The hypoattenuating berry sign: a reliable marker for ruptured aneurysms in subarachnoid hemorrhage patients with multiple aneurysms

BACKGROUND AND PURPOSE

Non-enhanced computed tomography (NECT) and computed tomography angiography (CTA) are useful for detecting aneurysmal subarachnoid hemorrhage (SAH) but challenging to identify ruptured aneurysms in cases of multiple aneurysms. We aimed to determine if the hypoattenuating berry sign (HBS) can identify ruptured aneurysms in SAH patients with multiple aneurysms.

METHODS

Patients who had multiple aneurysms and underwent NECT were retrospectively recruited. The HBS, blood score, size and location of aneurysm were independently analyzed. The attenuation value of HBS and surrounding SAH were recorded. The independent factors of HBS in determination of ruptured aneurysms were analyzed using multivariable logistic regression.

RESULTS

Fifty-three patients (mean age 64.2 ± 10.9 years, 83.0% female) with 112 aneurysms were enrolled. In the univariate analysis, aneurysm size, aneurysm status (ruptured), and blood score were significantly correlated with the occurrence of HBS. In the multivariate analysis, only aneurysm status showed a significant association with HBS. Aneurysms with HBS were larger than those without (6.8 ± 4.2 mm versus 4.2 ± 1.2 mm, P < 0.001), and those measured via NECT were larger than those measured via DSA (7.2 ± 3.8 mm vs. 6.8 ± 4.2 mm, P < 0.001). HBS was found in 51.8% of all aneurysms and in 87.7% of ruptured aneurysms on NECT. Raters had high agreement on aneurysm size (ICC = 0.829), HBS presence (kappa = 0.928), and blood score (kappa = 0.780).

CONCLUSIONS

The HBS can be used to detect ruptured aneurysm in patient with SAH and multiple aneurysms.

Accuracy of radiomics-Based models in distinguishing between ruptured and unruptured intracranial aneurysms: A systematic review and meta-Analysis

INTRODUCTION

Intracranial aneurysms (IAs) pose a severe health risk due to the potential for subarachnoid hemorrhage upon rupture. This study aims to conduct a systematic review and meta-analysis on the accuracy of radiomics features derived from computed tomography angiography (CTA) in differentiating ruptured from unruptured IAs.

MATERIALS AND METHODS

A systematic search was performed across multiple databases for articles published up to January 2024. Observational studies analyzing CTA using radiomics features were included. The area under the curve (AUC) for classifying ruptured vs. unruptured IAs was pooled using a random-effects model. Subgroup analyses were conducted based on the use of radiomics-only features versus radiomics plus additional image-based features, as well as the type of filters used for image processing.

RESULTS

Six studies with 4,408 patients were included. The overall pooled AUC for radiomics features in differentiating ruptured from unruptured IAs was 0.86 (95% CI: 0.84-0.88). The AUC was 0.85 (95% CI: 0.82-0.88) for studies using only radiomics features and 0.87 (95% CI: 0.83-0.91) for studies incorporating radiomics plus additional image-based features. Subgroup analysis based on filter type showed an AUC of 0.87 (95% CI: 0.83-0.90) for original filters and 0.86 (95% CI: 0.81-0.90) for studies using additional filters.

CONCLUSION

Radiomics-based models demonstrate very good diagnostic accuracy in classifying ruptured and unruptured IAs, with AUC values exceeding 0.8. This highlights the potential of radiomics as a useful tool in the non-invasive assessment of aneurysm rupture risk, particularly in the management of patients with multiple aneurysms.

The clinical challenge of subarachnoid hemorrhage associated with multiple aneurysms when the bleeding source is not certainly identifiable

BACKGROUND

Multiple intracranial aneurysms (IAs) are encountered in 20-30% of the subarachnoid hemorrhages (SAH). Neuroimaging and clinical examination are usually sufficient to detect the bleeding source, but sometimes it can be misdiagnosed with catastrophic consequences.

METHODS

We reviewed our diagnostic work-up for all patients admitted from January 2016 to December 2020 for SAH with multiple IAs accounting for our rate of diagnostic failure. Then, we grouped the patients into 4 categories according to aneurysms topography and described our operative protocol in case of uncertain bleeding origin.

