Fig. 2

A-H Characteristics of population with large (≥ 5% point) benefit from neurosurgical clip-reconstruction

Abbreviations: ACA = anterior circulation artery, ACOM = anterior communicating artery, CT = computed tomography, ICA = internal carotid artery, MCA = middle cerebral artery, PCOM = posterior communicating artery, Post = aneurysms of the posterior circulation, WFNS = World Federation of Neurological Surgeons. Locations of aneurysms of the posterior circulation include: basilar artery, vertebral artery, superior cerebellar artery, anterior inferior cerebellar artery, posterior inferior cerebellar artery, and internal auditory artery. Each dot corresponds to a patient in the International Subarachnoid Aneurysm Trial. The dashed lines indicate a ≥ 5% point difference in predicted probability of favorable functional (modified Rankin Scale 0–2) at 2 months or the difference in predicted probability of no rebleed or retreatment within a 10-year follow-up. Because no interactions were included in the models, every patient in the ISAT cohort had benefit of endovascular coiling in terms of functional outcome and benefit of clip-reconstruction in terms of durability of treatment. The values on the axis are calculated by subtracting the predicted probabilities of outcome. X-axis: P(mRS < 3) with endovascular coiling – P(mRS < 3) with neurosurgical clip-reconstruction, and on the y-axis P(No event within 10 years) with neurosurgical clip-reconstruction – P(No event within 10 years) with endovascular coiling. This creates four quadrants: Upper left quadrant: Population which should be considered for neurosurgical clip-reconstruction instead of endovascular coiling because of negligible benefit in functional outcome and ≥ 5% point difference in durability of treatment favoring neurosurgical clip-reconstruction. Lower left quadrant: Treat according to current guideline recommendations. No ≥ 5% point difference in treatment benefit with both outcomes. Upper right quadrant: Treat according to current guideline recommendations. A ≥ 5% point difference in treatment benefit for both outcomes. Lower right quadrant: Treat according to current guideline recommendations. Only ≥ 5% point difference in treatment benefit from endovascular coiling in terms of functional outcome