Citations

Objective: We previously derived the Unruptured Intracranial Aneurysm Treatment Score (UIATS), designed using a multidisciplinary consensus approach among neurovascular specialists from diverse geographic and practice backgrounds. Here, we report on the development and validation of the final version of UIATS. Method: An international, multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 (39 panel members and 30 blinded external reviewers) specialists in the research and treatment of UIAs was convened. A web survey-based Delphi consensus process consisting of 7 rounds was utilized to rate numerous features of potential relevance in the assessment and treatment of UIAs and to develop the UIATS. Mean ratings were repeatedly used to determine statistical weight for each factor and then transformed into corresponding scores for every item to create the UIATS. For internal and blinded external validation, 30 representative cases of patients with UIAs were used to test the level of agreement (5 point Likert Scale) with treatment recommendations based on the UIATS. Results: The final UIATS system was designed in three domains (patient-, aneurysm - and treatment-related), comprising 13 different categories and 29 different features (Figure 1). Mean agreement based on Likert scores (5 indicating strong agreement and 1 indicating strong disagreement) was 4·2 for both reviewer cohorts, whereas mean agreement per case was 4·2 (panel members) and 4·5 (external reviewers) (p=0·017, Mann-Whitney-U Test). Conclusion: The final version of UIATS system was internally and externally validated by a large multidisciplinary group of neurovascular specialists, which suggests that the UIATS reflects contemporary decision-making regarding management of a patient with an UIA. The UIATS may aid clinicians in deciding on the appropriate management for an UIA.

OBJECTIVE Indication for surgery in brainstem cavernous malformations (BSCMs) is based on many case series, few comparative studies, and no randomized controlled trials. The objective of this study was to seek consensus about surgical management aspects of BSCM. METHODS A total of 29 experts were invited to participate in a multistep Delphi consensus process on the surgical treatment of BSCM. RESULTS Twenty-two (76%) of 29 experts participated in the consensus. Qualitative analysis (content analysis) of an initial open-ended question survey resulted in 99 statements regarding surgical treatment of BSCM. By using a multistep survey with 100% participation in each round, consensus was reached on 52 (53%) of 99 statements. These were grouped into 4 categories: 1) definitions and reporting standards (7/14, 50%); 2) general and patient-related aspects (11/16, 69%); 3) anatomical-, timing of surgery–, and BSCM-related aspects (22/37, 59%); and 4) clinical situation–based decision-making (12/32, 38%). Among other things, a consensus was reached for surgical timing, handling of associated developmental venous anomalies, handling of postoperative BSCM remnants, assessment of specific anatomical BSCM localizations, and treatment decisions in typical clinical BSCM scenarios. CONCLUSIONS A summary of typical clinical scenarios and a catalog of various BSCM- and patient-related aspects that influence the surgical treatment decision have been defined, rated, and interpreted.

Background and Purpose— The chronological development and natural history of cerebral aneurysms (CAs) remain incompletely understood. We used 14 C birth dating of a main constituent of CAs, that is, collagen type I, as an indicator for biosynthesis and turnover of collagen in CAs in relation to human cerebral arteries to investigate this further. Methods— Forty-six ruptured and unruptured CA samples from 43 patients and 10 cadaveric human cerebral arteries were obtained. The age of collagen, extracted and purified from excised CAs, was estimated using 14 C birth dating and correlated with CA and patient characteristics, including the history of risk factors associated with atherosclerosis and potentially aneurysm growth and rupture. Results— Nearly all CA samples contained collagen type I, which was <5 years old, irrespective of patient age, aneurysm size, morphology, or rupture status. However, CAs from patients with a history of risk factors (smoking or hypertension) contained significantly younger collagen than CAs from patients with no risk factors (mean, 1.6±1.2 versus 3.9±3.3 years, respectively; P =0.012). CAs and cerebral arteries did not share a dominant structural protein, such as collagen type I, which would allow comparison of their collagen turnover. Conclusions— The abundant amount of relatively young collagen type I in CAs suggests that there is an ongoing collagen remodeling in aneurysms, which is significantly more rapid in patients with risk factors. These findings challenge the concept that CAs are present for decades and that they undergo only sporadic episodes of structural change.

Background and Purpose— To address the increasing need to counsel patients about treatment indications for unruptured intracranial aneurysms (UIA), we endeavored to develop a consensus on assessment of UIAs among a group of specialists from diverse fields involved in research and treatment of UIAs. Methods— After composition of the research group, a Delphi consensus was initiated to identify and rate all features, which may be relevant to assess UIAs and their treatment by using ranking scales and analysis of inter-rater agreement (IRA) for each factor. IRA was categorized as very high, high, moderate, or low. Results— Ultimately, 39 specialists from 4 specialties agreed (high or very high IRAs) on the following key factors for or against UIA treatment decisions: (1) patient age, life expectancy, and comorbid diseases; (2) previous subarachnoid hemorrhage from a different aneurysm, family history for UIA or subarachnoid hemorrhage, nicotine use; (3) UIA size, location, and lobulation; (4) UIA growth or de novo formation on serial imaging; (5) clinical symptoms (cranial nerve deficit, mass effect, and thromboembolic events from UIAs); and (6) risk factors for UIA treatment (patient age and life expectancy, UIA size, and estimated risk of treatment). However, IRAs for features rated with low relevance were also generally low, which underlined the existing controversy about the natural history of UIAs. Conclusions— Our results highlight that neurovascular specialists currently consider many features as important when evaluating UIAs but also highlight that the appreciation of natural history of UIAs remains uncertain, even within a group of highly informed individuals.

Background and Purpose— In clinical trials and observational studies there is considerable inconsistency in the use of definitions to describe delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage. A major cause for this inconsistency is the combining of radiographic evidence of vasospasm with clinical features of cerebral ischemia, although multiple factors may contribute to DCI. The second issue is the variability and overlap of terms used to describe each phenomenon. This makes comparisons among studies difficult. Methods— An international ad hoc panel of experts involved in subarachnoid hemorrhage research developed and proposed a definition of DCI to be used as an outcome measure in clinical trials and observational studies. We used a consensus-building approach. Results— It is proposed that in observational studies and clinical trials aiming to investigate strategies to prevent DCI, the 2 main outcome measures should be: (1) cerebral infarction identified on CT or MRI or proven at autopsy, after exclusion of procedure-related infarctions; and (2) functional outcome. Secondary outcome measure should be clinical deterioration caused by DCI, after exclusion of other potential causes of clinical deterioration. Vasospasm on angiography or transcranial Doppler can also be used as an outcome measure to investigate proof of concept but should be interpreted in conjunction with DCI or functional outcome. Conclusion— The proposed measures reflect the most relevant morphological and clinical features of DCI without regard to pathogenesis to be used as an outcome measure in clinical trials and observational studies.