RESULTS

Sixty-two patients harboring 161 IAs were included. The bleeding source was identified in 56 patients (90.3%), who harbored other 81 bystander aneurysms. In 6 cases (9.7%) with a total of 24 aneurysms we failed the bleeding source identification. According to IAs topography, we grouped the IAs multiplicity in: 1) anterior plus posterior circulation IAs; 2) multiple posterior circulation IAs; 3) bilateral anterior circulation IAs; and 4) multiple ipsilateral anterior circulation IAs. In case of unidentified bleeding source, key-elements favoring the simultaneous multiple IAs treatment were their number, morphology, topography, clinicians' experience, and management modality as endovascular treatment allows a faster exclusion of multiple IAs distant one each other compared with surgery. MCA involvement represented the more frequent reason to prefer multiple clipping rather than multiple coiling.

CONCLUSIONS

In a small percentage of patients with SAH with multiple IAs, bleeding source identification can be difficult. Until the routinely availability of new tools such as vessel wall imaging or computational fluid dynamics, an experienced neurovascular team and strategies aiming to simultaneously exclude multiple IAs remain mandatory.

Two consecutive ruptured intracranial aneurysm in patient with multiple intracranial aneurysms

When aneurysmal subarachnoid hemorrhage due to multiple aneurysms is suspected, identifying the rupture site is essential to determine the exact surgical site, but it may not be easy. Even if embolization is adequately performed, complications may remain. Typical complications include rebleeding and hydrocephalus in the early phase and delayed cerebral ischemia in the delayed phase. Herein, we describe a case of rupture of an intracranial aneurysm after performing embolization for a different ruptured intracranial aneurysm in a patient with multiple intracranial aneurysms. Patients with multiple intracranial aneurysms need to be considered for closer observation than those with a single ruptured intracranial aneurysm, even if the patient's prognosis is good.

Application of zone classification in multiple intracranial aneurysmal subarachnoid hemorrhage treatment strategies

Background

The options of surgical approach and treatment stage are two challenging treatment strategy issues with multiple intracranial aneurysmal subarachnoid hemorrhage (MIA-SAH).

Methods

We retrospectively analyzed data from patients with MIA-SAH who underwent surgery in our center between January 1, 2014 and September 1, 2022. To define "zone classification", the cranial cavity was divided into four zones by the planes of cerebral falx and tentorium cerebelli. Aneurysms isolated to one zone were defined as zone classification I; those crossing two zones were defined as zone classification II; those crossing three zones were defined as zone classification III; and those crossing four zones were defined as zone classification IV. General and aneurysmal-related characteristics of patients with different zone classifications were collected and compared between two surgical approaches. Multivariate logistic regression analysis was used to identify factors independently associated with multistage treatment options.

Results

A total of 226 patients with 523 aneurysms were included. The proportion of patients undergoing endovascular treatment increased with higher zone classification (I: 85.4%; II: 94.0%; III: 100.0%; IV: 100.0%). The proportion of patients receiving one-stage treatment decreased with higher zone classification (I: 60.2%; II: 33.6%; III: 0.0%; IV: 0.0%). Compared with patients undergoing microsurgical clipping, more patients undergoing endovascular treatment had zone classification II-IV (56.9% vs. 31.8%, p = 0.025). Zone classification II-IV (odds ratio [OR] = 3.821, 95% confidence interval [CI]: 2.041-7.154, p < 0.001), endovascular treatment (OR = 8.756, 95% CI: 2.589-29.609, p < 0.001), and size of all unruptured aneurysms <3 mm (OR = 4.531, 95% CI: 2.315-8.871, p < 0.001) were each independently associated with multistage treatment.

Conclusions

Zone classification provides a new idea in MIA-SAH treatment strategies, especially regarding surgical approach and treatment stage options.

Evaluation of unruptured aneurysm scoring systems and ratios in subarachnoid hemorrhage patients with multiple intracranial aneurysms

Background

This study aims to appraise aneurysm scores and ratios' ability to discriminate between ruptured aneurysms and unruptured intracranial aneurysms (UIAs) in subarachnoid hemorrhage (SAH) patients harboring multiple intracranial aneurysms (MICAs). We, then, investigate the most frequent risk factors associated with MICAs.

