A trial on unruptured intracranial aneurysms (the TEAM trial): results, lessons from a failure and the necessity for clinical care trials

Understanding the role of induction, intensions and extensions in pragmatic clinical research and practice

BACKGROUND

Pragmatic clinical research methods are poorly understood, but essential to practice outcome-based medical or surgical care. Pragmatic research aims to verify the connections between medical knowledge and the reality of practice. Its methods can be understood by reviewing the problems of induction, as well as the related linguistic and mathematical notions of intensions and extensions.

METHODS

We briefly review the source of problems with using inductive methods to gain knowledge, and the relationships between language, mathematics and reality. We discuss linguistic 'sense' and 'reference', and the set-theory terms 'intensions' and 'extensions', which define the relationship between individuals and whichever pertinent collection these individuals comprise. Both concepts are essential to understand pragmatic medical research and evidence-based practice.

RESULTS

Pragmatic clinical research can be explained in terms of testing (in reality) the repeatability of various inductive referential and inferential steps used in clinical practice - from reliability, diagnostic accuracy, and prognostic studies to pragmatic trials. All pragmatic studies aim to verify the relationship between the extensions of the notions of symptoms, diagnoses, prognoses, treatments, and outcomes. The concepts of intensions and extensions also serve to understand 'statistical significance' in analyzing trial results, as well as problems related to eligibility criteria and subgroup analyses. The results of clinical studies can be generalized to the extent that they have been tested in numerous and widely different individuals.

CONCLUSION

The notions of sense and reference, and of intensions and extensions, help explain the role pragmatic clinical research methods can play in optimizing care.

Ethical Problems of Observational Studies and Big Data Compared to Randomized Trials

The temptation to use prospective observational studies (POS) instead of conducting difficult trials (RCTs) has always existed, but with the advent of powerful computers and large databases, it can become almost irresistible. We examine the potential consequences, were this to occur, by comparing two hypothetical studies of a new treatment: one RCT, and one POS. The POS inevitably submits more patients to inferior research methodology. In RCTs, patients are clearly informed of the research context, and 1:1 randomized allocation between experimental and validated treatment balances risks for each patient. In POS, for each patient, the risks of receiving inferior treatment are impossible to estimate. The research context and the uncertainty are down-played, and patients and clinicians are at risk of becoming passive research subjects in studies performed from an outsider's view, which potentially has extraneous objectives, and is conducted without their explicit, autonomous, and voluntary involvement and consent.

Reliability of study endpoint adjudication in a pragmatic trial on brain arteriovenous malformations

BACKGROUND

The results of a clinical trial are given in terms of primary and secondary outcomes that are obtained for each patient. Just as an instrument should provide the same result when the same object is measured repeatedly, the agreement of the adjudication of a clinical outcome between various raters is fundamental to interpret study results. The reliability of the adjudication of study endpoints determined by examination of the electronic case report forms of a pragmatic trial has not previously been tested.

METHODS

The electronic case report forms of 62/434 (14%) patients selected to be observed in a study on brain AVMs were independently examined twice (4 weeks apart) by 8 raters who judged whether each patient had reached the following study endpoints: (1) new intracranial hemorrhage related to AVM or to treatment; (2) new non-hemorrhagic neurological event; (3) increase in mRS ≥1; (4) serious adverse events (SAE). Inter and intra-rater reliability were assessed using Gwet's AC1 (κG) statistics, and correlations with mRS score using Cramer's V test.

RESULTS

There was almost perfect agreement for intracranial hemorrhage (92% agreement; κG = 0.84 (95%CI: 0.76-0.93), and substantial agreement for SAEs (88% agreement; κG = 0.77 (95%CI: 0.67-0.86) and new non-hemorrhagic neurological event (80% agreement; κG = 0.61 (95%CI: 0.50-0.72). Most endpoints correlated (V = 0.21-0.57) with an increase in mRS of ≥1, an endpoint which was itself moderately reliable (76% agreement; κG = 0.54 (95%CI: 0.43-0.64).

CONCLUSION

Study endpoints of a pragmatic trial were shown to be reliable. More studies on the reliability of pragmatic trial endpoints are needed.

Medical management and surgery versus medical management alone for symptomatic cerebral cavernous malformation (CARE): a feasibility study and randomised, open, pragmatic, pilot phase trial

BACKGROUND

The highest priority uncertainty for people with symptomatic cerebral cavernous malformation is whether to have medical management and surgery or medical management alone. We conducted a pilot phase randomised controlled trial to assess the feasibility of addressing this uncertainty in a definitive trial.

METHODS

The CARE pilot trial was a prospective, randomised, open-label, assessor-blinded, parallel-group trial at neuroscience centres in the UK and Ireland. We aimed to recruit 60 people of any age, sex, and ethnicity who had mental capacity, were resident in the UK or Ireland, and had a symptomatic cerebral cavernous malformation. Computerised, web-based randomisation assigned participants (1:1) to medical management and surgery (neurosurgical resection or stereotactic radiosurgery) or medical management alone, stratified by the neurosurgeon's and participant's consensus about the intended type of surgery before randomisation. Assignment was open to investigators, participants, and carers, but not clinical outcome event adjudicators. Feasibility outcomes included site engagement, recruitment, choice of surgical management, retention, adherence, data quality, clinical outcome event rate, and protocol implementation. The primary clinical outcome was symptomatic intracranial haemorrhage or new persistent or progressive non-haemorrhagic focal neurological deficit due to cerebral cavernous malformation or surgery during at least 6 months of follow-up. We analysed data from all randomly assigned participants according to assigned management. This trial is registered with ISRCTN (ISRCTN41647111) and has been completed.

FINDINGS

Between Sept 27, 2021, and April 28, 2023, 28 (70%) of 40 sites took part, at which investigators screened 511 patients, of whom 322 (63%) were eligible, 202 were approached for recruitment, and 96 had collective uncertainty with their neurosurgeon about whether to have surgery for a symptomatic cerebral cavernous malformation. 72 (22%) of 322 eligible patients were randomly assigned (mean recruitment rate 0·2 [SD 0·25] participants per site per month) at a median of 287 (IQR 67-591) days since the most recent symptomatic presentation. Participants' median age was 50·6 (IQR 38·6-59·2) years, 68 (94%) of 72 participants were adults, 41 (57%) were female, 66 (92%) were White, 56 (78%) had a previous intracranial haemorrhage, and 28 (39%) had a previous epileptic seizure. The intended type of surgery before randomisation was neurosurgical resection for 19 (26%) of 72, stereotactic radiosurgery for 44 (61%), and no preference for nine (13%). Baseline clinical and imaging data were complete for all participants. 36 participants were randomly assigned to medical management and surgery (12 to neurosurgical resection and 24 to stereotactic radiosurgery) and 36 to medical management alone. Three (4%) of 72 participants withdrew, one was lost to follow-up, and one declined face-to-face follow-up, leaving 67 (93%) retained at 6-months' clinical follow-up. 61 (91%) of 67 participants with follow-up adhered to the assigned management strategy. The primary clinical outcome occurred in two (6%) of 33 participants randomly assigned to medical management and surgery (8·0%, 95% CI 2·0-32·1 per year) and in two (6%) of 34 participants randomly assigned to medical management alone (7·5%, 1·9-30·1 per year). Investigators reported no deaths, no serious adverse events, one protocol violation, and 61 protocol deviations.

INTERPRETATION

This pilot phase trial exceeded its recruitment target, but a definitive trial will require extensive international engagement.

FUNDING

National Institute for Health and Care Research.

