Diagnosis Of Unruptured Intracranial Aneurysms Research Articles

Complex networks approach to study comorbidities in patients with unruptured intracranial aneurysms

The role of complex network analysis in patients with diagnosis of unruptured intracranial aneurysm is unexplored. The objective of this study is to assess the applicability of this methodology in aneurysm patients. We retrospectively analyze comprehensive unbiased local digital data of a large number of patients treated for any reason between January 2004 and July 2019. We apply an age-cohort approach to a total of 628,831 patients and construct the diagnostic history of each patient—and include the information how old the patient was when diagnosed for the first time with each diagnosis coded according to International Classification of Diseases. For each cohort of age within a 10 year interval and for each gender, we construct a statistically validated comorbidity network and focused on crucial comorbidity links that the aneurysm code has to other disease codes within the whole network. For all cohorts of different age and gender, the analysis shows that 267 diagnose codes have nearest neighbour statistically validated links to unruptured aneurysm ICD code. Among the 267 comorbidities, 204 (76%) were found in patients aged from 40 to 69-years old. Patterns of connectivity with aneurysms were found for smoking, hypertension, chronic obstructive pulmonary disease, dyslipidemia, and mood disorders. A few uncommon connections are also detected in cohorts of female patients. Our study explored the applicability of network analysis and statistical validation in aneurysm observational study.

Risk of Cerebral Aneurysm Rupture After Liver Transplantation: Development and Validation of a Hemorrhagic Stroke Scoring Model.

Liver transplantation (LT) patients appear to be more prone to neurological events compared to individuals undergoing other types of solid-organ transplantation. The aims of the present study were to analyze the prevalence of unruptured intracranial aneurysms (UIAs) in patients undergoing liver transplantation (LT) and to examine the perioperative occurrence of subarachnoid hemorrhage (SAH). Also, it intended to systematically identify the risk factors of SAH and hemorrhagic stroke (HS) within a year after LT and to develop a scoring system which involves distinct clinical features of LT patients. Patients who underwent LT from January 2012 to March 2022 were analyzed. All included patients underwent neurovascular imaging within 6 months before LT. We conducted an analysis of prevalence and radiological features of UIA and SAH. The clinical factors that may have an impact on HS within one year of LT were also reviewed. Total of 3,487 patients were enrolled in our study after applying inclusion and exclusion criteria. The prevalence of UIA was 5.4%. The incidence of SAH and HS within one year following LT was 0.5% and 1.6%, respectively. We developed a scoring system based on multivariable analysis to predict the HS within 1-year after LT. The variables were a poor admission mental status, the diagnosis of UIA, serum ammonia levels, and Model for End-stage Liver Disease (MELD) scores. Our model showed good discrimination among the development (C index, 0.727; 95% confidence interval [CI], 0.635-0.820) and validation (C index, 0.719; 95% CI, 0.598-0.801) cohorts. The incidence of UIA and SAH was very low in LT patients. A poor admission mental status, diagnosis of UIA, serum ammonia levels, and MELD scores were significantly associated with the risk of HS within one year after LT. Our scoring system showed a good discrimination to predict the HS in LT patients.

Diagnosis of Unruptured Intracranial Aneurysms Using Proton-Density Magnetic Resonance Angiography: A Comparison With High-Resolution Time-of-Flight Magnetic Resonance Angiography.

