91); PLR, 3.61 (95%CI =1.727.55); NLR; 0.27 (95%CI =0.210.35); DOR, 16.77 (95%CI =7.3838.11); AUC, 0.87,
respectively. No signicant difference was found the AUC value between CTA and MRA for intracranial aneurysm (Z=0.828, P>.05).
Conclusion: This comprehensive meta-analysis demonstrated that the diagnosis value of CTA was in accordance with MRA for
intracranial aneurysm. However, considering the limitation of sample size, the results should be treated with caution.
Abbreviations: AUC =area under the curve, CTA =computed tomography angiography, DSA =digital subtraction angiography,
DOR =diagnostic odds ratio, FN =false negative, FP =false positive, MRA =magnetic resonance angiography, NLR =negative
likelihood ratio, PLR =positive likelihood ratio, QUADAS =Quality Assessment for Diagnostic Accuracy Studies, SROC =summary
receiver operating characteristic curves, TN =true negative, TP =true positive.
Keywords: CTA, intracranial aneurysm, meta-analysis, MRA
1. Introduction
The prevalence of intracranial aneurysm in the general popula-
tion is approximately 1% to 5%.
Ruptured intracranial
aneurysm is reportedly the dominant cause leading to non-
traumatic subarachnoid hemorrhage, and it can give raise to
severe disability and even death.
Thus, a precise diagnosis is
especially important to the patients with intracranial aneurysm.
In clinical practice, the conventionally accepted gold standard
for the detection of intracranial aneurysm is digital subtraction
angiography (DSA).
Despite the high sensitivity and specici-
ty of DSA, several aws have restricted its wide application. First
and foremost, the high cost of DSA puts the technology beyond
some families. Secondly, DSA requires a high level of skill. Thirdly,
DSA can lead to a minimal invasive procedure, such as cerebral
thromboembolism and contrast nephrotoxicity.
Thus, an
imaging tool that is fast, efcient, convenient, affordable, and
noninvasive is required in clinical practice.
Computed tomography angiography (CTA) and magnetic
resonance angiography (MRA) have been widely used to screen
Editor: Kou Yi.
XC, YL, HT, and YD contributed equally to this manuscript.
Formatting of funding sources: This research did not receive any specic grant
from funding agencies in the public, commercial, or not-for-prot sectors.
The authors have no conicts of interest to disclose.
Department of Science and Education, Jiangxi Provincial Cancer Hospital,
Wards of Neurology Medicine,
Department of Cancer Radiotherapy, Jiangxi
Provincial Peoples Hospital,
Jiangxi Provincial Center for Disease Control and
Prevention, Nanchang,
Nanhui Mental Health Center, Pudong New Area,
Shanghai, China.
Correspondence: Yonghai Dong, Jiangxi Provincial Center for Disease Control
and Prevention, Nanchang, 330029, China (e-mail:
Copyright ©2018 the Author(s). Published by Wolters Kluwer Health, Inc.
This is an open access article distributed under the Creative Commons
Attribution-NoDerivatives License 4.0, which allows for redistribution, commercial
and non-commercial, as long as it is passed along unchanged and in whole, with
credit to the author.
Medicine (2018) 97:20(e10771)
Received: 4 January 2018 / Accepted: 23 April 2018
Systematic Review and Meta-Analysis Medicine®
intracranial aneurysms. Prior clinical evaluations that compared
CTA or MRA with DSA revealed that the diagnostic value of
CTA or MRA approaches that of DSA. A recent investigation
pooled 8 studies to explore the accuracy of subtraction CTA
compared with DSA for diagnosing intracranial aneurysm; the
pooled sensitivity and specicity were 96% and 91%, respec-
tively. In addition, the author also suggested that CTA is a highly
sensitive, specic and noninvasive imaging method to diagnose
intracranial aneurysms. Another investigation
pooled 26
studies that addressed the diagnostic value of MRA based on
DSA; for time of ight-MRA, the sensitivity and specicity were
86% and 84%, respectively, with rates of 86% and 89%,
respectively, for contrast-enhanced MRA. Our review of previous
articles indicates that comparative weakness of studies compar-
ing the diagnostic value between CTA and MRA performed on
the same objects with intracranial aneurysms, with varied results.
For example, Xu et al
studied 98 patients with suspected
aneurysms to compare the diagnosis accuracy of CTA and MRA;
the sensitivity and specicity was 95% and 67% for CTA, and
71% and 50% for MRA. However, Hiratsuka et al
found the
diagnosis value of the 2 methods was similar.
This meta-analysis systematically compares the diagnosis value
between CTA and MRA for intracranial aneurysms.
2. Materials and methods
2.1. Literature search
This meta-analysis was designed according to the Preferred
Reporting Items for Systematic Reviews and Meta-Analysis
(PRISMA) recommendations. Two investigators independently
conducted a comprehensive literature search using several large
databases using the terms computer tomography angiography
(CTA) and magnetic resonance angiography(MRA) and
intracranial aneurysmin the article titles, abstracts, and
keywords. The databases included PubMed-Medline (1966
October 2017), Embase (1950October 2017), China National
Knowledge Infrastructure (CNKI, 1994October 2017), Wan-
fang Data (1980October 2017), and Chongqing VIP (1989
October 2017). Also, the reference lists of the identied articles
were evaluated to identify relevant studies.
2.2. Study selection
Two reviewers (YY and LM) independently reviewed the
potential articles on the basis of predetermined inclusion
and exclusion criteria. At the end of the review, in case of
divergences of opinion for the articles, a third reviewer
evaluated whether the article in question was eligible. All the
selected studies needed to meet the following inclusion criteria:
studies adopted a clinical study design based on a human
population; intracranial aneurysms were identied by CTA or
MRA; studies provided sufcient information to calculate effect
size; articles were in English or Chinese; and in case of duplicated
cohorts, the study with the largest number of patients were
included. Any study that failed to meet these criteria was
2.3. Data extraction
The same 2 investigators independently extracted the study
information using a standardized form for each study. The
basic information included the name of the rst author, year of
publication, country, mean age of participants, and sample size.
