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One aneurysm in the right cavernous segment of internal carotid artery in 40-year-old man. (a) Volume-rendered digital subtraction CT angiographic image shows the aneurysm in the right cavernous segment of internal carotid artery (arrow). (b) Volume-rendered image without bone subtraction shows part of the aneurysm covered by the adjacent skull (arrow). (c) Contrast-enhanced maximum intensity projection with bone subtraction shows the aneurysm in right internal carotid artery (arrow). (d) Three-dimensional DSA image of the aneurysm (arrow).
Source publication
To evaluate the diagnostic accuracy of digital subtraction computed tomographic (CT) angiography in the detection of intracranial aneurysms compared with three-dimensional (3D) rotational digital subtraction angiography (DSA), as reference standard, in a large cohort in a single center.
The study was waived by the institutional review board because...
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Background and purpose:
Invasive cerebral DSA has largely been replaced by CTA, which is noninvasive but has a compromised arterial view due to superimposed bone and veins. The purpose of this study was to evaluate whether arterial visualization in CTPa is superior to standard CTA, which would eliminate the need for an additional CTA scan to asses...
Objective Despite the technological advancement in imaging, digital subtraction angiography (DSA) remains gold standard imaging modality for spontaneous subarachnoid hemorrhage (SAH). But even after DSA, around 15% of SAH remains elusive for the cause of the bleed. This is an institutional review to solve the mystery, “when is second DSA really ind...
Residual aneurysm after microsurgical clipping carries a risk of aneurysm growth and rupture. Digital subtraction angiography (DSA) remains the standard to determine the adequacy of clipping. Intraoperative indocyanine green (ICG) angiography is increasingly utilized to confirm optimal clip positioning across the neck and to evaluate the adjacent v...
BACKGROUND
The current gold standard for evaluation of the surgical result after intracranial aneurysm (IA) clipping is two-dimensional (2D) digital subtraction angiography (DSA). While there is growing evidence that postoperative 3D-DSA is superior to 2D-DSA, there is a lack of data on intraoperative comparison.
OBJECTIVE
To compare the diagnosti...
p> Background & Objectives: The Previous studies of multidetector CT (MDCT) of the lower extremities for the detection of peripheral vascular disease showed high diagnostic accuracy but were performed with older generation systems. Our study aimed at assessing the diagnostic value of 128 MDCTA compared with that of digital subtraction angiography (...
Citations
... However, for aneurysms < 4-mm multidetector arrays are significantly better with a sensitivity of 92% compared 75% for a single array [30]. Other series looking at small aneurysms < 3 mm report a sensitivity falling to 86-92% [31][32][33]. While sub-3-mm aneurysms have a lower rupture risk and are unlikely to be treated, a false negative still has implications for decisions on further surveillance imaging for the patient. ...
The treatment of intracranial aneurysms is dictated by its risk of rupture in the future. Several clinical and radiological risk factors for aneurysm rupture have been described and incorporated into prediction models. Despite the recent technological advancements in aneurysm imaging, linear length and visible irregularity with a bleb are the only radiological measure used in clinical prediction models. The purpose of this article is to summarize both the standard imaging techniques, including their limitations, and the advanced techniques being used experimentally to image aneurysms. It is expected that as our understanding of advanced techniques improves, and their ability to predict clinical events is demonstrated, they become an increasingly routine part of aneurysm assessment. It is important that neurovascular specialists understand the spectrum of imaging techniques available.
... Although it is well known that CT angiography is less sensitive than Digital Subtraction Angiography (DSA), which remains the gold standard, it is generally accepted that the CTA is highly accurate in the diagnosis of intracranial aneurysms. Comparison studies between CTA and DSA for the detection and evaluation of intracranial aneurysms find that CTA is highly sensitive, and specific and can be used as an alternative to DSA [11,12]. ...
