Recovery of third nerve palsy after endovascular treatment of posterior communicating artery aneurysms

Abstract 

Background

High recovery rates after endovascular treatment of TNP-inducing PcomA aneurysms have been reported. However, only few and often small series were reported. The results of the 2 available comparative studies are controversial. Choosing clipping or coiling as treatment modality nowadays is still a matter of debate. We report the ophthalmologic outcome of 20 consecutive patients treated by coiling of TNP-inducing PcomA aneurysms.

Methods

The third nerve function before and after endovascular treatment was assessed and studied retrospectively. Predictive recovery factors known from literature including treatment timing, the degree of preoperative nerve deficit, the association with SAH, coil type, cardiovascular risk factors, and age were analyzed. A review of the literature was performed.

Results

Eight patients presented initially with complete nerve palsy (40%) and 12 with partial palsy (60%). Eleven patients had SAH. The mean aneurysm size was 7.14 mm; there were no partially thrombosed aneurysms. Of the 20 patients, 19 (95%) recovered. Recovery was complete in 7 patients (35%), partial in 12 patients (60%), and 1 patient remained unchanged (5%). The mean duration of follow-up was 24.7 months. One patient with complete TNP recovered completely after 5 months of coiling. One case of late complete nerve recovery was observed at 20 months. No cases of reoccurrences or worsening of the partial TNP were observed, including patients who developed recanalization of the aneurysmal sac.

Clinical presentation with SAH and early management were statistically significant factors that positively influenced nerve recovery (P = .006549 and P = .015718, respectively). Initial partial TNP seems to influence recovery but did not reach significance (P = .079899).

Conclusion

Coiling of PcomA aneurysms is associated with high rates of third nerve function recovery. Complete recovery can be expected even after long periods and in cases of initial complete nerve palsy. The early treatment and the association with SAH seem to promote the nerve recovery.

Abbreviations: CT, computed tomography, DSA, digital subtraction angiography, GCS, Glasgow Coma Scale, MCA, middle cerebral artery, MRI, magnetic resonance imaging, MRA, magnetic resonance angiography, PcomA, posterior communicating artery, SAH, subarachnoid hemorrhage, TNP, third nerve palsy, WFNS, World Federation of Neurosurgical Societies

Keywords: Third nerve palsy, Posterior communicating artery aneurysm, Endovascular treatment