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Discrepancy between two-dimensional and three-dimensional digital subtraction angiography for the planning of endovascular coiling of small cerebral aneurysms
Abstract
Background
To investigate the discrepancy between two-dimensional digital subtraction angiography and three-dimensional rotational angiography for small (<5 mm) cerebral aneurysms and the impact on decision making among neuro-interventional experts as evaluated by online questionnaire.
Materials and methods
Eight small (<5 mm) ruptured aneurysms were visually identified in 16 image sets in either two-dimensional or three-dimensional format for placement in a questionnaire for 11 invited neuro-interventionalists. For each set, two questions were posed: Question 1: “Which of the following is the preferred treatment choice: simple coiling, balloon remodeling or stent assisted coiling?”; Question 2: “Is it achievable to secure the aneurysm with pure simple coiling?” The discrepancies of angio-architecture parameters and treatment choices between two-dimensional-digital subtraction angiography and three-dimensional rotational angiography were evaluated.
Results
In all eight cases, the neck images via three-dimensional rotational angiography were larger than two-dimensional-digital subtraction angiography with a mean difference of 0.95 mm. All eight cases analyzed with three-dimensional rotational angiography, but only one case with two-dimensional-digital subtraction angiography were classified as wide-neck aneurysms with dome-to-neck ratio < 1.5. The treatment choices based on the two-dimensional or three-dimensional information were different in 56 of 88 (63.6%) paired answers. Simple coiling was the preferred choice in 66 (75%) and 26 (29.6%) answers based on two-dimensional and three-dimensional information, respectively. Three types of angio-architecture with a narrow gap between the aneurysm sidewall and parent artery were proposed as an explanation for neck overestimation with three-dimensional rotational angiography.
Conclusions
Aneurysm neck overestimation with three-dimensional rotational angiography predisposed neuro-interventionalists to more complex treatment techniques. Additional two-dimensional information is crucial for endovascular treatment planning for small cerebral aneurysms.
... e imaging of DSA is intuitively clear; less contrast medium is used, a small amount of X-ray radiation and even small vessels can be clearly displayed. However, the disadvantage of DSA is that the field of view is small [24,25]. Starting from the two aspects of structural information and temporal information, the phase of cerebrovascular DSA was automatically identified for the first time. ...
This study is aimed at exploring the diagnostic value of digital subtraction angiography (DSA) based on faster region-based convolutional networks (Faster-RCNN) deep learning for maintenance hemodialysis (MHD) diseases and to provide a theoretical basis for clinical nursing. A total of 50 MHD patients who were clinically diagnosed in the Blood Purification Center were randomly divided into the control group and the experimental group (25 cases for each group). The control group was given routine nursing intervention, and the experimental group was given overall nursing intervention under the supervision of DSA. A faster RCNN multitarget detection network was constructed to analyze the average accuracy of various vascular structures in the test set. The self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to evaluate the degree of anxiety and depression. The urine volume before and after the operation, local hematoma after a puncture, the incidence of complications, and nursing satisfaction were recorded. The results showed that the average accuracy of the vein, internal carotid artery, circle of Willis, venous sinus, and venous vessels was 0.876, 0.916, 0.994, 0.925, and 0.732, respectively. The success rate of surgery in the experiment group was higher than that in the control group, and the difference had statistical significance (P
... images. The literature has demonstrated that neck width measurements are calculated larger than normal in 3D images [3,[21][22][23]. In order to accurately evaluate the neck region, it is thought that taking measurements from specially taken 2D images in the angle detected in 3D images and in which the neck region is most clearly visualized will yield the most accurate result. ...
Background/aim:
In this study, we aimed to investigate what should be considered as potential determinants of treatment strategies when evaluating 3D DSA images.
Material and methods:
Our inclusion criteria were as follows: (1) presence of at least one intracranial aneurysm demonstrated by conventional angiography, (2) having both 2D and 3D images (3) aged over 18 years old. First two-dimensional (2D), then 3D angiography images of 226 aneurysms of 150 patients were scanned. Morphological characteristics such as size, configurations, relationship with parent artery, baby counts, and other incidental findings, were determined.
Results:
Of the 226 aneurysms, 11 (4.9%) were only detected on 3D images. Four of these 11 additional aneurysms were believed to be babies of other aneurysms seen in 2D images. Middle cerebral artery (MCA) M1 segment was the most common localization in terms of missed aneurysms. Of the 28 aneurysms located in the communicating segment of the internal carotid artery (ICA), absolute location of 7 (25%) could not be detected in 2D images or were found in the wrong location. Of the 24 aneurysms located in the ophthalmic segment, the origin of 8 (33%) could not be clearly identified in 2D images. Truncus relationships of middle cerebral arteries (MCA) bifurcation/trifurcation aneurysms were seen in 41 of 63 aneurysms (65%) on 2D images whereas all were confirmed on 3D images. Fenestrations not seen in 2D images were identified in 3D images of 4 patients (3%).
Conclusion:
The superiority of 3D images compared to 2D images in determining the morphologic characteristics of intracranial aneurysms has been known for a long time. The contribution of 3D images to the treatment can be summarized as evaluating the parent artery relationship, revealing the number and shapes of aneurysm babies more clearly, detecting fenestrations, and shortening procedure time by finding the correct working angle.
Characterization of the rupture risk factors for small intracranial aneurysms (SIAs, ≤5 mm) is clinically valuable. The present study aims to identify image-based morphological parameters and anatomical locations associated with the rupture status of SIAs. Two hundred and sixty-three patients with single SIAs (128 ruptured, 135 unruptured) were included, and six morphological parameters, including size, aspect ratio (AR), size ratio (SR), height-width ratio (H/W), flow angle (FA) and aneurysm width-parent artery diameter ratio, and the aneurysm locations were evaluated using three-dimensional geometry, and were used to identify a correlation with aneurysm rupture. Statistically significant differences were observed between ruptured and unruptured groups for AR, SR, H/W, FA, and aneurysm locations, from univariate analyses. Logistic regression analysis further revealed that AR (p = 0.034), SR (p = 0.004), H/W (p = 0.003), and FA (p < 0.001) had the strongest independent correlation with ruptured SIAs after adjustment for age, gender and other clinical risk factors. A future study on a larger SIA cohort need to establish to what extent the AR, SR, H/W and FA increase the risk of rupture in patients with unruptured SIAs in terms of absolute risks.
Background:
Prospective studies of unruptured aneurysms have shown very low rates of rupture for small aneurysms (<10 mm) and suggested that the risk of treatment outweighs benefit. However, common clinical practice shows that patients with aneurysmal subarachnoid hemorrhage (aSAH) frequently have small aneurysms.
