Lower cranial nerves function after surgical treatment of Fisch Class C and D tympanojugular paragangliomas

Abstract

The aim of this study was to report the postoperative lower cranial nerves (LCNs) function in patients undergoing surgery for tympanojugular paraganglioma (TJP) and to evaluate risk factors for postoperative LCN dysfunction. A retrospective case review of 122 patients having Fisch class C or D TJP, surgically treated from 1988 to 2012, was performed. The follow-up of the series ranged from 12 to 156 months (mean, 39.4 ± 32.6 months). The infratemporal type A approach was the most common surgical procedure. Gross total tumor removal was achieved in 86% of cases. Seventy-two percent of the 54 patients with preoperative LCN deficit had intracranial tumor extension. Intraoperatively, LCNs had to be sacrificed in 63 cases (51.6%) due to tumor infiltration. Sixty-six patients (54.09%) developed a new deficit of one or more of the LCNs. Of those patients who developed new LCN deficits, 23 of them had intradural extension. Postoperative follow-up of at least 1 year showed that the LCN most commonly affected was the CN IX (50%). Logistic regression analysis showed that intracranial transdural tumor extension was correlated with the higher risk of LCN sacrifice (p < 0.05). Despite the advances in skull base surgery, new postoperative LCN deficits still represent a challenge. The morbidity associated with resection of the LCNs is dependent on the tumor's size and intradural tumor extension. Though no recovery of LCN deficits may be expected, on long-term follow-up, patients usually compensate well for their LCNs loss.