Differentiating intracranial aneurysms from normal variants using CT angiography (CTA) or MR angiography (MRA) poses significant challenges. This study aimed to evaluate the efficacy of proton-density MRA (PD-MRA) compared to high-resolution time-of-flight MRA (HR-MRA) in diagnosing aneurysms among patients with indeterminate findings on conventional CTA or MRA. In this retrospective analysis, we included patients who underwent both PD-MRA and HR-MRA from August 2020 to July 2022 to assess lesions deemed indeterminate on prior conventional CTA or MRA examinations. Three experienced neuroradiologists independently reviewed the lesions using HR-MRA and PD-MRA with reconstructed voxel sizes of 0.253 mm3 or 0.23 mm3, respectively. A neurointerventionist established the gold standard with digital subtraction angiography. We compared the performance of HR-MRA, PD-MRA (0.253-mm3 voxel), and PD-MRA (0.23-mm3 voxel) in diagnosing aneurysms, both per lesion and per patient. The Fleiss kappa statistic was used to calculate inter-reader agreement. The study involved 109 patients (average age 57.4 ± 11.0 years; male:female ratio, 11:98) with 141 indeterminate lesions. Of these, 78 lesions (55.3%) in 69 patients were confirmed as aneurysms by the reference standard. PD-MRA (0.253-mm3 voxel) exhibited significantly higher per-lesion diagnostic performance compared to HR-MRA across all three readers: sensitivity ranged from 87.2%-91.0% versus 66.7%-70.5%; specificity from 93.7%-96.8% versus 58.7%-68.3%; and accuracy from 90.8%-92.9% versus 63.8%-69.5% (P ≤ 0.003). Furthermore, PD-MRA (0.253-mm3 voxel) demonstrated significantly superior per-patient specificity and accuracy compared to HR-MRA across all evaluators (P ≤ 0.013). The diagnostic accuracy of PD-MRA (0.23-mm3 voxel) surpassed that of HR-MRA and was comparable to PD-MRA (0.253-mm3 voxel). The kappa values for inter-reader agreements were significantly higher in PD-MRA (0.820-0.938) than in HR-MRA (0.447-0.510). PD-MRA outperformed HR-MRA in diagnostic accuracy and demonstrated almost perfect inter-reader consistency in identifying intracranial aneurysms among patients with lesions initially indeterminate on CTA or MRA.

An Analysis of the Incidence and Cost of Intracranial Aneurysm and Subarachnoid Haemorrhage Treatment between 2013 and 2021

The incidence of unruptured intracranial aneurysms (UIAs) amounts to 3.2% among adults. The annual risk of aneurysm rupture is 2-10% and it results in subarachnoid haemorrhage (SAH). The aim of this study is to assess changes in the incidence of unruptured intracranial aneurysms and subarachnoid haemorrhages in Poland between 2013 and 2021 and the cost associated with their in-hospital treatment in the acute phase. The analysis was based on the National Health Fund database. Patients diagnosed with UIA and SAH and hospitalised between 2013 and 2021 were chosen. The statistical analysis was performed with an assumed significance level of α = 0.05. The ratio between the prevalence of SAH and UIA diagnoses was 4:6. The proportion of women in relation to men was higher in both diagnoses. The highest proportions of patients with diagnoses SAH and UIA were found in highly urbanised provinces. The value of medical services in 2021 compared to 2013 increased by 81.8%. The highest values in this period were recorded in Mazowieckie province, and the lowest were recorded in Opolskie province. The overall number of patients hospitalised with diagnosis of UIA or SAH did not decrease, but the risk of aneurysm rupture probably decreased, which resulted in lower incidence of SAH in subsequent years of observation. The recorded changes in the dynamics of the value of medical services per patient or per hospitalisation largely coincided. However, it is difficult to speculate on expected value levels as not all provinces showed linear changes in the value of services provided.

Diagnosis of Unruptured Intracranial Aneurysm by High-Performance Serum Metabolic Fingerprints.

Unruptured intracranial aneurysm (UIA) is a high-risk cerebrovascular saccular dilatation, the effective medical management of which depends on high-performance diagnosis. However, most UIAs are diagnosed incidentally during neurovascular imaging modalities, which are time-consuming and harmful (e.g., radiation). Serum metabolic fingerprints is a promising alternative for early diagnosis of UIA. Here, nanoparticle enhanced laser desorption/ionization mass spectrometry is applied to obtain high-performance UIA-specific serum metabolic fingerprints. Diagnostic performance with an area-under-the-curve (AUC) of 0.842 (95% confidence interval (CI): 0.783-0.891) is achieved by the constructed machine learning (ML) model, including ML algorithm selection and feature selection. Lactate, glutamine, homoarginine, and 3-methylglutaconic acid are identified as the metabolic biomarker panel, which showed satisfactory diagnosis (AUC of 0.812, 95% CI: 0.727-0.897) and effective growth risk assessment (p<0.05, two-tailed t-test) of UIAs. This work aims to promote the diagnostics of UIAs and metabolic biomarker screening for medical management.

Safety and Effectiveness of the Novel Catheter 3.0 System for Diagnostic Cerebral Angiography: A Pilot Study.