Methods

We retrospectively applied unruptured intracranial aneurysm treatment score (UIATS) and population hypertension age size of aneurysm earlier SAH from another aneurysm site of aneurysm (PHASES) score, aspect, and dome-to-neck ratio to the 59 consecutive spontaneous SAH patients with MICAs admitted between January 2000 and December 2015 to the Department of Neurosurgery of the University Hospital Center "Hôpital des Spécialités" of Rabat (Morocco). Patients with at least two intracranial aneurysms (IAs) confirmed on angiography were included in the study.

Results

Fifty-nine patients were harboring 128 IAs. The most frequent patient-level risk factors were arterial hypertension (AHT) 30.5 % (n = 18) and smoking status 22.0 % (n = 13). A PHASES score recommended treatment in 52 of 60 ruptured aneurysms and in six of 68 UIAs with a sensitivity of 31.67% and a specificity of 76.47%. UIATS recommended treatment in 26 of 62 ruptured aneurysms and in 35 of 55 UIAs with a sensitivity of 41.9% and a specificity of 63.6%. Aspect ratio recommended treatment in 60 of 60 ruptured aneurysms and in 63 of 68 UIAs with a sensitivity of 100% and a specificity of 88.24%. Dome-to-neck ratio recommended treatment in 45 of 60 ruptured aneurysms and in 48 of 68 UIAs with a sensitivity of 80% and a specificity of 63.24%. The aspect ratio (area under the curve [AUC] = 0.953) AUC > 0.8 has a higher discriminatory power between ruptured aneurysms and UIAs.

Conclusion

AHT and smoking status were the most common risk factors for intracranial multiple aneurysms and the aspect ratio and PHASES score were the most powerful discrimination tools between ruptured aneurysms and the UIAs.

Endovascular treatment of multiple intracranial aneurysms in patients with subarachnoid hemorrhage: one or multiple sessions?

Objective

This study aimed to compare the safety and efficacy of single- and multiple-stage endovascular treatment in aneurysmal subarachnoid hemorrhage (SAH) patients with multiple intracranial aneurysms.

Methods

We retrospectively analyzed the clinical and imaging data of 61 patients who harbored multiple aneurysms and presented to our institution with aneurysmal subarachnoid hemorrhage. Patients were grouped according to endovascular treatment strategy: one-stage or multiple-stage.

Result

The 61 study patients harbored 136 aneurysms. One aneurysm in each patient had ruptured. In the one-stage treatment group, all 66 aneurysms in 31 patients were treated in one session. The mean follow-up was 25.8 months (range, 12-47). At the last follow-up, the modified Rankin scale was ≤2 in 27 patients. In total, 10 complications occurred (cerebral vasospasm, six patients; cerebral hemorrhage, two patients; and thromboembolism, two patients). In the multiple-stage treatment group, only the ruptured aneurysm (30 in total) was treated at the time of presentation, and the remaining aneurysms (40 in total) were treated later. The mean follow-up was 26.3 months (range, 7-49). At the last follow-up, the modified Rankin scale score was ≤2 in 28 patients. In total, five complications occurred (cerebral vasospasm, four patients; and subarachnoid hemorrhage, one patient). During the follow-up period, there was one recurrence of aneurysm with subarachnoid hemorrhage in the single-stage treatment group and four recurrences in the multiple-stage treatment group.

Conclusion

Both single- and multiple-stage endovascular treatment is safe and effective in aneurysmal subarachnoid hemorrhage patients who harbor multiple aneurysms. However, multiple-stage treatment is associated with a lower rate of hemorrhagic and ischemic complications.

Acute Subdural Hematoma Associated with Aneurysmal Rupture: A Case Series and Review of Literature

BACKGROUND

Ruptured cerebral aneurysms represent a neurosurgical emergency with characteristic clinical presentation and imaging findings. However, atypical presentations may occur in association with acute subdural hematomas (SDHs).

METHODS

A retrospective review was conducted at our institution between 2013 and 2021 to identify patients with aneurysmal rupture presenting with SDH. Cases were reviewed for clinical presentation, imaging findings, management, and outcome.

