Vertebral artery-posteroinferior cerebellar artery aneurysms: Clinical and lower cranial nerve outcomes in 52 patients

OBJECTIVE: To identify factors predictive of postoperative lower cranial nerve palsy (LCNP) among patients undergoing surgery for vertebral artery (VA)- posteroinferior cerebellar artery (PICA) aneurysms. The natural history of this LCNP is defined, and its effect on postoperative patient course is analyzed. No similar study has been described in the literature. METHODS: Fifty-two patients with VA-PICA aneurysms, who were treated surgically between 1996 and 2002, were retrospectively studied to identify factors contributing to postoperative LCNP. The effect of LCNP on intensive care unit stay and development of nosocomial pneumonia also was analyzed. All analyses were performed with Fisher's exact test. RESULTS: Postoperative LCNP occurred in 25 patients (48.1%) with VA-PICA aneurysms. Of the factors investigated, the use of temporary or total occlusion was associated with increased incidence of postoperative LCNP (P < 0.001). The average length of stay in the intensive care unit was 13.8 days for patients with LCNP defined as moderate to severe, compared with 7.92 days for patients with LCNP defined as none or mild (P = 0.0014). Nosocomial pneumonia occurred only in patients with moderate to severe LCNP (P = 0.022). Postoperative LCNP resolved completely within 3 months in 12 patients (48%) and within 6 months in 19 patients (76%). CONCLUSION: The results of this study can help to identify the effect and natural history of LCNP after surgical clipping of VA-PICA aneurysms. This information may assist neurosurgeons in expediting treatment, decrease the cost and length of hospital stays, and result in improved outcomes.