The purpose of this study was to evaluate the safety and effectiveness of a new angiographic system (Catheter 3.0 system) using a 5 French (Fr), large-bore angiography catheter, a 0.032-inch stiff guidewire, and a continuous flushing system in diagnostic cerebral angiography. This retrospective study included 30 consecutive patients who underwent transfemoral cerebral angiography using the Catheter 3.0 system from October 2019 to March 2020. As the control group, we included 30 consecutive patients examined before the Catheter 3.0 system was introduced. Procedural outcomes, including technical success, procedure time, dose metrics, procedure-related complications, and image quality were reviewed and analyzed. All transfemoral cerebral angiographies were performed for a diagnosis of unruptured intracranial aneurysms. The Catheter 3.0 system showed a significantly shorter fluoroscopy time (6.2 vs. 9.7 minutes, P=0.008) and lower fluoroscopy dose (387.2 vs. 614.4, P=0.002) compared with the conventional 4-Fr catheter system. The Catheter 3.0 system also showed better results in terms of procedural time (21.0 vs. 22.5 minutes, P=0.072) and technical success rate (98.1% vs. 94.0%, P=0.078), although a statistical significance was not reached. The complication rate and qualitative assessment of the digital subtraction angiography (DSA) image quality were similar between the two groups. The Catheter 3.0 system using a 5 Fr catheter with a large inner diameter was convenient, effective, and safe compared with the conventional system in diagnostic cerebrovascular angiography.

Optimizing Small, Low-Risk, Unruptured Intracranial Aneurysm Treatment Using Game Theory.

The incidental diagnosis of unruptured intracranial aneurysms has been increasing in the past several decades. A significant proportion represent small, low-risk, unruptured intracranial aneurysms for which there is equipoise on whether to offer treatment or conservative management. Given this uncertainty, patients may not always be comfortable with their physicians' recommendations. Herein, we use game theory to study the interactions between physicians and patients to determine how conflict and cooperation affect the management of small, low-risk, unruptured intracranial aneurysms. We constructed a game theory model of the interaction between physicians and patients with respect to decision-making for a small, low-risk, unruptured intracranial aneurysm in an asymptomatic patient when there is perceived equipoise between whether to treat or manage conservatively. Assuming that both the physician and patient are rational and eliciting individual patient preferences is not practical, the physician should play the game based on an ex ante probability of meeting a patient with a certain type of preference. This recommendation means that the expectations of the physician regarding the patient's preferences should guide the decision to offer treatment or conservative management as a first option for a small, asymptomatic, low-risk, unruptured intracranial aneurysm for which there is clinical equipoise.

Clipping of unruptured intracranial aneurysms in patients older than sixty: An age-based analysis

ObjectiveThe diagnosis of unruptured intracranial aneurysms (UIAs) is being made more frequently in elderly patients. The goal of this study is to evaluate complications and clinical outcome in patients ≥ 60 years-old who underwent clipping of UIAs. MethodsWe performed a retrospective cohort study. Clinical outcome (modified Rankin scale score) was determined at the latest clinical follow-up. Complications and outcomes were compared between age groups (60–69, 70–80) and subgroups (60–64, 65–69, 70–74, and >75). ResultsThe study population consisted of 255 patients (range 60–80 years-old) who underwent 262 clipping procedures for UIAs. Mean follow-up duration was 15.6 months (± 27.5). Major complications occurred in 20 patients (7.6%) and mortality in 3 patients (1.1%). Medical complications occurred in 26 patients (10%). Mean length of hospital-stay was 4.7 days (± 5.8). 89.6% were discharged to home. 87.8% had a favorable clinical outcome. The 70–80 age group had significantly more complications (P = 0.03) than the 60–69 group and a significantly longer hospital stay (6.02 vs. 4.3 days, P = 0.04). The older group was less likely to discharge to home and more likely to require rehabilitation (P = 0.002). Favorable clinical outcome did not significantly differ between the two groups (85.7% vs. 88.4%, P = 0.56). There was a trend for increasing complications from the younger to older subgroups (P = 0.008) and a reduction in the likelihood to discharge to home (P < 0.0001). The rate of ultimate favorable clinical outcome did not differ significantly between subgroups (P = 0.79). ConclusionAlthough complications, length of hospital-stay, and discharge to non-home destinations increase with older age, the majority of patients ≥ 60 may have favorable clinical outcomes.