Objective:
To investigate trends in size and location of ruptured aneurysms over a 25-yr period.
Methods:
A prospective, Institutional Review Board-approved database of all patients presenting to our institution with aSAH from 1991 to 2016 was analyzed. Cerebral angiography identified the source of hemorrhage. Patients with nonaneurysmal etiologies were excluded.
Results:
Complete data were available for 1306/1562 patients (84%) with aSAH from 1991 to 2016. The average age was 53 yr and 72% of patients were female. The average size of ruptured aneurysms over 25 yr was 8.0 mm. The average size of ruptured aneurysms decreased steadily with each 5-yr interval from 10.1 mm (1991-1996) to 6.6 mm (2012-2016; P < .001). Overall, very small aneurysms (<5 mm) were responsible for aSAH in 41% of patients. The percentage of very small ruptured aneurysms rose from 29% during the initial 5-yr period (1991-1996) to 50% in the most recent period. Likewise, the percentage of ruptured aneurysms that were 5 to 9 mm rose from 26% to 34% (P < .001). In the past 5 yr, aneurysms <10 mm accounted for 84% of aSAH. Vessel of origin (P = .097) and aneurysm location (P = .322) did not vary with time.
Conclusion:
Ruptured small and very small aneurysms represent a majority and increasing share of aSAH. Identification and prophylactic treatment of these aneurysms remains an important clinical role for cerebrovascular neurosurgery.
Background and purpose:
Outcomes of endovascular treatment of very small intracranial aneurysms are still not well-characterized. Recently, several series assessing coil embolization of tiny aneurysms have presented new promising results. Thus, we performed a systematic review and meta-analysis of studies evaluating endovascular treatment of very small intracranial aneurysms.
Materials and methods:
We conducted a computerized search of Scopus, Medline, and the Web of Science for studies on endovascular treatment of very small (≤3 mm in diameter) intracranial aneurysms published between January 1996 and May 2015. Using a random-effects model, we evaluated clinical and angiographic outcomes.
Results:
Twenty-two studies with 1105 tiny aneurysms (844 ruptured and 261 unruptured) endovascularly treated were included. Postoperative and long-term complete occlusion was achieved in 85% (95% CI, 78%-90%) and 91% (95% CI, 87%-94%) of aneurysms, respectively. The recanalization rate was 6% (95% CI, 4%-11%) and retreatment occurred in 7% (95% CI, 5%-9%) of cases. Seventy-nine percent (95% CI, 64%-89%) of patients had good neurologic outcome at long-term follow-up. Intraprocedural rupture occurred in 7% (95% CI, 5%-9%) of the coiling procedures, while thromboembolic complications occurred in 4% (95% CI, 3%-6%).
Conclusions:
Coil embolization of very small intracranial aneurysms can be performed safely and effectively. In the case of unruptured aneurysms, procedure-related complications are not negligible. Patients and providers should consider such risks when engaged in a shared decision-making process.
Background and purpose:
The use of stents in the setting of SAH is controversial because of concerns about the efficacy and risk of dual antiplatelet therapy. We compare complications of stent-assisted coil embolization in patients with acutely ruptured aneurysms with complications in patients with unruptured aneurysms.
Materials and methods:
Between February 2007 and March 2015, 45 acutely ruptured aneurysms and 47 unruptured aneurysms were treated with stent-assisted coiling. Patients with ruptured aneurysms were not pretreated with antiplatelet medication but received intravenous aspirin during the procedure. Thromboembolic events and early rebleeds were recorded.
Results:
In ruptured aneurysms, 9 of 45 patients had thromboembolic complications. Four patients remained asymptomatic, 4 developed infarctions, and 1 patient died. The permanent complication rate in ruptured aneurysms was 11% (95% CI, 4%-24%). Five of 45 patients (11%; 95% CI, 4%-24%) had an early rebleed from the treated aneurysm after 3-45 days, and in 4, this rebleed was fatal. In 46 patients with 47 unruptured aneurysms, thromboembolic complications occurred in 2. One patient remained asymptomatic; the other had a thalamus infarction. The complication rate in unruptured aneurysms was 2.2% (1 of 46; 95% CI, 0.01%-12%). No first-time hemorrhages occurred in 46 patients with 47 aneurysms during 6 months of follow-up.
Conclusions:
The complication rate of stent-assisted coiling with early adverse events in ruptured aneurysms was 10 times higher than that in unruptured aneurysms. Early rebleed accounted for most mortality. In ruptured aneurysms, stent-assisted coil embolization is associated with increased morbidity and mortality and should only be considered when less risky options have been excluded.
Wide-neck intracranial aneurysms were originally thought to be either untreatable or very challenging to treat by endovascular means because of the risk of coil protrusion into the parent vessel. The introduction of the balloon remodeling technique (BRT) and later stents specifically designed for intracranial use has progressively allowed these lesions to be endovascularly treated. BRT and stent-assisted coiling technique (SACT) were first designed to treat sidewall aneurysms but, with gained experience and further technical refinement, bifurcation complex-shaped wide-neck aneurysms have been treated by coiling enhanced by BRT and SACT. In this article, we will review and describe the inherent benefits and drawbacks of BRT as well as SACT.
Background and purpose:
Stent-assisted coiling has expanded the treatment of intracranial aneurysms. With the use of continuously compiled data, we reviewed the role and drawbacks of stent-assisted coiling.
Materials and methods:
We compiled data from consecutive patients from 2003-2012 who underwent coiling, with or without stent assistance. Clinical and angiographic results were analyzed retrospectively.
Results:
Of 1815 saccular aneurysms in 1505 patients, 323 (17.8%) were treated with stents (299 procedures) and 1492 (82.2%) without stents (1400 procedures). Procedure-related complications occurred in 9.4% with stents versus 5.6% without stents (P = .016, relative risk 1.5; 95% CI, 1.1-2.7). Ischemic complications were more frequent in the stent group than in the no-stent group (7.0% versus 3.5%; P = .005; relative risk, 1.7; 95% CI 1.2-2.5), as were hemorrhagic complications (2.3% versus 1.9%, P = .64). Procedure-induced mortality occurred in 2.7% (8/299) with stents versus 1.1% (15/1400) without stents (P = .029; relative risk, 2.0; 95% CI, 1.1-3.5). Logistic regression analysis identified wide-neck aneurysms as the most significant independent predictor of complications. A total of 64.1% (207/323) of aneurysms treated with stents and 70.3% (1049/1492) treated without stents have been followed, disclosing angiographic recurrence in 15.5% (32/207) versus 35.5% (372/1049), respectively (P < .0001). Logistic regression analysis showed that the presence of a stent was the most important factor for the reduction of angiographic recurrence (P < .0001; relative risk, 2.3; 95% CI, 1.6-3.3).
