Outcomes of Microsurgical Clipping of Recurrent Aneurysms After Endovascular Coiling

Background The outcomes of microsurgery of previously coiled aneurysms have been poorly described, and little is known about the factors predictive of poor outcome. Here we aimed to identify predictors of poor outcome following microsurgery for previously coiled recurrent aneurysms. Methods In this retrospective cohort study of a prospectively maintained vascular database, we reviewed presentations, recurrent aneurysm measurements, surgery, and outcomes of microsurgical clipping of recurrent previously coiled intracranial aneurysms. Results Our series comprised 39 patients (mean age, 49 years; range, 22–70 years) who underwent microsurgical clipping of 40 previously coiled intracranial aneurysms. One patient suffered seizures, 1 patient experienced transient neurologic worsening, and 1 patient developed hyponatraemia, none of whom had long-term sequelae. Two patients sustained postoperative infarcts, for an overall incidence of permanent morbidity of 5.1%. There were no deaths or rebleeds on follow-up. In 3 patients, including the 2 patients with infarct and 1 patient with a transient deficit, an attempt was made to remove the coil ball. These patients had larger aneurysms (1106 mm 3 vs. 135 mm 3 ; P  = 0.005), with larger coil balls (257 mm 3 vs. 52 mm 3 ; P  = 0.01) and wider necks (7.09 mm vs. 2.69 mm; P  = 0.02) but smaller remnant heights (1.59 mm vs. 1.99 mm; P  = 0.04). They were also more likely to have prolapsing coil loops (3/3 vs. 3/27; P  = 0.016). Conclusions Our study demonstrates good clinical outcomes from microsurgical clipping of recurrent aneurysms. In the vast majority of cases, clips can be applied primarily. Coil ball removal is associated with increased morbidity, and thus should be considered only as a second-line option, with the likely need identified before the initiation of surgery.