Outcome of Patients with Multiple Intracranial Aneurysms after Subarachnoid Hemorrhage and Future Risk of Rupture of Unruptured Aneurysm.

The purpose was to study the risk of rupture of unruptured intracranial aneurysms (UIAs) of patients with multiple intracranial aneurysms after subarachnoid hemorrhage (SAH), in a long-term follow-up study, from variables known at baseline. Future rupture risk was compared in relation to outcome after SAH. The series consists of 131 patients with 166 UIAs and 2854 person-years of follow-up between diagnosis of UIA and its rupture, death or the last follow-up contact. These were diagnosed before 1979, when UIAs were not treated in our country. Those patients with a moderate or severe disability after SAH, according to the Glasgow Outcome Scale, had lower rupture rates of UIA than those with a good recovery or minimal disability (4/37 or 11%, annual UIA rupture rate of 0.5% (95% confidence interval (CI) 0.1–1.3%) during 769 follow-up years vs. 27/94 or 29%, 1.3% (95% CI 0.9–1.9%) during 2085 years). Those with a moderate or severe disability differed from others by their older age. Those with a moderate or severe disability tended to have a decreased cumulative rate of aneurysm rupture (log rank test, p = 0.066) and lower relative risk of UIA rupture (hazard ratio 0.39, 95% CI 0.14–1.11, p = 0.077). Multivariable hazard ratios showed at least similar results, suggesting that confounding factors did not have a significant effect on the results. The results of this study without treatment selection of UIAs suggest that patients with a moderate or severe disability after SAH have a relatively low risk of rupture of UIAs. Their lower treatment indication may also be supported by their known higher treatment risks.

Application of 3.0T Time-of-flight Magnetic Resonance Angiography with Sparse Undersampling and Iterative Reconstruction in the Diagnosis of Unruptured Intracranial Aneurysms

To evaluate the diagnostic value of 3.0T time-of-flight MR angiography with sparse undersampling and iterative reconstruction (TOFu-MRA) for unruptured intracranial aneurysms (UIAs) on the basis of using digital subtraction angiography (DSA) as the reference standard. A total of 65 patients with suspected UIAs were prospectively enrolled and all patients underwent TOFu-MRA and DSA. Relying on DSA as the reference standard, the sensitivity (SEN), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) of using TOFu-MRA in UIA diagnosis were calculated, and the inter-observer agreement between two doctors was determined. Comparison of maximum intensity projection (MIP) and volume rendering (VR) image datasets was made to evaluate the agreement between DSA results and TOFu-MRA in the measurement of UIA morphological parameters, including the neck width (D neck), height (H) , and width (D width) of UIAs. The study covered 55 UIAs from 46 patients. The SEN, SPE, PPV and NPV of the two doctors using TOFu-MRA in UIA diagnosis were as follows: (95.7%, 95.7%), (94.7%, 94.7%), (97.8%, 97.8%) and (90.0%, 90.0%), respectively for patient-based assessment; (96.4%, 94.5%), (94.7%, 94.7%), (98.1%, 98.1%) and (90.0%, 85.7%), respectively, for aneurysm-based assessment. There is a strong inter-observer agreement (Kappa=0.93 for patient-based assessment and 0.96 for aneurysm-based assessment) between the two doctors. Moreover, Bland-Altman analysis showed that more than 95% points fell within the limits of agreement (LoA), suggesting strong agreement between the two examination methods for the measurement of UIAs morphological parameters. TOFu-MRA showed good diagnostic efficacy for UIAs and the results were in good agreement with those of DSA, the reference standard, for assessing UIA morphological parameter. TOFu-MRA can be used as a first choice for noninvasive diagnostic evaluation of UIAs.

Added diagnostic values of three-dimensional high-resolution proton density-weighted magnetic resonance imaging for unruptured intracranial aneurysms in the circle-of-Willis: Comparison with time-of-flight magnetic resonance angiography.

