Table 3

Periprocedural events, with or without clinical consequences and adjudication of causality by the clinical event adjudicator (CEA)

Periprocedural eventsNumber of events, %Clinical consequencesRelated to WEBRelated to WEB and/or procedureRelated to procedure and/or disease
Thromboembolic event10 (16.7%)
 Thromboembolic event: no perfusion deficit*5032
 Thromboembolic event: perfusion deficit†3121
 Stroke‡111
 Thrombosis: parent or branch artery§101
Perioperative rupture2 (3.3%)02
Vasospasm4 (6.7%)
 Vasospasm depicted on angiogram303
 Vasospasm clinical111
Hydrocephalus1 (1.7%)01
Headache1 (1.7%)01
Other, non-neurological5 (8.5%)0
  • *Thromboembolic event: no perfusion deficit, defined as thrombus observed in distal vasculature but not affecting flow to that region.

  • †Thromboembolic event: perfusion deficit observed, defined as thrombus observed in distal vasculature and perfusion deficit observed in that region.

  • ‡Stroke, defined as new neurologic deficit of presumed vascular origin, persisting for more than 24 hours in the absence of a neuroimaging study clearly indicating a different etiology. This definition includes a vasospasm-induced ischemic event associated with the index procedure.

  • §Thrombosis: parent or branch artery, defined as thrombus observed at the WEB - parent vessel interface or in a branch vessel (eg, temporary posterior cerebral artery (PCA) occlusions with WEB (size too big), which resulted in thrombus in the PCA and had to be treated either with stent or with drug; or also one thrombus observed on the WEB and treated with drug).