In addition, they extracted the information with true positive
(TP), false positive (FP), false negative (FN), and true negative
(TN) from each study to pool the effect size of diagnosis
accuracy. If required, information that had previously been
omitted was retrieved by communication with the authors of
the studies.
2.4. Quality assessment
In this review, Chen X and Xiong M independently assessed the
quality of the included studies according to the Quality
Assessment of Diagnostic Accuracy Studiesversion 2 (QUA-
DAS-2) scale.
This scale has 14 items and covers 4 domains
(patient selection, index test, reference standard, ow, and
timing). For each case, the answer should be provided as yes/no/
unclear in order to evaluate it. Yesindicated a low risk of bias
for this domain. Noor unclearpresented lacking the details
or not certain, and indicated a potential bias.
2.5. Ethical approval
No ethical approval was required because all the data were
extracted from the previous published articles.
2.6. Statistical analyses
Statistical analyses were carried out by Stata version 12.0 (Stata
Corporation, College Station, TX) and MetaDisc 1.4 (XI.
Cochrane Colloquium, Barcelona, Spain). In this review, we
pooled sensitivity, specicity, positive likelihood ratio (PLR),
negative likelihood ratio (NLR), and diagnostic odds ratio
(DOR) with 95% condence intervals (CI) to evaluate CTA and
MRA diagnosis accuracy for intracranial aneurysms. In addition,
summary receiver-operating curves (SROC) and area under the
SROC curve (AUC) were performed to explain the interaction
between sensitivity and specicity and the diagnostic ability
respectively. Q-statistics was used to evaluate the heterogeneity.
was determined to assess the degree of heterogeneity between
studies. If P>.10 by Qtest and I
<50%, no obvious
heterogeneity existed.
If so, a xed effects model (Mantel
Haenszel method) was adopted. Conversely, a random effects
model (DerSimonian and Laird method) was performed.
further determine the difference in AUC between CTA and MRA
for intracranial aneurysm, Ztest was performed.
In diagnostic accuracy studies, the predominant cause of
heterogeneity was threshold effect. In order to identify the
threshold effect, Spearmans correlation coefcient between logit
of sensitivity and logit of (1-speciticity) was calculated. P<.05
indicated that the threshold effect existed.
2.7. Publication bias
Publication bias was accessed by Deeksfunnel plot asymmetry
test. If P<.05, the potential publication bias was absent.
3. Results
3.1. Literature search
In this meta-analysis, the initial search strategy yielded 376
relevant citations. Of these, 74 articles were retrieved for detailed
evaluation and 62 were excluded. Finally, 10 articles met the rigid
inclusion criteria.
The owchart of study selection is
shown in Figure 1.
Chen et al. Medicine (2018) 97:20 Medicine
3.2. Study characteristics
The main characteristics of the included studies are shown in
Table 1. The publication year ranged from 2001 to 2017. Among
the 10 studies, 868 subjects were evaluated by CTA and 872 were
by MRA. Six studies were conducted in China,
3 in the
United Kingdom,
, and one in the United States.
studies had a prospective design,
, 6 had a retrospective
and 1 did not report detailed information.
the 10 studies, 2 used DSA and operation as the reference
standard for the nal result of intracranial aneurysms
and 6
used DSA as the reference standard.
Details were
not provided for the remaining 2 studies.
3.3. Quality assessment
We used the QUADAS-2 checklist to assess the quality of the
included studies. The details were provided in Table 2. The
overall quality of the included studies was favorable, with all
studies fullling 11 or more of the 14 items.
3.4. Diagnostic accuracy
3.4.1. CTA. To assess the threshold effect heterogeneity, the
Spearman correlation coefcient was used to analyze the
diagnostic threshold. The Spearman correlation coefcient for
CTA was 0.299 (P=.402), which suggested that not enough
evidence supported a threshold effect heterogeneity. The pooled
results showed that the combined sensitivity, specicity, PLR, and
NLR were 0.84 (95% CI, 0.810.86; Fig. 2A), 0.85 (95% CI,
0.790.89; Fig. 2B), 4.09 (95% CI, 2.456.81; Fig. 2C), and 0.18
(95% CI, 0.110.28; Fig. 2D), respectively. The pooled DOR was
Figure 1. Flowchart of study selection procedure.
Table 1
Characteristics of included studies.
Author Year Country Age Design Gold standard Total TP FP FN TN TP FP FN TN
1 Tang 2013 China CTA: 3176;MRA: 2977 Retrospective DSA and operation 36 17 0 1 1 12 2 2 1
2 White 2001 UK 41(1971) Prospective NA 114 36 6 9 63 32 2 13 67
3 Chen 2016 China 3168 Retrospective DSA 120 90 3 14 8 82 7 22 8
4 Hiratsuka 2008 USA 60.2 ±10.8 (3278) Prospective DSA 46 36 0 2 8 37 1 2 7
5 Cui 2016 China NA Retrospective DSA and operation 48 19 1 0 1 16 3 2 1
6 White 2003 UK 45(2170) NA NA 60 24 4 6 26 21 3 9 27
7 White 2001 UK 1975 Prospective DSA 142 52 10 11 69 47 5 16 74
8 Li 2009 China 3878 Retrospective DSA 58 54 0 3 1 52 0 5 1
9 Xu 2017 China 52.4 ±1.2(2576) Retrospective DSA 98 87 1 5 2 66 1 27 1
10 Zhao 2015 China NA Retrospective DSA 198 119 10 53 16 145 6 27 20
CTA =computed tomography angiography, DSA =digital subtraction angiography, FN =false-negative, FP =false-positive, MRA =magnetic resonance angiography, NA =not available, TN =true negative, TP =
true positive.
