Validity of the Meyer scale for assessment of coiled aneurysms and aneurysm recurrence

BACKGROUND AND PURPOSE: Both the Meyer and Raymond scales are commonly used to report angiographic outcomes following coil embolization of intracranial aneurysms. The objectives of this study were the following: 1) to assess the interobserver agreement of the Meyer and Raymond scales, and 2) to evaluate and compare their performance in predicting major recurrence at follow-up. MATERIALS AND METHODS: A retrospective series of 120 coiled aneurysms was included. Four investigators independently graded DSA images immediately posttreatment and at follow-up according to the Meyer and Raymond scales. On follow-up DSA, readers also evaluated recurrence outcome. Interobserver agreement was assessed via the intraclass correlation coefficient. The ability of posttreatment Meyer and Raymond scales to predict major recurrence was modeled by using logistic regression and assessed by using receiver operating characteristic analysis. RESULTS: For the Meyer scale, interobserver intraclass correlation coefficients were 0.58 (95% CI, 0.46- 0.68) on posttreatment and 0.78 (95% CI, 0.72-0.83) on follow-up evaluations. For the Raymond scale, interobserver intraclass correlation coefficients were 0.50 (95% CI, 0.39- 0.61) and 0.69 (95% CI, 0.62- 0.76), respectively, for posttreatment and follow-up. The areas under the curve for the receiver operating characteristic analyses regarding the performance to predict major recurrence at follow-up were 0.69 (95% CI, 0.60-0.79) for the Meyer and 0.70 (95% CI, 0.61-0.78) for the Raymond scale. CONCLUSIONS: The Meyer scale appears consistent and reliable with observer agreement as high or higher than that of the Raymond scale. Performance of both scales in predicting the risk of major recurrence at follow-up is adequate, with no statistical difference between the scales.