A Pragmatic Randomized Trial Comparing Surgical Clipping and Endovascular Treatment of Unruptured Intracranial Aneurysms

BACKGROUND AND PURPOSE

Surgical clipping and endovascular treatment are commonly used in patients with unruptured intracranial aneurysms. We compared the safety and efficacy of the 2 treatments in a randomized trial.

MATERIALS AND METHODS

Clipping or endovascular treatments were randomly allocated to patients with one or more 3- to 25-mm unruptured intracranial aneurysms judged treatable both ways by participating physicians. The study hypothesized that clipping would decrease the incidence of treatment failure from 13% to 4%, a composite primary outcome defined as failure of aneurysm occlusion, intracranial hemorrhage during follow-up, or residual aneurysms at 1 year, as adjudicated by a core lab. Safety outcomes included new neurologic deficits following treatment, hospitalization of >5 days, and overall morbidity and mortality (mRS > 2) at 1 year. There was no blinding.

RESULTS

Two hundred ninety-one patients were enrolled from 2010 to 2020 in 7 centers. The 1-year primary outcome, ascertainable in 290/291 (99%) patients, was reached in 13/142 (9%; 95% CI, 5%-15%) patients allocated to surgery and in 28/148 (19%; 95% CI, 13%-26%) patients allocated to endovascular treatments (relative risk: 2.07; 95% CI, 1.12-3.83; P = .021). Morbidity and mortality (mRS >2) at 1 year occurred in 3/143 and 3/148 (2%; 95% CI, 1%-6%) patients allocated to surgery and endovascular treatments, respectively. Neurologic deficits (32/143, 22%; 95% CI, 16%-30% versus 19/148, 12%; 95% CI, 8%-19%; relative risk: 1.74; 95% CI, 1.04-2.92; P = .04) and hospitalizations beyond 5 days (69/143, 48%; 95% CI, 40%-56% versus 12/148, 8%; 95% CI, 5%-14%; relative risk: 0.18; 95% CI, 0.11-0.31; P < .001) were more frequent after surgery.

CONCLUSIONS

Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of the primary outcome of treatment failure. Results were mainly driven by angiographic results at 1 year.

Management of Unruptured Intracranial Aneurysms and Brain Arteriovenous Malformations

OBJECTIVE

Managing a patient with an unruptured brain aneurysm or brain arteriovenous malformation (AVM) can lead to uncertainty about preventive treatment. While the bleeding risks are low, the morbidity or mortality associated with a hemorrhagic event is not insignificant. The objective of this article is to review the natural history of these vascular entities, the risk factors for hemorrhage, preventive treatment options, and the risks of treatment.

LATEST DEVELOPMENTS

Randomized trials to inform preventive treatment strategies for unruptured intracranial aneurysms and brain AVMs are ongoing. Higher angiographic obliteration rates of unruptured intracranial aneurysms have been reported with the flow-diversion technique compared with alternative standard techniques. One randomized trial for unruptured brain AVMs showed a higher rate of morbidity and mortality in patients who underwent interventional treatment compared with observation.

ESSENTIAL POINTS

The decision to treat a patient with a brain aneurysm should consider patient factors, the patient's life expectancy, aneurysm anatomical factors, and treatment risks. Patients with unruptured brain AVMs should be observed in light of recent clinical trial data or enrolled in an ongoing clinical trial.

Should Magnetic Resonance Angiography Be Used for Screening of Intracranial Aneurysm in Adults with Sickle Cell Disease?

Magnetic resonance imaging (MRI) is used in patients with sickle cell disease (SCD) to detect silent cerebral infarcts. MR angiography (MRA) can identify arterial stenoses and intracranial aneurysms (ICANs) associated with SCD. In this study, we aimed to estimate the prevalence of ICANs in asymptomatic adult patients with SCD referred from the SCD clinic for routine screening by MRI/MRA using a 3T-MRI scanner. Findings were independently reviewed by two neuroradiologists. Between 2016 and 2020, 245 asymptomatic adults with SCD were stratified according to genotype (SS/S-β0thalassemia and SC/Sβ+). ICANs were found in 27 patients (11%; 0.95 CI: 8-16%). ICANs were more frequent in SS/S-β0thalassemia patients (20/118 or 17%; 0.95 CI: 11-25%) than in SC/βb+ patients (7/127 or 6%; 0.95 CI: 2-11%; p = 0.007). Individuals with SCD (particularly SS/S-β0thalassemia) have a higher prevalence of ICANs than the general population. We believe that MRA should be considered in the current American Society of Hematology guidelines, which already contain a recommendation for MRI at least once in adult SCD patients. However, the clinical significance of preventive treatment of unruptured aneurysms remains controversial.

Development of the SAFETEA Scores for Predicting Risks of Complications of Preventive Endovascular or Microneurosurgical Intracranial Aneurysm Occlusion

BACKGROUND AND OBJECTIVES

Preventive unruptured intracranial aneurysm (UIA) occlusion can reduce the risk of subarachnoid hemorrhage, but both endovascular and microneurosurgical treatment carry a risk of serious complications. To improve individualized management decisions, we developed risk scores for complications of endovascular and microneurosurgical treatment based on easily retrievable patient, aneurysm, and treatment characteristics.

METHODS

For this multicenter cohort study, we combined individual patient data from patients with UIA aged 18 years or older undergoing preventive endovascular treatment (standard, balloon-assisted or stent-assisted coiling, Woven EndoBridge-device, or flow-diverting stent) or microneurosurgical clipping at one of the 10 participating centers from 3 continents between 2000 and 2018. The primary outcome was death from any cause or clinical deterioration from neurologic complications ≤30 days. We selected predictors based on previous knowledge about relevant risk factors and predictor performance and studied the association between predictors and complications with logistic regression. We assessed model performance with calibration plots and concordance (c) statistics.

RESULTS

Of the 1,282 included patients, 94 (7.3%) had neurologic symptoms that resolved <30 days, 140 (10.9%) had persisting neurologic symptoms, and 6 died (0.5%). At 30 days, 52 patients (4.1%) were dead or dependent. Predictors of procedural complications were size of aneurysm, aneurysm location, familial subarachnoid hemorrhage, earlier atherosclerotic disease, treatment volume, endovascular modality (for endovascular treatment) or extra aneurysm configuration factors (for microneurosurgical treatment, branching artery from aneurysm neck or unfavorable dome-to-neck ratio), and age (acronym: SAFETEA). For endovascular treatment (n = 752), the c-statistic was 0.72 (95% CI 0.67-0.77) and the absolute complication risk ranged from 3.2% (95% CI 1.6%-14.9%; ≤1 point) to 33.1% (95% CI 25.4%-41.5%; ≥6 points). For microneurosurgical treatment (n = 530), the c-statistic was 0.72 (95% CI 0.67-0.77) and the complication risk ranged from 4.9% (95% CI 1.5%-14.9%; ≤1 point) to 49.9% (95% CI 39.4%-60.6%; ≥6 points).

DISCUSSION

The SAFETEA risk scores for endovascular and microneurosurgical treatment are based on 7 easily retrievable risk factors to predict the absolute risk of procedural complications in patients with UIAs. The scores need external validation before the predicted risks can be properly used to support decision-making in clinical practice.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that SAFETEA scores predict the risk of procedural complications after endovascular and microneurosurgical treatment of unruptured intracranial aneurysms.