Table 2
Quality assessment of included studies.
ID Study 1 2 3 4 5 6 7891011121314
1 Tang et al
2 White et al
3 Chen et al
4 Hiratsuka et al
5 Cui et al
6 White et al
7 White et al
10 Zhao et al
Chen et al. Medicine (2018) 97:20
Figure 2. The pooled diagnostic indices for the diagnosis of intracranial aneurysm through CTA (A) sensitivity (B) specicity (C) positive LR (D) Negative LR. CTA =
computed tomography angiography, LR =likelihood ratio.
Figure 3. Diagnostic odds ratio (DOR) (A) CTA (B) MRA. CTA =computed tomography angiography, DOR =diagnostic odds ratio, MRA =magnetic resonance
Figure 4. Summary receiver characteristics (SROC) (A) CTA (B) MRA. CTA=computed tomography angiography, MRA =magnetic resonance angiography,
SROC =summary receiver operating characteristic curves.
Chen et al. Medicine (2018) 97:20 Medicine
23.74 (95% CI, 10.4953.74; Fig. 3A). The SROC curve revealed
a Q value of 0.83, and the AUC was 0.90 (Fig. 4A). The result of
Deeksfunnel plot asymmetry test suggested no evidence for the
presence of publication bias (P=.56; Fig. 5A).
3.4.2. MRA. The Spearman correlation coefcient for the
diagnostic threshold of MRA was 0.358 (P=.310). This
indicated insufcient evidence of heterogeneity resulting from
threshold effect. The overall pooled sensitivity, specicity, PLR,
and NLR were 0.80 (95% CI, 0.770.83; Fig. 6A), 0.87 (95% CI,
0.820.91; Fig. 6B), 3.61 (95% CI, 1.727.55; Fig. 6C), and 0.27
(95% CI, 0.210.35; Fig. 6D), respectively. The pooled DOR was
16.77 (95% CI, 7.3838.11; Fig. 3B). The SROC curve showed
the Q value was 0.80, and the AUC was 0.87 (Fig. 4B). The result
of Deeksfunnel plot asymmetry test indicated there was no
publication bias (P=.15; Fig. 5B).
3.4.3. AUC value between CTA and MRA. In this study, the
AUC index was used to compare the difference of diagnosis value
between CTA and MRA for intracranial aneurysm. We found
there was no signicant difference between the 2 methods (Z=
0.828, P>.05).
4. Discussion
For the detection of intracranial aneurysm, CTA, MRA, and DSA
are frequently used medical imaging methods. DSA is widely
acknowledged as the gold standard. CTA has essentially replaced
Figure 5. Deeksfunnel plot (A) CTA (B) MRA. CTA =computed tomography angiography, MRA =magnetic resonance angiography.
Figure 6. The pooled diagnostic indices for the diagnosis of intracranial aneurysm through MRA (A) sensitivity (B) specicity (C) positive LR (D) negative LR. LR =
likelihood ratio, MRA =magnetic resonance angiography.
Chen et al. Medicine (2018) 97:20
DSA to detect intracranial aneurysms in many medical
institutions because of the lower cost. Furthermore, MRA is
widely used to detect the vascular disease because of its high
denition and noninvasive nature.
Although some studies have demonstrated the high sensitivity
and specicity of CTA and MRA for intracranial aneurysms, no
systematic review has evaluated which is better. This meta-
analysis is the rst comparative evaluation of the diagnostic
performance of CTA and MRA for the detection of intracranial
aneurysms. Ten studies met the inclusion criteria. The studies
collectively comprised 868 patients evaluated by CTA and 872
patients evaluated by MRA. The inclusion of studies from China,
UK, and USA resulted in inevitable language bias. According to
the QUADAS-2 checklist, the qualities of the included studies
were favorable. Overall, based on several indexes in this meta-
analysis, such as sensitivity, specicity, PLR, NLR, DOR, and
AUC, CTA and MRA both had a high diagnostic value for
intracranial aneurysm.
For diagnosing intracranial aneurysm, CTA had a higher
sensitivity (0.84, 95% CI, 0.810.86 vs 0.80, 95% CI, 0.770.83)
and a slight lower specicity (0.85, 95% CI, 0.790.89 vs 0.87,
95% CI, 0.820.91) than MRA, which suggested that CTA is
better able to recognize the true patients with intracranial
aneurysm, despite the slightly higher false negative rate. In this
study, the AUC of CTA and MRA for diagnosing intracranial
aneurysm was 0.90 and 0.87, respectively. This indicates that
CTA has a slight higher accuracy than MRA in diagnosis of
intracranial aneurysms on the surface, which is consistent with
several prior studies.
A recent systematic review
involving 5 retrospective studies and thirteen prospective studies
evaluated the diagnostic value of three-dimensional time-of-ight
MRA to detect intracranial aneurysm; the sensitivity, specicity,
and AUC (0.89, 0.94, and 0.96, respectively) indicated that the
technique was an excellent diagnostic method. However,
compared the AUC value of CTA with MRA for intracranial
aneurysm through Ztest, we did not nd a statistic difference
between the 2 methods (Z=0.828, P>.05).
