EXPERIENCES IN DIAGNOSIS OF OCCULT TRAUMA TIC DURAL LESIONS OF THE FRONTAL SKULL BASE

Background: Meningitis or cerebrospinal fluid rhinorrhea can occur yea rs or even decades after trauma and can be the first indication of a p reviously unidentified dural lesion. In spite of being difficult, prec ise localization of an occult traumatic dural lesion is a necessary pr erequisite for duraplasty. Patients and methods: In a retrospective st udy covering a period of 17 years, we identified 27 patients with occu lt traumatic dural lesions. The dural lesions were localized by high-r esolution CT, MRI, fluorescein nasal endoscopy, and CT cisternography. In all cases the expected dural lesion was demonstrated and treated s urgically. Results: In 23 out of 27 patients (85%), the rhinobasal fis tula was detected as a bony defect by CT. Furthermore MRI examination in 100% (51 5), a preoperative fluorescein nasal endoscopy in 50% (10/ 20) and CT cisternography in 56% (5/9) were able to localize the dural lesion. Conclusion: We recommend high-resolution CT and MRI as diagno stic tools of choice in searching for occult dural lesions. Fluorescei n nasal endoscopy and CT cisternography are justified as invasive tech niques if CT and MRI are inconclusive but clinically CSF leakage is st ill suggested, The patient will remain at risk of potentially fatal me ningitis until the lesion is appropriately repaired by duraplasty. The refore modern clinical and radiological diagnostic methods should be u sed to search for an unknown dural lesion.