European Stroke Organisation (ESO) guidelines on management of unruptured intracranial aneurysms

Unruptured intracranial aneurysms (UIA) occur in around 3% of the population. Important management questions concern if and how to perform preventive UIA occlusion; if, how and when to perform follow up imaging and non-interventional means to reduce the risk of rupture. Using the Standard Operational Procedure of ESO we prepared guidelines according to GRADE methodology. Since no completed randomised trials exist, we used interim analyses of trials, and meta-analyses of observational and case-control studies to provide recommendations to guide UIA management. All recommendations were based on very low evidence. We suggest preventive occlusion if the estimated 5-year rupture risk exceeds the risk of preventive treatment. In general, we cannot recommend endovascular over microsurgical treatment, but suggest flow diverting stents as option only when there are no other low-risk options for UIA repair. To detect UIA recurrence we suggest radiological follow up after occlusion. In patients who are initially observed, we suggest radiological monitoring to detect future UIA growth, smoking cessation, treatment of hypertension, but not treatment with statins or acetylsalicylic acid with the indication to reduce the risk of aneurysm rupture. Additionally, we formulated 15 expert-consensus statements. All experts suggest to assess UIA patients within a multidisciplinary setting (neurosurgery, neuroradiology and neurology) at centres consulting >100 UIA patients per year, to use a shared decision-making process based on the team recommendation and patient preferences, and to repair UIA only in centres performing the proposed treatment in >30 patients with (ruptured or unruptured) aneurysms per year per neurosurgeon or neurointerventionalist. These UIA guidelines provide contemporary recommendations and consensus statement on important aspects of UIA management until more robust data come available.

Flow Diversion in the Treatment of Intracranial Aneurysms: A Pragmatic Randomized Care Trial

BACKGROUND AND PURPOSE

Flow diversion is a recent endovascular treatment for intracranial aneurysms. We compared the safety and efficacy of flow diversion with the alternative standard management options.

MATERIALS AND METHODS

A parallel group, prerandomized, controlled, open-label pragmatic trial was conducted in 3 Canadian centers. The trial included all patients considered for flow diversion. A Web-based platform 1:1 randomly allocated patients to flow diversion or 1 of 4 alternative standard management options (coiling with/without stent placement, parent vessel occlusion, surgical clipping, or observation) as prespecified by clinical judgment. Patients ineligible for alternative standard management options were treated with flow diversion in a registry. The primary safety outcome was death or dependency (mRS > 2) at 3 months. The composite primary efficacy outcome included the core lab-determined angiographic presence of a residual aneurysm, aneurysm rupture, progressive mass effect during follow-up, or death or dependency (mRS > 2) at 3-12 months.

RESULTS

Between May 2011 and November 2020, three hundred twenty-three patients were recruited: Two hundred seventy-eight patients (86%) had treatment randomly allocated (139 to flow diversion and 139 to alternative standard management options), and 45 (14%) received flow diversion in the registry. Patients in the randomized trial frequently had unruptured (83%), large (52% ≥10 mm) carotid (64%) aneurysms. Death or dependency at 3 months occurred in 16/138 patients who underwent flow diversion and 12/137 patients receiving alternative standard management options (relative risk, 1.33; 95% CI, 0.65-2.69; P = .439). A poor primary efficacy outcome was found in 30.9% (43/139) with flow diversion and 45.6% (62/136) of patients receiving alternative standard management options, with an absolute risk difference of 14.7% (95% CI, 3.3%-26.0%; relative risk, 0.68; 95% CI, 0.50-0.92; P = .014).

CONCLUSIONS

For patients with mostly unruptured, large, anterior circulation (carotid) aneurysms, flow diversion was more effective than the alternative standard management option in terms of angiographic outcome.

Clinical Trials of Microsurgery for Cerebral Aneurysms: Past and Future

BACKGROUND

New findings and research regarding the microsurgical treatment of intracerebral aneurysms (IAs) continue to advance even in the era of endovascular therapies. Research in the past 2 decades has continued to revolve around the question of whether open surgery or endovascular treatment is preferable. The answer remains both complex and in flux.

OBJECTIVE

This review focuses on microsurgery, reflects on the research decisions of previous landmark studies, and proposes future study designs that may further our understanding of IAs and how best to treat them.

RESULTS

The future of IA research may include a combination of pragmatic trials, artificial intelligence integrated tools, and mining of large data sets, in addition to the publication of high-quality single-center studies.

CONCLUSIONS

The future will likely emphasize testing innovative techniques, looking at granular patient data, and considering every patient encounter as a potential source of knowledge, creating a system in which data are updated daily because each patient interaction contributes to answering important research questions.

Recruitment in a pragmatic randomized trial on the management of unruptured intracranial aneurysms

OBJECTIVES

The Comprehensive Aneurysm Management (CAM) study is a pragmatic trial designed to manage UIA patients within a care research framework.

METHOD

CAM is an all-inclusive study. Management options are allocated according to an algorithm combining pre-randomization and clinical judgment. Eligible patients are offered 1:1 randomized allocation of intervention versus conservative management and 1:1 randomization allocation of surgical versus endovascular treatment. Ineligible patients are registered. The primary outcome is survival without dependency (mRS<3) at 10 years. All UIA patients at one center are reported.

RESULTS

Between February 2020 and July 2021, 403 UIA patients were recruited: 179 (44%) in one of the RCTs and 224 (56%) in one of the registries. Conservative management was recommended for 205/403 patients (51%); of 198 (49%) patients considered for curative treatment, 159 (80%) were randomly allocated conservative (n=81) or curative treatment (n=78). These patients were younger and had larger aneurysms than those in the observation registry (P = .004). In 39/198 patients (20%), conservative management was not considered reasonable (17 patients were recommended endovascular, 2 surgery, and 20 the RCT comparing endovascular with surgical treatment). In total, 70 patients were recruited in the RCT comparing surgery and endovascular treatment. After informed discussion at time of consent, 141/159 patients (89%) agreed with the randomly allocated management plan, while 11% crossed-over to the alternative management option.

CONCLUSION

CAM was successfully integrated into routine practice. Meaningful conclusions can be obtained if multiple centers actively participate in the trial.

Repeat Resection in Recurrent Glioblastoma (3rGBM) Trial: a randomized care trial

BACKGROUND

The prognosis for patients with recurrent glioblastoma (GBM) is dismal, and the question of repeat surgery at time of recurrence is common. Re-operation in the management of these patients remains controversial, as there is no randomized evidence of benefit. An all-inclusive pragmatic care trial is needed to evaluate the role of repeat resection.

METHODS

3rGBM is a multicenter, pragmatic, prospective, parallel-group randomized care trial, with 1:1 allocation to repeat resection or standard care with no repeat resection. To test the hypothesis that repeat resection can improve overall survival by at least 3 months (from 6 to 9 months), 250 adult patients with prior resection of pathology-proven glioblastoma for whom the attending surgeon believes repeat resection may improve quality survival will be enrolled. A surrogate measure of quality of life, the number of days outside of hospital/nursing/palliative care facility, will also be compared. Centers are invited to participate without financial compensation and without contracts. Clinicians may apply to local authorities to approve an investigator-led in-house trial, using a common protocol, web-based randomization platform, and simple standardized case report forms.

DISCUSSION

The 3rGBM trial is a modern transparent care research framework with no additional risks, tests, or visits other than what patients would encounter in normal care. The burden of proof remains on repeat surgical management of recurrent GBM, because this management has yet to be shown beneficial. The trial is designed to help patients and surgeons manage the uncertainty regarding optimal care.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov. Unique identifier: NCT04838782.

Treatments for unruptured intracranial aneurysms

BACKGROUND

Unruptured intracranial aneurysms are relatively common lesions in the general population, with a prevalence of 3.2%, and are being diagnosed with greater frequency as non-invasive techniques for imaging of intracranial vessels have become increasingly available and used. If not treated, an intracranial aneurysm can be catastrophic. Morbidity and mortality in aneurysmal subarachnoid hemorrhage are substantial: in people with subarachnoid hemorrhage, 12% die immediately, more than 30% die within one month, 25% to 50% die within six months, and 30% of survivors remain dependent. However, most intracranial aneurysms do not bleed, and the best treatment approach is still a matter of debate.