RESULTS

A total of 8 patients were included in this review with an average age of 48.5 years. Six patients were women. The average Glasgow coma scale upon arrival was 6.3, and the Hunt-Hess average grade was 4.6. Aneurysm locations included posterior communicating artery (n = 3), anterior communicating artery (n = 2), middle cerebral artery (n = 2), and internal carotid artery terminus (n = 1). The size of aneurysm varied between 3 and 11 mm. Seven patients required surgical intervention, either craniotomy or craniectomy for hematoma evacuation, and aneurysms were treated by coiling (n = 2) or clipping (n = 6).

CONCLUSIONS

Ruptured aneurysms may present with SDH with or without significant subarachnoid hemorrhage. This illustrative case series highlights this challenging presentation and the importance of early recognition and appropriate management.

Identification of ruptured intracranial aneurysms using the aneurysm-specific prediction score in patients with multiple aneurysms with subarachnoid hemorrhages- a Chinese population based external validation study

Background

For patients with aneurysmal subarachnoid hemorrhages (SAHs) and multiple intracranial aneurysms (MIAs), a simple and fast imaging method that can identify ruptured intracranial aneurysms (RIAs) may have great clinical value. We sought to use the aneurysm-specific prediction score to identify RIAs in patients with MIAs and evaluate the aneurysm-specific prediction score.

Methods

Between May 2018 and May 2021, 134 patients with 290 MIAs were retrospectively analyzed. All patients had an SAH due to IA rupture. CT angiography (CTA) was used to assess the maximum diameter, shape, and location of IAs to calculate the aneurysm-specific prediction score. Then, the aneurysm-specific prediction score was applied to RIAs in patients with MIAs.

Results

The IAs with the highest aneurysm-specific prediction scores had not ruptured in 17 (12.7%) of the 134 patients with 290 MIAs. The sensitivity, specificity, false omission rate, diagnostic error rate, and diagnostic accuracy of the aneurysm-specific prediction score were higher than those of the maximum diameter, shape, and location of IAs.

Conclusions

The present study suggests that the aneurysm-specific prediction score has high diagnostic accuracy in identifying RIAs in patients with MIAs and SAH, but that it needs further evaluation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02727-w.

Multiplanar CT evaluation of aneurysm rupture signs in subarachnoid hemorrhage

PURPOSE

In subarachnoid hemorrhage, noncontrast CT features are used to guide the localization of ruptured aneurysms on CT angiography and DSA. Multiplanar CT may improve the localization of aneurysm rupture sites over axial plane CT alone.

METHODS

Multiplanar CT in three orthogonal planes was used to evaluate 94 cases of SAH. Two investigators independently evaluated each imaging plane for focal thick SAH with mass effect, intracerebral hemorrhage, focal edema, filling defect, subdural hemorrhage, and dominant intraventricular hemorrhage. Also, rupture site was qualitatively identified by combining these variables in each plane and combination of three planes. DSA served as the gold standard to locate the rupture sites.

RESULTS

Interobserver agreement was k 0.60 to 0.79 for axial, k 0.43 to 0.86 for coronal and k 0.43 to 0.74 for sagittal planes. Good to substantial agreement was observed for the localization of rupture site in three planes (focal SAH with mass effect - k 0.78 to 0.85; filling defect - k 0.95 to 1.0; intracerebral hemorrhage - k 1.0; focal edema k 1.0; subdural hemorrhage - k 0.61 to 0.83). Dominant intraventricular hemorrhage revealed significant association with DSA to locate ruptured aneurysms (Fisher's exact test - Pr <  = P (< 0.001)). With non-missing data, frequency of correct ratings to locate rupture site was 66/67 (99%) in axial plane, 59/66 (89%) in coronal plane, 64/67 (96%) in sagittal plane and 77/77 (100%) in combined 3 planes.

CONCLUSIONS

Multiplanar CT head is more successful than axial plane CT alone for the localization of aneurysm rupture sites in SAH.

Kissing Aneurysms: Radiological and Surgical Difficulties in 30 Operated Cases and a Proposed Classification

OBJECTIVE

The first aim of this study is to bring up the radiological and surgical difficulties of kissing aneurysms and to present solutions. The second aim is to develop a classification that can help to predict the difficulties encountered during surgery.