Conclusions:
The stent-assisted coiling technique is associated with a significant decrease in recurrences but a significant increase in complications. The treatment of wide-neck aneurysms remains hazardous.
Background and purpose:
Stent-assisted coil embolization has become one of the most preferred techniques in the treatment of wide-neck intracranial aneurysms; however, long-term patency and safety of the self-expanding neurostents and their role in durability of the endovascular treatment has remained ambiguous. We sought to retrospectively examine the long-term results of self-expanding stent usage in conjunction with coil embolization in treatment of wide-neck cerebral aneurysms.
Materials and methods:
We coiled 500 wide-neck cerebral aneurysms with different types of self-expanding neurostent assistance in 468 patients. Patient and aneurysm characteristics, pharmacologic therapy protocol, complications, and initial occlusion grades were analyzed. Patients underwent angiographic follow-up at 6 months to 7 years after treatment. DSA or MRA images of all patients were analyzed to assess the occlusion rate of aneurysms and patency of the parent artery.
Results:
Enterprise (n = 340), Solitaire (n = 98), Wingspan (n = 41), LEO (n = 16), and Neuroform (n = 5) stent systems were used in this series. Stent-related thromboembolic events occurred in 21 patients and intraoperative rupture occurred in 4 patients. Initially, complete occlusion was achieved in 42.2% of the aneurysms, and, according to the last follow-up data, the rate had progressed to 90.8%. Recanalization rate at 6 months was 8%, whereas the late recanalization rate was 2%.
Conclusions:
The use of stents in endovascular treatment provides high rates of complete occlusion and low rates of recurrence at a long-term follow-up study.
Background and purpose:
3DRA is considered the reference standard for the assessment of intracranial aneurysm morphology. However, it has been shown that 3DRA may overestimate neck size compared with 2D DSA. The purpose of this study was to determine the impact of neck size overestimation with 3DRA on intra-aneurysmal hemodynamics.
Materials and methods:
In a series of 20 patients, 20 intracranial aneurysms were analyzed for aneurysm neck size overestimation with 3DRA compared with 2D DSA. 3DRA-derived vascular models were modified to agree with 2D DSA. Geometric and hemodynamic variables of the original and modified vascular models were compared.
Results:
In 8 of the 20 evaluated cases, 3DRA-derived aneurysm models showed neck size overestimation compared with 2D DSA images. The average neck diameter reduction after modification was 19%, which was, on average, 0.85 mm (±0.32 mm). Modification of the neck resulted in differences in location of inflow jet (2/8), impingement zone (3/8), and low WSS area (4/8). In 1 case, the maximal WSS increased by 98% after modification. The change of impingement zone location resulted in a different classification of the impingement zone region in 2 cases.
Conclusions:
Neck size overestimation on 3DRA can have non-negligible consequences for hemodynamic features determined with CFD.
The aim of this study was to compare conventional two-dimensional (2D) digital subtraction angiography (DSA) with three-dimensional (3D) rotational DSA in the investigation of intracranial aneurysm in terms of detection, size measurement, neck diameter, neck delineation, and relationship with surrounding vessels. A further aim was to compare radiation dose, contrast volume, and procedural time between the two protocols.
Thirty-five patients who presented with subarachnoid bleeds on computed tomography and were suspected of having intracranial aneurysms underwent conventional 2D DSA followed by 3D DSA. The 3D digital subtraction angiographic images were displayed as surface shaded display images. Aneurysm detection, sac size, neck diameter, neck delineation, and relationship of aneurysm to the surrounding vessels analyzed from the two protocols were compared. Radiation dose, contrast volume, and procedural time for both examinations were also compared.
Three-dimensional DSA detected 44 aneurysms in 31 patients, with negative findings seen in four patients. A false-negative detection rate of 6.8% (three of 44) for 2D DSA was noted. There was no significant difference in aneurysm size between 3D and 2D DSA. The sizes of aneurysm necks were found to be significantly larger in 3D DSA than on 2D DSA. The aneurysm neck and relationship to surrounding vessels were significantly better demonstrated on 3D DSA than on 2D DSA. Radiation dose (entrance surface dose), contrast use, and procedural time with 3D DSA were significantly less than with 2D DSA.
Three-dimensional DSA improves the detection and delineation of intracranial aneurysms, with lower radiation dose, less contrast use, and shorter procedural time compared to 2D DSA. The size of the aneurysm neck on 3D DSA tended to be larger than on 2D DSA.
Coiling of small aneurysms can be technically challenging. These aspects of coiling tend to be less problematic in medium to large aneurysms as they are more accommodating of microcatheters and coils. When physicians are asked their opinion regarding aneurysm coilability in small aneurysms, the decision often lies in the operator's feeling that they could reasonably exclude the aneurysm with a complication rate similar to larger aneurysms. The purpose of our study was to investigate the feasibility, intraprocedural rupture rates and long term durability of endovascular coiling for small (≤4 mm) aneurysms compared with non-small (>4 mm) aneurysms. To control for factors such as vessel tortuosity and aneurysm location, a control group was chosen matched to the study group both in age and aneurysm location.
A retrospective review of 360 intracranial aneurysms coiled at our institution between 2003 and 2008 was performed. For the control group, intracranial aneurysms coiled in the same period matched to location and age were chosen.
The frequency of intraprocedural perforations was 4/34 (0.12) and 3/68 (0.04) for the small and non-small cohort, respectively (p=0.22). All patients who had a perforation in the small aneurysm groups had a good clinical outcome compared with 1/3 in the non-small group (two mortalities). The frequency of recanalization for the small and non-small groups was 3/34 (0.09) and 23/68 (0.33), respectively (p=0.006). There was no retreatments in the small aneurysm group and five (0.07) in the non-small group (p=0.116).
Coiling of small (≤4 mm) aneurysms is feasible with a reasonable complication rate. There is a non-significant increase in frequency of intraprocedural rupture with coiling of small aneurysms compared with controls matched to aneurysm location and age but this is not associated with increased morbidity. Coiling of small aneurysms leads to durable results at long term follow-up.
Procedure-related rupture during endovascular therapy of intracranial aneurysms is associated with a mortality rate of more than one third. Previously ruptured aneurysms are a known risk factor for procedure-related rupture. The objective of this study was to evaluate whether very small, ruptured aneurysms are associated with more frequent intraprocedural ruptures.
This was a retrospective cohort study in which the investigators examined consecutive ruptured aneurysms treated with coil embolization at a single institution. The study was approved by the institutional review board. Very small aneurysms were defined as < or = 3 mm. Procedure-related rupture was defined as contrast extravasation during treatment. Univariate analysis with the Fisher exact test and the Mann-Whitney U test was performed.