OBJECTIVES

To assess the risks and benefits of interventions for people with unruptured intracranial aneurysms.

SEARCH METHODS

We searched CENTRAL (Cochrane Library 2020, Issue 5), MEDLINE Ovid, Embase Ovid, and Latin American and Caribbean Health Science Information database (LILACS). We also searched ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform from inception to 25 May 2020. There were no language restrictions. We contacted experts in the field to identify further studies and unpublished trials.

SELECTION CRITERIA

Unconfounded, truly randomized trials comparing conservative treatment versus interventional treatments (microsurgical clipping or endovascular coiling) and microsurgical clipping versus endovascular coiling for individuals with unruptured intracranial aneurysms.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion according to the above criteria, assessed trial quality and risk of bias, performed data extraction, and applied the GRADE approach to the evidence. We used an intention-to-treat analysis strategy.

MAIN RESULTS

We included two trials in the review: one prospective randomized trial involving 80 participants that compared conservative treatment to endovascular coiling, and one randomized controlled trial involving 136 participants that compared microsurgical clipping to endovascular coiling for unruptured intracranial aneurysms. There was no difference in outcome events between conservative treatment and endovascular coiling groups. New perioperative neurological deficits were more common in participants treated surgically (16/65, 24.6%; 15.8% to 36.3%) versus 7/69 (10.1%; 5.0% to 19.5%); odds ratio (OR) 2.87 (95% confidence interval (CI) 1.02 to 8.93; P = 0.038). Hospitalization for more than five days was more common in surgical participants (30/65, 46.2%; 34.6% to 58.1%) versus 6/69 (8.7%; 4.0% to 17.7%); OR 8.85 (95% CI 3.22 to 28.59; P < 0.001). Clinical follow-up to one year showed 1/48 clipped versus 1/58 coiled participants had died, and 1/48 clipped versus 1/58 coiled participants had become disabled (modified Rankin Scale > 2). All the evidence is of very low quality.

AUTHORS' CONCLUSIONS

There is currently insufficient good-quality evidence to support either conservative treatment or interventional treatments (microsurgical clipping or endovascular coiling) for individuals with unruptured intracranial aneurysms. Further randomized trials are required to establish if surgery is a better option than conservative management, and if so, which surgical approach is preferred for which patients. Future studies should include consideration of important characteristics such as participant age, gender, aneurysm size, aneurysm location (anterior circulation and posterior circulation), grade of ischemia (major stroke), and duration of hospitalizations.

Objective quantification of contrast enhancement of unruptured intracranial aneurysms: a high-resolution vessel wall imaging validation study

OBJECTIVE

High-resolution vessel wall imaging (HR-VWI) has emerged as a valuable tool in assessing unruptured intracranial aneurysms (UIAs). There is no standardized method to quantify contrast enhancement of the aneurysm wall. Contrast enhancement can be objectively measured as signal intensity (SI) or subjectively adjudicated. In this study, the authors compared the different methods to quantify wall enhancement of UIAs and determined the sensitivity and specificity of each method as a surrogate of aneurysm instability. They also compared SI quantification between scanners from different manufacturers.

METHODS

The University of Iowa HR-VWI Project database was analyzed. This database compiles patients with UIAs who prospectively underwent HR-VWI using a 3T MRI scanner. The mean and maximal SI values of the aneurysm wall, pituitary stalk, and genu of the corpus callosum were used to compare 3 different measurement methods: 1) aneurysm enhancement ratio AER = (SIwall post - SIwall pre)/SIwall pre; 2) aneurysm-to-pituitary stalk contrast ratio CRstalk = SIwall post/SIstalk post; and 3) aneurysm enhancement index AEI = ([SIwall post/SIbrain post] - [SIwall pre/SIbrain pre])/(SIwall pre/SIbrain pre) (where "pre" indicates precontrast images and "post" indicates postcontrast images). Size ≥ 7 mm was used as a surrogate of aneurysm instability for receiver operating characteristic (ROC) curve analysis. To determine if the objective quantification of SI varies among scanners from different manufacturers, 9 UIAs underwent the same HR-VWI protocol using a 3T General Electric (GE) scanner and a 3T Siemens scanner. Three UIAs also underwent a third scanning procedure on a unit with a different magnet strength (7T GE).

RESULTS

Eighty patients with 102 UIAs were included in the study. The mean age was 64.5 ± 12.2 years, and 64 (80%) patients were women. UIAs ≥ 7 mm had significantly higher SIs than smaller UIAs (< 7 mm): AER = 0.82 vs 0.49, p < 0.001; CRstalk = 0.84 vs 0.61, p < 0.001; and AEI = 0.81 vs 0.48, p < 0.001. ROC curves demonstrated optimal sensitivity of 81.5% for CRstalk ≥ 0.60, 75.9% for AEI ≥ 0.50, and 74.1% for AER ≥ 0.49. Intermanufacturer correlation between 3T GE and 3T Siemens MRI scanners for CRstalk using mean and maximal SI values was excellent (Pearson coefficients > 0.80, p < 0.001). A similar correlation was identified among the 3 UIAs that underwent 7T imaging.

CONCLUSIONS

CRstalk using maximal SI values was the most reliable objective method to quantify enhancement of UIAs on HR-VWI. The same ratios were obtained between different manufacturers and on scans obtained using magnets of different strengths.

Ethical care requires pragmatic care research to guide medical practice under uncertainty

BACKGROUND

The current research-care separation was introduced to protect patients from explanatory studies designed to gain knowledge for future patients. Care trials are all-inclusive pragmatic trials integrated into medical practice, with no extra tests, risks, or cost, and have been designed to guide practice under uncertainty in the best medical interest of the patient.

PROPOSED REVISION

Patients need a distinction between validated care, previously verified to provide better outcomes, and promising but unvalidated care, which may include unnecessary or even harmful interventions. While validated care can be practiced normally, unvalidated care should only be offered within declared pragmatic care research, designed to protect patients from harm. The validated/unvalidated care distinction is normative, necessary to the ethics of medical practice. Care trials, which mark the distinction and allow the tentative use of promising interventions necessarily involve patients, and thus the design and conduct of pragmatic care research must respect the overarching rule of care ethics "to always act in the best medical interest of the patient." Yet, unvalidated interventions offered in contexts of medical uncertainty cannot be prescribed or practiced as if they were validated care. The medical interests of current patients are best protected when unvalidated practices are restricted to a care trial protocol, with 1:1 random allocation (or "hemi-prescription") versus previously validated care, to optimize potential benefits and minimize risks for each patient.

CONCLUSION

Pragmatic trials can regulate medical practice by providing (i) a transparent demarcation between unvalidated and validated care; (ii) norms of medical conduct when using tests and interventions of yet unknown benefits in practice; and eventually (iii) a verdict regarding optimal care.

Practicing outcome-based medical care using pragmatic care trials

The current separation between medical research and care is an obstacle to essential aspects of good medical practice: the verification that care interventions actually deliver the good outcomes they promise, and the use of scientific methods to optimize care under uncertainty. Pragmatic care trials have been designed to address these problems. Care trials are all-inclusive randomized trials integrated into care. Every item of trial design is selected in the best medical interest of participating patients. Care trials can eventually show what constitutes good medical practice based on patient outcomes. In the meantime, care trials give clinicians and patients the scientific methods necessary for optimization of medical care when no one really knows what to do.We report the progress of 9 randomized care trials that were used to guide the endovascular or surgical management of 1212 patients with acute stroke, intracranial aneurysms, and arteriovenous malformations in a single center in an elective or acute care context. Care trials were used to address long-standing dilemmas regarding rival medical, surgical, or endovascular management options or to offer innovative instead of standard treatments. The trial methodology, by replacing unrepeatable treatment decisions by 1:1 randomized allocation whenever reliable knowledge was not available, had an immediate impact, transforming unverifiable dogmatic medical practice into verifiable outcome-based medical care. We believe the approach is applicable to all medical or surgical domains, but widespread adoption may require the revision of many currently prevalent views regarding the role of research in clinical practice.