METHODS

The records of 817 patients who were operated on for aneurysm were reviewed retrospectively to identify kissing aneurysms. The radiological and clinical databases of these patients were evaluated in detail.

RESULTS

Kissing aneurysms were detected in 30 patients (3.6%). Radiologically correct diagnosis rate of kissing aneurysms was 80% throughout the series. The most common locations were the anterior communicating artery (12 cases, 40%) and the middle cerebral artery (12 cases, 40.0%). The ruptured aneurysm could not be detected preoperatively in 24% of the patients. Intraoperative rupture occurred in 4 patients (13.3%). Accompanying vascular anomaly/variation was seen in 16 patients (53.3%). As detailed in the text, kissing aneurysms were divided into 3 types according to their position with each other on the parent artery from the surgeon's point of view during surgery: type I (proximal/distal), type II (superior/inferior), and type III (right/left).

CONCLUSIONS

Despite advanced angiographic techniques, even today, kissing aneurysms can be misinterpreted as a single bilobular aneurysm. The ruptured aneurysm may not be detectable preoperatively. These complex aneurysms have a high intraoperative rupture risk. Accompanying vascular anomalies are more common than expected. Clip selection and sequencing are important. Proposed classification helps the surgeon to be aware of intraoperative difficulties that he/she may encounter in advance.

Morphology-based radiomics signature: a novel determinant to identify multiple intracranial aneurysms rupture

We aimed to develop and validate a morphology-based radiomics signature nomogram for assessing the risk of intracranial aneurysm (IA) rupture. A total of 254 aneurysms in 105 patients with subarachnoid hemorrhage and multiple intracranial aneurysms from three centers were retrospectively reviewed and randomly divided into the derivation and validation cohorts. Radiomics morphological features were automatically extracted from digital subtraction angiography and selected by the least absolute shrinkage and selection operator algorithm to develop a radiomics signature. A radiomics signature-based nomogram was developed by incorporating the signature and traditional morphological features. The performance of calibration, discrimination, and clinical usefulness of the nomogram was assessed. Ten radiomics morphological features were selected to build the radiomics signature model, which showed better discrimination with an area under the curve (AUC) equal to 0.814 and 0.835 in the derivation and validation cohorts compared with 0.747 and 0.666 in the traditional model, which only include traditional morphological features. When radiomics signature and traditional morphological features were combined, the AUC increased to 0.842 and 0.849 in the derivation and validation cohorts, thus showing better performance in assessing aneurysm rupture risk. This novel model could be useful for decision-making and risk stratification for patients with IAs.

Clinical Characteristics of Ruptured Intracranial Aneurysm in Patients with Multiple Intracranial Aneurysms

OBJECTIVE

It is difficult to correctly identify the ruptured aneurysm in patients with multiple intracranial aneurysms. Here, we investigated the clinical characteristics of ruptured intracranial aneurysms in such patients.

METHODS

We retrospectively analyzed 361 patients who underwent microsurgical clipping of ruptured intracranial aneurysms at our institution from 2012 to 2018. Patients' age, sex, Fisher group, World Federation of Neurosurgical Societies grade, size (neck width, depth, maximum diameter), location, and shape of intracranial aneurysm, and hemorrhage pattern on admission were reviewed.

RESULTS

In total, 266 patients (74%) had single intracranial aneurysms and 95 (26%) had multiple intracranial aneurysms. Eighty-nine of the 95 multiple intracranial aneurysms (94%) had irregular shape (P < 0.01). The median aspect ratios of ruptured and unruptured intracranial aneurysms were 2.2 ± 1.1 and 1.0 ± 0.4, respectively (P < 0.01). Twelve of 95 patients (13%) had ruptured intracranial aneurysms that were smaller than unruptured intracranial aneurysms. Among the 12 patients, the aspect ratios of ruptured intracranial aneurysms were greater than those of unruptured intracranial aneurysms (P < 0.01). Regarding morphologic characteristics, aspect ratio, maximum size, and irregular shape could be the useful predictive factors, but the greatest aspect ratio among patients with multiple aneurysms was the most predictive of an intracranial aneurysm rupture, after adjustment for aneurysmal size (adjusted odds ratio 217.82; 95% confidence interval 56.41-841.08).