Advanced imaging methods can enhance the identification of aneurysms of the infundibula, which can reduce unnecessary follow-ups or further work-up, fear, and anxiety in patients. This study aimed to evaluate the added diagnostic value of three-dimensional proton density-weighted vessel wall magnetic resonance imaging (3D-PD MRI) in identifying aneurysms from index lesions refer to vascular bulging lesions without vessels arising from the apex, observed using volume-rendered TOF-MRA in the circle-of-Willis compared with time-of-flight magnetic resonance angiography (TOF-MRA). Retrospective. A total of 299 patients who underwent 3D-PD MRI, digital subtraction angiography (DSA), and TOF-MRA between January 2012 and December 2016 were retrospectively enrolled in this study. 3 Tesla, 3D-PD MRI. Three neuroradiologists independently evaluated TOF-MRA and 3D-PD MRI combined with TOF-MRA for the determination of intracranial aneurysms in patients with index lesions within the circle of Willis. Final diagnoses were made by another neuroradiologist and neurointerventionist in consensus using DSA as the reference standard. The diagnostic performance and proportions of undetermined lesions on TOF-MRA and 3D-PD MRI with TOF-MRA were assessed based on the final diagnoses. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for the diagnosis of unruptured intracranial aneurysms were calculated for each imaging modality. Of 452 lesions identified on volume-rendered TOF-MRA images, 173 (38%) aneurysms and 276 (61%) infundibula were finally diagnosed on DSA. 3D-PD MRI with TOF-MRA showed superior diagnostic performance (p = .001; accuracy, 85.5% versus 95.4%), superior area under the receiver operating characteristic curve over TOF-MRA (p = .001; 0.837 versus 0.947), and a lower proportion of undetermined lesions than TOF-MRA (p = .001; 25.1% versus 2.3%). For unruptured intracranial aneurysms in the circle of Willis, 3D-PD MRI can complement TOF-MRA to improve diagnostic performance and lower the proportion of undetermined lesions.

Quality of Life of Patients with Unruptured Intracranial Aneurysms Before and After Endovascular Coiling: A HEAT Trial Secondary Study and Systematic Review of the Literature

The study of quality of life (QOL) in patients with asymptomatic diseases receiving interventional treatment provides an essential metric for the assessment of procedural benefits in the surgical patient population. In this study, we analyzed QOL data collected from patients with unruptured intracranial aneurysms (UIAs) before and after endovascular coiling in the HEAT Trial, alongside a systematic review on QOL in unruptured brain aneurysms. HEAT was a randomized controlled trial comparing recurrence rates in aneurysms treated with either bare platinum coils or hydrogel coils. Patients enrolled in this trial completed a short form-36 (SF-36) QOL questionnaire before treatment and at the 3- to 12- and 18- to 24-month follow-ups. The change in QOL before and after treatment was assessed. Regression analysis evaluated the effect of select baseline characteristics on QOL change. A total of 270 patients were eligible for analysis. There was an increase in the role physical (P= 0.043), vitality (P= 0.022), and emotional well-being (P < 0.001) QOL components at the 18- to 24-month follow-up compared with baseline scores. Regression analysis showed that age younger than 60 and absence of serious adverse events were associated with improved social functioning and vitality. The literature review showed a mixed effect of intervention on QOL in patients with UIAs. Our analysis has revealed that patients with 3- to 14-mm UIAs had improvements in some physical and emotional components of QOL at 18-24 months following aneurysm coiling in the HEAT study. The literature remains indeterminate on this issue. Further studies are needed to better understand the effects of the diagnosis of UIAs and their treatment on QOL.

Smoking habits and detection rate of unruptured intracranial aneurysms and incidence rate of subarachnoid haemorrhage in Norway between 2008 and 2015