Between August 1992 and January 2007, 682 aneurysms were selectively treated with coils in 668 patients. Procedure-related rupture occurred in 7 (11.7%) of 60 aneurysms < or = 3 mm, compared with 14 (2.3%) of 622 aneurysms > 3 mm (relative risk 5.2, 95% confidence interval 2.2-12.8; p < 0.001). Among cases with procedure-related rupture, inflation of a compliant balloon was associated with better outcome (Glasgow Outcome Scale Score > or = 4) compared with patients treated without balloon assistance (5 of 5 compared with 7 of 16; p = 0.05). Death resulting from procedure-related rupture occurred in 8 (38%) of 21 patients, and a vegetative state occurred in 1 patient. Clinical outcome was good in the other 12 patients (57%).
Endovascular coil embolization of very small (< or = 3 mm) ruptured cerebral aneurysms is 5 times more likely to result in procedure-related rupture compared with larger aneurysms. Balloon inflation for hemostasis may be associated with better outcome in the event of intraprocedural rupture and merits further study.
The balloon remodeling technique was initially designed for the endovascular treatment of anatomically complex aneurysms, specifically wide-neck aneurysms. A nondetachable balloon is inflated in front of the aneurysm neck during coil deposition and removed at the end of the procedure. Some controversies regarding the safety of the technique were introduced by the recent publication of a series showing a much higher rate of complications with the remodeling technique compared with the standard coiling technique. However, recent data from the literature review and from the large ATENA and CLARITY series show that the safety of standard coiling and remodeling is quite similar. Anatomic results are also probably better after remodeling. Finally, due to equivalent safety and better anatomic results, the remodeling technique can be widely used in the management of both ruptured and unruptured aneurysms.
To compare the safety and efficacy of the remodeling technique with that of conventional coil embolization in a large multicenter series involving the endovascular treatment of ruptured intracranial aneurysms, the CLARITY study (Clinical and Anatomic Results in the Treatment of Ruptured Intracranial Aneurysms).
The institutional review board approved the CLARITY study, and written informed consent was obtained from all patients. A total of 768 patients (age range, 19-80 years; mean age ± standard deviation, 51.0 years ± 11.1) with 768 ruptured aneurysms were treated with either conventional coil embolization (608 patients, 79.2%) or the remodeling technique (160 patients, 20.8%). Patient and aneurysm characteristics, the rate of adverse events related to the treatment or initial intracranial hemorrhage, and patient outcome were compared between treatment groups by using the χ(2), Fisher exact, or Student t test.
The overall rate of treatment-related complications, with or without clinical manifestations, was 17.4% (106 of 608 patients) with coil embolization and 16.9% (27 of 160 patients) with remodeling (P = .999). The difference in the rates of thromboembolic events, intraoperative rupture, and early repeat bleeding between the treatment groups was not statistically significant. The cumulative morbidity and mortality rate related to the treatment in the remodeling group (3.8%, six of 160 patients) was similar to that in the coil embolization group (5.1%, 31 of 608 patients) (P = .678). Likewise, the global cumulative morbidity and mortality rates related to both the treatment and the initial hemorrhage did not differ significantly between groups (16.2% [26 of 160 patients] with remodeling and 19.6% [119 of 608 patients] with coil embolization, P = .366). The rate of adequate aneurysm occlusion, however, was significantly higher in the remodeling group (94.9%, 150 of 158 aneurysms) than in the coil embolization group (88.7%, 534 of 602 aneurysms) (P = .017).
In our large series of patients treated for ruptured aneurysms, the remodeling technique-despite being performed in aneurysms with unfavorable characteristics-was as safe as conventional coil embolization and more efficacious in terms of the rate of adequate postoperative occlusion. These results indicate that the remodeling technique can be routinely used in the treatment of ruptured aneurysms.
The aim of this study was to assess the incidence, indications, complications, and angiography results associated with balloon-assisted coil embolization (BACE) of intracranial aneurysms and to compare these factors with those for conventional coil embolization (CE).
Between 1995 and 2005, 827 intracranial aneurysms in 757 consecutive patients were packed with coils. Balloon-assisted coil embolization was used in 8.6% (71 of 827) of the coil insertion procedures and was more frequently used in large aneurysms, unruptured lesions, and those located on the vertebrobasilar system and carotid artery. Procedure-related complications leading to death or dependency were significantly higher in BACEs (14.1%) compared with those in CEs (3%). Packing densities and the results of 6-month follow-up angiography studies did not differ significantly between the two types of treatments. There was a strong trend for a higher retreatment rate in the aneurysms treated with BACE.
Balloon-assisted coil embolization of intracranial aneurysms is associated with a high complication rate and should only be used if conventional CE of these lesions is impossible or has failed and if anticipated surgical risks are too high. The BACE procedure does not improve the occlusion rates of the aneurysms on follow-up evaluation.
In some patients with nonperimesencephalic nontraumatic subarachnoid hemorrhage (aneurysmal SAH), no aneurysm can be found on digital subtraction angiography (DSA), and repeat DSA is advocated. 3D rotational angiography (3DRA) is considered superior to DSA in the detection of small intracranial aneurysms. In this study, we assessed the additional diagnostic value of 3DRA in detecting DSA-occult aneurysms in 23 patients with aneurysmal SAH.
Between January 2006 and September 2007, 298 patients with suggested ruptured intracranial aneurysm were referred for DSA, and in 98 patients, DSA was negative. Of these 98 patients, 28 had aneurysmal SAH, and in 23 of these additional 3DRA was performed in the same or in a repeat angiographic procedure.
In 18 of 23 patients (78%), a ruptured small aneurysm was diagnosed on additional 3DRA. The location of 18 aneurysms was the anterior communicating artery (n = 11), the middle cerebral artery (n = 3), the posterior communicating artery (n = 2), the ophthalmic artery (n = 1), and the posterior inferior cerebellar artery (n = 1). Aneurysm size was 3 mm in 4, 2 mm in 9, and 1 mm in 5. Of 18 aneurysms, 9 were treated with coil placement; 7 with surgical clipping; and 2 were not treated.
In this study, 18 of 23 (78%) patients with negative findings on DSA had a small ruptured aneurysm when studied with 3DRA. These were most commonly located on the anterior communicating artery.
Objective:
Precise morphologic evaluation is important for intracranial aneurysm (IA) management. Currently, clinicians manually measure IA size and neck diameter on two-dimensional digital subtraction angiography (2D-DSA) and categorize IA shape as regular/irregular on three-dimensional (3D)-DSA, which might be subject to inconsistency and bias. We investigated whether a computer-assisted 3D analytical approach could improve IA morphology assessment.