Intracranial aneurysms are common conditions that are usually asymptomatic and found incidentally, yet they can rupture and lead to subarachnoid hemorrhage, in addition to causing mass effects, especially with larger aneurysms. Bilateral supraclinoid aneurysms are extremely rare and were reported in only two instances. These aneurysms can cause a range of symptoms and require careful management. We present the case of a 42-year-old man with no concomitant medical conditions who presented with a persistent headache and deteriorating visual acuity over time. Neurological examination was unremarkable. Connective tissue diseases were ruled out by clinical and laboratory testing. Bilateral large, partly thrombosed supraclinoid segment fusiform aneurysms of the internal carotid artery that are causing midbrain compression and obstructive hydrocephalus were shown by brain CT, CT angiography, MRI, and MR angiography (MRA). Both surgery and endovascular treatment were denied by the patient. However, a ventriculoperitoneal shunt was placed in an outside center and relieved the patient's symptoms. The patient is being followed up. In conclusion, bilateral giant aneurysms of the internal carotid artery present unique challenges and can lead to various clinical manifestations and effects on surrounding structures. In this case, we reported the first instance of obstructed hydrocephalus caused by the largest bilateral supraclinoid carotid aneurysms.
... DSA CT angiography should be the preferred noninvasive modality to evaluate the case of CVT. 16 In our case, DSA was suggestive of bilateral dural arteriovenous fistula with multiple collaterals. Besides neuroimaging, American Heart Association recommends obtaining complete count (CBC), chemistry panel, prothrombin time, and activated partial thromboplastin time for the suspected patient. 1 Investigation may reveal a hypercoagulable state, infection, and inflammatory process. ...
Key Clinical Message
Clinicians should consider central venous thrombosis (CVT) as a differential diagnosis in young adolescents with persistent headaches. It is essential to assess for concurrent CVT and dural arteriovenous fistula (DAVF), particularly in those with a history of CVT.
Abstract
Cerebral venous thrombosis (CVT) and dural arteriovenous fistula (DAVF) are uncommon vascular disorders with diverse clinical presentations. The coexistence of CVT and DAVF is a rare but important association that may impact the management and prognosis of affected patients. Prothrombotic conditions generally ranging from acquired to genetic, oral contraceptives, malignancy, puerperium, infection, and head injury are the common risk factors for cerebral venous thrombosis. Here, we present a case of 18 years males who developed recurrent cerebral thrombosis on the background of the presence of an arteriovenous fistula.
... Computed tomography angiography (CTA) is a noninvasive method for visualization of the OA, and it can display the complex course of the OA. 9 In this study, morphological parameters of the ICA and the OA were measured by reconstructing three-dimensional (3D) models using computer software that has been used for the observation and morphological analysis of small arteries, [10][11][12][13] and which can reflect the actual state of blood vessels in vivo. ...
Purpose:
To investigate the morphological characteristics of the ophthalmic artery (OA) and retinal vessels in ocular ischemic syndrome (OIS) and to compare their ability to identify OIS.
Methods:
This cross-sectional observational study included 21 patients with unilateral OIS and 17 controls matched for age, sex, degree of internal carotid artery (ICA) stenosis, and cerebral collateral patency. This study used a three-dimensional reconstruction based on computed tomographic angiography to measure the morphological characteristics of the OA and the ICA. Quantitative measurements of retinal vessel diameter were performed using the Integrative Vessel Analysis software. Receiver operating characteristic (ROC) curve analysis was performed to assess the ability of the OA diameter and the central retinal artery equivalent (CRAE) to identify OIS.
Results:
The diameter of the OA (odds ratio = 0.001; P = 0.001) and the CRAE (odds ratio = 0.951; P = 0.028) were significantly associated with the presence of OIS after adjusting for age, sex, and the degree of the ICA stenosis. The areas under the curve for the OA diameter and the CRAE were, respectively, 0.871 (P < 0.001) and 0.744 (P = 0.017) according to the ROC curves analysis.