The use of CTA or MRA to diagnose intracranial aneurysm
has advantages and disadvantages. For instance, El Khalidi
carried out 130 patients with nontraumatic acute subarachnoid
haemorrhage to assess the usefulness of multislice CTA in
identifying cerebral aneurysms compared with intra-arterial
DSA; the sensitivity of CTA was similar to DSA, even for
intracranial aneurysms <3 mm in size. For intracranial aneur-
ysms 5 mm in size, contrast-enhanced MRA reportedly has a
lower diagnostic value than CTA, with CTA recommended as the
preferred method for the 5 mm intracranial aneurysms.
of the turbulent ow within aneurysms revealed
different visualizations of the aneurysms with CTA and MRA
and the ndings indicated that the sensitivity of the 2 methods in
diagnosing intracranial aneurysms relies mainly on sub-mm slice
thickness for MRA and narrow collimation for CTA, respective-
ly. However, in the present meta-analysis, we could not
distinguish the relative performance advantage of CTA and
MRA for different size of tumors because of insufcient
information in the included studies.
Several limitations should be considered. First and foremost,
despite the comprehensive search strategy, with screening of
the literature, study selection, extraction of data, and
independent assessment of study quality, only 10 articles were
included. The limited number of studies might inuence the
results. Further high-quality studies on a larger scale are
needed. Secondly, the exclusion of other than English studies
might have led to an inevitable publication bias. Thirdly,
because of the limitation of extracted data, we were not able to
analyze the value of CTA or MRA for detecting different
periods of intracranial aneurysm.
In conclusion, this comprehensive meta-analysis results that
CTA and MRA both have the same and high diagnostic value for
intracranial aneurysm. However, considering the limitation of
sample size, the results should be viewed with caution.
XC, YD, and YL designed the study and wrote the manuscript.
DM and LX performed the statistical analysis. HT, YL and CY
discussed the results.
Author contributions
Conceptualization: Yonghai Dong.
Data curation: Dongyang Ma.
Formal analysis: Dongyang Ma, Lei Xu.
Investigation: Xiaodan Chen.
Methodology: Yonghai Dong.
Project administration: Yonghai Dong.
Supervision: Cheng Yang.
Writing original draft: Yun Liu, Yonghai Dong.
Writing review & editing: Xiaodan Chen, Huazhang Tong.
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... According to the experimental results, MRI and CT + MRI diagnosis for CA showed higher positive rates in contrast to the CT diagnosis, with statistical differences (P < 0.05); MRI diagnosis showed obviously higher DCR than CT but visibly lower DCR than CT + MRI (P < 0.05). is indicated that MRI diagnosis based on the LRMD algorithm had a higher detection rate of CA and had a higher clinical promotion value. Such results were consistent with the research conclusions of Chen et al. [18], which suggested that the algorithm had a good denoising effect. e accuracy, sensitivity, and specificity of CT diagnosis were 92.71%, 84.94%, and 80.71%, respectively, while those of MRI diagnosis under the LRMD algorithm were 96.28%, 88.76%, and 90.62%, respectively. ...
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This study was to analyze the diagnostic effects of computed tomography (CT) and magnetic resonance imaging (MRI) in patients with cerebrovascular diseases (CVDs) based on low-rank matrix denoising (LRMD) algorithm. The LRMD algorithm was adopted for MRI diagnosis and CT diagnosis for comparative analysis. 129 CVD patients were selected as the research objects, 43 cases were diagnosed by CT, 43 cases were diagnosed by MRI under LRMD, and the other 43 cases were diagnosed by CT + MRI. The results showed that the diagnostic compliance rates (DCRs) of CT group in the cerebral hemorrhage (CH), cerebral infarction (CI), and cerebral aneurysm (CA) were 95.1%, 94.7%, and 70%, respectively, while those in the MRI group were 99.01%, 97.71%, and 100%, respectively. Thus, it was obtained that MRI diagnosis was much better than CT diagnosis, and CT + MRI showed the best diagnosis efficacy, showing statistical differences (P
... [25] From meta-analysis study, estimated sensitivity and specificity of CTA are 84% and 85%, respectively. [5] us, we adjusted the prevalence using Greenland's method to decrease biases. [7] e estimated prevalence of familial UIA among ai populations was 9.05% which appeared to be higher than that in other Asian countries. ...
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Background The prevalence of familial unruptured intracranial aneurysm (UIA) in Thai population was unknown. Methods Our study population comprised first-degree relatives of patients who were diagnosed with aneurysmal subarachnoid hemorrhage (aSAH) in two cerebrovascular neurosurgical centers from January 2018 to December 2018. The volunteers underwent three-dimensional time-of-flight magnetic resonance angiography for screening intracranial aneurysms (IA). Those who were reported positive or suspected of IA then underwent computed tomography angiography for confirmation. Results We identified 12 patients who had 12 unruptured IAs (UIAs) from among 93 first-degree relatives. The prevalence of UIA among our study population was 12.9%. An estimated prevalence of UIA among Thai population was 9.05% (95% confidence interval [CI] 7.32–10.78). Of the 93 relatives, 84 had only one first-degree relative who suffered aSAH. Siblings posed a higher risk for UIA than offspring (16% vs. 9.5%), but the difference was not statistically significant (odds ratio 1.810, 95% CI 0.50–6.50, P = 0.274). The most common aneurysm location was the anterior cerebral artery territory (50%). Conclusion The prevalence of familial UIA in a Thai population was relatively high. There was no significant between-group difference in the occurrence of UIA between the siblings and offspring of the aSAH patients.
... According to the authors the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and AUC of CTA were as high as 71%, 94%, 9.39, 0.32, 28.32, and 0.856, respectively [29,30]. Finally, in a comprehensive meta-analysis study by Chen et al., it was demonstrated that the diagnostic value of CTA for IAs was in accordance with that of MRA [31]. It needs to be emphasised that the reported CTA diagnostic accuracy in all the above primary and meta-analytic studies has been calculated with the consideration of the presence of the IAs as a dichotomous variable (present or absent, aneurysm >3 mm or aneurysm <3 mm). ...
