A Morphometric Analysis of the Foramen Ovale and the Zygomatic Points Determined by a Computed Tomography in Patients with Idiopathic Trigeminal Neuralgia

ABSTRACT

OBJECTIVE: The purpose of this study is to measure the dimensions of foramen ovale and to localize the zygomatic point using computed tomography(CT) in Korean adults with idiopathic trigeminal neuralgia. METHODS: Facial axial CT scans using the orbitomeatal plane were performed in 67patients (39males and 28females; mean age 58.8years) with idiopathic classic trigeminal neuralgia. We measured the size of the foramen ovale and localized the zygomatic point which was a skin marker over the ipsilateral zygoma that approximates the lateral projection of a straight line joining the centers of the two foramen ovale. RESULTS: The axial dimensions of the foramen ovale on the orbitomeatal plane were of average length 8.18+/-0.82mm (range 6.9~11.5mm), width 4.06+/-0.86mm (2.5~5.7mm). The average distance between the external acoustic meatus and the zygomatic point was 21.64+/-1.99mm (16.3~25.0mm) and the average distance of anterior margin of condylar process of mandible to zygomatic point was 4.29+/-1.19mm (1.0~7.0mm). CONCLUSION: The anatomical understandings including the size of the foramen ovale and localization of the zygomatic point could be helpful in determining a plan of percutaneous approaches to foramen ovale.