Methods:
Five neurointerventionists evaluated sizes, neck diameters, and shapes of 39 IAs using current and computer-assisted 3D approaches. In the computer-assisted 3D approach, sizes, neck diameters, and undulation index (UI, a shape irregularity metric) were extracted by semi-automated reconstruction of aneurysm geometry using 3D-DSA, followed by IA neck identification and computerized geometry assessment.
Results:
Sizes and neck diameters measured by the manual 2D approach were smaller than computer-assisted 3D measurements by 2.01mm (p<0.001) and 1.85mm (p<0.001), respectively. Applying definitions of small IAs (<7mm) and narrow-necked IAs (<4mm) from the literature, inter-rater variation in manual 2D measurements resulted in inconsistent classifications in the sizes of 14 IAs and the necks of 19 IAs. Visual inspection resulted in inconsistent shape classifications of 23 aneurysms among raters. Greater consistency was achieved by using the computer-assisted 3D approach for size (Intraclass Correlation Coefficient [ICC]:1.00), neck measurements (ICC:0.96), and shape quantification (UI, ICC:0.94).
Conclusions:
Computer-assisted 3D morphology analysis can improve accuracy and consistency in measurements compared to manual 2D measurements. It can also more reliably quantify shape irregularity using the UI. Future application of computer-assisted analysis tools could help clinicians standardize morphology evaluation, leading to more consistent IA evaluation.
Successful endovascular coiling of ruptured tiny saccular intracranial aneurysms (⩽3 mm) is technically challenging and traditionally has been associated with technical failures, as well as morbidity related to thromboembolic events and high intraoperative rupture rates. This study analyzes the feasibility, technical efficacy, and clinical outcomes of coil embolization of ruptured tiny intracranial aneurysms using current coil and microcatheter technology and techniques. We performed a retrospective review of 20 patients with 20 ruptured tiny aneurysms treated with endovascular coil embolization from 2013 to 2016 at a single high-volume academic tertiary care practice. The mean aneurysm size was 2.4 mm (median 2.5 mm, 1–3). Complete occlusion was achieved in 12 of 20 patients (60%), the remaining 7 of 20 patients (35%) had a small neck remnant, and there was 1 failure (5%) converted to microsurgical clipping. Two patients had a failed attempted surgical clip reconstruction and were subsequently coiled. There was 1 intraprocedural rupture (5%) and 1 severe parent artery vasospasm (5%) during coiling. At discharge, 60% of patients were living independently. At follow-up three patients were deceased. Mean angiographic follow-up was 139 days (SD 120). There were no aneurysm recurrences among occluded patients and there were no retreatments among those with neck remnants. Coiling of ruptured aneurysms ⩽3 mm is feasible with high occlusion rates and low complication rates. The availability of softer coils with flexible detachment zones has led to safe and effective endovascular treatment of tiny ruptured aneurysms.
The aim of this updated statement is to provide comprehensive and evidence-based recommendations for management of patients with unruptured intracranial aneurysms.
Writing group members used systematic literature reviews from January 1977 up to June 2014. They also reviewed contemporary published evidence-based guidelines, personal files, and published expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulated recommendations using standard American Heart Association criteria. The guideline underwent extensive peer review, including review by the Stroke Council Leadership and Stroke Scientific Statement Oversight Committees, before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee.
Evidence-based guidelines are presented for the care of patients presenting with unruptured intracranial aneurysms. The guidelines address presentation, natural history, epidemiology, risk factors, screening, diagnosis, imaging and outcomes from surgical and endovascular treatment.
© 2015 American Heart Association, Inc.
Endovascular treatment of small intracranial aneurysms has historically been technically challenging and has been associated with high rates of complications and intraprocedural rupture. In this study, we compared complication and recurrence rates for treatment of small aneurysms (≤4 mm) versus large aneurysms in the context of the advent of improvements in endovascular techniques and technologies.
A retrospective cohort study was performed to include all patients who underwent coiling of an intracranial aneurysm between 2005 and 2012. Small aneurysms were defined as any aneurysm 4.0 mm or smaller in all dimensions. The primary outcome was a composite outcome of the occurrence of an intraoperative rupture or a perioperative thromboembolic event. The secondary outcome of interest was aneurysm recurrence.
During the study period, 483 patients were treated using endovascular techniques; 85 (17.6%) of these patients had small aneurysms. In the small aneurysm group, there was only one (1.2%) intraoperative rupture, three (3.5%) perioperative thromboembolic events, and 11 (12.9%) incidents of aneurysm recurrence. Both the primary and secondary outcomes of interest were similar in patients presenting with small or large aneurysms. Small aneurysm size was not a risk factor for either the composite primary outcome or aneurysm recurrence in multivariate analysis.
Treatment of small intracranial aneurysms via conventional endovascular coiling techniques is not inferior to endovascular treatment of larger aneurysms based on our single institution experience. While technically challenging, such aneurysms may be treated safely and effectively with acceptable rates of complications and recurrence.
Although treatment of a ruptured aneurysm is accepted as an emergency, indication for treatment of unruptured intracranial aneurysms (IAs) is still being discussed.
Objective:
Coiling of aneurysms 3 mm in diameter or less has been associated with a relatively high rate of complications, including iatrogenic rupture. The present study aimed to determine the clinical outcome of our technique for coiling small aneurysms.
Methods:
A retrospective chart review was performed of prospectively collected data for all patients who had endovascular coiling of an aneurysm 3 mm in diameter or less between 2003 and 2008. Follow-up imaging with magnetic resonance or catheter angiography was performed at varying intervals after coiling, ranging from 1 to 6 years after the procedure. Angiographic results were assessed using the Raymond-Roy (RR) grading system. Clinical outcomes during the same period were measured using the modified Rankin Scale.
Results:
Between March 2003 and April 2008, 20 patients underwent coil embolization of an aneurysm 3 mm or smaller--17 ruptured and 3 unruptured. After the procedure, 10 aneurysms were completely occluded (RR 1), 7 had residual filling of the neck (RR 2), and 3 had residual filling of the fundus (RR 3). There were no iatrogenic ruptures. Stent assistance was used in three cases. Balloon assistance was not used. Two patients were retreated, but no aneurysm reruptured. Clinical outcomes were as expected on the basis of the presenting Hunt & Hess grade. One patient with a ruptured aneurysm died from complications related to severe vasospasm.
Conclusion:
Aneurysms 3 mm in diameter or smaller can be coiled safely with the use of both bare platinum and hydrogel-coated coils. In most cases, coiling of small aneurysms can be performed without the use of adjunctive devices such as balloons or stents.
Background:
Aneurysm size is a possible risk factor for intraoperative rupture (IOR) during coiling procedures. We aim to determine if aneurysm size 4 mm or smaller predicts IOR.