ObjectiveThe aim of this study was to investigate the detection rate of unruptured intracranial aneurysms (UIAs) and incidence of aneurysmal subarachnoid haemorrhage (SAH) in relation to the rapidly changing smoking rates in Norway between 2008 and 2015.MethodsThe registry-based study included all patients (≥ 16 years old) admitted to a hospital in Norway between 2008 and 2015 with a primary diagnosis of aneurysmal SAH or an outpatient diagnosis of UIAs. Age group–specific and total detection rate of UIAs and incidence rate of SAH over the years were calculated. Age group–specific data on smoking habits was retrieved from a national annual survey representative of the whole Norwegian population.ResultsThe rate of daily smokers decreased by 48% between 2008 and 2015. The detection rate of UIAs decreased by 47% from 17.3 in 2008 to 9.3 per 100,000 persons in 2015, and the incidence of SAH decreased by 30% from 11.3 in 2008 to 7.9 per 100,000 persons in 2015. The average annual decline in prevalence of daily smoking, UIA detection rate, and SAH incidence was 6.9%, 6.7%, and 4.3% per year, respectively. Multinomial logistic regression analyses revealed that the correlation between the decline in estimated daily smoking rates and decline in detection rate of UIAs (hazard ratio 52.5 CI = (14.9,∞), p < 0.00001) and incidence of SAH (hazard ratio 11.8 CI=(5.6,32.5), p < 0.00001) are statistically significant. The association is particularly strong in young and middle-aged cohorts (< 66 years old).ConclusionIt is likely that reducing cigarette smoking on a population-based level strongly reduces the rates of UIAs and SAH.

Retrospective application of risk scores to ruptured intracranial aneurysms: would they have predicted the risk of bleeding?

As the incidental diagnosis of unruptured intracranial aneurysms has been increasing, several scores were developed to predict risk of rupture and growth to guide the management choice. We retrospectively applied these scores to a multicenter series of patients with subarachnoid hemorrhage to test whether they would have predicted the risk of bleeding in the event of aneurysm discovery previous to its rupture. Demographical, clinical, and radiological information of 245 adults were retrieved from two neurovascular centers' database. Data were pooled and PHASES, UCAS, and ELAPSS scores were retrospectively calculated for the whole population and their performances in identifying aneurysms at risk of rupture were compared. Mean PHASES, UCAS, and ELAPSS scores were 5.12 ± 3.08, 5.09 ± 2.62, and 15.88 ± 8.07, respectively. Around half (46%) of patients would have been assigned to the low- or very low-risk class (5-year rupture risk < 1%) in PHASES. Around 28% of patients would have been in a low-risk class, with a probability of 3-year rupture risk < 1% according to UCAS. Finally, ELAPSS score application showed a wider distribution among the risk classes, but a significant proportion of patients (45.5%) lie in the low- or intermediate-risk class for aneurysm growth. A high percentage of patients with ruptured aneurysms in this multicenter cohort would have been assigned to the lower risk categories for aneurysm growth and rupture with all the tested scores if they had been discovered before the rupture. Based on these observations, physicians should be careful about drawing therapeutic conclusions solely based on application of these scores.

Decision Making Among Patients with Unruptured Aneurysms: A Qualitative Analysis of Online Patient Forum Discussions

Deciding to treat unruptured intracranial aneurysms (UIA) involves discussion with patients about outcomes data and personal attitudes toward risk of rupture versus procedural complication risk. We performed a qualitative analysis of online interpatient discussions to investigate perspectives on medical decision making. On an aneurysm-specific forum, we identified patient conversation threads created between December 3, 2016 and December 3, 2018 containing discussion of medical decision making. These threads were analyzed using an adapted grounded-theory approach. Two researchers coded each thread and discussed discrepancies until consensus was reached. Coded content was analyzed to identify emergent themes. We analyzed 40 threads from a foundation-sponsored intracranial aneurysm-specific patient forum in the public domain. There were 110 user accounts, contributing 527 posts of average length 108 words. Fifty-seven users described diagnosis of UIA without history of rupture, and 20 described presentation with rupture. Patients 1) felt fortunate for diagnosis with UIA but were challenged by decision making and concern for rupture, 2) desired treatment by providers with large case volumes, clear communication, and an unbiased approach to decision making, 3) acted on qualitative understandings of individual risk, 4) considered psychological, social, and clinical factors in forming preferences for management, 5) sought information for purposes other than informing decision making, and 6) regained control through decision-making processes. This is the first ethnographic account of decision making among patients with UIAs. Newly diagnosed patients explored treatment options using online forums. They faced ambiguity in identifying optimal management, creating apprehension and decisional conflict. Further research is required to improve risk communication and individualized decision making for patients with UIAs.