CONCLUSIONS

The results of this study indicate that the aspect ratio is the most predictive factor of a ruptured intracranial aneurysm in patients with multiple intracranial aneurysms.

A predictive score for identification of rupture site in subarachnoid haemorrhage with multiple intracranial aneurysm

PURPOSE

The rigid method of identifying the rupture site in cases of subarachnoid haemorrhage (SAH) with multiple intracranial aneurysms (MIAs) is still unclear. Here we present a reliable method by using a combination of six predictors.

MATERIALS AND METHODS

Concerning the 48 SAH patients with MIAs who visited the Showa General Hospital during the period from January 2005 to March 2016, several predictors of rupture site such as the aneurysm-related morphologic features (size, aspect ratio, shape, bleb), aneurysm location, and the distribution of SAH were investigated. Compared with other coexisting aneurysms in each predictor, each aneurysm was categorized into 'suspicion' or 'non-suspicion', and we analyzed the association between 'suspicion' and rupture.

RESULTS

In the first analysis, all variables were associated with rupture and included in the multivariate logistic regression analysis. The presence of bleb (OR, 20.7; CI, 2.3-186; p = .007) and the aneurysm location (OR, 23.5; CI, 5.2-106; p < .001) were significantly associated with rupture in multivariate logistic regression analysis. Based on the results, a predictive score for rupture was created and calculated for each aneurysm, and the aneurysm with highest predictive score in each patient was categorized into 'suspicion'. 'Suspicion' in the predictive score was significantly associated with rupture (OR, 412.5; CI, 52.2-16384; p < .001). The sensitivity (0.90), specificity (0.98) and the accuracy (0.94) of identifying the rupture site by the predictive score were quite satisfactory.

CONCLUSION

Our results suggest that the predictive score may be an excellent parameter to identify the rupture site in cases of SAH with MIAs.

Fusion of subarachnoid hemorrhage data and computed tomography angiography data is helpful to identify the rupture source in patients with multiple intracranial aneurysms

Determining the rupture source is imperative in patient with aneurysmal subarachnoid hemorrhage (SAH). About one third of SAH cases with multiple intracranial aneurysms cannot be certain of the rupture source according to the hemorrhage pattern. This study aims to identify of the rupture source in patients with multiple intracranial aneurysms by fusing SAH data and computed tomography angiography (CTA) data. This retrospective study included 52 aneurysmal SAH patients with multiple intracranial aneurysms. In the 52 patients, 36 had definitive hemorrhage patterns on computed tomography imaging. And the other 16 patients had non-definitive hemorrhage patterns, which were bewildered for us to determine the ruptured aneurysms. Fusion of SAH data and CTA data was performed to demonstrate the spatial relationship between the SAH with each aneurysm by using the 3D Slicer software. For the patients with definitive bleed patterns, all of the suspected ruptured aneurysms were confirmed to be accurate according to the surgical records. Interestingly, the suspected rupture sources were correct in 14 of 16 patients with non-definitive hemorrhage patterns. For all 52 patients with multiple intracranial aneurysms, the ruptured aneurysms were identified in 50 cases (96.2%). In conclusion, fusion of SAH data and CTA data can precisely demonstrate the spatial relationship between the SAH with each aneurysm, which is helpful to determine the ruptured aneurysm in patients with multiple intracranial aneurysms.

Single-stage clipping with bifrontal and bilateral frontotemporal craniotomies for subarachnoid hemorrhage with multiple cerebral aneurysms using Sugita head holding system: A case report

Background:

Subarachnoid hemorrhage with multiple aneurysms is very challenging because it is difficult to identify the ruptured aneurysm. We could not identify the ruptured aneurysm preoperatively, so we decided to treat all of the aneurysms as a single-stage surgery.