Methods:
Between January 1997 and August 2010, 689 aneurysms in 595 patients were treated by coiling at a single institution. In all, 41 were excluded from statistical analysis due to missing data leaving 648 aneurysms in 562 patients. Demographic, clinical, and procedural outcomes were collected. We compared the rate of IOR in small aneurysms (≤4 mm) with larger aneurysms (>4 mm). We also compared the rate of IOR in ruptured versus unruptured aneurysms in the above categories.
Results:
The overall rate of IOR was 4.9%. Aneurysms 4 mm or smaller were more than twice as likely to rupture on table compared to larger aneurysms (8.7% versus 3.9%; P=.022). Of note, ruptured aneurysms were more prone to IOR compared to unruptured aneurysms (7.0% versus 2.2%; P=.005). Aneurysm size 4 mm or smaller was a risk factor in small, ruptured aneurysms only (P=.019). In addition, unruptured aneurysms that were complicated by IOR were associated with higher rates of 30-day mortality (P<.001).
Conclusions:
Aneurysm size 4 mm or smaller is a risk factor for IOR in ruptured but not unruptured aneurysms. This additional risk factor should be considered when planning the management of small, ruptured aneurysms.
Objective:
To assess predictors of outcome following endovascular treatment of small ruptured intracranial aneurysms (SRA).
Methods:
Between 2004 and 2011, 91 patients with SRA (≤3 mm) were treated at our institution. Multivariate analysis was carried out to assess predictors of endovascular-related complications, aneurysm obliteration (>95%), recanalization and favorable outcome (Glasgow Outcome Scale 3-5).
Results:
Endovascular treatment was aborted in nine of 91 patients (9.9%). Procedure-related complications occurred in eight of 82 patients (9.8%) of which five were transient and three were permanent. Three patients (3.7%) undergoing endovascular treatment experienced an intraprocedural aneurysm rupture. Three of nine patients (33.3%) treated with stent- or balloon-assisted coiling experienced periprocedural complications compared with five of 73 patients (6.8%) receiving only coils or Onyx (p=0.039). There were no procedural deaths or rehemorrhages. Rates of recanalization and retreatment were 18.2% and 12.7%, respectively. No factors predicted initial occlusion or recanalization. In multivariate analysis, pretreatment factors predictive of a favorable outcome included younger age (OR 0.94; 95% CI 0.91 to 0.99, p=0.017), larger aneurysm size (OR 3.4; 95% CI 1.02 to 11.11, p=0.045), Hunt and Hess grade (OR 0.38; 95% CI 0.19 to 0.75, p=0.005) and location (OR 5.12; 95% CI 1.29 to 20.25, p=0.02). When assessing treatment and post-treatment variables, vasospasm was the only additional covariate predictive of a poor outcome (OR 5.90; 95% CI 1.34 to 25.93,p=0.019).
Conclusions:
Most patients with SRA can be treated with endovascular therapy and have limited complications. Overall predictors of outcome for patients undergoing endovascular treatment of SRA include age, aneurysm size, Hunt and Hess grade, location and post-treatment vasospasm.
The aim of this guideline is to present current and comprehensive recommendations for the diagnosis and treatment of aneurysmal subarachnoid hemorrhage (aSAH).
A formal literature search of MEDLINE (November 1, 2006, through May 1, 2010) was performed. Data were synthesized with the use of evidence tables. Writing group members met by teleconference to discuss data-derived recommendations. The American Heart Association Stroke Council's Levels of Evidence grading algorithm was used to grade each recommendation. The guideline draft was reviewed by 7 expert peer reviewers and by the members of the Stroke Council Leadership and Manuscript Oversight Committees. It is intended that this guideline be fully updated every 3 years.
Evidence-based guidelines are presented for the care of patients presenting with aSAH. The focus of the guideline was subdivided into incidence, risk factors, prevention, natural history and outcome, diagnosis, prevention of rebleeding, surgical and endovascular repair of ruptured aneurysms, systems of care, anesthetic management during repair, management of vasospasm and delayed cerebral ischemia, management of hydrocephalus, management of seizures, and management of medical complications.
aSAH is a serious medical condition in which outcome can be dramatically impacted by early, aggressive, expert care. The guidelines offer a framework for goal-directed treatment of the patient with aSAH.
The objective of this study was to analyze the place for the balloon remodeling and stenting in the endovascular treatment of intracranial aneurysms as well as the impact of their use on the failure and complications rates. Analysis was conducted in a recent 3-year period (2008-2010) in a single center.
A total of 287 aneurysms, harbored by 252 patients (age, 16-87 years; mean, 50.9 ± 13.4 years), were proposed for endovascular treatment. Patient and aneurysms characteristics, modalities of treatment (coiling, remodeling, or stenting), failure rate, and rate of adverse events related to the treatment were analyzed.
Treatment failed in 3/287 aneurysms (1.0%). The use of the remodeling technique and stenting increased over time (23.9% and 4.6% in 2008, 39.5% and 14.9% in 2009, and 43.9% and 20.7% in 2010, respectively). The remodeling technique was used in a similar percentage of cases independent of aneurysm characteristics (aneurysm status, location, and size, and neck size), except dome-to-neck ratio. Stenting was more frequently used in unruptured aneurysms, in internal carotid artery aneurysms, and in wide neck aneurysms. The rate of specific adverse events (thromboembolism and intraoperative rupture) was similar in coiling (2.8%), remodeling (6.9%), and stenting (1.1%). The rate of specific adverse events was similar in 2008, 2009, and 2010 (2.3%, 4.4%, and 6.1%, respectively).
In the endovascular management of intracranial aneurysms, the large use of the remodeling technique combined with stenting in selected cases enables a low rate of treatment failures without increasing the rate of complications.
The use of stents for treatment of morphologically unfavorable, acutely ruptured aneurysms is avoided by most operators because of concerns about the risk of using dual antiplatelet therapy in the setting of acute SAH. Our aim was to review the literature regarding stent-assisted coil embolization of acutely ruptured intracranial aneurysms to determine the safety and efficacy of this treatment option.
Articles including ≥5 patients with ruptured aneurysms who were treated acutely with stent-assisted coiling or uncovered stent placement alone were identified. Data on clinical presentation, technical success, surgical crossover, intracranial complications, and clinical outcome were evaluated.