Conclusions:
The OA diameter measurement identified OIS better than CRAE measurement. The OA may reflect the changes in ocular blood supply in patients with OIS earlier than retinal vessels. The OA of eyes with OIS may undergo arterial wall remodeling, leading to a decrease in OA diameter and further reduction in blood flow.
... 9 Lu et al found that digital subtraction angiogram had a sensitivity of 91.3% of detecting aneurysms less than 3 millimeters (mm); 94.0% for aneurysms between 3 mm but <5 mm; 98.4% for aneurysms between 5 mm and <10 mm; and 100% for aneurysms ≥10 mm. 10 This case highlights the importance of the above evaluation with regard to sentinel headaches. Sentinel headaches signify a particularly severe headache that precedes a second episode of a profound headache secondary to intracranial aneurysm rupture. ...
Introduction:
Radiologically negative subarachnoid hemorrhage (SAH) has a low incidence and is associated with good clinical outcomes.
Case report:
We present the case of a 44-year-old male with new-onset headaches, which began one week prior while bike riding. At an outside hospital, he had normal computed tomography head and angiogram. He declined a lumbar puncture. Over the following week, the headache was persistent. He lacked meningeal signs. Repeat studies were normal. Lumbar puncture was positive for xanthochromia.
Conclusion:
Radiologically negative SAH should be included in the differential diagnosis of patients presenting with unremitting headache in the setting of recent exercise, despite negative imaging, and meningeal signs.
... 8,9 The majority of data in the literature showed that CTA has a good diagnostic efficiency which is comparable to DSA with a high sensitivity, specificity and accuracy of 95% -98%, 90% -100% and 94% -98%, respectively. 10,11,12,13 Meta-analyses of up to 50 studies stated similar findings with pooled sensitivities and specificities of 97% -98% and 98% -100%, respectively. 8,9 A few studies demonstrated lower CTA diagnostic performance with overall sensitivity of 71% -89% and accuracy of 74% -90%. ...
... The vast majority of previous studies in the literature showed good CTA diagnostic performance that is comparable to DSA. 8,9,10,11,12,13,17 This is contrary to our study, which showed lower CTA performance than previous reports. The compromised diagnostic performance of CTA in our study was related to unexpectedly high false negative and false positive CTA results in 19 and 12 patients, respectively. ...
... These factors were also considered and acknowledged by other authors. 15,16,17 Good CTA performance reported in the literature may be because of optimal reading conditions by at least two experienced neuro-radiologists reading CTA and DSA images either individually or in consensus 11,12,13,17 and consistent use of post processing tools and techniques. Some studies used a probability scale for the level of confidence in diagnosing the aneurysms on CTA. ...
Background:
Digital subtraction angiography (DSA) is invasive, costly and unavailable in many South African hospitals; however, it remains the gold standard for imaging intracranial aneurysms. CT angiography (CTA) is a non-invasive and readily available screening tool prior to DSA.
Objectives:
This study aimed to evaluate the diagnostic performance of CTA in detecting ruptured intracranial aneurysms using DSA as the reference standard and to determine the effect of aneurysm size and location on CTA sensitivity.
Method:
A retrospective analysis of CTA and DSA data from reports of patients suspected to have aneurysmal subarachnoid haemorrhage (SAH) at Chris Hani Baragwanath Academic Hospital between January 2017 and June 2020.
Results:
Conventional DSA detected aneurysms in 94 out of 115 patients; while of these, CTA detected 75 and missed 19. The CTA sensitivity, specificity and accuracy was 80%, 43% and 73%, respectively. The CTA sensitivity for aneurysms < 3 mm and 3 mm - 5 mm in size was 30% and 81.5%, respectively (p = 0.024). Sensitivity of CTA for posterior communicating artery (PComm) aneurysms was 56% and lower than other major anterior circulation locations (83% - 91%) (p = 0.045).
Conclusion:
The CTA diagnostic efficiency was lower than previously reported, with even lower sensitivity for aneurysms < 3 mm and for those arising from the PComm. Thus, CTA should remain a screening tool prior to DSA in all local patients suspected to have aneurysmal SAH.