Zusammenfassung Klinisches Problem Rauchen beeinflusst das kardiovaskuläre System des Körpers. Primär führt es entweder zu atheromatösen Plaques mit potenzieller Gefäßstenosierung oder zu aneurysmatischen Gefäßveränderungen mit potenzieller Rupturgefahr. Radiologische Standardverfahren Je nach Lokalisation ermöglicht die Sonographie eine initiale Einschätzung der Veränderungen. Eine Angiographie in Kombination mit Computertomographie (CT) oder Magnetresonanztomographie (MRT) ermöglicht die weiterführende Beurteilung und ggf. Therapieplanung. Ohne klinische Symptomatik wird bei Rauchern ohne sonstige Risikofaktoren oder Komorbiditäten keine bildgebende Diagnostik lediglich aufgrund des Rauchens empfohlen. Methodische Innovationen Aktuelle Leitlinien der entsprechenden Pathologien erkennen das Rauchen einstimmig als modifizierbaren Risikofaktor für kardiovaskuläre Erkrankungen an, weshalb stets eine Raucherentwöhnung als erster Schritt zur Prävention sekundärer Akutereignisse empfohlen wird. Bei Verdacht auf ein chronisches Koronarsyndrom erhöht das Rauchen die klinische Wahrscheinlichkeit, wodurch eher eine bildgebende Diagnostik indiziert werden sollte. Leistungsfähigkeit Obwohl das Rauchen weitreichende Folgen am gesamten kardiovaskulären System zeigt, bleibt zu klären, ob Raucher durch eine Modifikation aktueller Leitlinien zur Vorsorge und Diagnose hinsichtlich harter klinischer Endpunkte profitieren würden. Empfehlung für die Praxis Raucher sollten aufgrund des deutlich erhöhten kardiovaskulären Risikos zu einer Raucherentwöhnung beraten werden. Hinsichtlich konkreter Krankheitsbilder bedingt das Rauchen keine prinzipielle Modifikation der bildgebenden Abklärung, bei intermediärem Risiko kann aber tendenziell früher zur Bildgebung geraten werden.
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Cochlear implantation is a standard treatment option due to expanding indications. Cranial magnetic resonance imaging (cMRI) has become a widespread diagnostic tool. Therefore, an increased number of cochlear implant (CI) users are undergoing cMRI scans. This study aimed to investigate the issue of the CI magnet impacting MRI quality and artifacts. 1.5 T and 3 T MRI scans with 4 defined sequences (T2-TSE, T2-TIRM, T1-3D-MPRAGE, and TDI) were performed on a phantom with a CI (SYNCHRONY System by MED-EL Austria) in place. The resulting MRI artifacts were retrospectively compared to MRI artifacts observed in patients with a CI. All images were transferred to AMIRA and visualized by manual segmentation. Usable image quality was achieved in three sequences (T2-TSE, T2-TIRM and T1-mprage). Observed artifacts differed in shape and size depending on the sequence. Maximum diameters of signal void areas ranged from 58 × 108 × 98 mm to 127 × 123 × 153 mm. Image distortions were larger. MRI artifacts caused by the SYNCHRONY system are asymmetric with varying shape, depending on the sequence. The phantom artefacts are similar to those in CI users. Considering the observed asymmetry, the hypothesis of varying implantation locations resulting in varying positions of the signal void area needs to be further investigated.
La recanalisation post-coiling des anévrismes intracrâniens est une problématique récurrente dans le domaine de la neuroradiologie interventionnelle qui limite l’efficacité du traitement à long terme. En effet, lors du traitement endovasculaire par coiling d’un anévrisme intracrânien il ne s’agit pas seulement de combler une poche avec du métal. Au-delà de la complexité technique du geste en soi, les phénomènes biologiques induits par le traitement sont à prendre en considération pour obtenir une cicatrisation optimale. Le thrombus induit par les coils implantés dans l’anévrisme est également un substrat essentiel à la cicatrisation des anévrismes après traitement, car il est un support à la recolonisation de l’anévrisme par des cellules mésenchymateuses.Nous avons étudié dans cette thèse les phénomènes biologiques et les mécanismes histopathologiques de la cicatrisation anévrismale impliqués dans le traitement endovasculaire des anévrismes intracrâniens par coiling. A partir du constat d’un défaut de cicatrisation avec les dispositifs actuels, nous proposons une approche innovante visant à optimiser la cicatrisation des anévrismes par les coils recouverts de fucoïdane. Ce polysaccharide sulfaté est capable d'une part d’interagir avec les facteurs de croissance nécessaires à la cicatrisation et, d'autre part, de favoriser la formation d'un thrombus en se liant à la P-sélectine surexprimée par les plaquettes activées. Les travaux expérimentaux présentés dans cette thèse sont issus d’une collaboration pluridisciplinaire associant chimistes, biologistes et neuroradiologues interventionnels.Un financement a été obtenu de la Fondation pour la Recherche Médicale en octobre 2018 dans le cadre de l’appel à projet “Pionniers de la Recherche – Chimie pour la médecine“.L’aboutissement de ce travail est la naissance d’un nouveau type de coils biologiquement actifs pour prévenir la recanalisation des anévrismes intracrâniens évalués grâce à des techniques d’imagerie conventionnelle et de microscopie avancée. Les résultats obtenus ont permis de déposer un brevet européen. Ces travaux nécessitent d’être confirmés par de nouvelles expérimentations dans un échantillon plus large d’animaux ainsi que l’analyse in vitro de la relation dose-effet potentielle. L'ensemble de ces travaux ne seront publiés qu'après la période de confidentialité nécessaire à l'évaluation du brevet dont la valorisation est en cours.