Abstract TP188: Trends in Costs Associated With Endovascular and Surgical Treatments for Unruptured Intracranial Aneurysm Among Commercially Insured Patients

Objectives: Limited studies have examined economic outcomes of endovascular coiling (EVC) and/ or surgical clipping (SC) for unruptured intracranial aneurysm (UIA) from a payer perspective. This study evaluated trends in payments for index admission and 365-day follow-up (including index admission) among UIA patients treated with EVC or SC. Methods: A retrospective analysis of Truven MarketScan® Commercial Claims and Encounters (CCAE) database was conducted. The study sample included patients aged ≥ 18 years with a diagnosis of UIA who underwent EVC or SC between 2011 and 2016 (index hospitalization). The following exclusion criteria were applied: patients with a history of subarachnoid hemorrhage (SAH) or EVC/SC treatment in 12 months baseline; concurrent diagnosis of SAH during index hospitalization or lack of continuous enrollment in 12 months baseline period. Using Mann-Kendall test, we examined trends in payments for index admission and 365-day all-cause healthcare utilization (medical services and prescription). All costs were adjusted to 2016 US dollar. Results: A total of 3,294 patients met the eligibility criteria. The mean age of patients was 52.53 years (SD= 8.64) and 76.56% were female. The proportions of patients treated with EVC (vs. SC) increased from 67.80% in 2011 to 75.84% in 2016 (p= 0.01). The average index admission cost was $54,853 and the mean 365-day follow-up cost was $89,398. Mean index admission cost was $52,163 in 2011 and $64,193 in 2016 (p= 0.19). However, mean 365-day all-cause follow-up costs increased from $87,741 in 2011 to $94,096 in 2016 (p= 0.04). Conclusions: The 365-day all-cause follow-up costs associated with endovascular and surgical treatment among UIA patients increased significantly over the study period. There is significant economic burden for UIA patients undergoing neurointerventional procedures.

National trends in cerebral bypass for unruptured intracranial aneurysms: a National (Nationwide) Inpatient Sample analysis of 1998-2015.

OBJECTIVEThe development and recent widespread dissemination of flow diverters may have reduced the utilization of surgical bypass procedures to treat complex or giant unruptured intracranial aneurysms (UIAs). The aim of this retrospective cohort study was to observe trends in cerebral revascularization procedures for UIAs in the United States before and after the introduction of flow diverters by using the National (Nationwide) Inpatient Sample (NIS).METHODSThe authors extracted data from the NIS database for the years 1998-2015 using the ICD-9/10 diagnostic and procedure codes. Patients with a primary diagnosis of UIA with a concurrent bypass procedure were included in the study. Outcomes and hospital charges were analyzed.RESULTSA total of 216,212 patients had a primary diagnosis of UIA during the study period. The number of patients diagnosed with a UIA increased by 128% from 1998 (n = 7718) to 2015 (n = 17,600). Only 1328 of the UIA patients (0.6%) underwent cerebral bypass. The percentage of patients who underwent bypass in the flow diverter era (2010-2015) remained stable at 0.4%. Most patients who underwent bypass were white (51%), were female (62%), had a median household income in the 3rd or 4th quartiles (57%), and had private insurance (51%). The West (33%) and Midwest/North Central regions (30%) had the highest volume of bypasses, whereas the Northeast region had the lowest (15%). Compared to the period 1998-2011, bypass procedures for UIAs in 2012-2015 shifted entirely to urban teaching hospitals (100%) and to an elective basis (77%). The median hospital stay (9 vs 3 days, p < 0.0001), median hospital charges ($186,746 vs $66,361, p < 0.0001), and rate of any complication (51% vs 17%, p < 0.0001) were approximately threefold higher for the UIA patients with bypass than for those without bypass.CONCLUSIONSDespite a significant increase in the diagnosis of UIAs over the 17-year study period, the proportion of bypass procedures performed as part of their treatment has remained stable. Therefore, advances in endovascular aneurysm therapy do not appear to have affected the volume of bypass procedures performed in the UIA population. The authors' findings suggest a potentially ongoing niche for bypass procedures in the contemporary treatment of UIAs.

