Objective: To compare multidisciplinary team (MDT) decision making at our centre with the suggested management from the recently published Unruptured Intracranial Aneurysm Treatment Score (UIATS), with particular focus on disagreements between the two bodies of expert opinion.
Design: A retrospective audit of local practice.
Subjects: Adult patients with incidental cerebral saccular aneurysms referred to The National Hospital for Neurology and Neurosurgery Neurovascular MDT.
Methods: Review of MDT records from 2010-2015 and collection of UIATS criteria. MDT decisions for each aneurysm were designated as conservative or treatment group, then assessed for correlation with the UIATS.
Results: Data was collected on 398 aneurysms from 296 patients. 57% of aneurysms were managed conservatively and 43% were treated with endovascular or open repair. Total follow up was 8409 aneurysm months (mean: 21 months per aneurysm). The overall proportion of agreement (p0) was 66.6% (95% CI: 61.9-71.2). Cohen's Kappa (k) was 0.325 suggesting only a "fair" level of agreement between the two raters. Absolute agreement rates increased from 60% in 2010 to 74% in 2015. Aneurysm size was an important factor for disagreement, 77% of aneurysms treated following MDT, but not in agreement with the UIATS, were >7 mm, compared with only 70.5% in those treated following MDT and in agreement with UIATS.
Conclusion: There was disagreement between the two expert opinions analysed in this study. A key factor was aneurysm size, with decision making at our centre seemingly more guided by older landmark papers such as work by the International Study of Unruptured Intracranial Aneurysms (ISUIA) group. However, agreement was at its highest at the end of the study period, suggesting increasing convergence between the two bodies of expert opinion. The reasons for disagreement and particularly clinicians' reliance on aneurysm size in decision making is something that needs consideration when planning and auditing aneurysm services.
Keywords: Aneurysm; haemorrhage; incidental; subarachnoid; unruptured.