Contribution:
Larger, prospective studies are required to accurately define the role of CTA in diagnosing intracranial aneurysms in a developing country with limited resources.
... Human studies and further investigation into the pathway of the gut microbiome's role in cerebral aneurysm formation are required before bacterial biomarkers can be used to detect aneurysm formation (Fig. 3). (Keedy 2006) 87 95 3D DSA (Lu et al. 2012) 97.8 88.7 ...
Intracranial aneurysms are reported to affect 2–5% of the population. Despite advances in the surgical management of this disease, diagnostic technologies have marginally improved and still rely on expensive or invasive imaging procedures. Currently, there is no blood-based test to detect cerebral aneurysm formation or quantify the risk of rupture. The aim of this review is to summarize current literature on the mechanism of aneurysm formation, specifically studies relating to inflammation, and provide a rationale and commentary on a hypothetical future blood-based test. Efforts should be focused on clinical-translational approaches to create an assay to screen for cerebral aneurysm presence and risk-stratify patients to allow for superior treatment timing and management.
Graphical Abstract
Cerebral Aneurysm Blood Test Considerations: There are multiple caveats to development of a putative blood test to detect cerebral aneurysm presence.
... Early detection of cerebral aneurysms is most important in preventing subarachnoid hemorrhage (SAH). Computed tomography angiography (CTA) is a well-established technique used to detect this disease accurately and cost-effectively, compared with conventional digital subtraction angiography (DSA) and magnetic resonance angiography (MRA) in various clinical imaging applications [1,2]. Invasive three-dimensional (3D) DSA is the gold standard for detection of cerebral aneurysms. ...
... Conventionally, cerebral CTA can be classified into two types: (1) non-subtraction CTA (NS-CTA) and (2) bone subtraction CTA (BS-CTA) [3,8]. NS-CTA is performed using the multidetector-row CT when injecting the contrast agent, whereas BS-CTA requires twice CT scan with and without the injection of contrast medium under the same conditions. ...
... Nevertheless, it is susceptible to motion artefacts due to the long scan times required and higher scan costs compared with CTA [6,7]. Conventionally, cerebral CTA can be classified into two types: (1) non-subtraction CTA (NS-CTA) and (2) bone subtraction CTA (BS-CTA) [3,8]. NS-CTA is performed using the multidetector-row CT when injecting the contrast agent, whereas BS-CTA requires twice CT scan with and without the injection of contrast medium under the same conditions. ...
The purpose of this study was to investigate the viability of the proposed method in preventing the loss of metallic components including the clip and coil in cerebral computed tomography angiography (CTA). Forty patients undergoing surgery for aneurysms carried metallic materials. The proposed method is based on conventional bone subtraction CTA (BS-CTA) system. Briefly, the position of metal components was determined using the threshold value and a region of interest (ROI). An appropriate threshold was used to separate the background from the target materials based on the Otsu method. A three-dimensional (3D) rendering was performed from the proposed BS-CTA data carrying the extracted target information. The accuracy of clip and coil region measured using the dice similarity coefficient (DSC) and bidirectional Hausdorff distance (HD) is reported. The metallic components of the proposed BS-CTA were significantly visualized in various patient cases. Quantitative evaluation using the proposed method is based on the mean DSC of 0.93 with a standard deviation (SD) of ±0.05 (e.g., maximum value = 0.99, minimum value = 0.75, 95% confidence interval (CI) = 0.91 to 0.95, and all p < 0.05). The mean HD was 1.50 voxels with an SD of ± 0.58 (e.g., maximum value = 5.95, minimum value = 0.12, 95% CI = 1.10 to 1.90, and all p < 0.05). The proposed method demonstrates effective segmentation of the metallic component and application to the existing conventional BS-CTA system.