Abstract WP122: Risk of Intracranial Hemorrhage and National Trends of Delivery Methods of Pregnant Women With Diagnosis of Unruptured Intracranial Aneurysm

Introduction: Understanding the risk of aneurysmal subarachnoid hemorrhage in pregnant women with known history of Unruptured Intracranial Aneurysm (UICA) could potentially impact the delivery method. Due to presumed risk of intrapartum aneurysm rupture, understanding practice patterns of delivery methods and related complication risk is of importance. Methods: We used Nationwide Inpatient Sample database (1998-2014) to identify all the hospitalizations for childbirth in women with and without history of UICA. Patients with intracranial vascular malformation and traumatic intracranial hemorrhage were excluded. The cohort of pregnant women with known history of UICA was compared with the cohort of those without history of UICA with univariate analysis. Results: A total of 323 patients with known history of UICA were hospitalized for childbirth compared to 13,669,848 with no history of UICA. Higher rates of intracranial hemorrhage was observed in history of UICA group compared to no history of UICA [subarachnoid hemorrhage (0.31% Vs 0.001%, p&lt;0.01), intracerebral hemorrhage (0.94% Vs 0.001%, p&lt;0.01), and non-specific intracranial hemorrhage (0.28% Vs 0.0004%, p&lt;0.01)]. UICA group had higher incidence of essential hypertension (6.9% Vs 1.1%, p&lt;0.01), pre-eclampsia (7.1% Vs 3.5%, p&lt;0.01), and eclampsia (0.6% Vs 0.07%, p&lt;0.01), and prevalence of smoking (8.23% Vs 3.95%, p&lt;0.01). The rate of cesarean section (78.8% Vs 29.6%, p&lt;0.01) and length of average hospital stay (3.76 Vs 2.57 days, p&lt;0.01) was higher in UICA group. UICA group had higher rates of major anesthesia complications (0.32% Vs 0.01%, p&lt;0.01), prolonged mechanical ventilation (1.2% Vs 0.04%, p&lt;0.01), and blood transfusion (3.12% Vs 0.75%, p&lt;0.01). 80% of UICA patients who had intracranial hemorrhage also had cesarean section. Conclusion: Women undergoing childbirth with known history of UICA have higher risk of intracranial hemorrhage, peripartum complications, and longer hospitalizations compared to women without a known UICA. Aggressive management of risk factors for aneurysm rupture including hypertension and smoking could potentially decrease the rupture risk. Further research is needed to understand whether delivery method has an impact on decreasing risk of rupture.

Abstract WP84: National Inpatient Sample Analysis of Unruptured Intracranial Aneurysms: Trends in Treatment and In-Hospital Complications 2002-2014

Introduction: Our objective was to determine trends in treatment preference and in-hospital complications of patients undergoing elective and non-elective treatment for unruptured intracranial aneurysms (UIA) in the United States over a 12-year period. Methods: We identified patients from the National Inpatient Sample database who were electively or non-electively admitted to the hospital with a primary ICD 9 diagnosis of unruptured intracranial aneurysm (437.3) from 2002 to 2014. We identified the method of treatment (surgical clipping or endovascular coiling) and studied in-hospital complications. Results: We identified 111,811 patients with UIAs between 2002 to 2014. Of these patients, 89,599 (80.1%) of patients were electively admitted. Approximately 47% (42,112) of patients underwent surgical clipping, while 53% (47,487) of patients underwent endovascular coiling. Of 22,212 patients who were admitted non-electively, 38.6% (8570) patients underwent surgical clipping and 61.4% (13,642) underwent endovascular coiling. There was a significantly higher proportion of patients treated with endovascular coiling for non-electively admitted patients as compared to elective admissions. For electively treated UIAs there were no significant differences in in-hospital mortality between the two treatment groups. Iatrogenic cerebrovascular accidents and intracranial hemorrhage were significantly less common in the endovascular coiling group throughout the study period. For non-electively treated UIAs, there was no significant difference in hospital mortality over the 12-year period. The rate of iatrogenic cerebrovascular accidents was generally lower for endovascular coiling with the exception of 2003. Endovascular coiling resulted in a significantly lower rate of iatrogenic cerebrovascular accidents in 2004 and 2008-2012. Intracranial hemorrhage was significantly less common in the endovascular group in 2004 and 2008-2014. Conclusions: Endovascular therapy has lower rates of in-hospital iatrogenic cerebrovascular accidents, and similar rates of mortality. The rate of endovascular and surgical therapies has plateaued since approximately 2005.

A New DICOM Viewer System for the Comparative Diagnosis of Unruptured Intracranial Aneurysms

A New DICOM Viewer System for the Comparative Diagnosis of Unruptured Intracranial Aneurysms