Delayed thromboembolic events after coiling of unruptured intracranial aneurysms in a prospective cohort of 335 patients

BACKGROUND

Coiling is the first-line treatment for the management of unruptured intracranial aneurysms (UIAs), but delayed thromboembolic events (TEEs) can occur after such treatment. ARETA (Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm) is a prospective multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed TEEs in the UIA subgroup.

METHODS

Sixteen neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015. Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. Data were analyzed from participants with UIA treated by coiling or balloon-assisted coiling. We assessed the rates, timing, management, clinical outcomes, and risk factors for delayed TEEs using univariable and multivariable analyses.

RESULTS

The rate of delayed TEEs was 2.4% (95% CI 1.0% to 4.6%) in patients with unruptured aneurysms, with all events occurring in the week following the procedure. In multivariate analysis, two factors were associated with delayed TEEs: autosomal dominant polycystic kidney disease (ADPKD): 20.0% in patients with ADPKD vs 1.9% in patients without ADPKD (OR 27.3 (95% CI 3.9 to 190.2), p=0.0008) and post-procedure aneurysm remnant: 9.4% in patients with post-procedure aneurysm remnant vs 1.6% in patients with adequate occlusion (OR 9.9 (95% CI 1.0 to 51.3), p=0.006). We describe modalities of management as well as clinical outcomes.

CONCLUSIONS

Delayed TEE is a relatively rare complication after coiling of UIAs. In this series, all occurred in the week following the initial procedure. Two factors were associated with delayed TEE: ADPKD and aneurysm remnant at procedure completion.

CLINICAL TRIAL REGISTRATION

NCT01942512.

Comprehensive Aneurysm Management (CAM): An All-Inclusive Care Trial for Unruptured Intracranial Aneurysms

BACKGROUND

In the absence of randomized evidence, the optimal management of patients with unruptured intracranial aneurysms (UIA) remains uncertain.

METHODS

Comprehensive Aneurysm Management (CAM) is an all-inclusive care trial combined with a registry. Any patient with a UIA (no history of intracranial hemorrhage within the previous 30 days) can be recruited, and treatment allocation will follow an algorithm combining clinical judgment and randomization. Patients eligible for at least 2 management options will be randomly allocated 1:1 to conservative or curative treatment. Minimization will be used to balance risk factors, using aneurysm size (≥7 mm), location (anterior or posterior circulation), and age <60 years.

RESULTS

The CAM primary outcome is survival without neurologic dependency (modified Rankin Scale [mRS] score <3) at 10 years. Secondary outcome measures include the incidence of subarachnoid hemorrhage during follow-up and related morbidity and mortality; morbidity and mortality related to endovascular treatment or surgical treatment of the UIA at 1 year; overall morbidity and mortality at 1, 5, and 10 years; when relevant, duration of hospitalization; and, when relevant, discharge to a location other than home. The primary hypothesis for patients randomly allocated to at least 2 options, 1 of which is conservative management, is that active UIA treatment will reduce the 10-year combined neurologic morbidity and mortality (mRS score >2) from 24% to 16%. At least 961 patients recruited from at least 20 centers over 4 years will be needed for the randomized portion of the study.

CONCLUSIONS

Patients with unruptured intracranial aneurysms can be comprehensively managed within the context of an all-inclusive care trial.

Does Increasing Packing Density Using Larger Caliber Coils Improve Angiographic Results of Embolization of Intracranial Aneurysms at 1 Year: A Randomized Trial

BACKGROUND AND PURPOSE

The impact of increased aneurysm packing density on angiographic outcomes has not been studied in a randomized trial. We sought to determine the potential for larger caliber coils to achieve higher packing densities and to improve the angiographic results of embolization of intracranial aneurysms at 1 year.

MATERIALS AND METHODS

Does Embolization with Larger Coils Lead to Better Treatment of Aneurysms (DELTA) was an investigator-initiated multicenter prospective, parallel, randomized, controlled clinical trial. Patients had 4- to 12-mm unruptured aneurysms. Treatment allocation to either 15- (experimental) or 10-caliber coils (control group) was randomized 1:1 using a Web-based platform. The primary efficacy outcome was a major recurrence or a residual aneurysm at follow-up angiography at 12 ± 2 months adjudicated by an independent core lab blinded to the treatment allocation. Secondary outcomes included indices of treatment success and standard safety outcomes. Recruitment of 564 patients was judged necessary to show a decrease in poor outcomes from 33% to 20% with 15-caliber coils.

RESULTS

Funding was interrupted and the trial was stopped after 210 patients were recruited between November 2013 and June 2017. On an intent-to-treat analysis, the primary outcome was reached in 37 patients allocated to 15-caliber coils and 36 patients allocated to 10-caliber coils (OR = 0.931; 95% CI, 0.528-1.644; P = .885). Safety and other clinical outcomes were similar. The 15-caliber coil group had a higher mean packing density (37.0% versus 26.9%, P = .0001). Packing density had no effect on the primary outcome when adjusted for initial angiographic results (OR = 1.001; 95% CI, 0.981-1.022; P = .879).

CONCLUSIONS

Coiling of aneurysms randomized to 15-caliber coils achieved higher packing densities compared with 10-caliber coils, but this had no impact on the angiographic outcomes at 1 year, which were primarily driven by aneurysm size and initial angiographic results.

Procedural Clinical Complications, Case-Fatality Risks, and Risk Factors in Endovascular and Neurosurgical Treatment of Unruptured Intracranial Aneurysms: A Systematic Review and Meta-analysis

Importance

The risk of procedural clinical complications and the case-fatality rate (CFR) from preventive treatment of unruptured intracranial aneurysms varies between studies and may depend on treatment modality and risk factors.

Objective

To assess current procedural clinical 30-day complications and the CFR from endovascular treatment (EVT) and neurosurgical treatment (NST) of unruptured intracranial aneurysms and risk factors of clinical complications.

Data Sources

We searched PubMed, Excerpta Medica Database, and the Cochrane Database for studies published between January 1, 2011, and January 1, 2017.

Study Selection

Studies reporting on clinical complications, the CFR, and risk factors, including 50 patients or more undergoing EVT or NST for saccular unruptured intracranial aneurysms after January 1, 2000, were eligible.

Data Extraction and Synthesis

Per treatment modality, we analyzed clinical complication risk and the CFR with mixed-effects logistic regression models for dichotomous data. For studies reporting data on complication risk factors, we obtained risk ratios (RRs) or odds ratios (ORs) with 95% CIs and pooled risk estimates with weighted random-effects models.

Main Outcomes and Measures

Clinical complications within 30 days and the CFR.