A total of 17 articles were identified reporting 339 patients who met inclusion criteria. Among 212 patients with available data, technical success was noted in 198 (93%) patients. Three hundred twenty-six (96%) of 339 patients received both heparin during the procedure and dual-antiplatelet therapy during or immediately postprocedure. One hundred thirty (63%) of 207 aneurysms were completely occluded. Six (2%) of 339 patients required surgical crossover, usually for failure in stent placement or for intraprocedural aneurysm rupture. Clinically significant intracranial hemorrhagic complications occurred in 27 (8%) of 339 patients, including 9 (10%) of 90 patients known to have EVDs who had ventricular drain-related hemorrhages. Clinically significant thromboembolic events occurred in 16 (6%) of 288 patients. Sixty-seven percent of patients had favorable clinical outcomes, 14% had poor outcomes, and 19% died.
Stent-assisted coiling in ruptured aneurysms can be performed with high degrees of technical success, but adverse events appear more common and clinical outcomes are likely worse than those achieved without stent assistance. Thromboembolic complications appear reasonably well-controlled. Reported EVD-related hemorrhagic complications were uncommon, though the total number of EVDs placed was unknown.
Stent-assisted coiling has expanded the treatment of intracranial aneurysms, but the rates of procedure-related neurological complications and the incidence of angiographic aneurysm recurrence of this novel treatment are not yet well known. We present our experience with stent-assisted coiling with special emphasis on procedure-related neurological complications and incidence of angiographic recurrence.
Clinical and angiographic outcomes of 1137 consecutive patients (1325 aneurysms) coiled with and without stent-assisted coiling technique from January 2002 to January 2009 were retrospectively analyzed.
There were 1109 aneurysms (83.5%) treated without and 216 (16.5%) treated with stents (15 of 216; 6.9% balloon-expandable versus 201 of 216; 93.1% self-expandable stents). Stents were delivered after coiling in 55.1% (119 of 216) and before coiling in 44.9% (97 of 216) of the cases. Permanent neurological procedure-related complications occurred in 7.4% (16 of 216) of the procedures with stents versus 3.8% (42 of 1109) in the procedures without stents (logistic regression P=0.644; OR: 1.289; 95% CI: 0.439 to 3.779). Procedure-induced mortality occurred in 4.6% (10 of 216) of the procedures with stents versus 1.2% (13 of 1109) in the procedures without stents (logistic regression P=0.006; OR: 0.116; 95% CI: 0.025 to 0.531). A total of 52.7% (114 of 216) of aneurysms treated with stents have been followed so far versus 69.8% (774 of 1109) of aneurysms treated without stents, disclosing angiographic recurrence in 14.9% (17 of 114) versus 33.5% (259 of 774), respectively (Fisher exact test P<0.0001; OR: 0.3485; 95% CI: 0.2038 to 0.5960).
Stents were associated with a significant decrease of angiographic recurrences, but they were associated with more lethal complications compared with coiling without stents.
Endovascular treatment of very small aneurysms poses a significant technical challenge for endovascular therapists. The authors review their experience with a series of patients who had intracranial aneurysms smaller than 3 mm in diameter.
Between 1995 and 2006, 97 very small aneurysms (defined for purposes of this study as < 3 mm in diameter) were diagnosed in 94 patients who were subsequently referred for endovascular treatment. All patients presented after subarachnoid hemorrhage, which was attributed to the very small aneurysms in 85 patients. The authors reviewed the endovascular treatment, the clinical and angiographic results of the embolization, and the complications.
Five (5.2%) of the 97 endovascular procedures failed, and these patients underwent craniotomy and clip ligation. Of the 92 aneurysms successfully treated by coil embolization, 64 (69.6%) were completely occluded and 28 (30.4%) showed minor residual filling or neck remnants on the immediate postembolization angiogram. Complications occurred in 7 (7.2%) of 97 procedures during the treatment (3 thromboembolic events [3.1%] and 4 intraprocedural ruptures [4.1%]). Seventy-six patients were followed up angiographically; 4 (5.3%) of these 76 showed angiographic evidence of recanalization that required retreatment. The clinical outcomes for the 76 patients were also graded using the Glasgow Outcome Scale. In 61 (80.3%) cases the outcomes were graded 4 or 5, whereas in 15 (19.7%) they were graded 3. Seven patients (7.4%) died (GOS Grade 1), 2 due to procedure-related complications (intraoperative rupture) and 5 due to complications related to the presenting subarachnoid hemorrhage.
Endosaccular coil embolization of very small aneurysms is associated with relatively high rates of intraprocedural rupture, especially intraoperative rupture. With the advent of more sophisticated endovascular materials (microcatheters and microguidewires, soft and ultrasoft coils, and stents) endovascular procedures have become feasible and can lead to a good angiographic outcome.
To analyze the safety of the remodeling technique compared with the safety of the standard treatment with coils for endovascular treatment of unruptured intracranial aneurysms in a large multicenter series of patients as part of the Analysis of Treatment by Endovascular Approach of Nonruptured Aneurysms (ATENA) study.
The medical ethics committee approved the ATENA study, and all patients gave informed consent for participation in the study. The ATENA study was performed in 27 institutions. For each patient group, we recorded aneurysm characteristics, rate of adverse events related to the treatment, and patient outcome.
In this study, 547 patients (383 women, 164 men; mean age, 51.0 years +/- 11.1 [standard deviation]; range, 22-83 years) with 572 aneurysms were included; 325 patients were treated with coils alone and 222 patients were treated with the remodeling technique. The overall rate of adverse events related to the treatment-regardless of whether the adverse events led to clinical consequences-was 10.8% (35 of 325) for treatment with coils alone and 11.7% (26 of 222) for the remodeling technique. Thromboembolic events, intraoperative rupture, and device-related problems were encountered in 20 (6.2%), seven (2.2%), and eight (2.5%) of 325 patients in the standard treatment group and in 12 (5.4%), seven (3.2%), and seven (3.2%) of 222 patients in the remodeling technique group, respectively. The morbidity and mortality rates did not differ significantly between groups: 2.2% (seven of 325) and 0.9% (three of 325) in the standard treatment group and 2.3% (five of 222) and 1.4% (three of 222) in the remodeling technique group, respectively.
The remodeling technique was associated with a similar rate of adverse events and morbidity and mortality combined compared with the standard treatment with coils, and, thus, the remodeling technique is as safe as the standard treatment with coils.
Dome-to-neck ratio of intracranial aneurysms is an important predictor of outcomes of endovascular coiling. 3D imaging techniques are increasingly used in evaluating the dome-to-neck ratio of aneurysms for intervention. The purpose of this study was to determine whether 3D rotational angiography (3DRA) can be used to determine accurately the dome-to-neck ratio of intracranial aneurysms when compared with conventional 2D digital subtraction angiography (2D DSA).