... Neurosurgeons are frequently faced with the need to interpret brain CTA, especially in emergency settings when angiography is limited. CTA has proven to be useful for the detection of intracranial aneurysms larger than 3 mm [30]. Because of its less invasive neurovascular imaging modality, availability, cost-effectiveness and ability to be performed quickly, it has become the first-line choice for subarachnoid hemorrhage in many institutions. ...
... The most important limitation of CTA is the inability to visualize very small vessels, including the ophthalmic, superior hypophyseal, AChA and perforators. Li Lu et al. reported inferior spatial resolutions of CTA (0.6 mm), compared to those of DSA (0.32 mm) [30]. Neither is it possible to obtain information regarding flow rates or collateral circulation using standard CTA sequences. ...
The study of cerebrovascular anatomy can be difficult and may take time due to its intrinsic complexity. However, it can also be difficult for the following reasons: the excessive description of neuroanatomy making articles hard to read, the unclear clinical application of what is written, the use of simplified or intricate schematic drawings that are not always appropriate for effective teaching, the poor quality of neuroanatomy dissections and the use of unusual views of figures that are not strictly related to the most frequent neuroimages to be interpreted in daily practice. Because of this, we designed an article that incorporates original and accurate anatomical dissections in an attempt to improve its comprehensibility. Five formalin-fixed adult cadaveric heads, whose vessels were injected with a colored silicone mixture (red for arteries and blue for veins), were dissected and examined under a microscope with magnifications from 3× to 40×. Special emphasis has been placed on correlating topographic anatomy with routine neuroimaging studies from computed tomographic angiography (CTA) and digital subtraction angiography (DSA). The essential surgical anatomy in a neurosurgeon’s daily practice is also described. The cadaveric dissections included in this study contribute to the understanding of the cerebrovascular anatomy necessary for the neurosurgeon’s daily practice.
... Briefly, DSA procedures were conducted with the Axiom Artis Zee (Siemens Healthcare, Erlangen, Germany) or the Allura Xper FD 20/20 (Philips Medical Systems, Best, The Netherlands) with standard injection protocols as described previously [5]. Post-processing of the 3D-DSA was conducted in an independent workstation equipped with InSpace 3D software [11][12][13]. The study design was listed on Clinical Research Information Service (registration number KCT0005084) prior to initiation of the study. ...
Auto-detection of cerebral aneurysms via convolutional neural network (CNN) is being increasingly reported. However, few studies to date have accurately predicted the risk, but not the diagnosis itself. We developed a multi-view CNN for the prediction of rupture risk involving small unruptured intracranial aneurysms (UIAs) based on three-dimensional (3D) digital subtraction angiography (DSA). The performance of a multi-view CNN-ResNet50 in accurately predicting the rupture risk (high vs. non-high) of UIAs in the anterior circulation measuring less than 7 mm in size was compared with various CNN architectures (AlexNet and VGG16), with similar type but different layers (ResNet101 and ResNet152), and single image-based CNN (single-view ResNet50). The sensitivity, specificity, and overall accuracy of risk prediction were estimated and compared according to CNN architecture. The study included 364 UIAs in training and 93 in test datasets. A multi-view CNN-ResNet50 exhibited a sensitivity of 81.82 (66.76–91.29)%, a specificity of 81.63 (67.50–90.76)%, and an overall accuracy of 81.72 (66.98–90.92)% for risk prediction. AlexNet, VGG16, ResNet101, ResNet152, and single-view CNN-ResNet50 showed similar specificity. However, the sensitivity and overall accuracy were decreased (AlexNet, 63.64% and 76.34%; VGG16, 68.18% and 74.19%; ResNet101, 68.18% and 73.12%; ResNet152, 54.55% and 72.04%; and single-view CNN-ResNet50, 50.00% and 64.52%) compared with multi-view CNN-ResNet50. Regarding F1 score, it was the highest in multi-view CNN-ResNet50 (80.90 (67.29–91.81)%). Our study suggests that multi-view CNN-ResNet50 may be feasible to assess the rupture risk in small-sized UIAs.