Results

We included 114 studies (106 433 patients with 108 263 aneurysms). For EVT (74 studies), the pooled clinical complication risk was 4.96% (95% CI, 4.00%-6.12%), and the CFR was 0.30% (95% CI, 0.20%-0.40%). Factors associated with complications from EVT were female sex (pooled OR, 1.06 [95% CI, 1.01-1.11]), diabetes (OR, 1.81 [95% CI, 1.05-3.13]), hyperlipidemia (OR, 1.76 [95% CI, 1.3-2.37]), cardiac comorbidity (OR, 2.27 [95% CI, 1.53-3.37]), wide aneurysm neck (>4 mm or dome-to-neck ratio >1.5; OR, 1.71 [95% CI, 1.38-2.11]), posterior circulation aneurysm (OR, 1.42 [95% CI, 1.15-1.74]), stent-assisted coiling (OR, 1.82 [95% CI, 1.16-2.85]), and stenting (OR, 3.43 [95% CI, 1.45-8.09]). For NST (54 studies), the pooled complication risk was 8.34% (95% CI, 6.25%-11.10%) and the CFR was 0.10% (95% CI, 0.00%-0.20%). Factors associated with complications from NST were age (OR per year increase, 1.02 [95% CI, 1.01-1.02]), female sex (OR, 0.43 [95% CI, 0.32-0.85]), coagulopathy (OR, 2.14 [95% CI, 1.13-4.06]), use of anticoagulation (OR, 6.36 [95% CI, 2.55-15.85]), smoking (OR, 1.95 [95% CI, 1.36-2.79]), hypertension (OR, 1.45 [95% CI, 1.03-2.03]), diabetes (OR, 2.38 [95% CI, 1.54-3.67]), congestive heart failure (OR, 2.71 [95% CI, 1.57-4.69]), posterior aneurysm location (OR, 7.25 [95% CI, 3.70-14.20]), and aneurysm calcification (OR, 2.89 [95% CI, 1.35-6.18]).

Conclusions and Relevance

This study identifies risk factors for procedural complications. Large data sets with individual patient data are needed to develop and validate prediction scores for absolute complication risks and CFRs from EVT and NST modalities.

Functional outcomes and quality of life after microsurgical clipping of unruptured intracranial aneurysms: a prospective cohort study

OBJECTIVE :Few studies have examined patients' ability to drive and quality of life (QOL) after microsurgical repair for unruptured intracranial aneurysms (uIAs). However, without a strong evidentiary basis, jurisdictional road transport authorities have recommended driving restrictions following brain surgery. In the present study, authors examined the outcomes of the microsurgical repair of uIAs by measuring patients' perceived QOL and cognitive abilities related to driving. METHODS: Between January 2011 and January 2016, patients with a new diagnosis of uIA were prospectively enrolled in this study. Assessments were performed at referral, before surgery, and at 6 weeks and 12 months after surgery in those undergoing microsurgical repair and at referral and at 12 months in conservatively managed patients. Assessments included the Physical Component Summary (PCS) and Mental Component Summary (MCS) of the SF-36, the off-road driver-screening instrument DriveSafe (DS), the modified Barthel Index (mBI), and the modified Rankin Scale (mRS). RESULTS: One hundred sixty-nine patients were enrolled in and completed the study, and 112 (66%) of them had microsurgical repair of their aneurysm. In the microsurgical group, there was a trend for improved DS scores: from a mean (± standard deviation) score of 108 ± 10.7 before surgery to 111 ± 9.7 at 6 weeks after surgery to 112 ± 10.2 at 12 months after surgery (p = 0.05). Two percent of the microsurgical repair group and 4% of the conservatively managed group whose initial scores indicated competency to drive according to the DS test subsequently had 12-month scores deemed as not competent to drive; the difference between these 2 groups was not statistically significant (p > 0.99). Factors associated with a decline in the DS score among those who had a license at the time of initial assessment were an increasing age (p < 0.01) and mRS score > 0 at one of the assessments (initial, 6 weeks, or 12 months; p < 0.01). Mean PCS scores in the microsurgical repair group were 52 ± 8.1, 46 ± 6.8, and 52 ± 7.1 at the initial, 6-week, and 12-month assessments, respectively (p < 0.01). These values represented a significant decline in the mean PCS score at 6 weeks that recovered by 12 months (p < 0.01). There were no significant changes in the MCS, mBI, or mRS scores in the surgical group. CONCLUSIONS: Overall, QOL at 12 months for the microsurgical repair group had not decreased and was comparable to that in the conservatively managed group. Furthermore, as assessed by the DS test, the majority of patients were not affected in their ability to drive.

Reporting Interim Results Can Show the Feasibility of Practicing Outcome-Based Neurovascular Care Within Randomized Trials: An Opinion

BACKGROUND

Randomized trials of commonly performed surgical interventions are notoriously difficult to conduct. The trial methodology may nevertheless be the best way to offer outcome-based neurovascular care in the presence of uncertainty. One obstacle to promoting such trials is the conventional prohibition of publication and dissemination of interim results as the trial progresses.

METHODS

We review the scientific and statistical reasons against the publication of interim analyses as well as exceptions that can occur when 1 treatment is unexpectedly shown to be harmful or when the results of other trials have convincingly shown the comparative benefits of a new intervention. We also discuss the promotion of difficult surgical trials.

RESULTS

Reasons to support the conventional ban on publication of interim results include control of statistical errors, prevention of invalid conclusions, and dissemination of false claims of equivalence of rival interventions. In the early phases of a trial, usually 1 treatment cannot be shown superior to the other. We believe, contrary to the received view, that a transparent report of the early progress of certain trials can be justified, even when interim results are inconclusive, to promote the recruitment of participating centers and the practice of a novel way to offer neurovascular care in the presence of uncertainty in the best medical interest of patients.

CONCLUSIONS

In our opinion, the early publication of inconclusive interim results may increase awareness of the feasibility of surgical care trials.

Intracranial Aneurysm: Diagnostic Monitoring, Current Interventional Practices, and Advances

PURPOSE OF REVIEW

Cerebral aneurysms are commonly diagnosed incidentally with non-invasive neuro-imaging modalities (i.e., brain MRA and/or head CTA). The first decision to be made in the management of patients with unruptured cerebral aneurysms is to determine if the aneurysm should undergo treatment as any intervention carries a risk of morbidity and mortality.

RECENT FINDINGS

The multiple risk factors that are associated with increased risk of aneurysm rupture should be evaluated (size, shape, and location of aneurysm; history of hypertension and cigarette smoking and family history of cerebral aneurysms). With the advent and rapid evolution of less traumatic neuro-endovascular surgery techniques in the past two decades, many more patients are undergoing treatment of cerebral aneurysms. The neuro-endovascular surgeon has multiple options for the treatment of aneurysms including coiling, with or without balloon/stent assistance, and flow diversion. A number of intrasaccular devices for the neuro-endovascular treatment of cerebral aneurysms are being evaluated. The percentage of patients with cerebral aneurysms treated with craniotomy and clip ligation is decreasing. This is controversial as it has direct impact in neurosurgical training and the aneurysms that are usually recommended for microsurgical clipping are the ones with challenging anatomy that cannot be treated safely with endovascular approaches. The best outcomes are achieved with management by experienced, high-volume practitioners at specialized cerebrovascular treatment centers that consist of individuals with dedicated training in neuro-endovascular surgery as well as individuals trained in open cerebrovascular neurosurgery.

A randomized pragmatic care trial on endovascular acute stroke interventions (EASI): criticisms, responses, and ethics of integrating research and clinical care

BACKGROUND

The Endovascular Acute Stroke Intervention (EASI) trial was conceived as a pragmatic care trial, designed to integrate trial methods with clinical practice. Reporting the EASI experience was met with objections and criticisms during peer review concerning both scientific and ethical issues. Our goal is to discuss these criticisms in order to promote the pragmatic approach of care trials in outcome-based medical care.

METHODS

The comments and criticisms of 11 reviewers from 5 journals were collected and analyzed. The EASI protocol was also compared to the protocols of seven thrombectomy trials using the pragmatic-explanatory continuum indicator summary (PRECIS).