Aneurysms are rare in pediatric patients and despite a consensus that pediatric aneurysms are a different entity than adult aneurysms, the specifics of why and how they are different is not well understood. Unlike in adults, pediatric aneurysms are more common in males, more frequent in the posterior fossa, and more likely to be giant, dissecting, or otherwise complex. Aneurysms most commonly present with subarachnoid hemorrhage, but can also present with headache, neurologic deficit due to mass effect, or seizure. In this chapter, we will review the general characteristics of pediatric aneurysms, standard practices for medical management, and provide an update on surgical and endovascular management strategies.
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Keywords: MRA, CTA, Modality choice, Angiographic imaging, Mixed method Abstract Introduction: The aim of this study was to identify the decisive factors that influence the radiologist’s choice of vascular imaging modality. The radiographer is responsible for both performing the CTA or MRA procedure and for the justification of the exam. Therefore, knowledge about the rationale behind the choice of modality is relevant for the radiographer. Methods: This multimethod study included a survey from a national perspective and a literature review from a global perspective. The questionnaire was sent to radiologists working at public hospitals in Norway. The literature review included search in Pubmed, Web of Science and Scopus, with the keywords “MRA and CTA”, “MRA vs CTA” and “MRA and CTA and decision”. Results: A total of 38 radiologists responded to the survey and 21 articles were included in the literature review. Availability, patient situation, image quality and diagnostic value are important factors that are influencing the choice of modality. An important finding is that the choice of modality depends on the pathology and its location. The referring physician’s preference is also taken into consideration when choosing the modality. Choice of angiographic imaging modality: CTA vs. MRA Conclusion: The choice between the two modalities is usually based on the clinical indication and patient related factors. Factors related to the modality like radiation dose, examination time and availability also play a part but as technology quickly evolves it will also influence the imaging modality of choice. Guidelines can help to expand the radiographer's competence in evaluating the appropriateness of vascular imaging examinations.
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Background: Cerebral aneurysms in pediatrics represent < 4% of the total of this condition, and their rupture represents 10-23% mortality. Aneurysms have been associated with infections, head injuries, sickle cell anemia, cardiovascular diseases, autoimmune diseases, immunodeficiencies, and connective tissue diseases. Their clinical presentation includes severe headache, seizures, motor-sensory deficits, and death due to subarachnoid and intraparenchymal hemorrhage. Case report: We describe the case of a 12-year-old female patient who presented with a sudden intense headache; after 72 hours, generalized tonic-clonic seizures were observed. At the hospital, she was stabilized with antiepileptic drugs and analgesics. A simple head computed tomography scan showed intraparenchymal hemorrhage in the right frontal lobe and subarachnoid hemorrhage. The study was complemented with a cerebral angiotomography, which revealed an aneurysm of the anterior communicating artery. The pediatric neurosurgeon evaluated the case, and management in the pediatric intensive care unit was decided. Two weeks after the stroke, the aneurysm was clipped and excluded. The patient developed adequate clinical evolution and resolution of initial symptoms, resuming her daily activities. Conclusions: Pediatric cerebral aneurysms differ from their adult counterparts, mainly in their etiology and evolution. In addition, pediatric patients have a longer life expectancy. Aneurysm clipping and neurological endovascular therapy have shown similar results.
Objective Effect of long non-coding RNAs (lncRNAs) on intracranial aneurysm (IA) development has been identified, while the role of noncoding RNA activated by DNA damage (NORAD) in IA remains unexplored. We aimed to verify the impact of NORAD on IA through sponging microRNA-136-5p (miR-136-5p). Methods Ruptured and unruptured IAs were harvested from IA patients, and expression of NORAD, miR-136-5p, and KDM1A was determined. The vascular smooth muscle cells (VSMCs) were cultured and, respectively, transfected with altered NORAD, miR-136-5p, or lysine-specific demethylase 1 (KDM1A) to observe their effect on biological functions, as well as on contraction and synthesis-specific indices of VSMCs. Interactions between NORAD and miR-136-5p, and between miR-136-5p and KDM1A were confirmed. Results NORAD and KDM1A were upregulated while miR-136-5p was downregulated in IA, especially in ruptured IA. NORAD overexpression or miR-136-5p inhibition accelerated proliferation and migration, and decelerated phenotypic switching and apoptosis of VSMCs. The effects of overexpressed NORAD on VSMCs were reserved by miR-136-5p upregulation or KDM1A knockdown. NORAD functioned as a competing endogenous RNA of miR-136-5p and miR-136-5p targeted KDM1A. Conclusion NORAD suppressed miR-136-5p, thus upregulating KDM1A to participate in IA formation and rupture by inducing phenotypic regulation of VSMCs.
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Purpose: This meta-analysis is to comprehensively evaluate the diagnostic performance of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) for detecting intracranial aneurysm (IA). Methods: PubMed, Embase, Web of Science, and the Cochrane library were systematically searched for retrieving eligible studies. Study inclusion, data extraction, and risk of bias assessment were performed by two researchers independently. Pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated to assess the diagnostic value. In addition, heterogeneity and subgroup analysis were carried out. Results: In total, 18 studies comprising 3463 patients were selected. The results of 3D-TOF-MRA for diagnosing IA were SEN 0.89 (95% CI 0.82-0.94), SPE 0.94 (0.86-0.97), PLR 13.79 (5.92-32.12), NLR 0.11 (0.07-0.19), DOR 121.90 (38.81-382.94), and AUC 0.96 (0.94-0.98), respectively. In the subgroup analysis, studies without subarachnoid hemorrhage (SAH) tend to perform statistical significantly better (P < 0.05) in detecting IAs than studies with SAH 0.99 (0.98-1.00) vs. 0.89 (0.86-0.91). The diagnostic value of studies with a two-image reconstruction method was higher than studies with only one image reconstruction method: 0.99 (0.98-1.00) vs. 0.91 (0.89-0.94) with P < 0.05. The 3D-TOF-MRA had better SEN in aneurysms > 3 mm than the aneurysms ≤ 3 mm in diameter: 0.89 (0.87-0.92) vs. 0.78 (0.71-0.84) with P < 0.05. Conclusion: This study demonstrated that 3D-TOF-MRA has an excellent diagnostic performance for the overall assessment of IA and may serve as an alternative for further patient management with IA.