A retrospective analysis of 180 patients with 205 intracranial aneurysms who underwent both 2D DSA and 3DRA for evaluation of previously untreated aneurysms was conducted. Dome-to-neck ratios were compared between 2D DSA and 3DRA images. The mean difference in dome-to-neck ratios between 2D DSA and 3DRA was calculated. The proportions of "wide-neck" aneurysms seen on 2D DSA and 3DRA were compared by using 2 different definitions of "wide-neck," including <1.5 and <2.0.
The average dome-to-neck ratio was 1.81 +/- 0.55 and 1.55 +/- 0.48 for 2D DSA and 3DRA, respectively (P < .0001). When we defined "wide-neck" as a dome-to-neck ratio <1.5, sixty-nine (33.7%) aneurysms were wide-neck on 2D DSA compared with 119 (58%) on 3DRA (P < .0001). When we defined "wide-neck" as dome-to-neck ratio <2.0, one hundred forty-two (69.3%) aneurysms were wide-neck on 2D DSA compared with 173 (84.4%) on 3DRA (P = .0004).
In this retrospective study, 3DRA measurements resulted in significantly lower dome-to-neck ratios and significantly larger proportions of aneurysms defined as "wide-neck" compared with 2D DSA. Scrutiny of 2D DSA may offer substantial benefit over 3D techniques when triaging patients to or from endovascular therapy.
To evaluate three-dimensional (3D) digital subtraction angiography (DSA) as a supplement to two-dimensional (2D) DSA in the endovascular treatment (EVT) of intracranial aneurysms.
In 22 ruptured aneurysms, neck visualization, aneurysm shape, and EVT feasibility were analyzed at 2D DSA (anteroposterior, lateral, and rotational views) and at maximum intensity projection (MIP) and surface shaded display (SSD) 3D DSA. The possibility of obtaining a working view for EVT at 3D DSA and the relevance of measurements in choosing the first coil also were assessed.
Two-dimensional DSA images clearly depicted the aneurysm neck in four of 22 aneurysms; MIP images, in 10; and SSD images, in 21, but SSD led to overestimation of the neck size in one aneurysm. Aneurysm shape was precisely demonstrated in five of 22 aneurysms at 2D DSA, in eight at MIP, and in all cases at SSD. In two of 22 aneurysms, EVT seemed to be nonfeasible at 2D DSA; however, SSD demonstrated feasibility and EVT was successfully performed. In one aneurysm, only SSD demonstrated the extension of the neck to a parent vessel, which was proved at surgery. Working views for EVT were deduced from 3D DSA findings in 20 of 21 aneurysms. The choice of the first coil was correct in 19 of 21 aneurysms.
Three-dimensional DSA is valuable for evaluating the potential for EVT, finding a working view, and performing accurate measurements.
The present retrospective study was undertaken to prove the reliability of the aspect ratio (aneurysm depth to aneurysm neck width) for predicting an aneurysmal rupture. The aspect ratio is considered a better geometric index than aneurysm size for determining the intra-aneurysmal blood flow.
We measured the aspect ratios and the sizes of aneurysms, as determined by examining angiographic films magnified 1.4x, in 129 patients with ruptured aneurysms and in 72 patients with 78 unruptured aneurysms. After categorizing the aneurysms into four groups on the basis of their locations (aneurysms of the anterior communicating artery, middle cerebral artery, internal carotid artery-posterior communicating artery [ICA-PComA], and other aneurysms), a statistical analysis of ruptured and unruptured aneurysms was performed.
The mean aneurysm size was found to be statistically significant in the aneurysms at the ICA-PComA and in locations excluding the anterior communicating artery, the middle cerebral artery, and the ICA-PComA. However, the mean aspect ratio was statistically significant at all four locations. In patients with ruptured aneurysms, no ruptured aneurysms with an aspect ratio of less than 1.0 were found. The distribution of the ruptured group versus the unruptured group with an aspect ratio of less than 1.6 at each location was 13 versus 79%, respectively, at the anterior communicating artery, 11 versus 58% at the middle cerebral artery, 11% versus 85% at the ICA-PComA, and 7 versus 81% at other locations.
The aspect ratio between ruptured aneurysms and unruptured aneurysms was found to be statistically significant, and almost 80% of the ruptured aneurysms showed an aspect ratio of more than 1.6, whereas almost 90% of the unruptured aneurysms showed an aspect ratio of less than 1.6. This study therefore suggests that the aspect ratio may be useful in predicting imminent aneurysmal ruptures.
Although digital subtraction angiography (DSA) is considered the criterion standard for depiction of intracranial aneurysms, it is often difficult to determine the relationship of overlapping vessels to aneurysms when using 2D DSA. We compared 2D and 3D DSA in evaluation of intracranial aneurysms.
Thirty-six consecutive patients with cerebral aneurysms underwent 2D and 3D DSA. After standard 2D DSA, rotational DSA was performed. Maximum intensity projection (MIP) and shaded surface display (SSD) images were created from the rotational DSA data sets. All images were assessed randomly for overall image quality, presence of aneurysm, presence of aneurysmal lobulation, visualization of aneurysmal neck, and relationship to adjacent vessels. Data analysis was conducted for 40 aneurysms treated by clip placement.
One aneurysm that was not detected at 2D DSA was classified as uncertain on the basis of rotational DSA. All aneurysms were classified as probably or definitively present on the basis of MIP and SSD findings. Overall image quality of rotational DSA, MIP, and SSD was statistically inferior to that of the standard 2D DSA for visualization of distal arteries. However, MIP and SSD images were significantly superior to those of standard 2D DSA for all other evaluations. For detection of lobulation, SSD images were significantly superior to other images, and for visualization of aneurysmal neck and relationship to neighboring arteries, SSD images were significantly superior to those of rotational DSA. For evaluation of the relationship to neighboring arteries, MIP images were significantly superior to those of rotational DSA.
Three-dimensional DSA, especially SSD, provided more detailed information for evaluating cerebral aneurysms than did standard 2D and rotational DSA.
Outcome in small aneurysms (<4 mm) treated by endovascular coiling
- C Lum
- Narayanam
- Sb
- L Silva
Stent-assisted coil embolization of intracranial aneurysms: complications in acutely ruptured versus unruptured aneurysms.
- R S Bechan
- Sprengers
- Me
- C B Majoie
Conventional endovascular treatment of small intracranial aneurysms is not associated with additional risks compared with treatment of larger aneurysms.
- W R Stetler
- T J Wilson
- Al-Holou
- Wn
Endovascular treatment of very small intracranial aneurysms: meta-analysis.
- Yamaki
- Vn
- W Brinjikji
- M H Murad
Intracranial aneurysm neck size overestimation with 3D rotational angiography: the impact on intra-aneurysmal hemodynamics simulated with computational fluid dynamics.
- J J Schneiders
- Marquering
- Ha
- L Antiga