RESULTS

Main criticisms of EASI concerned selection criteria that were judged to be too vague and too inclusive, brain and vascular imaging methods that were not sufficiently prescribed by protocol, lack of blinding of outcome assessment, and lack of power. EASI was at the pragmatic end of the spectrum of thrombectomy trials.

CONCLUSION

The pragmatic care trial methodology is not currently well-established. More work needs to be done to integrate scientific methods and ethical care in the best medical interest of current patients.

Methods for the evaluation of biomarkers in patients with kidney and liver diseases: multicentre research programme including ELUCIDATE RCT

Background

Protein biomarkers with associations with the activity and outcomes of diseases are being identified by modern proteomic technologies. They may be simple, accessible, cheap and safe tests that can inform diagnosis, prognosis, treatment selection, monitoring of disease activity and therapy and may substitute for complex, invasive and expensive tests. However, their potential is not yet being realised.

Design and methods

The study consisted of three workstreams to create a framework for research: workstream 1, methodology – to define current practice and explore methodology innovations for biomarkers for monitoring disease; workstream 2, clinical translation – to create a framework of research practice, high-quality samples and related clinical data to evaluate the validity and clinical utility of protein biomarkers; and workstream 3, the ELF to Uncover Cirrhosis as an Indication for Diagnosis and Action for Treatable Event (ELUCIDATE) randomised controlled trial (RCT) – an exemplar RCT of an established test, the ADVIA Centaur® Enhanced Liver Fibrosis (ELF) test (Siemens Healthcare Diagnostics Ltd, Camberley, UK) [consisting of a panel of three markers – (1) serum hyaluronic acid, (2) amino-terminal propeptide of type III procollagen and (3) tissue inhibitor of metalloproteinase 1], for liver cirrhosis to determine its impact on diagnostic timing and the management of cirrhosis and the process of care and improving outcomes.

Results

The methodology workstream evaluated the quality of recommendations for using prostate-specific antigen to monitor patients, systematically reviewed RCTs of monitoring strategies and reviewed the monitoring biomarker literature and how monitoring can have an impact on outcomes. Simulation studies were conducted to evaluate monitoring and improve the merits of health care. The monitoring biomarker literature is modest and robust conclusions are infrequent. We recommend improvements in research practice. Patients strongly endorsed the need for robust and conclusive research in this area. The clinical translation workstream focused on analytical and clinical validity. Cohorts were established for renal cell carcinoma (RCC) and renal transplantation (RT), with samples and patient data from multiple centres, as a rapid-access resource to evaluate the validity of biomarkers. Candidate biomarkers for RCC and RT were identified from the literature and their quality was evaluated and selected biomarkers were prioritised. The duration of follow-up was a limitation but biomarkers were identified that may be taken forward for clinical utility. In the third workstream, the ELUCIDATE trial registered 1303 patients and randomised 878 patients out of a target of 1000. The trial started late and recruited slowly initially but ultimately recruited with good statistical power to answer the key questions. ELF monitoring altered the patient process of care and may show benefits from the early introduction of interventions with further follow-up. The ELUCIDATE trial was an ‘exemplar’ trial that has demonstrated the challenges of evaluating biomarker strategies in ‘end-to-end’ RCTs and will inform future study designs.

Conclusions

The limitations in the programme were principally that, during the collection and curation of the cohorts of patients with RCC and RT, the pace of discovery of new biomarkers in commercial and non-commercial research was slower than anticipated and so conclusive evaluations using the cohorts are few; however, access to the cohorts will be sustained for future new biomarkers. The ELUCIDATE trial was slow to start and recruit to, with a late surge of recruitment, and so final conclusions about the impact of the ELF test on long-term outcomes await further follow-up. The findings from the three workstreams were used to synthesise a strategy and framework for future biomarker evaluations incorporating innovations in study design, health economics and health informatics.

Trial registration

Current Controlled Trials ISRCTN74815110, UKCRN ID 9954 and UKCRN ID 11930.

Funding

This project was funded by the NIHR Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 6, No. 3. See the NIHR Journals Library website for further project information.

Indications for the Performance of Intracranial Endovascular Neurointerventional Procedures: A Scientific Statement From the American Heart Association

Intracranial endovascular interventions provide effective and minimally invasive treatment of a broad spectrum of diseases. This area of expertise has continued to gain both wider application and greater depth as new and better techniques are developed and as landmark clinical studies are performed to guide their use. Some of the greatest advances since the last American Heart Association scientific statement on this topic have been made in the treatment of ischemic stroke from large intracranial vessel occlusion, with more effective devices and large randomized clinical trials showing striking therapeutic benefit. The treatment of cerebral aneurysms has also seen substantial evolution, increasing the number of aneurysms that can be treated successfully with minimally invasive therapy. Endovascular therapies for such other diseases as arteriovenous malformations, dural arteriovenous fistulas, idiopathic intracranial hypertension, venous thrombosis, and neoplasms continue to improve. The purpose of the present document is to review current information on the efficacy and safety of procedures used for intracranial endovascular interventional treatment of cerebrovascular diseases and to summarize key aspects of best practice.

Should we still consider clips for basilar apex aneurysms? A critical appraisal of the literature

Background:

Basilar apex aneurysms constitute 5–8% of all intracranial aneurysms, and their treatment remains challenging for both microsurgical and endovascular approaches. The perceived drawback of the microsurgical approach is its invasiveness leading to increased surgical morbidity. However, many high-volume centers have shown excellent clinical results with better occlusion rates compared to endovascular treatment. With endovascular therapy taking a larger role in the management of cerebral aneurysms, the future role of microsurgery for basilar apex aneurysm treatment is unclear.

Methods:

We performed a literature search to review the microsurgical and endovascular outcomes for basilar apex aneurysms.

Results:

Many studies have examined the efficacy of microsurgical and endovascular treatment for intracranial aneurysms, including large randomized trials such as ISAT and BRAT, prospective observational series such as ISUIA, and many single-center retrospective reviews. The recruitment number for posterior circulation aneurysms, specifically for basilar apex aneurysms, was limited in most prospective trials, thus failing to offer clear guidance on basilar apex aneurysm treatment. Recent single-center series report good clinical outcomes between 57–92% for surgical series and 73–96% in endovascular series. The durability of aneurysm occlusion remains superior in surgical cases. The techniques and devices in endovascular treatment have improved treatment aneurysm occlusion rates but more follow-up is needed to confirm long-term durability.

Conclusions:

Both microsurgical and endovascular approaches should be complementing each other to treat basilar apex aneurysms. Although endovascular therapy has taken a larger role in the treatment of basilar apex aneurysms, many indications still exist for the use of microsurgery. Advancements in microsurgical techniques and good case selection will allow for acceptably low morbidity after surgical treatment while maintaining its superior durability.

The Treatment of Brain AVMs Study (TOBAS): an all-inclusive framework to integrate clinical care and research

OBJECTIVE The management of brain arteriovenous malformations (bAVMs) remains controversial. The Treatment of Brain AVMs Study (TOBAS) was designed to manage patients with bAVMs within a clinical research framework. The objective of this study was to study trial feasibility, recruitment rates, patient allocation to the various management groups, and compliance with treatment allocation. METHODS TOBAS combines two randomized care trials (RCTs) and a registry. Designed to be all-inclusive, the study offers randomized allocation of interventional versus conservative management to patients eligible for both options (first RCT), a second RCT testing the role of preembolization as an adjunct to surgery or radiotherapy, and a registry of patients managed using clinical judgment alone. The primary outcome of the first RCT is death from any cause or disabling stroke (modified Rankin Scale score > 2) at 10 years. A pilot phase was initiated at one center to test study feasibility, record the number and characteristics of patients enrolled in the RCTs, and estimate the frequency of crossovers. RESULTS All patients discussed at the multidisciplinary bAVM committee between June 2014 and June 2016 (n = 107) were recruited into the study; 46 in the randomized trials (23 in the first RCT with 21 unruptured bAVMs, 40 in the second RCT with 17 unruptured bAVMs, and 17 in both RCTs), and 61 patients in the registry. Three patients crossed over from surgery to observation (first RCT). CONCLUSIONS Clinical research was successfully integrated with normal practice using TOBAS. Recruitment rates in a single center are encouraging. Whether the trial will provide meaningful results depends on the recruitment of a sufficient number of participating centers. Clinical trial registration no.: NCT02098252 (clinicaltrials.gov).