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Background: Retrospective studies have suggested that aneurysm morphology is a risk factor for subarachnoid hemorrhage (SAH). Objective: To investigate whether various morphological indices of unruptured intracranial aneurysms (UIAs) predict a future rupture. Methods: A total of 142 patients with UIAs diagnosed between 1956 and 1978 were followed prospectively until SAH, death, or the last contact. Morphological UIA indices from standard angiographic projections were measured at baseline and adjusted in multivariable Cox proportional hazards regression analyses for established risk factors for SAH. Results: During a follow-up of 3064 person-years, 34 patients suffered from an aneurysm rupture. In multivariable analyses, aneurysm volume, volume-to-ostium area ratio, and the bottleneck factor separately as continuous variables predicted aneurysm rupture. All the morphological indices were higher ( P < .01) after the rupture than before. In final multivariable analyses, current smoking (adjusted hazard ratio 2.50, 95% CI 1.03-6.10, P = .044), location in the anterior communicating artery (4.28, 1.38-13.28, P = .012), age (inversely; 0.95 per year, 0.91-1.00, P = .043), and UIA diameter ≥7 mm at baseline (2.68, 1.16-6.21, P = .021) were independent risk factors for a future rupture. Aneurysm growth during the follow-up was associated with smoking ( P < .05) and SAH ( P < .001), but not with the aneurysm indices. Conclusion: Of the morphological indices, UIA volume seems to predict a future rupture. However, as volume correlates with the maximum diameter of the aneurysm, it seems to add little to the predictive value of the maximum diameter. Retrospective studies using indices that are measured after rupture are of little value in risk prediction.
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MR angiography is proposed as a safer and less expensive alternative to the reference standard, DSA, in the follow-up of intracranial aneurysms treated with endovascular coil occlusion. We performed a systematic review and meta-analysis to evaluate the accuracy of TOF-MRA and contrast-enhanced MRA in detecting residual flow in the follow-up of coiled intracranial aneurysms. Literature was reviewed through the PubMed, Cochrane, and EMBASE data bases. In comparison with DSA, the sensitivity of TOF-MRA was 86% (95% CI: 82-89%), with a specificity of 84% (95% CI: 81-88%), for the detection of any recurrent flow. For contrast-enhanced MRA, the sensitivity and specificity were 86% (95% CI: 82-89%) and 89% (95% CI: 85-92%), respectively. Both TOF-MRA and contrast-enhanced MRA are shown to be highly accurate for detection of any recanalization in intracranial aneurysms treated with endovascular coil occlusion.
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Object: The purpose of aneurysm surgery is complete aneurysm obliteration while sparing associated arteries. Indocyanine green (ICG) videoangiography is a new technique that allows for real-time evaluation of blood flow in the aneurysm and vessels. The authors performed a retrospective study to compare the accuracy of ICG videoangiography with intraoperative angiography (IA), and determine if ICG videoangiography can be used without follow-up IA. Methods: From June 2007 through September 2009, 155 patients underwent craniotomies for clipping of aneurysms. Operative summaries, angiograms, and operative and ICG videoangiography videos were reviewed. The number, size, and location of aneurysms, the ICG videoangiography and IA findings, and the need for clip adjustment after ICG videoangiography and IA were recorded. Discordance between ICG videoangiography and IA was defined as ICG videoangiography demonstrating aneurysm obliteration and normal vessel flow, but post-IA showing either an aneurysmal remnant and/or vessel occlusion requiring clip adjustment. Results: Thirty-two percent of patients (49 of 155) underwent both ICG videoangiography and IA. The post-ICG videoangiography clip adjustment rate was 4.1% (2 of 49). The overall rate of ICG videoangiography-IA agreement was 75.5% (37 of 49) and the ICG videoangiography-IA discordance rate requiring post-IA clip adjustment was 14.3% (7 of 49). Adjustments were due to 3 aneurysmal remnants and 4 vessel occlusions. These adjustments were attributed to obscuration of the residual aneurysm or the affected vessel from the field of view and the presence of dye in the affected vessel via collateral flow. Although not statistically significant, there was a trend for ICG videoangiography-IA discordance requiring clip adjustment to occur in cases involving the anterior communicating artery complex, with an odds ratio of 3.3 for ICG videoangiography-IA discordance in these cases. Conclusions: These results suggest that care should be taken when considering ICG videoangiography as the sole means for intraoperative evaluation of aneurysm clip application. The authors further conclude that IA should remain the gold standard for evaluation during aneurysm surgery. However, a combination of ICG videoangiography and IA may ultimately prove to be the most effective strategy for maximizing the safety and efficacy of aneurysm surgery.
Background: The prevalence of asymptomatic unruptured intracranial aneurysms (AUIA) in a Southeast Asian population has not been previously studied. Knowing the disease burden and population at risk can assist us in making informed decisions when managing AUIAs. We aimed to determine if the local prevalence of AUIAs differed from other populations in the published literature. Methods: Magnetic resonance angiography radiology reports and images for 4572 patients between January 2013 and January 2014 were reviewed for AUIAs. Results: The overall prevalence of AUIAs was 3.5% (160/4572). It was significantly higher at 4.5% in women compared to 2.6% in men (P < 0.001). The mean aneurysm size was 3.2±1.7 mm. 88.5% (146/165) of the aneurysms measured less than 5 mm, 9.7% (16/165) measured 5 to 9 mm and 1.8% (3/165) measured more than 9 mm. The large majority of the aneurysms were located in the cavernous segment (72/165, 43.6%) and ophthalmic segment (34/165, 20.6%) of the internal carotid artery, followed by the middle cerebral artery (16/165, 9.7%). The posterior circulation contributed 9.1% (15/165) of the AUIAs. During the study period, one aneurysm ruptured and the rest of the aneurysms did not exhibit any growth in size. Conclusions: In this large cohort of Southeast Asian population, the prevalence of AUIA was 3.5%. Most of the AUIAs were less than 5 mm, and did not require intervention at time of discovery and did not progress within the year of follow-up.
