Objectives: To describe surgical experience in the repair of anterior skull base defects, we studied patients with congenital or acquired defects. According to a multidisciplinary evaluation, all subjects underwent surgery performed by an ENT surgeon in order to avoid craniotomy.
Design: Retrospective study of patients who were treated for an anterior skull base defect between 2000 and 2005 at a tertiary referral centre.
Materials and methods: Twelve patients had surgery to correct anterior skull base defects. Four patients had spontaneous anterior basal defect and eight had a post-traumatic cerebrospinal fluid (CSF) leakage. The diagnosis was made with imaging studies: Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans, possibly supplemented by a cisternography. The defects were repaired using the endoscopic endonasal approach excepted in frontal sinus location.
Results: CT and MRI scans demonstrated the defect in all but two cases. In one of them, MR cisternography showed the intranasal sac and in the other CT cisternography demonstrated a CSF fistula without any bone defect at the ethmoid roof. After surgery, the follow-up period was at least 16 months (mean 26 months). Success rate at first attempt was 83%. Two adults needed a second surgical repair with successful outcome in one, increasing the success rate to 92% after the second attempt. One female patient, obese with a body mass index > 30 and hydrocephaly, had a recurrence of CSF leakage despite surgical revision. Postoperative imaging studies, CT scan or MRI, showed that the defect had successfully been repaired in 11 patients.
Conclusion: High-resolution CT scan, MRI with or without cisternography, should investigate osteo-meningeal defect. Our report confirms that endonasal surgical techniques are useful for treating meningoceles and meningo-encephaloceles. The external route is to be preferred when the lesion is located in the apex of the frontal sinus.