Surgical clipping or endovascular coiling for unruptured intracranial aneurysms: a pragmatic randomised trial

BACKGROUND

Unruptured intracranial aneurysms (UIAs) are increasingly diagnosed and are commonly treated using endovascular treatment or microsurgical clipping. The safety and efficacy of treatments have not been compared in a randomised trial. How to treat patients with UIAs suitable for both options remains unknown.

METHODS

We randomly allocated clipping or coiling to patients with one or more 3-25 mm UIAs judged treatable both ways. The primary outcome was treatment failure, defined as: initial failure of aneurysm treatment, intracranial haemorrhage or residual aneurysm on 1-year imaging. Secondary outcomes included neurological deficits following treatment, hospitalisation >5 days, overall morbidity and mortality and angiographic results at 1 year.

RESULTS

The trial was designed to include 260 patients. An analysis was performed for slow accrual: 136 patients were enrolled from 2010 through 2016 and 134 patients were treated. The 1-year primary outcome, available for 104 patients, was reached in 5/48 (10.4% (4.5%-22.2%)) patients allocated surgical clipping, and 10/56 (17.9% (10.0%-29.8%)) patients allocated endovascular coiling (OR: 0.54 (0.13-1.90), p=0.40). Morbidity and mortality (modified Rankin Scale>2) at 1 year occurred in 2/48 (4.2% (1.2%-14.0%)) and 2/56 (3.6% (1.0%-12.1%)) patients allocated clipping and coiling, respectively. New neurological deficits (15/65 vs 6/69; OR: 3.12 (1.05-10.57), p=0.031), and hospitalisations beyond 5 days (30/65 vs 6/69; OR: 8.85 (3.22-28.59), p=0.0001) were more frequent after clipping.

CONCLUSION

Surgical clipping or endovascular coiling of UIAs did not show differences in morbidity at 1 year. Trial continuation and additional randomised evidence will be necessary to establish the supposed superior efficacy of clipping.

PHASES Score for the Management of Intracranial Aneurysm: A Cross-Sectional Population-Based Retrospective Study

BACKGROUND AND PURPOSE

The aim of this study is to assess whether the PHASES score allows to (1) match decisions taken by multidisciplinary team whether to observe or intervene, (2) classify patients being diagnosed with a ruptured versus unruptured intracranial aneurysm (UIA), and (3) discriminate patients at low risk of rupture from the population of patients diagnosed with intracranial aneurysm.

METHODS

Population-based prospective and consecutive data were collected between 2006 and 2014. Patients (n=841) were stratified into 4 groups: stable UIA; growing observed UIA; immediately treated UIA; and aneurysmal subarachnoid hemorrhage (aSAH). All patients initially observed were pooled in a follow-up UIA group; patients from growing observed UIA, immediately treated UIA, and aSAH were pooled in a high risk of rupture group. Results are expressed as median [quartile 1, quartile 3].

RESULTS

PHASES scores of immediately treated UIA patients were significantly higher than follow-up UIA group (5 [3, 7] versus 2 [1, 4]). Patients diagnosed with UIA and PHASES score of >3 were more likely to be treated, and the score ≤3 was predictive for observation (areas under these curves=0.74). Odds of being diagnosed with an aSAH were associated with PHASES score of >3 (UIA, 4 [2, 6]; aSAH, 5 [4, 8]; areas under these curves=0.66). Scores of stable UIA patients were significantly lower than high risk of rupture group (2 [1, 4] versus 5 [4, 7]; stable UIA outcome prediction by PHASES score of ≤3: areas under these curves=0.76).

CONCLUSIONS

There is a progression of PHASES score between stable UIA, growing observed UIA, immediately treated UIA, and aSAH groups. PHASES score of ≤3 is associated with a low but not negligible likelihood of aneurysm rupture, and specificity of the classifier is low.

Embolization with larger-caliber coils can increase packing density: Evidence from the pilot phase of a randomized trial

Background and purpose Endovascular coil embolization of cerebral aneurysms is associated with suboptimal angiographic results in up to 20-30% of patients. Coil packing density has been used as an index of the success of the initial procedure. The trial sought to study the effects of using 15-caliber coils, as compared with 10-caliber coils, on packing density. Methods Does Embolization with Larger coils lead to better Treatment of Aneurysms (DELTA) is an investigator-initiated multicenter prospective, randomized, controlled clinical trial. Patients are randomized 1:1 to embolization with either 10-caliber coils exclusively (control group) or the highest safely achievable proportion of 15-caliber coils and 10-caliber coils if necessary (intervention group) in 4-12-mm aneurysms. The endpoint of the pilot phase of the trial was the capacity to increase packing density of the initial procedure, calculated using a mathematical transformation of the dimensions entered into the case report forms. Secondary outcomes included the total number of coils used per aneurysm, total fluoroscopy time, initial angiographic outcomes and any adverse or undesirable event. Results Seventy patients were recruited between June 2014 and November 2015. Compared with 10-caliber coils, the 15-caliber coil group had a higher median packing density (44% vs 24%, p = 0.017). Results of other outcome measures were similar for the two groups. Conclusion Coiling of small and medium aneurysms randomized to 15-caliber coils achieved higher packing densities compared with coiling using 10-caliber coils.

Factors influencing management of unruptured intracranial aneurysms: an analysis of 424 consecutive patients

OBJECTIVE The choice between treating and observing unruptured intracranial aneurysms is often difficult, with little guidance on which variables should influence decision making on a patient-by-patient basis. Here, the authors compared demographic variables, aneurysm-related variables, and comorbidities in patients who received microsurgical or endovascular treatment and those who were conservatively managed to determine which factors push the surgeon toward recommending treatment. METHODS A retrospective chart review was conducted of all patients diagnosed with an unruptured intracranial aneurysm at their institution between January 1, 2013, and January 1, 2016. These patients were dichotomized based on whether their aneurysm was treated. Demographic, geographic, socioeconomic, comorbidity, and aneurysm-related information was analyzed to assess which factors were associated with the decision to treat. RESULTS A total of 424 patients were identified, 163 who were treated surgically or endovascularly and 261 who were managed conservatively. In a multivariable model, an age < 65 years (OR 2.913, 95% CI 1.298-6.541, p = 0.010), a lower Charlson Comorbidity Index (OR 1.536, 95% CI 1.274-1.855, p < 0.001), a larger aneurysm size (OR 1.176, 95% CI 1.100-1.257, p < 0.001), multiple aneurysms (OR 2.093, 95% CI 1.121-3.907, p = 0.020), a white race (OR 2.288, 95% CI 1.245-4.204, p = 0.008), and living further from the medical center (OR 2.125, 95% CI 1.281-3.522, p = 0.003) were all associated with the decision to treat rather than observe. CONCLUSIONS Whereas several factors were expected to be considered in the decision to treat unruptured intracranial aneurysms, including age, Charlson Comorbidity Index, aneurysm size, and multiple aneurysms, other factors such as race and proximity to the medical center were unanticipated. Further studies are needed to identify such biases in patient treatment and improve treatment delineation based on patient-specific aneurysm rupture risk.