Case Description:

A 79-year-old woman was diagnosed with subarachnoid hemorrhage with multiple cerebral aneurysms at the right distal anterior cerebral artery, left middle cerebral artery, and right internal carotid artery- posterior communicating artery bifurcation. We could not identify the ruptured aneurysm preoperatively. We fixed her head using the Sugita head holding system (Mizuho Co., Ltd., Tokyo) and performed clipping for each aneurysm with bifrontal craniotomy and bilateral frontotemporal craniotomy as a single-stage operation. The last aneurysm seemed ruptured, and clipping for all the aneurysms was successful. She was discharged with a good postoperative course. The Sugita head holding system allowed turning the head of the patient toward the right and left with single fixation, leading to this single-stage operation.

Conclusion:

Several methods for identifying a ruptured aneurysm from multiple aneurysms have been reported, but under limited medical resources, this procedure would be one of the treatment strategies.

Multiple aneurysms in subarachnoid hemorrhage - identification of the ruptured aneurysm, when the bleeding pattern is not self-explanatory - development of a novel prediction score

BACKGROUND

In aneurysmal subarachnoid hemorrhage (SAH) and multiple intracranial aneurysms (MIAs) identification of the bleeding source cannot always be assessed according to the hemorrhage pattern. Therefore, we developed a statistical model for the prediction of the ruptured aneurysm in patients with SAH and multiple potential bleeding sources at the time of ictus.

METHODS

Between 2012 and 2015, 252 patients harboring 619 aneurysms were admitted to the authors' institution. Patients were followed prospectively. Aneurysm and patient characteristics, as well as radiological findings were entered into a computerized database. Gradient boosting techniques were used to derive the statistical model for the prediction of the ruptured aneurysm. Based on the statistical prediction model, a scoring system was produced for the use in the clinical setting. The aneurysm with the highest score poses the highest possibility of being the bleeding source. The prediction score was then prospectively applied to 34 patients suffering from SAH and harboring MIAs.

RESULTS

According to the statistical prediction model the main factors affecting the rupture in patients harboring multiple aneurysms were: 1) aneurysm size, 2) aneurysm location and 3) aneurysm shape. The prediction score identified correctly the ruptured aneurysm in all the patients that were used in the prospective validation. Even in the five most debatable and challenging cases assessed in the period of prospective validation, for which the score was designed for, the ruptured aneurysm was predicted correctly.

CONCLUSIONS

This new and simple prediction score might provide additional support for neurovascular teams for treatment decision in SAH patients harboring multiple aneurysms. In a small prospective sample, the prediction score performed with high accuracy but larger cohorts for external validation are warranted.

Novel Models for Identification of the Ruptured Aneurysm in Patients with Subarachnoid Hemorrhage with Multiple Aneurysms

BACKGROUND AND PURPOSE

In patients with SAH with multiple intracranial aneurysms, often the hemorrhage pattern does not indicate the rupture source. Angiographic findings (intracranial aneurysm size and shape) could help but may not be reliable. Our purpose was to test whether existing parameters could identify the ruptured intracranial aneurysm in patients with multiple intracranial aneurysms and whether composite predictive models could improve the identification.

MATERIALS AND METHODS

We retrospectively collected angiographic and medical records of 93 patients with SAH with at least 2 intracranial aneurysms (total of 206 saccular intracranial aneurysms, 93 ruptured), in which the ruptured intracranial aneurysm was confirmed through surgery or definitive hemorrhage patterns. We calculated 13 morphologic and 10 hemodynamic parameters along with location and type (sidewall/bifurcation) and tested their ability to identify rupture in the 93 patients. To build predictive models, we randomly assigned 70 patients to training and 23 to holdout testing cohorts. Using a linear regression model with a customized cost function and 10-fold cross-validation, we trained 2 rupture identification models: RIM_C using all parameters and RIM_M excluding hemodynamics.

RESULTS

The 25 study parameters had vastly different positive predictive values (31%-87%) for identifying rupture, the highest being size ratio at 87%. RIM_C incorporated size ratio, undulation index, relative residence time, and type; RIM_M had only size ratio, undulation index, and type. During cross-validation, positive predictive values for size ratio, RIM_M, and RIM_C were 86% ± 4%, 90% ± 4%, and 93% ± 4%, respectively. In testing, size ratio and RIM_M had positive predictive values of 85%, while RIM_C had 92%.

CONCLUSIONS

Size ratio was the best individual factor for identifying the ruptured aneurysm; however, RIM_C, followed by RIM_M, outperformed existing parameters.