The aim of this meta-analysis was to investigate the accuracy of subtraction computed tomography angiography (CTA) for diagnosing intracranial aneurysms. A systematic literature search up to January 1, 2013 was performed in PubMed. Two independent reviewers selected 8 studies that compared subtraction CTA with digital subtraction angiography. Data from the studies were used to construct a 2x2 contingency table on a per-patient basis in ≥5 diseased and 5 non-diseased patients, with additional data on a per-aneurysm basis. Overall, subtraction CTA had a pooled sensitivity of 99% [95% confidence interval (CI), 95-100%] and specificity of 94% (95% CI, 86-97%) for detecting and ruling out cerebral aneurysms, respectively, on a per-patient basis. On a per-aneurysm basis, the pooled sensitivity was 96% (95% CI, 90-99%), and the specificity was 91% (95% CI, 85-95%). In conclusion, subtraction CTA is a highly sensitive, specific and non-invasive method for the diagnosis and evaluation of intracranial aneurysms.
In 2003, the QUADAS tool for systematic reviews of diagnostic accuracy studies was developed. Experience, anecdotal reports, and feedback suggested areas for improvement; therefore, QUADAS-2 was developed. This tool comprises 4 domains: patient selection, index test, reference standard, and flow and timing. Each domain is assessed in terms of risk of bias, and the first 3 domains are also assessed in terms of concerns regarding applicability. Signalling questions are included to help judge risk of bias. The QUADAS-2 tool is applied in 4 phases: summarize the review question, tailor the tool and produce review-specific guidance, construct a flow diagram for the primary study, and judge bias and applicability. This tool will allow for more transparent rating of bias and applicability of primary diagnostic accuracy studies.
Background and purpose Follow-up of intracranial aneurysms treated by flow diverter with MRI is complicated by imaging artifacts produced by these devices. This study compares the diagnostic accuracy of three-dimensional time-of-flight MR angiography (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3 T for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment, with digital subtraction angiography (DSA) as the gold standard. Materials and methods Patients treated with flow diverters between January 2009 and January 2013 followed by MRA at 3 T (3D-TOF-MRA and CE-MRA) and DSA within a 48 h period were included in a prospective single-center study. Aneurysm occlusion was assessed with full and simplified Montreal scales and parent artery patency with three-grade and two-grade scales. Results Twenty-two patients harboring 23 treated aneurysms were included. Interobserver agreement using simplified scales for occlusion (Montreal) and parent artery patency were higher for DSA (0.88 and 0.61) and CE-MRA (0.74 and 0.55) than for 3D-TOF-MRA (0.51 and 0.02). Intermodality agreement was higher for CE-MRA (0.88 and 0.32) than for 3D-TOF-MRA (0.59 and 0.11). CE-MRA yielded better accuracy than 3D-TOF-MRA for aneurysm remnant detection (sensitivity 83% vs 50%; specificity 100% vs 100%) and for the status of the parent artery (specificity 63% vs 32%; sensitivity 100% vs 100%). Conclusions At 3 T, CE-MRA is superior to 3D-TOF-MRA for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment. However, intraluminal evaluation remains difficult with MRA regardless of the sequence used.
Stroke is the third leading cause of death and the leading cause of disability in contemporary society. Aneurysmal subarachnoid hemorrhage (aSAH) is a hemorrhagic stroke which accounts for 7% of all stroke cases and 22 to 25% of cerebrovascular deaths. Aneurysmal subarachnoid hemorrhage is a very complex disease and many controversies on its pathophysiology and management have not yet been settled. The aim of this review is to present the most recent evidence-based advances in the pathophysiology and perioperative management of aSAH.
The aim of this study was to prospectively assess the effect of low-tube voltage (80 kVp) 320-detector row volume computed tomographic (CT) angiography (L-VCTA) in the detection of intracranial aneurysms, with three-dimensional (3D) spin digital subtraction angiography (DSA) as the gold standard. Forty-eight patients with clinically suspected subarachnoid hemorrhages were divided into two groups. One group underwent L-VCTA and DSA, while the other group underwent conventional-tube voltage (120 kVp) volume CT angiography (C-VCTA) and DSA. Vascular enhancement, image quality, detection accuracy of aneurysms, and radiation dose were compared between the two groups. For objective image quality, the L-VCTA group had higher mean vessel attenuation, correlated with higher image noise and lower signal-to-noise ratio, than the C-VCTA group. For subjective image quality, there were no significant differences between the two groups regarding scores for arterial enhancement, depiction of small arterial detail, interference of venous structures, and overall image quality scores. The mean effective dose for the L-VCTA group was significantly lower than for the C-VCTA group (0.56 ± 0.25 vs 1.84 ± 0.002 mSv), with a reduction of radiation dose of 69.73%. With 3D DSA as the reference standard, the sensitivity, specificity, and accuracy in the L-VCTA and C-VCTA groups were 94.12%, 100%, 94.4% and 100%, 100%, and 100%, respectively. In both groups, there were significant correlations for maximum aneurysm diameter measurements between volume CT angiography and 3D DSA; no statistical difference in the mean maximum diameter of each aneurysm was measured between volume CT angiography and 3D DSA. L-VCTA is helpful in detecting intracranial aneurysms, with results similar to those of 3D DSA, but at a lower radiation dose than C-VCTA.